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Westwind Trantor Hard Disk for Osborne Computer
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John Crane
May 18, 2021, 7:49:15 AM5/18/21
to
Can anyone point me to documentation or schematics for this?
I have one in pristine condition, until last month when a capacitor blew...
Turns out these use the problematic Astec power supplies identical to
the ones used in the Osborne 01. There is a 0.1uF 250V polymer cap that
tends to blow. In fact, I've had 2 Osborne 01 machines that blew while
in service - smoke and all. I replaced the cap and now they work perfectly.
The Westwind, on the other hand, will not recognize the hard disk.
However the built-in ramdisk does work.
My fear is that when the cap blew, a voltage transient may have taken
out one or more of the large Shugart VLSI chips on the disk controller
board. These chips may be difficult to source these days.
-John
I have one in pristine condition, until last month when a capacitor blew...
Turns out these use the problematic Astec power supplies identical to
the ones used in the Osborne 01. There is a 0.1uF 250V polymer cap that
tends to blow. In fact, I've had 2 Osborne 01 machines that blew while
in service - smoke and all. I replaced the cap and now they work perfectly.
The Westwind, on the other hand, will not recognize the hard disk.
However the built-in ramdisk does work.
My fear is that when the cap blew, a voltage transient may have taken
out one or more of the large Shugart VLSI chips on the disk controller
board. These chips may be difficult to source these days.
-John
John Crane
May 18, 2021, 8:07:23 AM5/18/21
to
Can anyone point me to documentation or schematics for this?
I have one in pristine condition, until last month when a capacitor blew...
Turns out these use the problematic Astec power supplies identical to
the ones used in the Osborne 01. There is a 0.1uF 250V polymer cap that
tends to blow. In fact, I've had 2 Osborne 01 machines that blew while
in service. I replaced the cap and now they work perfectly.
I have one in pristine condition, until last month when a capacitor blew...
Turns out these use the problematic Astec power supplies identical to
the ones used in the Osborne 01. There is a 0.1uF 250V polymer cap that
tends to blow. In fact, I've had 2 Osborne 01 machines that blew while
Mike
May 18, 2021, 3:22:07 PM5/18/21
to
In article <168027cfc3d16763$1$2112880$6edd...@news.thundernews.com>,
as part of the incoming filtration?
If so, these infest other stuff, like ICL One Per Desk PSUs, Apple II+
PSUs, SYMBFile 5.25" external harddrive enclosures etc. and they fail
with a crackle, hiss, bang and smoke. In each case, removing the charred
remains stops the smoke and allows the device to work just fine. Replacing
them with appropriate modern caps is possible too, but not essential
to operation.
https://eevblog.com/forum/chat/old-rifa-capacitors-and-a-disaster-story/
>The Westwind, on the other hand, will not recognize the hard disk.
>However the built-in ramdisk does work.
Did the power cut out suddenly when the capacitor went (blown fuse?),
or did you power off in a panic? Could unexpected loss of power have
upset an "old" hard drive (no time to head park?)
--
--------------------------------------+------------------------------------
Mike Brown: mjb[-at-]signal11.org.uk | http://www.signal11.org.uk
John Crane <john_c...@yahoo.com> wrote:
>Turns out these use the problematic Astec power supplies identical to
>the ones used in the Osborne 01. There is a 0.1uF 250V polymer cap that
>tends to blow.
Is it a RIFA Yellow/clear/foil looking thing, wired across Live/Neutral
>Turns out these use the problematic Astec power supplies identical to
>the ones used in the Osborne 01. There is a 0.1uF 250V polymer cap that
>tends to blow.
as part of the incoming filtration?
If so, these infest other stuff, like ICL One Per Desk PSUs, Apple II+
PSUs, SYMBFile 5.25" external harddrive enclosures etc. and they fail
with a crackle, hiss, bang and smoke. In each case, removing the charred
remains stops the smoke and allows the device to work just fine. Replacing
them with appropriate modern caps is possible too, but not essential
to operation.
https://eevblog.com/forum/chat/old-rifa-capacitors-and-a-disaster-story/
>The Westwind, on the other hand, will not recognize the hard disk.
>However the built-in ramdisk does work.
or did you power off in a panic? Could unexpected loss of power have
upset an "old" hard drive (no time to head park?)
--
--------------------------------------+------------------------------------
Mike Brown: mjb[-at-]signal11.org.uk | http://www.signal11.org.uk
John Crane
May 18, 2021, 4:28:00 PM5/18/21
to
On 5/18/21 2:05 PM, Mike wrote:
> In article <168027cfc3d16763$1$2112880$6edd...@news.thundernews.com>,
> John Crane <john_c...@yahoo.com> wrote:
>> Turns out these use the problematic Astec power supplies identical to
>> the ones used in the Osborne 01. There is a 0.1uF 250V polymer cap that
>> tends to blow.
>
> Is it a RIFA Yellow/clear/foil looking thing, wired across Live/Neutral
> as part of the incoming filtration?
Exactly! It is a RIFA.
> In article <168027cfc3d16763$1$2112880$6edd...@news.thundernews.com>,
> John Crane <john_c...@yahoo.com> wrote:
>> Turns out these use the problematic Astec power supplies identical to
>> the ones used in the Osborne 01. There is a 0.1uF 250V polymer cap that
>> tends to blow.
>
> Is it a RIFA Yellow/clear/foil looking thing, wired across Live/Neutral
> as part of the incoming filtration?
>
> If so, these infest other stuff, like ICL One Per Desk PSUs, Apple II+
> PSUs, SYMBFile 5.25" external harddrive enclosures etc. and they fail
> with a crackle, hiss, bang and smoke. In each case, removing the charred
> remains stops the smoke and allows the device to work just fine. Replacing
> them with appropriate modern caps is possible too, but not essential
> to operation.
>
> https://eevblog.com/forum/chat/old-rifa-capacitors-and-a-disaster-story/
>
>> The Westwind, on the other hand, will not recognize the hard disk.
>> However the built-in ramdisk does work.
>
> Did the power cut out suddenly when the capacitor went (blown fuse?),
> or did you power off in a panic? Could unexpected loss of power have
> upset an "old" hard drive (no time to head park?)
>
>
switch. I may have just lost the data and need to reformat. Of course,
I don't see any utilities to do that. So more exploration is needed.
-John
Rayner Lucas
May 18, 2021, 6:34:34 PM5/18/21
to
In article <168043217a113e0f$1$2262039$72dd...@news.thundernews.com>,
john_c...@yahoo.com says...
they *will* blow, with a thick plume of absolutely foul clinging smoke.
They can turn up in just about any mains-powered equipment from the 80s
or 90s, from kitchen appliances to computers to high-end test gear. Any
vintage equipment that plugs into the wall should be considered suspect
until you've checked its power supply to make absolutely certain of the
absence of the damned things.
They should be replaced with equivalent safety capacitors with the same
X or Y rating, never with a normal capacitor. The equipment will also
generally work without them, though without the associated protection
against generating or receiving EMI.
I once dug *eight* RIFA caps out of the power supply in a Tektronix
VM700T test set, only for the back end of the Schaffner branded power
inlet to explode instead. It turns out that Schaffner filtered power
inlets *also* contain RIFA capacitors, concealed inside a metal casing
and some sort of potting material for an especially unwelcome surprise.
I've also seen a near-identical type of cap under the WIMA brand. These
seem much rarer but are just as treacherous.
I expect Mike's right about the drive, I'm only posting because I've
developed a very specific grudge against these things.
R
john_c...@yahoo.com says...
>
> On 5/18/21 2:05 PM, Mike wrote:
> > In article <168027cfc3d16763$1$2112880$6edd...@news.thundernews.com>,
> > John Crane <john_c...@yahoo.com> wrote:
> >> Turns out these use the problematic Astec power supplies identical to
> >> the ones used in the Osborne 01. There is a 0.1uF 250V polymer cap that
> >> tends to blow.
> >
> > Is it a RIFA Yellow/clear/foil looking thing, wired across Live/Neutral
> > as part of the incoming filtration?
>
> Exactly! It is a RIFA.
RIFA filter caps are evil little devices. They don't just tend to blow,
> On 5/18/21 2:05 PM, Mike wrote:
> > In article <168027cfc3d16763$1$2112880$6edd...@news.thundernews.com>,
> > John Crane <john_c...@yahoo.com> wrote:
> >> Turns out these use the problematic Astec power supplies identical to
> >> the ones used in the Osborne 01. There is a 0.1uF 250V polymer cap that
> >> tends to blow.
> >
> > Is it a RIFA Yellow/clear/foil looking thing, wired across Live/Neutral
> > as part of the incoming filtration?
>
> Exactly! It is a RIFA.
they *will* blow, with a thick plume of absolutely foul clinging smoke.
They can turn up in just about any mains-powered equipment from the 80s
or 90s, from kitchen appliances to computers to high-end test gear. Any
vintage equipment that plugs into the wall should be considered suspect
until you've checked its power supply to make absolutely certain of the
absence of the damned things.
They should be replaced with equivalent safety capacitors with the same
X or Y rating, never with a normal capacitor. The equipment will also
generally work without them, though without the associated protection
against generating or receiving EMI.
I once dug *eight* RIFA caps out of the power supply in a Tektronix
VM700T test set, only for the back end of the Schaffner branded power
inlet to explode instead. It turns out that Schaffner filtered power
inlets *also* contain RIFA capacitors, concealed inside a metal casing
and some sort of potting material for an especially unwelcome surprise.
I've also seen a near-identical type of cap under the WIMA brand. These
seem much rarer but are just as treacherous.
I expect Mike's right about the drive, I'm only posting because I've
developed a very specific grudge against these things.
R
Mike
May 19, 2021, 9:22:05 AM5/19/21
to
In article <MPG.3b0e514e...@news.eternal-september.org>,
toast and toffee. Although 100% unwanted when coming out of a piece of
electronic equipment, it's not *that* bad. :)
If the hard drive is an old shoe-box style one (5.25", full height)
that uses stepper motors to trundle the head out over the disk and
back, then they don't tend to like having the head dropped on the
active disk -- any sign of diagnostic LEDs on the drive, as these
can start giving blink-codes to say "Didn't spin up, there's
a head holding me back!" etc.
Rayner Lucas <usenet...@magic-cookie.co.ukNOSPAMPLEASE> wrote:
>with a thick plume of absolutely foul clinging smoke.
I must have got the alternate-flavour ones, somewhere between burnt
>with a thick plume of absolutely foul clinging smoke.
toast and toffee. Although 100% unwanted when coming out of a piece of
electronic equipment, it's not *that* bad. :)
If the hard drive is an old shoe-box style one (5.25", full height)
that uses stepper motors to trundle the head out over the disk and
back, then they don't tend to like having the head dropped on the
active disk -- any sign of diagnostic LEDs on the drive, as these
can start giving blink-codes to say "Didn't spin up, there's
a head holding me back!" etc.
Rayner Lucas
May 19, 2021, 1:36:02 PM5/19/21
to
In article <s833d4$2a5$1...@posie.signal11.org.uk>, m...@signal11.invalid
says...
even with the windows open, but that was from the Schaffner power inlet
incident so the scorched potting gunk may well have contributed that
particular fragrance :-)
R
says...
>
> In article <MPG.3b0e514e...@news.eternal-september.org>,
> Rayner Lucas <usenet...@magic-cookie.co.ukNOSPAMPLEASE> wrote:
>
> >with a thick plume of absolutely foul clinging smoke.
>
> I must have got the alternate-flavour ones, somewhere between burnt
> toast and toffee. Although 100% unwanted when coming out of a piece of
> electronic equipment, it's not *that* bad. :)
I was remembering a lingering phenolic reek that took hours to dissipate
> In article <MPG.3b0e514e...@news.eternal-september.org>,
> Rayner Lucas <usenet...@magic-cookie.co.ukNOSPAMPLEASE> wrote:
>
> >with a thick plume of absolutely foul clinging smoke.
>
> I must have got the alternate-flavour ones, somewhere between burnt
> toast and toffee. Although 100% unwanted when coming out of a piece of
> electronic equipment, it's not *that* bad. :)
even with the windows open, but that was from the Schaffner power inlet
incident so the scorched potting gunk may well have contributed that
particular fragrance :-)
R
Mike Coon
May 19, 2021, 2:48:17 PM5/19/21
to
In article <MPG.3b0f5cd6e...@news.eternal-september.org>,
usenet...@magic-cookie.co.ukNOSPAMPLEASE says...
youth. IIRC like over-cooked school cabbage. I think I might have its
successor in the EHT of my homemade oscilloscope...
usenet...@magic-cookie.co.ukNOSPAMPLEASE says...
>
> I was remembering a lingering phenolic reek that took hours to dissipate
> even with the windows open, but that was from the Schaffner power inlet
> incident so the scorched potting gunk may well have contributed that
> particular fragrance :-)
For an evil smell I can recommend a failed selenium rectifier from my
> I was remembering a lingering phenolic reek that took hours to dissipate
> even with the windows open, but that was from the Schaffner power inlet
> incident so the scorched potting gunk may well have contributed that
> particular fragrance :-)
youth. IIRC like over-cooked school cabbage. I think I might have its
successor in the EHT of my homemade oscilloscope...
John Robertson
May 19, 2021, 3:19:35 PM5/19/21
to
On 2021/05/19 6:21 a.m., Mike wrote:
> In article <MPG.3b0e514e...@news.eternal-september.org>,
> Rayner Lucas <usenet...@magic-cookie.co.ukNOSPAMPLEASE> wrote:
>
>> with a thick plume of absolutely foul clinging smoke.
>
> I must have got the alternate-flavour ones, somewhere between burnt
> toast and toffee. Although 100% unwanted when coming out of a piece of
> electronic equipment, it's not *that* bad. :)
>
> If the hard drive is an old shoe-box style one (5.25", full height)
> that uses stepper motors to trundle the head out over the disk and
> back, then they don't tend to like having the head dropped on the
> active disk -- any sign of diagnostic LEDs on the drive, as these
> can start giving blink-codes to say "Didn't spin up, there's
> a head holding me back!" etc.
>
to pick up the drive and hold it in my hand, then quickly rotate my
wrist in the direction of spin to free up the heads. Then back up the
disk right away!
John :-#)#
T i m
May 19, 2021, 4:24:04 PM5/19/21
to
On Wed, 19 May 2021 12:19:25 -0700, John Robertson <sp...@flippers.com>
wrote:
<snip>
>Might need a "Shake & Bake" operation to get it spinning again...I used
>to pick up the drive and hold it in my hand, then quickly rotate my
>wrist in the direction of spin to free up the heads. Then back up the
>disk right away!
>
I had to do similar with a genuine IBM PC that I'd added a FH (5MB)
ST506 interfaced HDD to that wouldn't always spin up from power-on (I
used it to run the Co BBS (TBBS) and it was typically on 27/7).
I would hit the power switch then sharply twist the whole PC around
about 45 Deg and back (as you say, on the same plane as the platters)
and it always span up. ;-)
Cheers, T i m
wrote:
<snip>
>Might need a "Shake & Bake" operation to get it spinning again...I used
>to pick up the drive and hold it in my hand, then quickly rotate my
>wrist in the direction of spin to free up the heads. Then back up the
>disk right away!
>
ST506 interfaced HDD to that wouldn't always spin up from power-on (I
used it to run the Co BBS (TBBS) and it was typically on 27/7).
I would hit the power switch then sharply twist the whole PC around
about 45 Deg and back (as you say, on the same plane as the platters)
and it always span up. ;-)
Cheers, T i m
John Crane
May 19, 2021, 10:08:36 PM5/19/21
to
Not too bad actually....
-John
John Crane
May 19, 2021, 10:09:40 PM5/19/21
to
-John
Ralph Phillips
May 20, 2021, 6:41:46 PM5/20/21
to
On 5/19/2021 3:24 PM, T i m wrote:
> On Wed, 19 May 2021 12:19:25 -0700, John Robertson <sp...@flippers.com>
> wrote:
> (I
> used it to run the Co BBS (TBBS) and it was typically on 27/7).
Another TBBS alumni!
> On Wed, 19 May 2021 12:19:25 -0700, John Robertson <sp...@flippers.com>
> wrote:
> (I
> used it to run the Co BBS (TBBS) and it was typically on 27/7).
I ran The Golddust Plantation back when.
RwP
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