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Cursitor Doom

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Nov 10, 2019, 8:37:37 AM11/10/19
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So I've had this HP RF VNA in mothballs for the last 10 years (and I
*know* it's exactly 10 years) which I decided to fire-up. Being as it's
been a while, I took it up very slowly with a variac, beginning Friday
evening (I checked the service manual first and it's got a linear PSU)
and by the time I got to late morning on Sunday I had it up to 230V
(which is only 10 less than the local supply) and all seemed well. It had
been fine on this for a good hour when out of nowhere there was a
**bang** and a funny smell. I was in the shower 30 feet away when it
happened but could still hear it from there so it was pretty loud.

[short time later...]

I whipped off the case and made my way to a row of large electrolytics
(the usual suspects). These are the big, blue Sprague 'Powerlytics' (TM)
That HP were very fond of using back in the day (c.1980) but they have
all tested fine for capacity and ESR. That's my prime theory out the
window, then. No visible signs inside what could have catastrophically
failed, just the unmistakable smell that *something* has. The device
still powers up fine and the screen traces are normal, so wtf else goes
*bang* and smells toxic?



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Michael Terrell

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Nov 10, 2019, 8:59:42 AM11/10/19
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On Sunday, November 10, 2019 at 8:37:37 AM UTC-5, Cursitor Doom wrote:
> So I've had this HP RF VNA in mothballs for the last 10 years (and I
> *know* it's exactly 10 years) which I decided to fire-up. Being as it's
> been a while, I took it up very slowly with a variac, beginning Friday
> evening (I checked the service manual first and it's got a linear PSU)
> and by the time I got to late morning on Sunday I had it up to 230V
> (which is only 10 less than the local supply) and all seemed well. It had
> been fine on this for a good hour when out of nowhere there was a
> **bang** and a funny smell. I was in the shower 30 feet away when it
> happened but could still hear it from there so it was pretty loud.
>
> [short time later...]
>
> I whipped off the case and made my way to a row of large electrolytics
> (the usual suspects). These are the big, blue Sprague 'Powerlytics' (TM)
> That HP were very fond of using back in the day (c.1980) but they have
> all tested fine for capacity and ESR. That's my prime theory out the
> window, then. No visible signs inside what could have catastrophically
> failed, just the unmistakable smell that *something* has. The device
> still powers up fine and the screen traces are normal, so wtf else goes
> *bang* and smells toxic?

The capacitors on the AC line input crack and adsorb moisture, Then the explode, along with the smell of burning plastic. They are a common failure in older HP test equipment. Once the short clears, the equipment will operate, but not in a safe manor. Most people replace the entire filter, rather than the capacitors. The ones that fail are mostly the same brand. There are a lot of comments about these on https://groups.io/g/HP-Agilent-Keysight-equipment replacement user group for the old Yahoo groups.

Fox's Mercantile

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Nov 10, 2019, 9:37:30 AM11/10/19
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On 11/10/19 7:59 AM, Michael Terrell wrote:
> The capacitors on the AC line input crack and adsorb moisture,
> Then the explode, along with the smell of burning plastic.
> They are a common failure in older HP test equipment.

I used to repair test equipment at Hughes Aircraft.
I was surprised to find that HP used Sprague Black Beauty
capacitors in their older equipment.
Regardless of the reason it was on the bench, standard procedure
was to replace all them.



--
"I am a river to my people."
Jeff-1.0
WA6FWi
http:foxsmercantile.com

Cursitor Doom

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Nov 10, 2019, 10:20:06 AM11/10/19
to
On Sun, 10 Nov 2019 05:59:39 -0800, Michael Terrell wrote:

> The capacitors on the AC line input crack and adsorb moisture, Then the
> explode, along with the smell of burning plastic. They are a common
> failure in older HP test equipment. Once the short clears, the equipment
> will operate, but not in a safe manor. Most people replace the entire
> filter, rather than the capacitors. The ones that fail are mostly the
> same brand.

Thanks for that, Michael. I think I've found the cap you refer to,
straddled across the mains incoming supply, looking rather jaded, bulgy
and cracked. I'd have thought they'd have used potted, integrated filters
like the Tek scopes of the same era did. I think IIRC I've had issues
with these caps before on other equipment. It's buried somewhat in the
guts of the device immediately behind the mains socket but I can just
about see it. 250V it says on it. Not much headroom with our 240V mains
here!
How about I just snip it out and not bother replacing it? It's a PITA to
get at.

Fox's Mercantile

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Nov 10, 2019, 10:24:43 AM11/10/19
to
On 11/10/19 9:20 AM, Cursitor Doom wrote:
> How about I just snip it out and not bother replacing it?
> It's a PITA to get at.

Or you could just throw it in the trash. If it's not worth
fixing, it's not worth keeping.

Michael Terrell

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Nov 10, 2019, 10:27:06 AM11/10/19
to
On Sunday, November 10, 2019 at 10:20:06 AM UTC-5, Cursitor Doom wrote:
> On Sun, 10 Nov 2019 05:59:39 -0800, Michael Terrell wrote:
>
> > The capacitors on the AC line input crack and adsorb moisture, Then the
> > explode, along with the smell of burning plastic. They are a common
> > failure in older HP test equipment. Once the short clears, the equipment
> > will operate, but not in a safe manor. Most people replace the entire
> > filter, rather than the capacitors. The ones that fail are mostly the
> > same brand.
>
> Thanks for that, Michael. I think I've found the cap you refer to,
> straddled across the mains incoming supply, looking rather jaded, bulgy
> and cracked. I'd have thought they'd have used potted, integrated filters
> like the Tek scopes of the same era did. I think IIRC I've had issues
> with these caps before on other equipment. It's buried somewhat in the
> guts of the device immediately behind the mains socket but I can just
> about see it. 250V it says on it. Not much headroom with our 240V mains
> here!
> How about I just snip it out and not bother replacing it? It's a PITA to
> get at.

They are X or Y rated safety capacitors. I would not omit them. The 250 volt marking is AC volts, not DC. The HP manual should have the specs for the bad caps.

Michael Terrell

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Nov 10, 2019, 10:29:51 AM11/10/19
to
On Sunday, November 10, 2019 at 9:37:30 AM UTC-5, Fox's Mercantile wrote:
> On 11/10/19 7:59 AM, Michael Terrell wrote:
> > The capacitors on the AC line input crack and adsorb moisture,
> > Then the explode, along with the smell of burning plastic.
> > They are a common failure in older HP test equipment.
>
> I used to repair test equipment at Hughes Aircraft.
> I was surprised to find that HP used Sprague Black Beauty
> capacitors in their older equipment.
> Regardless of the reason it was on the bench, standard procedure
> was to replace all them.

Just think of all the Ebay sales you could have made to deluded musicians, with those used BB caps! come to think of it, I had a bag of NOS BBs that came from an old shop that went out of business. Maybe I'll dig them out and list them. :)

Michael Terrell

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Nov 10, 2019, 10:31:54 AM11/10/19
to
On Sunday, November 10, 2019 at 10:24:43 AM UTC-5, Fox's Mercantile wrote:
> On 11/10/19 9:20 AM, Cursitor Doom wrote:
> > How about I just snip it out and not bother replacing it?
> > It's a PITA to get at.
>
> Or you could just throw it in the trash. If it's not worth
> fixing, it's not worth keeping.

Have you seen the 'Nano VNA' handheld units? Under $50 at many places.

Cursitor Doom

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Nov 10, 2019, 10:34:57 AM11/10/19
to
On Sun, 10 Nov 2019 07:27:03 -0800, Michael Terrell wrote:

> They are X or Y rated safety capacitors. I would not omit them. The 250
> volt marking is AC volts, not DC. The HP manual should have the specs
> for the bad caps.

I have a box full of Wima X and Y caps here (which are supposed to be
superior) so sourcing a replacement for this failed Rifa is not an issue.
It's getting access that's the thing.

Michael Terrell

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Nov 10, 2019, 11:14:39 AM11/10/19
to
On Sunday, November 10, 2019 at 10:34:57 AM UTC-5, Cursitor Doom wrote:
> On Sun, 10 Nov 2019 07:27:03 -0800, Michael Terrell wrote:
>
> > They are X or Y rated safety capacitors. I would not omit them. The 250
> > volt marking is AC volts, not DC. The HP manual should have the specs
> > for the bad caps.
>
> I have a box full of Wima X and Y caps here (which are supposed to be
> superior) so sourcing a replacement for this failed Rifa is not an issue.
> It's getting access that's the thing.

What's life, without a challenge? :)

Cursitor Doom

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Nov 10, 2019, 11:19:15 AM11/10/19
to
On Sun, 10 Nov 2019 07:27:03 -0800, Michael Terrell wrote:

> They are X or Y rated safety capacitors. I would not omit them.

They're "safety capacitors" in respect of the fact that they can be
connected across a (reasonably) high energy source; that's all. If they
are omitted it's NOT a safety issue. Obviously *if* one is going to
connect a capacitor across the mains supply it needs to be X rated, but
*leaving out* such a capacitor, x rated or not, is not going to kill or
injure anyone.

Mike

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Nov 10, 2019, 11:22:04 AM11/10/19
to
In article <qq99r3$lps$1...@dont-email.me>,
Cursitor Doom <cu...@notformail.com> wrote:
>like the Tek scopes of the same era did. I think IIRC I've had issues
>with these caps before on other equipment.

Elsewhere down thread you mention "RIFA" capacitors, sounds like the
gold coloured 0.47uF/250V ones that seem to disgrace various 1980's
ASTEC branded power supplies (BBC Computer, Apple II computer, ICL
One Per Desk and others) all of which work fine for a while, and then
crackle-phut-burnt toffee flavoured smoke, but keep on working.

I guess I got lucky, they didn't fail shorted, but they definitely
cracked and bulged.


--
--------------------------------------+------------------------------------
Mike Brown: mjb[-at-]signal11.org.uk | http://www.signal11.org.uk

Ralph Mowery

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Nov 10, 2019, 11:24:08 AM11/10/19
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In article <0673dcfc-6859-4f94...@googlegroups.com>,
terrell....@gmail.com says...
>
> Have you seen the 'Nano VNA' handheld units? Under $50 at many places.
>
>

I bought one a while back and paid $ 57 for it. They have came down.

While not lab quality, they do work well enough for an expirmenter on a
low budget.

Around 20 years or less ago , they would almost have been lab quality.
All they would need is a high stable and accurate frequency .

There is lots of stuff comming out of China that works well enough for
people like me that don't have a lot of money to buy things with but
still like to expirment and learn.

Those little component testers for around $ 20 really get to me. They
seem to work really well in most cases as to identifying components and
their values.

Cursitor Doom

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Nov 10, 2019, 11:54:24 AM11/10/19
to
On Sun, 10 Nov 2019 08:14:36 -0800, Michael Terrell wrote:

> What's life, without a challenge? :)

A challenge has to be, by definition, ultimately achievable. Removing
this cap is *not* achievable. I would have to destroy the entire VNA to
get it out. What a rotten design.

Michael Terrell

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Nov 10, 2019, 12:56:31 PM11/10/19
to
On Sunday, November 10, 2019 at 11:24:08 AM UTC-5, Ralph Mowery wrote:
>
> Michael Terrell says...
> >
> > Have you seen the 'Nano VNA' handheld units? Under $50 at many places.
>
> I bought one a while back and paid $ 57 for it. They have came down.
>
> While not lab quality, they do work well enough for an experimenter on a
> low budget.
>
> Around 20 years or less ago , they would almost have been lab quality.
> All they would need is a high stable and accurate frequency .
>
> There is lots of stuff coming out of China that works well enough for
> people like me that don't have a lot of money to buy things with but
> still like to experiment and learn.
>
> Those little component testers for around $ 20 really get to me. They
> seem to work really well in most cases as to identifying components and
> their values.

I bought a Nano VNA for $42.87 with some Ebay bucks that were about to expire, but I haven't tried it yet. I am currently trying to get another door and a handicap ramp installed at my home. The current exits all have too many steps to go up and down. I haven't been in my shop building for several years, because it is too much pain to get out to it, and stand at the workbench. Once the modifications are done, I will have room for a small bench in that room.

I am retired, so I no longer have access to the multiple workbenches of test equipment that I used on my last job.

I agree about those component testers being useful. I have a couple. Another one that is handy is a $10 VGA monitor test generator.


Michael Terrell

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Nov 10, 2019, 12:58:24 PM11/10/19
to
On Sunday, November 10, 2019 at 11:19:15 AM UTC-5, Cursitor Doom wrote:
> On Sun, 10 Nov 2019 07:27:03 -0800, Michael Terrell wrote:
>
> > They are X or Y rated safety capacitors. I would not omit them.
>
> They're "safety capacitors" in respect of the fact that they can be
> connected across a (reasonably) high energy source; that's all. If they
> are omitted it's NOT a safety issue. Obviously *if* one is going to
> connect a capacitor across the mains supply it needs to be X rated, but
> *leaving out* such a capacitor, x rated or not, is not going to kill or
> injure anyone.

X capacitors are to filter RF from the power lines. Y capacitors are for safety.

Michael Terrell

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Nov 10, 2019, 1:00:13 PM11/10/19
to
On Sunday, November 10, 2019 at 11:54:24 AM UTC-5, Cursitor Doom wrote:
> On Sun, 10 Nov 2019 08:14:36 -0800, Michael Terrell wrote:
>
> > What's life, without a challenge? :)
>
> A challenge has to be, by definition, ultimately achievable. Removing
> this cap is *not* achievable. I would have to destroy the entire VNA to
> get it out. What a rotten design.

Those plastic capacitors were supposed to be high rel, but they didn't expect the cases to craze, and fail. What model is your VNA?

Cursitor Doom

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Nov 10, 2019, 2:22:02 PM11/10/19
to
On Sun, 10 Nov 2019 10:00:10 -0800, Michael Terrell wrote:

> Those plastic capacitors were supposed to be high rel, but they didn't
> expect the cases to craze, and fail. What model is your VNA?

It's the 8754A. It tops out at 1.3Ghz which was, a long time ago when I
purchased it, was a respectably high frequency! In fact it's still the
highest practicable frequency band allocated for radio hams, which was
another good reason for me to choose it.

Cursitor Doom

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Nov 10, 2019, 2:35:20 PM11/10/19
to
On Sun, 10 Nov 2019 09:58:21 -0800, Michael Terrell wrote:

> X capacitors are to filter RF from the power lines. Y capacitors are for
> safety.

I suspect you're going to have a few contradictory views about that
sweeping statement from some of our not-so-polite regulars here! ;-)

I can *just* access enough to snip the blown cap out and discard it. I
think I'll fit a new one to the end of the power lead instead; it's my
only option realistically.

John-Del

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Nov 10, 2019, 5:30:42 PM11/10/19
to
On Sunday, November 10, 2019 at 10:20:06 AM UTC-5, Cursitor Doom wrote:
> On Sun, 10 Nov 2019 05:59:39 -0800, Michael Terrell wrote:
>
> > The capacitors on the AC line input crack and adsorb moisture, Then the
> > explode, along with the smell of burning plastic. They are a common
> > failure in older HP test equipment. Once the short clears, the equipment
> > will operate, but not in a safe manor. Most people replace the entire
> > filter, rather than the capacitors. The ones that fail are mostly the
> > same brand.
>
> Thanks for that, Michael. I think I've found the cap you refer to,
> straddled across the mains incoming supply, looking rather jaded, bulgy
> and cracked.


But did it cause a bang loud enough to be heard in a shower?

I had a TV do that back in the 80s, and what it did was launch an electrolytic clean off the board. I found some paper packing and eventually the cap itself. The TV still worked and the only evidence left on the board was two very clean leads where the cap used to sit.

Even though you found a pretty good suspect, I'd look the rest of it over very carefully for a couple of leads and no part between them.


Michael Terrell

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Nov 10, 2019, 5:41:51 PM11/10/19
to
On Sunday, November 10, 2019 at 2:22:02 PM UTC-5, Cursitor Doom wrote:
> On Sun, 10 Nov 2019 10:00:10 -0800, Michael Terrell wrote:
>
> > Those plastic capacitors were supposed to be high rel, but they didn't
> > expect the cases to craze, and fail. What model is your VNA?
>
> It's the 8754A. It tops out at 1.3Ghz which was, a long time ago when I
> purchased it, was a respectably high frequency! In fact it's still the
> highest practicable frequency band allocated for radio hams, which was
> another good reason for me to choose it.

The only manual that I have only covers operation, but it is dated 1978. The design life was typically 15 to 20 years at that time, so it lasted twice that time. It does show the IEC power connector and voltage selector on the rear panel. That is where the line filter should be. It looks like it might be a Corcom 6J4 Power Entry Module. That 6J series is available with and without a filter.

Michael Terrell

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Nov 10, 2019, 5:51:19 PM11/10/19
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I had a HP desktop computer lose an electrolytic capacitor in the power supply. The can blew out through the fan, along with flames.

I've had the large (160uF, 250V input capacitor in a v0ltage doubler explode in a TV while it was on the workbench. Confetti for about 20' radius. :)

I had just installed a new amplifier in a car dealership. They called the next day that t had a loud hum. Lightning had hit the early Japanese business telephone system's optional paging adapter. It blew the cover off the metal box, and it was another mess of confetti all over the old telephone equipment room. They replaced it, and that one exploded a week later. Neither design had any surge protection. Both times, their neighborhood was hit with 100W of 60Hz hum and other noise from the PA horns in their used car lot.. ;-)

Cursitor Doom

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Nov 10, 2019, 6:14:36 PM11/10/19
to
On Sun, 10 Nov 2019 14:30:39 -0800, John-Del wrote:

Me:

>> Thanks for that, Michael. I think I've found the cap you refer to,
>> straddled across the mains incoming supply, looking rather jaded, bulgy
>> and cracked.
>
>
> But did it cause a bang loud enough to be heard in a shower?

We're assuming it was this X cap as it's clearly damaged, but I admit I
would expect from the bang (which I did hear *whilst* in the shower 30'
feet away) I'd have expected to see more extreme damage to that cap than
I did.

> I had a TV do that back in the 80s, and what it did was launch an
> electrolytic clean off the board. I found some paper packing and
> eventually the cap itself. The TV still worked and the only evidence
> left on the board was two very clean leads where the cap used to sit.
>
> Even though you found a pretty good suspect, I'd look the rest of it
> over very carefully for a couple of leads and no part between them.

You're right. I need to eliminate the possibility that the x-cap damage
had maybe been there since years ago and I still haven't found the true
culprit. If that may be the case, then what other part from where could
account for it? I've already eliminated the big electrolytics from
suspicion.

Fox's Mercantile

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Nov 10, 2019, 6:33:20 PM11/10/19
to
On 11/10/19 5:14 PM, Cursitor Doom wrote:
> I need to eliminate the possibility that the x-cap damage
> had maybe been there since years ago and I still haven't
> found the true culprit.

Capacitors across the power line, when they fail, they fail
spectacularly. And usually fast enough that they don't always
take out the line fuse.

This is why they make X caps. When they fail they, in addition
to failing short, they don't explode with a vengeance or set
fire to themselves or the surrounding bits.

Y caps, on the other hand, go from the line, or neutral to
ground. They are designed to fail open.

<https://www.allaboutcircuits.com/technical-articles/safety-capacitor-class-x-and-class-y-capacitors/>

Cursitor Doom

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Nov 10, 2019, 6:43:21 PM11/10/19
to
On Sun, 10 Nov 2019 14:41:48 -0800, Michael Terrell wrote:

> The only manual that I have only covers operation, but it is dated 1978.
> The design life was typically 15 to 20 years at that time, so it lasted
> twice that time. It does show the IEC power connector and voltage
> selector on the rear panel. That is where the line filter should be. It
> looks like it might be a Corcom 6J4 Power Entry Module. That 6J series
> is available with and without a filter.

This one has no mains filter AFAICS; just that busted cap. I do have the
*full* service and operating manual so I'll take a look and see what that
says tomorrow as it takes a month of sundays to find anything I need in
it. But like I say, if there *is* a filter, it's going to be nano-sized
and next to useless.

Cursitor Doom

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Nov 10, 2019, 7:50:14 PM11/10/19
to
On Sun, 10 Nov 2019 17:32:51 -0600, Fox's Mercantile wrote:

> Capacitors across the power line, when they fail, they fail
> spectacularly. And usually fast enough that they don't always take out
> the line fuse.
>
> This is why they make X caps. When they fail they, in addition to
> failing short, they don't explode with a vengeance or set fire to
> themselves or the surrounding bits.

You seem to be contradicting yourself in the second paragraph. You
initially say "they fail spectacularly" then you say, "they don't explode
with a vengeance". It can't be both, so which is it?

Fox's Mercantile

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Nov 10, 2019, 8:33:44 PM11/10/19
to
On 11/10/19 6:50 PM, Cursitor Doom wrote:
> On Sun, 10 Nov 2019 17:32:51 -0600, Fox's Mercantile wrote:
>
>> Capacitors across the power line, when they fail, they fail
>> spectacularly. And usually fast enough that they don't always take out
>> the line fuse.
>>
>> This is why they make X caps. When they fail they, in addition to
>> failing short, they don't explode with a vengeance or set fire to
>> themselves or the surrounding bits.
>
> You seem to be contradicting yourself in the second paragraph. You
> initially say "they fail spectacularly" then you say, "they don't explode
> with a vengeance". It can't be both, so which is it?

Capacitors, NOT X rated.

Vs X rated.

Cursitor Doom

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Nov 10, 2019, 8:44:06 PM11/10/19
to
On Sun, 10 Nov 2019 19:33:18 -0600, Fox's Mercantile wrote:

> Capacitors, NOT X rated.
>
> Vs X rated.

So you're saying the x-cap that looks like the culprit can't be, then?
Maybe you're right; we'll see in due course....

Michael Terrell

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Nov 10, 2019, 9:37:45 PM11/10/19
to
On Sunday, November 10, 2019 at 7:50:14 PM UTC-5, Cursitor Doom wrote:
> On Sun, 10 Nov 2019 17:32:51 -0600, Fox's Mercantile wrote:
>
> > Capacitors across the power line, when they fail, they fail
> > spectacularly. And usually fast enough that they don't always take out
> > the line fuse.
> >
> > This is why they make X caps. When they fail they, in addition to
> > failing short, they don't explode with a vengeance or set fire to
> > themselves or the surrounding bits.
>
> You seem to be contradicting yourself in the second paragraph. You
> initially say "they fail spectacularly" then you say, "they don't explode
> with a vengeance". It can't be both, so which is it?


They are designed to burn away the short, so there is no contradiction. The foil is very thin, so it vaporizes away from the point of failure, leaving the remaining part of the capacitor, in circuit. If you measure the capacitance of a damaged X or Y capacitor, it will be lower than marked.

Fox's Mercantile

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Nov 10, 2019, 10:30:29 PM11/10/19
to
On 11/10/19 7:44 PM, Cursitor Doom wrote:
> On Sun, 10 Nov 2019 19:33:18 -0600, Fox's Mercantile wrote:
>
>> Capacitors, NOT X rated.
>>
>> Vs X rated.
>
> So you're saying the x-cap that looks like the culprit can't be, then?
> Maybe you're right; we'll see in due course....

Oh for fuck's sake.
X rated capacitors are a recent development.
There weren't any when HP built the VNAs.
They used standard capacitors at the time. Like everyone else.
Which, is why, when it failed, it failed spectacularly.

John-Del

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Nov 11, 2019, 7:48:46 AM11/11/19
to
On Sunday, November 10, 2019 at 6:33:20 PM UTC-5, Fox's Mercantile wrote:
> On 11/10/19 5:14 PM, Cursitor Doom wrote:
> > I need to eliminate the possibility that the x-cap damage
> > had maybe been there since years ago and I still haven't
> > found the true culprit.
>
> Capacitors across the power line, when they fail, they fail
> spectacularly. And usually fast enough that they don't always
> take out the line fuse.

Back in the mid to late 60s, RCA used a .1uf cap right across the AC interlock. They would let go on occasion and fail, well, spectacularly. They would blast bits of metal and tons of carbon under the whole chassis. Because they were wired before the breaker, they kept going until the house fuse blew or they spent their mass.

RCA recalled them and I remember putting in several hundred replacement caps through the 70s. Back then, most TVs weren't registered with the manufacturer and without internet, it was difficult getting consumers aware of the issue. But whenever we'd see one (dark brown), we'd automatically replace it with the revised cap.

Cursitor Doom

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Nov 11, 2019, 11:25:42 AM11/11/19
to
On Mon, 11 Nov 2019 04:48:42 -0800, John-Del wrote:

> Back in the mid to late 60s, RCA used a .1uf cap right across the AC
> interlock. They would let go on occasion and fail, well, spectacularly.
> They would blast bits of metal and tons of carbon under the whole
> chassis.

Hmmm. Amazing a little .1uF cap could make that much noise! I freely
admit I've never been in the same room when a cap let-go, so have only
ever heard them from some way off. I really should blow some up on
purpose so I know for myself; that's an essential part of my education
that's been missing all these years.
Is the violence you get commensurate with the capacity? Say for example I
blow up a 10,000uF electrolytic on purpose, is it a *much* bigger deal
than say a 25uF one? What does the noise approximate to - as much as a
pistol shot?

amdx

unread,
Nov 11, 2019, 12:11:39 PM11/11/19
to
I caution others to research before you buy, some work great others
have a higher failure rate and the external appearance seems to be a
clue. The one I saw recommended has a white front with a lizard climbing
down on the right side. But,people do like them, there are several
groups running about the Nano VNA and new open source software being
written.
Mikek

Mike Coon

unread,
Nov 11, 2019, 2:56:39 PM11/11/19
to
In article <qqc220$9r7$1...@dont-email.me>, cu...@notformail.com says...
>
> Hmmm. Amazing a little .1uF cap could make that much noise! I freely
> admit I've never been in the same room when a cap let-go, so have only
> ever heard them from some way off. I really should blow some up on
> purpose so I know for myself; that's an essential part of my education
> that's been missing all these years.
> Is the violence you get commensurate with the capacity? Say for example I
> blow up a 10,000uF electrolytic on purpose, is it a *much* bigger deal
> than say a 25uF one? What does the noise approximate to - as much as a
> pistol shot?

It must have been in 1961 when I had a holiday job bewteen school and
college at a local PA manufacturer. I was present when the snooty
designer came to appraise the prototype of a new model. He was peering
at the build detail when an electrolytic exploded. I don't remember the
capacity or much noise, but the confetti of foil draped over him caused
a lot of bitten lips while the audience suppressed their giggles...

Mike.

tabb...@gmail.com

unread,
Nov 11, 2019, 3:15:57 PM11/11/19
to
On Sunday, 10 November 2019 15:20:06 UTC, Cursitor Doom wrote:
> On Sun, 10 Nov 2019 05:59:39 -0800, Michael Terrell wrote:
>
> > The capacitors on the AC line input crack and adsorb moisture, Then the
> > explode, along with the smell of burning plastic. They are a common
> > failure in older HP test equipment. Once the short clears, the equipment
> > will operate, but not in a safe manor. Most people replace the entire
> > filter, rather than the capacitors. The ones that fail are mostly the
> > same brand.
>
> Thanks for that, Michael. I think I've found the cap you refer to,
> straddled across the mains incoming supply, looking rather jaded, bulgy
> and cracked. I'd have thought they'd have used potted, integrated filters
> like the Tek scopes of the same era did. I think IIRC I've had issues
> with these caps before on other equipment. It's buried somewhat in the
> guts of the device immediately behind the mains socket but I can just
> about see it. 250V it says on it. Not much headroom with our 240V mains
> here!
> How about I just snip it out and not bother replacing it? It's a PITA to
> get at.

240v is 330v peak, so no headroom at all.


NT

tabb...@gmail.com

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Nov 11, 2019, 3:18:16 PM11/11/19
to
On Sunday, 10 November 2019 16:54:24 UTC, Cursitor Doom wrote:
> On Sun, 10 Nov 2019 08:14:36 -0800, Michael Terrell wrote:
>
> > What's life, without a challenge? :)
>
> A challenge has to be, by definition, ultimately achievable. Removing
> this cap is *not* achievable. I would have to destroy the entire VNA to
> get it out. What a rotten design.

Just snip it then, it's not needed.


NT

Fox's Mercantile

unread,
Nov 11, 2019, 4:10:58 PM11/11/19
to
Spoken like a true hack.

tabb...@gmail.com

unread,
Nov 11, 2019, 5:01:10 PM11/11/19
to
On Monday, 11 November 2019 21:10:58 UTC, Fox's Mercantile wrote:
> On 11/11/19 2:18 PM, tabbypurr wrote:
> > On Sunday, 10 November 2019 16:54:24 UTC, Cursitor Doom wrote:
> >> On Sun, 10 Nov 2019 08:14:36 -0800, Michael Terrell wrote:
> >>
> >>> What's life, without a challenge? :)
> >>
> >> A challenge has to be, by definition, ultimately achievable. Removing
> >> this cap is *not* achievable. I would have to destroy the entire VNA to
> >> get it out. What a rotten design.
> >
> > Just snip it then, it's not needed.
> >
> >
> > NT
> >
>
> Spoken like a true hack.

are you being childish again?

peterw...@gmail.com

unread,
Nov 11, 2019, 5:15:22 PM11/11/19
to
The bean counters would never let an unnecessary part into any design. Therefore, leaving a part out of a design is "hack".

That is, unless one is Mad Man Muntz.

Peter Wieck
Melrose Park, PA

Clifford Heath

unread,
Nov 11, 2019, 5:25:42 PM11/11/19
to
On 12/11/19 3:25 am, Cursitor Doom wrote:
> Is the violence you get commensurate with the capacity? Say for example I
> blow up a 10,000uF electrolytic on purpose, is it a *much* bigger deal
> than say a 25uF one? What does the noise approximate to - as much as a
> pistol shot?
The larger cap will likely make less noise. The metal can will have
similar wall thickness, but much greater circumference, so the hoop
stress will be much bigger - it will split down one side under much less
internal pressure.

Small diameter, large C (meaning low voltage), low ESR, will make the
biggest bang.

Clifford Heath

Fox's Mercantile

unread,
Nov 11, 2019, 5:33:21 PM11/11/19
to
In your dreams kid.
I take pride in my service and repairs.
If it's "difficult" it gets done anyway.

If it's buried, I remove what has to be removed to get access to it.
And the old leads get removed, the terminal gets cleaned and new
part gets soldered in just like "factory original;."
Then the removed parts get put back in place.

It's not that complicated to understand "doing it right."

Phil Allison

unread,
Nov 11, 2019, 7:02:07 PM11/11/19
to
Fox's Mercantile wrote:

---------------------------
>
>
> Capacitors across the power line, when they fail, they fail
> spectacularly. And usually fast enough that they don't always
> take out the line fuse.
>
> This is why they make X caps. When they fail they, in addition
> to failing short, they don't explode with a vengeance or set
> fire to themselves or the surrounding bits.
>

** Fraid X caps do fail spectacularly.

With tons of smoke and bits flying a well.

On two occasions, I have been in the same room at the time and had it filled with acrid smoke.

Wima X2 types both times, but others are really no better.

Hot environments make it happen sooner, IME.

X2 caps are "double wound" effectively two is series to avoid internal corona that occurs across microscopic internal air gaps.

Y caps are often ceramic or wound "in vacuo" to avoids the issue.


.... Phil


John-Del

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Nov 11, 2019, 7:13:04 PM11/11/19
to
On Monday, November 11, 2019 at 11:25:42 AM UTC-5, Cursitor Doom wrote:
> On Mon, 11 Nov 2019 04:48:42 -0800, John-Del wrote:
>
> > Back in the mid to late 60s, RCA used a .1uf cap right across the AC
> > interlock. They would let go on occasion and fail, well, spectacularly.
> > They would blast bits of metal and tons of carbon under the whole
> > chassis.
>
> Hmmm. Amazing a little .1uF cap could make that much noise! I freely
> admit I've never been in the same room when a cap let-go, so have only
> ever heard them from some way off. I really should blow some up on
> purpose so I know for myself; that's an essential part of my education
> that's been missing all these years.
> Is the violence you get commensurate with the capacity? Say for example I
> blow up a 10,000uF electrolytic on purpose, is it a *much* bigger deal
> than say a 25uF one? What does the noise approximate to - as much as a
> pistol shot?
>
>

Let me clarify that these RCA line caps were film caps and did not go off like a gunshot like shorted electros do. I would say the sound they made was over several seconds or even minutes and would likely have sounded more like a piece of metal shoved into a bench grinder.

I mentioned a story I might relate earlier in the thread, and here it is: I was doing a house call back in the early 70s with my dad. It was a low end metal cabinet Sylvania hybrid (tube/transistor) that had a tripped breaker.

The breaker was old and creaky and wouldn't reset, so my dad gave it a couple of whacks with the back the nutdriver he used to remove the back. The breaker went in and the TV lit up, but it was dark, shrunk on the sides, rippling, and making a loud hum. Just as my dad was explaining to the customer that it would need a filter (multi segment chassis mounted can electro) we heard a loud hiss for a couple of seconds and before we could pull the cord out, the can electro blew the aluminum cylinder off with the sound of a gunshot. The room was immediately filled with an acrid gray smoke and the people bailed out of the house in a hurry.

The can let go with such force that it actually left a clean circle imprinted upwards in the metal cabinet. Given that the filter housing was lightweight aluminum and given how far it indented the heavy steel cabinet, it must have been launched with impressive speed.

The customer did not want the TV even though it only needed a filter and breaker, and we brought them a new Zenith the next day.

Cursitor Doom

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Nov 11, 2019, 7:15:49 PM11/11/19
to
On Mon, 11 Nov 2019 16:32:39 -0600, Fox's Mercantile wrote:

> If it's buried, I remove what has to be removed to get access to it.
> And the old leads get removed, the terminal gets cleaned and new part
> gets soldered in just like "factory original;."
> Then the removed parts get put back in place.

This mains inlet module requires some special service tool to be able to
withdraw it from rear. THEN you get full, unobstructed access to the
capacitor in question. Unfortunately, I don't possess that tool.

Cursitor Doom

unread,
Nov 11, 2019, 7:27:21 PM11/11/19
to
On Mon, 11 Nov 2019 12:15:53 -0800, tabbypurr wrote:

> 240v is 330v peak, so no headroom at all.

Well, quite. So I'm wondering if those caps have a different convention
to others in their voltage ratings. Perhaps in the case of x-caps, that
"250V" essentially means:

"This cap is designed to cope with European voltage levels and is safe to
use across UK mains of the range 220-250V and brief transients vastly in
excess of this limit can also be accommodated."

Just my 2p worth.....

Michael Terrell

unread,
Nov 12, 2019, 6:23:03 AM11/12/19
to
On Monday, November 11, 2019 at 7:15:49 PM UTC-5, Cursitor Doom wrote:
> On Mon, 11 Nov 2019 16:32:39 -0600, Fox's Mercantile wrote:
>
> > If it's buried, I remove what has to be removed to get access to it.
> > And the old leads get removed, the terminal gets cleaned and new part
> > gets soldered in just like "factory original;."
> > Then the removed parts get put back in place.
>
> This mains inlet module requires some special service tool to be able to
> withdraw it from rear. THEN you get full, unobstructed access to the
> capacitor in question. Unfortunately, I don't possess that tool.

A special tool? if it is a snap in type, all you need are a couple screwdrivers. One to depress the tabs, an another to push against the body. Work one end then the other until it pops free. I've removed hundreds of them, that way from scrapped computer terminals.

tabb...@gmail.com

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Nov 12, 2019, 10:44:45 PM11/12/19
to
Damn, where have you been hiding for half a century? I recently watched a small populated PCB snipped out of a hoover, ran perfectly afterwards. Years ago I removed nearly all of an entire PCB from a Sony TV, it worked afterwards. A big complex psu pcb. A huge proportion of e-stuff has bits in it doesn't need. There's an assortment of reasons why. I don't see how you could design stuff without knowing that.


NT

tabb...@gmail.com

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Nov 12, 2019, 10:46:55 PM11/12/19
to
On Monday, 11 November 2019 22:33:21 UTC, Fox's Mercantile wrote:
That approach is the right one for mil spec kit repairs. It is inappropriate for domestic kit.


NT

tabb...@gmail.com

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Nov 12, 2019, 10:50:53 PM11/12/19
to
I'd appreciate it if I could email you briefly about this. Is there some way to?


NT

tabb...@gmail.com

unread,
Nov 12, 2019, 10:52:05 PM11/12/19
to
On Tuesday, 12 November 2019 00:27:21 UTC, Cursitor Doom wrote:
> On Mon, 11 Nov 2019 12:15:53 -0800, tabbypurr wrote:
>
> > 240v is 330v peak, so no headroom at all.
>
> Well, quite. So I'm wondering if those caps have a different convention
> to others in their voltage ratings. Perhaps in the case of x-caps, that
> "250V" essentially means:
>
> "This cap is designed to cope with European voltage levels and is safe to
> use across UK mains of the range 220-250V and brief transients vastly in
> excess of this limit can also be accommodated."
>
> Just my 2p worth.....

Oh, if they're x caps they're normally an ac rating.


NT

Fox's Mercantile

unread,
Nov 13, 2019, 4:18:14 AM11/13/19
to
Like I said, you're a hack.

Cursitor Doom

unread,
Nov 14, 2019, 6:42:53 PM11/14/19
to
On Sun, 10 Nov 2019 18:37:41 -0800, Michael Terrell wrote:

> They are designed to burn away the short, so there is no contradiction.
> The foil is very thin, so it vaporizes away from the point of failure,
> leaving the remaining part of the capacitor, in circuit. If you measure
> the capacitance of a damaged X or Y capacitor, it will be lower than
> marked.

Yeah, I guess it would. Anyway, after hacking a hole in the bottom of the
motherboard I was able to removed the cap in question from underneath and
it looks far worse now I can see it properly. It definitely let go in a
big way and now I'm pretty confident it was the source of the loud bang I
heard. I've also carefully examined all the other sub-boards and the PCB
underneath them and they're all fine. Shards of broken cap were scattered
about the area of the explosion. Shame I had to butcher the board to get
it out, but there was no other way open to me. I follow what you said
about removing that j6 power connector but I just don't have the
dexterity I'm afraid. So it was a case of Dremmel to the rescue! :-)

tabb...@gmail.com

unread,
Nov 21, 2019, 2:00:31 PM11/21/19
to
On Wednesday, 13 November 2019 09:18:14 UTC, Fox's Mercantile wrote:
like I said you're childish.

Fox's Mercantile

unread,
Nov 21, 2019, 4:49:46 PM11/21/19
to
That's your opinion.
My opinion is that you're hack.

Cursitor Doom

unread,
Nov 22, 2019, 4:22:43 AM11/22/19
to
On Thu, 21 Nov 2019 15:49:38 -0600, Fox's Mercantile wrote:

> My opinion is that you're hack.

My opinion is you're Phil Alison and ICTFP.

Fox's Mercantile

unread,
Nov 22, 2019, 5:22:15 AM11/22/19
to
On 11/22/19 3:22 AM, Cursitor Doom wrote:
> On Thu, 21 Nov 2019 15:49:38 -0600, Fox's Mercantile wrote:
>
>> My opinion is that you're hack.
>
> My opinion is you're Phil Alison and ICTFP.

Oh look, the hacks are circling the wagons.

tabb...@gmail.com

unread,
Nov 22, 2019, 6:30:34 AM11/22/19
to
On Thursday, 21 November 2019 21:49:46 UTC, Fox's Mercantile wrote:
heh. you said that already.

Jeff Liebermann

unread,
Nov 22, 2019, 10:54:56 AM11/22/19
to
On Sun, 10 Nov 2019 13:37:34 -0000 (UTC), Cursitor Doom
<cu...@notformail.com> wrote:

>No visible signs inside what could have catastrophically
>failed, just the unmistakable smell that *something* has. The device
>still powers up fine and the screen traces are normal, so wtf else goes
>*bang* and smells toxic?

You seem to be floundering:

1. Are you sure that it was the HP VNA that blew a capacitor or
something? When you removed the case, was it lit up?

2. Toxic smells tend to be cause by vaporized electrolye. That
leaves a messy stain which should have been present. If you can't see
the damage, perhaps playing bloodhound and smelling for the damage
might help. Find a vinyl hose, cram it into your nose, and sniff
around the VNA and the shop for the strongest smell. Unless you use
an air freshener (nasal desensitize), you should be able to find the
source many days after it went bang.

3. When you tested the electrolytics, did you use both an ESR meter
and a capacitance meter? If the ESR meter doesn't show a problem, the
capacitance meter might.

4. Do you have a UV LED flashlight? When tracking down bulging
electrolytic problems on computah motherboards, I sometimes (not
always) can seen the electrolyte residue using a UV flashlight.

5. Did you have the AC power switch set for 230VAC or 117VAC?

6. Check if the small is coming from a power strip. The MOV's
sometimes go bang.

Argh, gotta run...
--
Jeff Liebermann je...@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Cursitor Doom

unread,
Nov 22, 2019, 8:37:39 PM11/22/19
to
On Fri, 22 Nov 2019 07:54:53 -0800, Jeff Liebermann wrote:

> 1. Are you sure that it was the HP VNA that blew a capacitor or
> something? When you removed the case, was it lit up?

Thank you, Jeffrey. Not sure if you were able to read the thread right
through, but it's been established that the blown cap was an X2 rated one
fitted right across the incoming mains power line. It took a while to
confirm this was the actual culprit as it was well buried under a load of
spaghetti. When I finally got it out I was able to see it had literally
exploded which accounts for the report I heard from 30' away.
That cap has now been replaced and the device appears to be working fine
again, although after 10 years of storage there's no doubt some re-
aligning and whatnot to be done.

Cursitor Doom

unread,
Nov 22, 2019, 8:40:11 PM11/22/19
to
On Fri, 22 Nov 2019 04:22:06 -0600, Fox's Mercantile wrote:

> On 11/22/19 3:22 AM, Cursitor Doom wrote:
>> On Thu, 21 Nov 2019 15:49:38 -0600, Fox's Mercantile wrote:
>>
>>> My opinion is that you're hack.
>>
>> My opinion is you're Phil Alison and ICTFP.
>
> Oh look, the hacks are circling the wagons.

You can call me a hack as well if you like; I couldn't give a shit TBH.
I'm not very practical. I get the job done but it doesn't look as pretty
as some genius like yourself would leave it. But do I care? Nope! Because
the case goes back on and no one can see it anyway.

Fox's Mercantile

unread,
Nov 22, 2019, 9:11:38 PM11/22/19
to
On 11/22/19 7:40 PM, Cursitor Doom wrote:
> You can call me a hack as well if you like;

I did.

> I couldn't give a shit TBH.

Actually, that's not true. If you honestly didn't
give a shit, you wouldn't have wasted the time to
defend yourself.

> I'm not very practical.
This too is obvious.

> But do I care? Nope! Because the case goes back on
> and no one can see it anyway.

No, of course you don't care. That's because you have
zero pride in your work. And the refusal to even try
to improve your skill set, just proves what I said.
You're hack. And apparently quite proud of it.

tabb...@gmail.com

unread,
Nov 23, 2019, 4:42:51 AM11/23/19
to
On Saturday, 23 November 2019 02:11:38 UTC, Fox's Mercantile wrote:
> On 11/22/19 7:40 PM, Cursitor Doom wrote:

> > You can call me a hack as well if you like;
>
> I did.
>
> > I couldn't give a shit TBH.
>
> Actually, that's not true. If you honestly didn't
> give a shit, you wouldn't have wasted the time to
> defend yourself.

he didn't 'defend himself' he explained his position

> > I'm not very practical.
> This too is obvious.
>
> > But do I care? Nope! Because the case goes back on
> > and no one can see it anyway.
>
> No, of course you don't care. That's because you have
> zero pride in your work. And the refusal to even try
> to improve your skill set,

I've read enough of CD's posts to know neither of those is true.
People like you are 100% sure they know what's what even when they don't have the relevant facts. Same old.

Fox's Mercantile

unread,
Nov 23, 2019, 9:28:05 AM11/23/19
to
On 11/23/19 3:42 AM, tabb...@gmail.com wrote:
> he didn't 'defend himself' he explained his position

“When I use a word,” Humpty Dumpty said, in rather a
scornful tone, “it means just what I choose it to mean—
neither more nor less.” “The question is,” said Alice,
“whether you can make words mean so many different things.”
“The question is,” said Humpty Dumpty, “which is to be
master—that's all.”
> I've read enough of CD's posts to know neither of those
> is true. People like you are 100% sure they know what's
> what even when they don't have the relevant facts. Same
> old.

You have a reading comprehension problem.
Coupled with an obsession of always being right.
Especially when you aren't.

Jeff Liebermann

unread,
Nov 23, 2019, 11:45:05 AM11/23/19
to
On Sat, 23 Nov 2019 01:37:35 -0000 (UTC), Cursitor Doom
<cu...@notformail.com> wrote:

>On Fri, 22 Nov 2019 07:54:53 -0800, Jeff Liebermann wrote:
>
>> 1. Are you sure that it was the HP VNA that blew a capacitor or
>> something? When you removed the case, was it lit up?

>Thank you, Jeffrey. Not sure if you were able to read the thread right
>through, but it's been established that the blown cap was an X2 rated one
>fitted right across the incoming mains power line. It took a while to
>confirm this was the actual culprit as it was well buried under a load of
>spaghetti. When I finally got it out I was able to see it had literally
>exploded which accounts for the report I heard from 30' away.
>That cap has now been replaced and the device appears to be working fine
>again, although after 10 years of storage there's no doubt some re-
>aligning and whatnot to be done.

62 articles and growing. I got lazy and just skimmed the articles
posted by those who had a history of successful troubleshooting. I
didn't see anything that looked like success, so I posted my
suggestions on the assumption that the obvious culprits and usual
suspects had been eliminated. Anyway, congrats on fixing the problem.

Cursitor Doom

unread,
Nov 23, 2019, 7:02:36 PM11/23/19
to
On Sat, 23 Nov 2019 08:27:56 -0600, Fox's Mercantile wrote:

> “When I use a word,” Humpty Dumpty said, in rather a scornful tone, “it
> means just what I choose it to mean— neither more nor less.” “The
> question is,” said Alice, “whether you can make words mean so many
> different things.”
> “The question is,” said Humpty Dumpty, “which is to be master—that's
> all.”

I think I can see your problem now: you're a MORON.

Fox's Mercantile

unread,
Nov 23, 2019, 7:54:36 PM11/23/19
to
On 11/23/19 6:02 PM, Cursitor Doom wrote:
> I think I can see your problem now: you're a MORON.

Do you honestly believe I give a flying fuck what you think?

Cursitor Doom

unread,
Nov 24, 2019, 5:08:19 AM11/24/19
to
On Sat, 23 Nov 2019 18:54:28 -0600, Fox's Mercantile wrote:

> On 11/23/19 6:02 PM, Cursitor Doom wrote:
>> I think I can see your problem now: you're a MORON.
>
> Do you honestly believe I give a flying fuck what you think?

Just pointing it out for the benefit of others here who may not yet be
fully familiar with your profane outpourings of ill-informed garbage and
propensity to discharge same.

Fox's Mercantile

unread,
Nov 24, 2019, 8:11:22 AM11/24/19
to
On 11/24/19 4:08 AM, Cursitor Doom wrote:
> On Sat, 23 Nov 2019 18:54:28 -0600, Fox's Mercantile wrote:
>
>> On 11/23/19 6:02 PM, Cursitor Doom wrote:
>>> I think I can see your problem now: you're a MORON.
>>
>> Do you honestly believe I give a flying fuck what you think?
>
> Just pointing it out for the benefit of others here who may not yet be
> fully familiar with your profane outpourings of ill-informed garbage and
> propensity to discharge same.

That's precious.
I pointed out that you're a hack.
I pointed out the Tabby is hack.
You two have been having a love fest trying to justify yourselves.

Get a room.

Cursitor Doom

unread,
Nov 24, 2019, 9:20:41 AM11/24/19
to
On Sun, 24 Nov 2019 07:11:14 -0600, Fox's Mercantile wrote:

> That's precious.
> I pointed out that you're a hack.

You're a *MORON* and a DUMBASS. Did you not see the picture I posted of
the network analyser I freely admitted to butchering earlier in the
thread?

No Sherlock you, but blind as well as rude and ignorant, clearly.

Fox's Mercantile

unread,
Nov 24, 2019, 11:23:59 AM11/24/19
to
On 11/24/19 8:20 AM, Cursitor Doom wrote:
> On Sun, 24 Nov 2019 07:11:14 -0600, Fox's Mercantile wrote:
>
>> That's precious.
>> I pointed out that you're a hack.
>
> You're a *MORON* and a DUMBASS. Did you not see the picture I posted of
> the network analyser I freely admitted to butchering earlier in the
> thread?
>
> No Sherlock you, but blind as well as rude and ignorant, clearly.

Yes I did, that's why I said you're hack.

Cursitor Doom

unread,
Nov 24, 2019, 11:50:45 AM11/24/19
to
On Sun, 24 Nov 2019 10:23:52 -0600, Fox's Mercantile wrote:

> Yes I did, that's why I said you're hack.

No, specifically you said and I quote: "I pointed out that you're a hack"
which implies you have some sort of superior cognitive ability which the
regulars here don't possess. Like as if everyone else needs an obnoxious
*MORON* like you to spoon feed them the obvious!

Fox's Mercantile

unread,
Nov 24, 2019, 3:25:02 PM11/24/19
to
On 11/24/19 10:50 AM, Cursitor Doom wrote:
> On Sun, 24 Nov 2019 10:23:52 -0600, Fox's Mercantile wrote:
>
>> Yes I did, that's why I said you're hack.
>
> No, specifically you said and I quote: "I pointed out that you're a hack"
> which implies you have some sort of superior cognitive ability which the
> regulars here don't possess. Like as if everyone else needs an obnoxious
> *MORON* like you to spoon feed them the obvious!

And there you have it...
You're a hack. You just said so yourself.

tabb...@gmail.com

unread,
Nov 25, 2019, 1:08:39 AM11/25/19
to
On Sunday, 24 November 2019 13:11:22 UTC, Fox's Mercantile wrote:
> On 11/24/19 4:08 AM, Cursitor Doom wrote:
> > On Sat, 23 Nov 2019 18:54:28 -0600, Fox's Mercantile wrote:
> >
> >> On 11/23/19 6:02 PM, Cursitor Doom wrote:
> >>> I think I can see your problem now: you're a MORON.
> >>
> >> Do you honestly believe I give a flying fuck what you think?
> >
> > Just pointing it out for the benefit of others here who may not yet be
> > fully familiar with your profane outpourings of ill-informed garbage and
> > propensity to discharge same.
>
> That's precious.
> I pointed out that you're a hack.
> I pointed out the Tabby is hack.
> You two have been having a love fest trying to justify yourselves.
>
> Get a room.

yet another example of your dishonesty in attempting to convince people of something that has no ground in reality. You have become not worth reading. Bye.


NT

tabb...@gmail.com

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Nov 25, 2019, 1:09:54 AM11/25/19
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On Sunday, 24 November 2019 00:02:36 UTC, Cursitor Doom wrote:
> On Sat, 23 Nov 2019 08:27:56 -0600, Fox's Mercantile wrote:
>
> > “When I use a word,” Humpty Dumpty said, in rather a scornful tone, “it
> > means just what I choose it to mean— neither more nor less.” “The
> > question is,” said Alice, “whether you can make words mean so many
> > different things.”
> > “The question is,” said Humpty Dumpty, “which is to be master—that's
> > all.”
>
> I think I can see your problem now: you're a MORON.

he's become slowman mark 2, a fool with a problem.

Fox's Mercantile

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Nov 25, 2019, 3:48:19 AM11/25/19
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Speaking of slow.
I said he was a hack.
He has finally admitted to being a hack.
I said you were a hack.
I stand by my observation.

Ralph Mowery

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Nov 25, 2019, 2:09:42 PM11/25/19
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In article <JrednUxVUfnRCEbA...@giganews.com>,
jda...@att.net says...
>
> Speaking of slow.
> I said he was a hack.
> He has finally admitted to being a hack.
> I said you were a hack.
> I stand by my observation.
>
>
>

Sometimes it takes a hack to get the job done at a reasonable cost.

Like a car company wanted lots of money to replace a freeze plug on a
car engine. Due to where it was placed , they said the motor needed to
be pulled.

A local hack said he could do it for almost nothing. Pulled the carpet
back inside the car. Took a hole saw on a drill and cut a hole.
Replaced the plug , pop rivited a beer can cutout over the hole and
replaced the carpet.


peterw...@gmail.com

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Nov 25, 2019, 3:16:38 PM11/25/19
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Care to speculate on the horrific consequences of that particular "hack"? And I doubt if those consequences are specific to the US.

Peter Wieck
Melrose Park, PA

Fox's Mercantile

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Nov 25, 2019, 3:22:17 PM11/25/19
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On 11/25/19 1:09 PM, Ralph Mowery wrote:
> Sometimes it takes a hack to get the job done at a reasonable cost.
>
> Like a car company wanted lots of money to replace a freeze plug on a
> car engine. Due to where it was placed , they said the motor needed to
> be pulled.
>
> A local hack said he could do it for almost nothing. Pulled the carpet
> back inside the car. Took a hole saw on a drill and cut a hole.
> Replaced the plug , pop rivited a beer can cutout over the hole and
> replaced the carpet.

That's a clever repair. I did the same thing on a '68 Dodge station
wagon. The freeze plug on the rear of the cylinder heads.
Cut a hole, or pull the intake and the heads. Obvious choice.

WHEN you work on your own vehicle. You have next to zero funds and
you need to drive it into work the next day.

Had I had the time, I would have pulled the engine and replaced all
the freeze plugs at the same time instead of one at a time.

I had the time over the weekend, and that's exactly what I did.
including pulling the flywheel and getting the two behind it.

peterw...@gmail.com

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Nov 25, 2019, 3:30:37 PM11/25/19
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Cut a hole, or pull the intake and the heads. Obvious choice.

Care to speculate, as I asked Ralph, on the consequences?

Fox's Mercantile

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Nov 25, 2019, 4:05:42 PM11/25/19
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On 11/25/19 2:30 PM, pf...@aol.com wrote:
> Cut a hole, or pull the intake and the heads. Obvious choice.
>
> Care to speculate, as I asked Ralph, on the consequences?

As to the operation of the cooling system? No difference of
doing it right. The plug was installed correctly using an
installation tool.
To the vehicle itself? A Campbell's soup can lid pop riveted
to the firewall over the hole I cut. Complete with some
sealant to properly seal the firewall.

However, I might add, that the following weekend, I pulled
the engine out and replaced the rest of the freeze plugs.
Because I didn't want any more trouble with them.

peterw...@gmail.com

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Nov 25, 2019, 6:03:17 PM11/25/19
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Nope. Care to try again?

Al

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Nov 25, 2019, 7:08:13 PM11/25/19
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On Mon, 25 Nov 2019 12:16:34 -0800, pf...@aol.com wrote:

> Care to speculate on the horrific consequences of that particular
> "hack"?

Yeah, I should imagine the possibility of a slight draft in the area of
the footwell that side. Just maybe... But that's all.

Ralph Mowery

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Nov 25, 2019, 7:58:20 PM11/25/19
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In article <qrhqda$roo$3...@dont-email.me>, iqbal...@noreply.com says...
> Care to speculate on the horrific consequences of that particular
> > "hack"?
>
> Yeah, I should imagine the possibility of a slight draft in the area of
> the footwell that side. Just maybe... But that's all.
>
>

No draft, covered by the cut up beer can and carpet.

I doubt a 3 inch in diameter how would cause any real problem. It would
have cost more than the car was worth anyway if the motor had to be
pulled.



Mike Coon

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Nov 26, 2019, 4:37:35 AM11/26/19
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In article <MPG.384642a55...@news.east.earthlink.net>,
rmower...@earthlink.net says...
When I was a student I shared rides in a car with a hole in the floor on
the passenger side. The trick was to keep your foot on the hole to avoid
when going through any puddle getting a jet of water up your trouser
leg.

We probably could not afford a pop-riveter and sealant, and the beer may
have come in bottles. Wet carpets are no fun, either...

Mike.

peterw...@gmail.com

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Nov 26, 2019, 7:01:26 AM11/26/19
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OK. To attempt to get you all to think "outside the box".

Question: Why do we stop at STOP signs, even when there is no one else (visible) around?

You park your car on a hill. You neglect to turn your wheels to the curb. Some kid sees change in your cup-holder and breaks into the car, meanwhile releasing the parking brake. The car rolls down the hill and hurts someone. Who is responsible?

Now, consider that hole in that firewall. Please try to think it through.

John-Del

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Nov 26, 2019, 7:53:27 AM11/26/19
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You're going to hate this story Peter: I had an old Explorer that had a bad fuel pump. This truck was originally sold near the shoreline and and had suffered almost 20 years in the rust belt. There was no chance of getting the fuel tank down without fighting through rusted hardware and other issues, so I got out my nibbler and opened an access hole under the back seat right over the fuel pump flange. 90 min in an out.

peterw...@gmail.com

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Nov 26, 2019, 7:59:58 AM11/26/19
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Which is not the firewall. And, there are actual after-market hatches for that application. Which are not made from aluminum beer-cans and aluminum pop-rivets.

https://www.summitracing.com/parts/tnk-ad-66?seid=srese1&gclid=Cj0KCQiAt_PuBRDcARIsAMNlBdoNrWes9c1ZaHtW5jN_Qigc5WOsWbm7rhtW3ItFjgIdTLDofkTwwZQaAvnoEALw_wcB
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