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Re: Why 6.3 volts?

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Phil Allison

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Dec 10, 2011, 7:45:36 PM12/10/11
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<j...@myplace.com>
>
> The old tube stuff always had 6.3 volts on the filaments (except those
> with other voltages).

** Like 1.25V and 12.6V.


> I always wondered why they used the ".3". Why
> not just an even 6 volts, or 6 and a half? Just curious if there was
> actually some real reason for the .3 volts?


** All three voltages ( and many more) relate to the use of cells or
batteries being used to power the filamants.

1.25V is in the middle of the discharge voltage range for a nominal 1.5 V
dry cell and spot on for a NiFe cell.

Similarly, 6.3V is in the middle of the discharge voltage range for a 3 cell
lead-acid battery.



... Phil



lang...@fonz.dk

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Dec 10, 2011, 7:44:53 PM12/10/11
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On 11 Dec., 01:30, j...@myplace.com wrote:
> The old tube stuff always had 6.3 volts on the filaments (except those
> with other voltages).  I always wondered why they used the ".3".  Why
> not just an even 6 volts, or 6 and a half?  Just curious if there was
> actually some real reason for the .3 volts?

the voltage on a fully charged 6V lead acid battery?

-Lasse

Adrian Jansen

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Dec 10, 2011, 7:47:32 PM12/10/11
to

On 11/12/2011 10:30 AM, j...@myplace.com wrote:
> The old tube stuff always had 6.3 volts on the filaments (except those
> with other voltages). I always wondered why they used the ".3". Why
> not just an even 6 volts, or 6 and a half? Just curious if there was
> actually some real reason for the .3 volts?
>

I would guess 3 lead-acid cells was a reason. Nominal 6 volt batteries
were very common back in the 1920s-40s, when this stuff was orginally
developed.

When indirect heated cathodes were developed, it made sense to use AC,
but at the same voltage as the original DC supplies.

Interestingly 5 volts was also very common for direct heated things like
rectifiers. But a bit rougher than the 5 volts used in the digital world.

--
Regards,

Adrian Jansen adrianjansen at internode dot on dot net
Note reply address is invalid, convert address above to machine form.

Phil Allison

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Dec 10, 2011, 7:57:54 PM12/10/11
to

"Adrian Jansen"


> Interestingly 5 volts was also very common for direct heated things like
> rectifiers.


** Be a bit perverse to use a battery to power the heater in a rectifier
tube.



... Phil


John Larkin

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Dec 10, 2011, 9:57:16 PM12/10/11
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On Sun, 11 Dec 2011 10:47:32 +1000, Adrian Jansen <adr...@qq.vv.net>
wrote:

>
>On 11/12/2011 10:30 AM, j...@myplace.com wrote:
>> The old tube stuff always had 6.3 volts on the filaments (except those
>> with other voltages). I always wondered why they used the ".3". Why
>> not just an even 6 volts, or 6 and a half? Just curious if there was
>> actually some real reason for the .3 volts?
>>
>
>I would guess 3 lead-acid cells was a reason. Nominal 6 volt batteries
>were very common back in the 1920s-40s, when this stuff was orginally
>developed.
>
>When indirect heated cathodes were developed, it made sense to use AC,
>but at the same voltage as the original DC supplies.
>
>Interestingly 5 volts was also very common for direct heated things like
>rectifiers. But a bit rougher than the 5 volts used in the digital world.

The first digital ICs were RTL, and the common supply voltage was 3.6
I think. Horrible little things.

John

VWWall

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Dec 11, 2011, 12:25:52 AM12/11/11
to
And almost every PC has a 3.3V buss.

--
Virg Wall, P.E.

John Larkin

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Dec 11, 2011, 12:55:08 AM12/11/11
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On Sat, 10 Dec 2011 21:25:52 -0800, VWWall <vw...@large.invalid>
wrote:
Things are creeping down. The core voltage on the Altera FPGAs we're
using is 0.9. We're running a lot of the i/o banks at 2.5.

John

Olaf Kaluza

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Dec 11, 2011, 1:19:21 AM12/11/11
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Phil Allison <phi...@tpg.com.au> wrote:

>** Be a bit perverse to use a battery to power the heater in a rectifier
>tube.

Of course! It remembers me to a thingy that use battery power, need
charge everyday, only to power a huge minicontroller to run a java
interpreter in case you like to view a video when you are on your
every day-way or collect data of your life to bothers you with
battery powered comercials.

But fortunatly people are smarter than there phones? :-D

Olaf

Message has been deleted

Jan Panteltje

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Dec 11, 2011, 6:19:42 AM12/11/11
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On a sunny day (Sun, 11 Dec 2011 11:57:54 +1100) it happened "Phil Allison"
<phi...@tpg.com.au> wrote in <9kidgn...@mid.individual.net>:
Well I actually did that in my first 10 kV setup.
Not enough isolation in the transformer.

upsid...@downunder.com

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Dec 11, 2011, 7:18:47 AM12/11/11
to
On Sun, 11 Dec 2011 10:47:32 +1000, Adrian Jansen <adr...@qq.vv.net>
wrote:

>Interestingly 5 volts was also very common for direct heated things like
>rectifiers. But a bit rougher than the 5 volts used in the digital world.

Since the rectifier cathode sits at the anode voltage line potential
at a few hundred volts, a separate secondary winding was required to
feed the rectifier filament, thus it was irrelevant if 4 V (AZnn) or 5
V (GZnn) was used.

mpm

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Dec 11, 2011, 8:16:26 AM12/11/11
to
On Dec 10, 7:30 pm, j...@myplace.com wrote:
> The old tube stuff always had 6.3 volts on the filaments (except those
> with other voltages).  I always wondered why they used the ".3".  Why
> not just an even 6 volts, or 6 and a half?  Just curious if there was
> actually some real reason for the .3 volts?

When you figure this out, could you then let us know why they charge
the $0.009 cents on each gallon of gasoline (in the US)?

As to the 6.3, tubes were just a little before my time.
Other than the seemingly correct answers already provided, having the
".3" lends an arbitrary precision.
If you just said "6", someone might think "5" would be close enough.
Say "6.3", and they're likely to re-think it.

Jamie

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Dec 11, 2011, 9:28:48 AM12/11/11
to
j...@myplace.com wrote:
> On Sun, 11 Dec 2011 10:47:32 +1000, Adrian Jansen <adr...@qq.vv.net>
> wrote:
>
>
>>On 11/12/2011 10:30 AM, j...@myplace.com wrote:
>>
>>>The old tube stuff always had 6.3 volts on the filaments (except those
>>>with other voltages). I always wondered why they used the ".3". Why
>>>not just an even 6 volts, or 6 and a half? Just curious if there was
>>>actually some real reason for the .3 volts?
>>>
>>
>>I would guess 3 lead-acid cells was a reason. Nominal 6 volt batteries
>>were very common back in the 1920s-40s, when this stuff was orginally
>>developed.
>>
>>When indirect heated cathodes were developed, it made sense to use AC,
>>but at the same voltage as the original DC supplies.
>>
>>Interestingly 5 volts was also very common for direct heated things like
>>rectifiers. But a bit rougher than the 5 volts used in the digital world.
>
>
> A simple answer. Kind of makes me ask "why didn't I think of that" :)
> Yep, 2.1 v per cell, still the same today for lead acid batteries
> except they are all 12v today. Actually 12.6, but I've never heard the
> .6 used for a car battery.
>
> I recall the old carbon zinc flashlight batteries were 1.5 volts, so
> this all makes sense now, except using 4 of them would yield a
> straight 6.0v.
ACtually they are not..

a fresh carbon cell should yield ~ 1.578 volts. which equals ~ 6.3
volts DC.
We used that as a calibration source years ago.

Jamie


k...@att.bizzzzzzzzzzzz

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Dec 11, 2011, 11:25:30 AM12/11/11
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On Sun, 11 Dec 2011 05:16:26 -0800 (PST), mpm <mpmi...@aol.com> wrote:

>On Dec 10, 7:30 pm, j...@myplace.com wrote:
>> The old tube stuff always had 6.3 volts on the filaments (except those
>> with other voltages).  I always wondered why they used the ".3".  Why
>> not just an even 6 volts, or 6 and a half?  Just curious if there was
>> actually some real reason for the .3 volts?
>
>When you figure this out, could you then let us know why they charge
>the $0.009 cents on each gallon of gasoline (in the US)?

They don't. They give you $.001 off. It's called "marketing". It's like
paper $1 bills and the Imperial system; inertia is sometimes tough to
overcome.

Hellequin

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Dec 11, 2011, 12:59:13 PM12/11/11
to
Ding! Perhaps carbon zinc or such for handheld radios, etc. I had one
that used 63 volt batteries. No lead acid though.

Back then, designs had to follow available elements (not that they no
longer do). So designers formed the standards entire industries had to
follow so things would all work properly.

It may have to do with a certain size nichrome wire and the folks
arriving at some ideal voltage to feed some ideal length heater wire,
which the industry then adopted as a standard.

Kind of like Edison's light bulb base. On a 120 volt light bulb, the
filaments are the same length, and the diameter of the wire is reduced to
increase wattage and brightness, but usually means a decrease in
lifespan. Vacuum tubes have to live a long life, but create enough heat
to function. There is a happy point in nichrome wire where lifespan and
brightness and power consumption all cross (or they engineer guy says
"That's a good spot"). At some point the entire group sets a standard an
entire industry follows.

These days, we have "associations" of manufacturers whom all agree to
agree with each other.

Back then, the first one to market with something new could set down
the way it gets done by all their competitors in the future.

Hellequin

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Dec 11, 2011, 1:03:38 PM12/11/11
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On Sun, 11 Dec 2011 11:57:54 +1100, "Phil Allison" <phi...@tpg.com.au>
wrote:
It does sound funny.

Hellequin

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Dec 11, 2011, 1:08:43 PM12/11/11
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On Sat, 10 Dec 2011 21:25:52 -0800, VWWall <vw...@large.invalid> wrote:

TTL used to be 5 Volts (still is), but we have slowly whittled that
down because it is quicker to slew less between a 1 and a 0 and it
consumes less power. They are operating at far lower than 3.3 Volts now.

John Larkin

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Dec 11, 2011, 1:37:18 PM12/11/11
to
On Sun, 11 Dec 2011 05:16:26 -0800 (PST), mpm <mpmi...@aol.com>
wrote:

>On Dec 10, 7:30 pm, j...@myplace.com wrote:
>> The old tube stuff always had 6.3 volts on the filaments (except those
>> with other voltages).  I always wondered why they used the ".3".  Why
>> not just an even 6 volts, or 6 and a half?  Just curious if there was
>> actually some real reason for the .3 volts?
>
>When you figure this out, could you then let us know why they charge
>the $0.009 cents on each gallon of gasoline (in the US)?

It's actually an anti-rounding down that avoids a tax increment.

John

Message has been deleted

mpm

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Dec 11, 2011, 7:30:54 PM12/11/11
to
On Dec 11, 11:25 am, "k...@att.bizzzzzzzzzzzz"
<k...@att.bizzzzzzzzzzzz> wrote:
> >Say "6.3", and they're likely to re-think it.- Hide quoted text -
>
> - Show quoted text -

Oh - I always assumed that was a tax !!
Like we're not already screwed enough at the pump as it is. :)

Diesel here is selling for $3.999
I mean really, just round it up to $4.
The pumps stop at $99 anyway due (I guess?) to credit/debit card
limitations.



k...@att.bizzzzzzzzzzzz

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Dec 11, 2011, 8:02:39 PM12/11/11
to
On Sun, 11 Dec 2011 16:30:54 -0800 (PST), mpm <mpmi...@aol.com> wrote:

>On Dec 11, 11:25 am, "k...@att.bizzzzzzzzzzzz"
><k...@att.bizzzzzzzzzzzz> wrote:
>> On Sun, 11 Dec 2011 05:16:26 -0800 (PST), mpm <mpmill...@aol.com> wrote:
>> >On Dec 10, 7:30 pm, j...@myplace.com wrote:
>> >> The old tube stuff always had 6.3 volts on the filaments (except those
>> >> with other voltages).  I always wondered why they used the ".3".  Why
>> >> not just an even 6 volts, or 6 and a half?  Just curious if there was
>> >> actually some real reason for the .3 volts?
>>
>> >When you figure this out, could you then let us know why they charge
>> >the $0.009 cents on each gallon of gasoline (in the US)?
>>
>> They don't.  They give you $.001 off.  It's called "marketing". It's like
>> paper $1 bills and the Imperial system; inertia is sometimes tough to
>> overcome.
>>
>>
>>
>> >As to the 6.3, tubes were just a little before my time.
>> >Other than the seemingly correct answers already provided, having the
>> >".3" lends an arbitrary precision.
>> >If you just said "6", someone might think "5" would be close enough.
>> >Say "6.3", and they're likely to re-think it.- Hide quoted text -
>>
>> - Show quoted text -
>
>Oh - I always assumed that was a tax !!
>Like we're not already screwed enough at the pump as it is. :)

Nah, it's like $9.98, instead of $10. It looks like it's less.

>Diesel here is selling for $3.999
>I mean really, just round it up to $4.

Exactly. How many items in the store are $xx.00? It's called "marketing" and
it works. People really do think $9.99 is significantly less than $10.00.

>The pumps stop at $99 anyway due (I guess?) to credit/debit card
>limitations.

Different issue entirely. The pumps around here say the limits are $90 Amex,
and $75 for everyone else. That limit is because they put a "reserve" of that
much on your account and then settle the actual amount some time later
(usually a few hours). If you're long-distance driving you can occasionally
beat them to clear the reserve and the card may be rejected (trying to fill
twice, I suppose). I ran into this problem on my last trip to the People's
Republic of Vermont. Had to use another card.

RST Engineering

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Dec 12, 2011, 5:38:15 PM12/12/11
to
On Sat, 10 Dec 2011 18:57:16 -0800, John Larkin
<jjla...@highNOTlandTHIStechnologyPART.com> wrote:


>The first digital ICs were RTL, and the common supply voltage was 3.6
>I think. Horrible little things.
>
>John


Yeah, but I bought my first airplane with the profit I made from
Fairchild stock. First time I worked with those little buggers (time
code generator) I told myself that this company was really going to go
big. Still have a few of them around as museum pieces.

Jim

RST Engineering

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Dec 12, 2011, 5:44:59 PM12/12/11
to
On Sun, 11 Dec 2011 03:45:38 -0600, j...@myplace.com wrote:


>>I would guess 3 lead-acid cells was a reason. Nominal 6 volt batteries
>>were very common back in the 1920s-40s, when this stuff was orginally
>>developed.

Think about it. When the first tubes with 6 volt filaments were
designed, most automobiles had 6 volt electrical systems. If you
wanted to use the same tubes for car radios as home radios, you used
the same filament voltage.

In the mid-50s automobiles switched to 12 volt systems and
RCA/Sylvania/GE, and the rest went to 12 volt filaments.

The all-American 5 used a 50C5 audio power, 35W4 rectifier, 12BE6
RF-Converter, 12BA6 IF, 12AT6 detector-audio preamp. Add up the
filament voltages for an interesting look at a transformerless line
voltage receiver.

Thanks,

Jim

Hellequin

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Dec 12, 2011, 7:45:03 PM12/12/11
to
On Mon, 12 Dec 2011 14:44:59 -0800, RST Engineering <jwe...@gmail.com>
wrote:

>On Sun, 11 Dec 2011 03:45:38 -0600, j...@myplace.com wrote:
>
>
>>>I would guess 3 lead-acid cells was a reason. Nominal 6 volt batteries
>>>were very common back in the 1920s-40s, when this stuff was orginally
>>>developed.
>
>Think about it. When the first tubes with 6 volt filaments were
>designed, most automobiles had 6 volt electrical systems.

So what. None of them had tubes and car radios were not incorporated
yet.

> If you
>wanted to use the same tubes for car radios as home radios, you used
>the same filament voltage.

It appear that you like to guess at things. You're not very goo at it.

>
>In the mid-50s automobiles switched to 12 volt systems and
>RCA/Sylvania/GE, and the rest went to 12 volt filaments.

Autos went to 12 Volts before the 50s, and tubes are STILL 6.3 volt
filament devices. And any change they made was not because of the auto
industry.

>The all-American 5 used a 50C5 audio power, 35W4 rectifier, 12BE6
>RF-Converter, 12BA6 IF, 12AT6 detector-audio preamp. Add up the
>filament voltages for an interesting look at a transformerless line
>voltage receiver.

They are all 6.3 volt filaments.

Phil Hobbs

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Dec 12, 2011, 9:36:38 PM12/12/11
to
And prudence probably dictated that the voltages be different, to
prevent wiseacres from trying to use the same winding for the rectifier
and signal tube heaters. :)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics

160 North State Road #203
Briarcliff Manor NY 10510
845-480-2058

hobbs at electrooptical dot net
http://electrooptical.net

John G

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Dec 12, 2011, 9:44:00 PM12/12/11
to
Phil Hobbs formulated the question :
> On 12/11/2011 7:18 AM, upsid...@downunder.com wrote:
>> On Sun, 11 Dec 2011 10:47:32 +1000, Adrian Jansen<adr...@qq.vv.net>
>> wrote:
>>
>>> Interestingly 5 volts was also very common for direct heated things like
>>> rectifiers. But a bit rougher than the 5 volts used in the digital world.
>>
>> Since the rectifier cathode sits at the anode voltage line potential
>> at a few hundred volts, a separate secondary winding was required to
>> feed the rectifier filament, thus it was irrelevant if 4 V (AZnn) or 5
>> V (GZnn) was used.
>>
>
> And prudence probably dictated that the voltages be different, to prevent
> wiseacres from trying to use the same winding for the rectifier and signal
> tube heaters. :)
>
> Cheers
>
> Phil Hobbs

Spot on IMHO.

--
John G.


John Larkin

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Dec 12, 2011, 10:49:26 PM12/12/11
to
The round 8-lead black glob-top things?

John

RST Engineering

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Dec 13, 2011, 1:28:19 AM12/13/11
to
Yeppers. As I recall without digging out the data sheets, an AND
gate, a NOR gate, and a JK flipper.

Jim

RST Engineering

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Dec 13, 2011, 1:35:43 AM12/13/11
to
On Mon, 12 Dec 2011 16:45:03 -0800, Hellequin
<Hell...@yourpipesaremypipes.org> wrote:


>>Think about it. When the first tubes with 6 volt filaments were
>>designed, most automobiles had 6 volt electrical systems.
>
> So what. None of them had tubes and car radios were not incorporated
>yet.

I don't know whe the hell you are, but you'd be well advised to take
my class on the history of electronics. Car radios were introduced in
the 1930s.

>
>> If you
>>wanted to use the same tubes for car radios as home radios, you used
>>the same filament voltage.
>
> It appear that you like to guess at things. You're not very goo at it.

I don't "goo" at anything. Get a spell checker.
>
>>
>>In the mid-50s automobiles switched to 12 volt systems and
>>RCA/Sylvania/GE, and the rest went to 12 volt filaments.
>
> Autos went to 12 Volts before the 50s, and tubes are STILL 6.3 volt
>filament devices. And any change they made was not because of the auto
>industry.

I could be wrong. I've been wrong before. But to the best of my
recollection the '53 Ford was the first 12 volt electrical system.


>
>>The all-American 5 used a 50C5 audio power, 35W4 rectifier, 12BE6
>>RF-Converter, 12BA6 IF, 12AT6 detector-audio preamp. Add up the
>>filament voltages for an interesting look at a transformerless line
>>voltage receiver.
>
> They are all 6.3 volt filaments.

I refuse to have a battle of wits with an unarmed person. See ya
later, Dumbo.

Jim

Phil Allison

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Dec 13, 2011, 2:18:46 AM12/13/11
to

"RST Engineering"

> I don't know whe the hell you are, but you'd be well advised to take
> my class on the history of electronics. Car radios were introduced in
> the 1930s.


** By none other than Motorola in fact:

http://en.wikipedia.org/wiki/Car_audio#1930s




... Phil


John Fields

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Dec 13, 2011, 7:05:15 AM12/13/11
to
On Mon, 12 Dec 2011 16:45:03 -0800, Hellequin
<Hell...@yourpipesaremypipes.org> wrote:

>On Mon, 12 Dec 2011 14:44:59 -0800, RST Engineering <jwe...@gmail.com>
>wrote:

>>The all-American 5 used a 50C5 audio power, 35W4 rectifier, 12BE6
>>RF-Converter, 12BA6 IF, 12AT6 detector-audio preamp. Add up the
>>filament voltages for an interesting look at a transformerless line
>>voltage receiver.
>
> They are all 6.3 volt filaments.

---
It could be argued that the 12V filaments are really two 6V filaments
in series with their ends and their junction brought out of the tube,
but the 50C5 sports a 50V filament and the 35W4 a 35V one.


--
JF

Hellequin

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Dec 13, 2011, 8:20:55 AM12/13/11
to
On Mon, 12 Dec 2011 22:35:43 -0800, RST Engineering <jwe...@gmail.com>
wrote:

>On Mon, 12 Dec 2011 16:45:03 -0800, Hellequin
><Hell...@yourpipesaremypipes.org> wrote:
>
>
>>>Think about it. When the first tubes with 6 volt filaments were
>>>designed, most automobiles had 6 volt electrical systems.
>>
>> So what. None of them had tubes and car radios were not incorporated
>>yet.
>
>I don't know whe the hell you are, but you'd be well advised to take
>my class on the history of electronics.


Sorry, but I won't be taking any class of yours.

Tubes had 2 volt filaments. Batteries were the reason. The 6.3 volt
filaments were because of batteries as well, but it had nothing to do
with the automotive industry.

> Car radios were introduced in
>the 1930s.

In VERY FEW cars, as it was the onset of the Great Depression.

>>> If you
>>>wanted to use the same tubes for car radios as home radios, you used
>>>the same filament voltage.
>>
>> It appear that you like to guess at things. You're not very goo at it.
>
>I don't "goo" at anything. Get a spell checker.


You're being about as immature as usual, asshole.

>>>In the mid-50s automobiles switched to 12 volt systems and
>>>RCA/Sylvania/GE, and the rest went to 12 volt filaments.
>>
>> Autos went to 12 Volts before the 50s, and tubes are STILL 6.3 volt
>>filament devices. And any change they made was not because of the auto
>>industry.
>
>I could be wrong.

Pretty likely, especially considering your attitude and apparent
thinking that you are some fucking doctor of history at it, yet admit
here that you do not actually know a goddamned thing.

> I've been wrong before.

I would never have guessed.

> But to the best of my
>recollection the '53 Ford was the first 12 volt electrical system.

Yet no citations. And you claim to have a "course"? HA!

Hellequin

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Dec 13, 2011, 8:23:21 AM12/13/11
to
On Tue, 13 Dec 2011 18:18:46 +1100, "Phil Allison" <phi...@tpg.com.au>
wrote:

>
Yeah. There must have been a whole 300 of them installed throughout
the entire depression decade.

SMS

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Dec 13, 2011, 10:10:07 AM12/13/11
to
On 12/11/2011 5:16 AM, mpm wrote:
> On Dec 10, 7:30 pm, j...@myplace.com wrote:
>> The old tube stuff always had 6.3 volts on the filaments (except those
>> with other voltages). I always wondered why they used the ".3". Why
>> not just an even 6 volts, or 6 and a half? Just curious if there was
>> actually some real reason for the .3 volts?
>
> When you figure this out, could you then let us know why they charge
> the $0.009 cents on each gallon of gasoline (in the US)?

That's a legacy from back when gasoline prices were in cents and tenths
of cents. The tenths were not always set to nine, and a difference of
tenths of a cent represented a substantial percentage of the per gallon
price. It's rather silly now.

I recall when the oil companies first began jacking up the price of
gasoline and some pumps could not go over 99.9. Some stations were
setting their pumps to half the per gallon price (xx.4) and then
doubling the pump total to yy.8.

John Larkin

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Dec 13, 2011, 10:11:55 AM12/13/11
to
On Mon, 12 Dec 2011 22:28:19 -0800, RST Engineering
<jwe...@gmail.com> wrote:

>On Mon, 12 Dec 2011 19:49:26 -0800, John Larkin
><jjla...@highNOTlandTHIStechnologyPART.com> wrote:
>
>>On Mon, 12 Dec 2011 14:38:15 -0800, RST Engineering
>><jwe...@gmail.com> wrote:
>
>>The round 8-lead black glob-top things?
>>
>>John
>
>Yeppers. As I recall without digging out the data sheets, an AND
>gate, a NOR gate, and a JK flipper.
>
>Jim

Those were so awful that even DTL was an improvement.

John

John Larkin

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Dec 13, 2011, 10:14:29 AM12/13/11
to
On Mon, 12 Dec 2011 22:35:43 -0800, RST Engineering
<jwe...@gmail.com> wrote:

>On Mon, 12 Dec 2011 16:45:03 -0800, Hellequin
><Hell...@yourpipesaremypipes.org> wrote:
>
>
>>>Think about it. When the first tubes with 6 volt filaments were
>>>designed, most automobiles had 6 volt electrical systems.
>>
>> So what. None of them had tubes and car radios were not incorporated
>>yet.
>
>I don't know whe the hell you are,

Sounds like another incarnation of AlwaysWrong.

He is. Really. Always Wrong.

John


John Larkin

unread,
Dec 13, 2011, 10:15:47 AM12/13/11
to
On Tue, 13 Dec 2011 05:20:55 -0800, Hellequin
<Hell...@yourpipesaremypipes.org> wrote:

>On Mon, 12 Dec 2011 22:35:43 -0800, RST Engineering <jwe...@gmail.com>
>wrote:
>
>>On Mon, 12 Dec 2011 16:45:03 -0800, Hellequin
>><Hell...@yourpipesaremypipes.org> wrote:
>>
>>
>>>>Think about it. When the first tubes with 6 volt filaments were
>>>>designed, most automobiles had 6 volt electrical systems.
>>>
>>> So what. None of them had tubes and car radios were not incorporated
>>>yet.
>>
>>I don't know whe the hell you are, but you'd be well advised to take
>>my class on the history of electronics.
>
>
> Sorry, but I won't be taking any class of yours.
>
> Tubes had 2 volt filaments. Batteries were the reason. The 6.3 volt
>filaments were because of batteries as well, but it had nothing to do
>with the automotive industry.
>
>> Car radios were introduced in
>>the 1930s.
>
> In VERY FEW cars, as it was the onset of the Great Depression.

Police radios. Remember "Police Radio Car"?

John

John Larkin

unread,
Dec 13, 2011, 11:14:11 AM12/13/11
to
On Tue, 13 Dec 2011 07:10:07 -0800, SMS <scharf...@geemail.com>
wrote:
Prices in the US very often end in "9". That avoids an increment of
sales tax.

John

Spehro Pefhany

unread,
Dec 13, 2011, 11:56:21 AM12/13/11
to
How do you figure that?

Sales tax in the NY state area where I often shop is 8.25%, so the
nine doesn't generally help.

http://en.wikipedia.org/wiki/Psychological_pricing

I've seen a trend in restaurants in recent years to mark things in
even dollars without the $ sign. Eg. 'Insalata Caprese 10'.


VWWall

unread,
Dec 13, 2011, 12:12:03 PM12/13/11
to
John Fields wrote:
> On Mon, 12 Dec 2011 16:45:03 -0800, Hellequin
> <Hell...@yourpipesaremypipes.org> wrote:
>
>> On Mon, 12 Dec 2011 14:44:59 -0800, RST Engineering <jwe...@gmail.com>
>> wrote:
>
>>> The all-American 5 used a 50C5 audio power, 35W4 rectifier, 12BE6
>>> RF-Converter, 12BA6 IF, 12AT6 detector-audio preamp. Add up the
>>> filament voltages for an interesting look at a transformerless line
>>> voltage receiver.

>> They are all 6.3 volt filaments.
>
Said AlwaysWrong in another of his endless nyms!

> It could be argued that the 12V filaments are really two 6V filaments
> in series with their ends and their junction brought out of the tube,
> but the 50C5 sports a 50V filament and the 35W4 a 35V one.

Just to be correct, none of these had "filaments", they were actually
"heaters" which did not emit electrons, but heated the cathode sleeve
around them. This was the element that produced the electron stream
that made the tubes work.

Almost the only tubes still using an emitting filament are the
rectifiers, and they are almost extinct due to solid state replacements.

Emitting filaments are not completely extinct. There are millions of
magnetrons in microwave ovens that still use them. This allows for
power control by cycling the total power to the tube.

--
Virg Wall

ehsjr

unread,
Dec 13, 2011, 12:26:21 PM12/13/11
to
Yup. As I recall, the first digits always* indicated the filament
voltage.

* I think there were some exceptions, like tubes with the single
digit 1 before the letter. The 1 meant ~1.5 volts, not 1 volt,
if my very fuzzy memory is correct.

Ed

John Larkin

unread,
Dec 13, 2011, 12:44:30 PM12/13/11
to
On Tue, 13 Dec 2011 09:12:03 -0800, VWWall <vw...@large.invalid>
wrote:
Some big transmitting tubes still use filamants. Some of them run at
hundreds, or thousands, of amps. Somebody posted a link a while back
to a tube that uses something like 25KW of filament power.

John


VWWall

unread,
Dec 13, 2011, 1:52:32 PM12/13/11
to
I just flipped open the old RCA Tube Handbook and found the 5770 power
triode which, like most high power transmitting tubes, has a true
filament. It runs at 11 AC or DC volts at 285 amperes. Other tubes had
filament voltages ranging from 4.5 to 22 volts.

The main advantage of a heater is that it allows the true cathode to be
set at a voltage, (within reason), differing from that of the heater.
It also allows a selection of the properties of the emitter itself apart
from the pure heating function of the separate heater.

--
Virg Wall

Michael A. Terrell

unread,
Dec 13, 2011, 1:56:51 PM12/13/11
to
Get your facts straight: They were introduced by Galvin. Their car
radio product was called Motorola, and later Galvin changed their name
to Motorola.


--
You can't have a sense of humor, if you have no sense.

Michael A. Terrell

unread,
Dec 13, 2011, 2:01:34 PM12/13/11
to
The 35W4 has two filaments. A 29 V and a 6 V for a total of 35
volts. This was done to let the AA5 family of radios use a #47 or
similar pilot lamp.

Michael A. Terrell

unread,
Dec 13, 2011, 2:04:36 PM12/13/11
to

mpm wrote:
>
> When you figure this out, could you then let us know why they charge
> the $0.009 cents on each gallon of gasoline (in the US)?


It was a woman's idea in the very early das of retail gasoline
sales. Read the history of the Ethyl corporation for the details. They
made the lead additive for gasoline, as well.

John Fields

unread,
Dec 13, 2011, 2:39:57 PM12/13/11
to
---
Damn fine catch, Michael!

Thanks. :-)

news:7l8m12t34nq1ed...@4ax.com



--
JF

Phil Hobbs

unread,
Dec 13, 2011, 4:29:00 PM12/13/11
to
And of course it reduces the hum produced by minor errors in filament
placement.

Hellequin

unread,
Dec 13, 2011, 8:00:19 PM12/13/11
to
The police were not radio-ing each other in the 30s.

Hellequin

unread,
Dec 13, 2011, 8:03:33 PM12/13/11
to
On Tue, 13 Dec 2011 09:12:03 -0800, VWWall <vw...@large.invalid> wrote:

>Just to be correct, none of these had "filaments", they were actually
>"heaters" which did not emit electrons,

Heater filaments, idiot.

The term was NOT strictly a description of a photon emitting
light bulb component, you dopey fuck. And a light bulb filament is not
for "emitting electrons" either.

They (tube heating elements) were most certainly referred to by both
terms, and both were correct.

So, your "Just to be correct..." ISN'T.

Hellequin

unread,
Dec 13, 2011, 8:06:27 PM12/13/11
to
On Tue, 13 Dec 2011 09:12:03 -0800, VWWall <vw...@large.invalid> wrote:

> but heated the cathode sleeve
>around them. This was the element that produced the electron stream
>that made the tubes work.

No shit, Sherlock.

The filament was never meant to be the emitting element. They were
always meant to heat a nearby electrical element. The only reason one
sees them on a schematic is because they are heated by an electrical
current. They perform no electrical function however. It is purely
mechanical, and those mechanics allow the tube to operate in its
electrical function properly.

tm

unread,
Dec 13, 2011, 8:11:15 PM12/13/11
to

"Hellequin" <Hell...@yourpipesaremypipes.org> wrote in message
news:u7tfe71u0fhfq4n3p...@4ax.com...
Wrong again, always wrong. "radio-ing"? Not only are you always wrong but
you are stupid too.

http://www.baltimorepolice.org/about-us/police-department/history

1933 begins radio dispatch patrol cars. It was one way, HQ to the cars.
Reply was done by call boxes.



Hellequin

unread,
Dec 13, 2011, 8:08:07 PM12/13/11
to
On Tue, 13 Dec 2011 12:26:21 -0500, ehsjr <eh...@nospamverizon.net>
wrote:
The little Raytheon baby finger sized tubes had odd filament voltages.

Hellequin

unread,
Dec 13, 2011, 8:10:23 PM12/13/11
to
He didn't catch it. He lived it.

Spehro Pefhany

unread,
Dec 13, 2011, 8:33:22 PM12/13/11
to
Two-way radios begain in early 1933 in Joisey.. and thence
nationwide:-

http://www.ieeeghn.org/wiki/index.php/Milestones:Two-Way_Police_Radio_Communication,_1933




Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
sp...@interlog.com Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com

Jamie

unread,
Dec 13, 2011, 8:40:08 PM12/13/11
to
If they don't perform no electrical function than where does the
required electron cloud mass come from?



Jamie



Spehro Pefhany

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Dec 13, 2011, 8:37:15 PM12/13/11
to

John Larkin

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Dec 13, 2011, 8:42:32 PM12/13/11
to
On Tue, 13 Dec 2011 17:00:19 -0800, Hellequin
Amazing that you never figured out how to use google!

http://inventors.about.com/od/fstartinventions/a/forensic_4.htm

1928
Detroit police begin using the one-way radio.

1934
Boston Police begin using the two-way radio.


http://www.ci.irvine.ca.us/ipd/divisions/dispatch/911_dispatch.asp

California joined the group in 1929. Police cars in San Francisco,
Berkeley and Pasadena began to equip their vehicles with radio
receivers. Again, these were one-way radios. The first two-way radio
was used in Bayonne, New Jersey in 1933. This connected the Police
Department to nine of their patrol vehicles.


AlwaysWrong!

John



John Larkin

unread,
Dec 13, 2011, 8:44:58 PM12/13/11
to
On Tue, 13 Dec 2011 17:06:27 -0800, Hellequin
<Hell...@yourpipesaremypipes.org> wrote:

>On Tue, 13 Dec 2011 09:12:03 -0800, VWWall <vw...@large.invalid> wrote:
>
>> but heated the cathode sleeve
>>around them. This was the element that produced the electron stream
>>that made the tubes work.
>
> No shit, Sherlock.
>
> The filament was never meant to be the emitting element.

The first tubes used filamants as the electron source. Big
transmitting tunes still do, thoriated tungsten and such.

AlwaysWrong!

John

Hellequin

unread,
Dec 13, 2011, 8:51:58 PM12/13/11
to
The cathode is heated, and it is the cathode that emits, idiot. The
cathode is part of the electrical circuit and function when IT gets hot
enough.

Hellequin

unread,
Dec 13, 2011, 8:52:48 PM12/13/11
to
On Tue, 13 Dec 2011 17:42:32 -0800, John Larkin
<jjla...@highNOTlandTHIStechnologyPART.com> wrote:

> Police cars in San Francisco,
>Berkeley and Pasadena began to equip their vehicles with radio
>receivers. Again, these were one-way radios.

Now look at my remark again, idiot.

John Larkin

unread,
Dec 13, 2011, 8:57:24 PM12/13/11
to
Look at the stuff you snipped, moron.

Two-way in 1933.

AlwaysWrong.

John

Hellequin

unread,
Dec 13, 2011, 9:54:45 PM12/13/11
to
On Tue, 13 Dec 2011 17:57:24 -0800, John Larkin
<jjla...@highNOTlandTHIStechnologyPART.com> wrote:

>On Tue, 13 Dec 2011 17:52:48 -0800, Hellequin
><Hell...@yourpipesaremypipes.org> wrote:
>
>>On Tue, 13 Dec 2011 17:42:32 -0800, John Larkin
>><jjla...@highNOTlandTHIStechnologyPART.com> wrote:
>>
>>> Police cars in San Francisco,
>>>Berkeley and Pasadena began to equip their vehicles with radio
>>>receivers. Again, these were one-way radios.
>>
>> Now look at my remark again, idiot.
>
>Look at the stuff you snipped, moron.
>
>Two-way in 1933.
>
>AlwaysWrong.
>
>John

I said they were not talking to each other. They weren't. Period.
It doesn't have a goddamned thing to do with something snipped, idiot.

They were receive only at first, and that reception was from the
dispatcher only, and even when they went to transceivers, they
communicated with the dispatcher, not each other.

k...@att.bizzzzzzzzzzzz

unread,
Dec 13, 2011, 10:11:18 PM12/13/11
to
On Tue, 13 Dec 2011 07:14:29 -0800, John Larkin
<jjla...@highNOTlandTHIStechnologyPART.com> wrote:

>On Mon, 12 Dec 2011 22:35:43 -0800, RST Engineering
><jwe...@gmail.com> wrote:
>
>>On Mon, 12 Dec 2011 16:45:03 -0800, Hellequin
>><Hell...@yourpipesaremypipes.org> wrote:
>>
>>
>>>>Think about it. When the first tubes with 6 volt filaments were
>>>>designed, most automobiles had 6 volt electrical systems.
>>>
>>> So what. None of them had tubes and car radios were not incorporated
>>>yet.
>>
>>I don't know whe the hell you are,
>
>Sounds like another incarnation of AlwaysWrong.

It is.

>He is. Really. Always Wrong.

He is.

Michael A. Terrell

unread,
Dec 13, 2011, 10:25:10 PM12/13/11
to
I replaced enough of the damned things with open filaments caused by
burnt out pilot lamps. Most manufacturers were too cheap to add the
fixed resistor across the lamp to protect the tube, since the radio
would be long past the warranty when the lamp failed. It was such a
comon failure that some shops put up a small sign over the radio bench
to remind the new techs to always check the pilot lamp before doing any
other work on either type of AA5. The octal version was the 35Z5.


> Thanks. :-)


You're welcome. :)

John Larkin

unread,
Dec 13, 2011, 10:39:41 PM12/13/11
to
On Tue, 13 Dec 2011 18:54:45 -0800, Hellequin
<Hell...@yourpipesaremypipes.org> wrote:

>On Tue, 13 Dec 2011 17:57:24 -0800, John Larkin
><jjla...@highNOTlandTHIStechnologyPART.com> wrote:
>
>>On Tue, 13 Dec 2011 17:52:48 -0800, Hellequin
>><Hell...@yourpipesaremypipes.org> wrote:
>>
>>>On Tue, 13 Dec 2011 17:42:32 -0800, John Larkin
>>><jjla...@highNOTlandTHIStechnologyPART.com> wrote:
>>>
>>>> Police cars in San Francisco,
>>>>Berkeley and Pasadena began to equip their vehicles with radio
>>>>receivers. Again, these were one-way radios.
>>>
>>> Now look at my remark again, idiot.
>>
>>Look at the stuff you snipped, moron.
>>
>>Two-way in 1933.
>>
>>AlwaysWrong.
>>
>>John
>
> I said they were not talking to each other. They weren't. Period.
>It doesn't have a goddamned thing to do with something snipped, idiot.
>
> They were receive only at first, and that reception was from the
>dispatcher only, and even when they went to transceivers, they
>communicated with the dispatcher, not each other.

And you claim this was true throughout the 1930s?

John

VWWall

unread,
Dec 13, 2011, 11:00:38 PM12/13/11
to
Spehro Pefhany wrote:
> On Tue, 13 Dec 2011 17:06:27 -0800, the renowned Hellequin
> <Hell...@yourpipesaremypipes.org> wrote:
>
>> On Tue, 13 Dec 2011 09:12:03 -0800, VWWall <vw...@large.invalid> wrote:
>>
>>> but heated the cathode sleeve
>>> around them. This was the element that produced the electron stream
>>> that made the tubes work.
>> No shit, Sherlock.
>>
>> The filament was never meant to be the emitting element. They were
>> always meant to heat a nearby electrical element. The only reason one
>> sees them on a schematic is because they are heated by an electrical
>> current. They perform no electrical function however. It is purely
>> mechanical, and those mechanics allow the tube to operate in its
>> electrical function properly.
>
> This four-pin one is popular with audiop**ls.
>
> http://www.mif.pg.gda.pl/homepages/frank/sheets/084/3/300B.pdf
>
> eg.
> http://www.6moons.com/audioreviews/tri/tri.html
>
Maybe this contributes to their popularity:

"The most significant difference arises because the voltage along the
filament is not constant, but varies from one end to the other by the
applied filament potential. Although this potential is small, it must be
remembered that the effective plate voltage as seen at the cathode
(filament) is also small. For example, a 300B operating under quiescent
conditions of 350V and 90mA, with –60V on the grid, has a potential as
seen at the cathode of around 15V, against a filament voltage of 5V. At
the negative extreme of grid voltage, modulated by the signal, this
effective voltage will drop close to or even below 5V."

I bet I could sell this fact to audiofools as being the reason 300Bs are
good in audio amplifiers!

I built an amp with 300Bs about fifty years ago. It did sound pretty
good! I have a couple of the tubes still and at the price they get on
eBay I should sell them.

--
Virg Wall

Hellequin

unread,
Dec 14, 2011, 12:45:59 AM12/14/11
to
On Tue, 13 Dec 2011 20:00:38 -0800, VWWall <vw...@large.invalid> wrote:

> I have a couple of the tubes still and at the price they get on
>eBay I should sell them.

The most intelligent thing you have said.
Message has been deleted
Message has been deleted

Adrian Jansen

unread,
Dec 14, 2011, 5:31:14 PM12/14/11
to

On 15/12/2011 2:41 AM, Fred Abse wrote:
> On Mon, 12 Dec 2011 22:35:43 -0800, RST Engineering wrote:
>
>> I could be wrong. I've been wrong before. But to the best of my
>> recollection the '53 Ford was the first 12 volt electrical system.
>
> European cars mainly used 12V systems as far back as the 1930s.
>
I dont remember specifically any European cars from then except
Volkswagen ( 1950's ), which was 6 volt, but the English Fords, Morris
and Austin certainly still had 6 volt systems in the 1950's. They
were all renowned for having extremely poor lights.

A google search would probably give you a whole lot more info.

--
Regards,

Adrian Jansen adrianjansen at internode dot on dot net
Note reply address is invalid, convert address above to machine form.

John Larkin

unread,
Dec 14, 2011, 5:41:29 PM12/14/11
to
On Wed, 14 Dec 2011 08:41:31 -0800, Fred Abse
<excret...@invalid.invalid> wrote:

>On Mon, 12 Dec 2011 22:35:43 -0800, RST Engineering wrote:
>
>> I could be wrong. I've been wrong before. But to the best of my
>> recollection the '53 Ford was the first 12 volt electrical system.
>
>European cars mainly used 12V systems as far back as the 1930s.

My Austin-Healey Sprite, ca 1969, was 6 volts, positive ground. Of
course, it was an antique when I bought it, brand new.

John

John Fields

unread,
Dec 16, 2011, 7:07:43 AM12/16/11
to
On Tue, 13 Dec 2011 12:26:21 -0500, ehsjr <eh...@nospamverizon.net>
wrote:

>John Fields wrote:
>> On Mon, 12 Dec 2011 16:45:03 -0800, Hellequin
>> <Hell...@yourpipesaremypipes.org> wrote:
>>
>>
>>>On Mon, 12 Dec 2011 14:44:59 -0800, RST Engineering <jwe...@gmail.com>
>>>wrote:
>>
>>
>>>>The all-American 5 used a 50C5 audio power, 35W4 rectifier, 12BE6
>>>>RF-Converter, 12BA6 IF, 12AT6 detector-audio preamp. Add up the
>>>>filament voltages for an interesting look at a transformerless line
>>>>voltage receiver.
>>>
>>> They are all 6.3 volt filaments.
>>
>>
>> ---
>> It could be argued that the 12V filaments are really two 6V filaments
>> in series with their ends and their junction brought out of the tube,
>> but the 50C5 sports a 50V filament and the 35W4 a 35V one.
>>
>>
>
>Yup. As I recall, the first digits always* indicated the filament
>voltage.
>
>* I think there were some exceptions, like tubes with the single
>digit 1 before the letter. The 1 meant ~1.5 volts, not 1 volt,
>if my very fuzzy memory is correct.
>
>Ed

---
Close ;)

Most of the 1XX tube filaments are rated for a nominal 1.25V, with the
warning: "Under no circumstances should voltage fall below 1.05V or
exceed 1.45V" as part of the spec.

A notable exception is the 1V2, with a low of 0.525V, a nominal of
0.625V, and a high of 0.725V.

--
JF
Message has been deleted

josephkk

unread,
Dec 16, 2011, 8:35:29 PM12/16/11
to
On Tue, 13 Dec 2011 08:14:11 -0800, John Larkin
<jjla...@highNOTlandTHIStechnologyPART.com> wrote:

>On Tue, 13 Dec 2011 07:10:07 -0800, SMS <scharf...@geemail.com>
>wrote:
>
>>On 12/11/2011 5:16 AM, mpm wrote:
>>> On Dec 10, 7:30 pm, j...@myplace.com wrote:
>>>> The old tube stuff always had 6.3 volts on the filaments (except those
>>>> with other voltages). I always wondered why they used the ".3". Why
>>>> not just an even 6 volts, or 6 and a half? Just curious if there was
>>>> actually some real reason for the .3 volts?
>>>
>>> When you figure this out, could you then let us know why they charge
>>> the $0.009 cents on each gallon of gasoline (in the US)?
>>
>>That's a legacy from back when gasoline prices were in cents and tenths
>>of cents. The tenths were not always set to nine, and a difference of
>>tenths of a cent represented a substantial percentage of the per gallon
>>price. It's rather silly now.
>>
>>I recall when the oil companies first began jacking up the price of
>>gasoline and some pumps could not go over 99.9. Some stations were
>>setting their pumps to half the per gallon price (xx.4) and then
>>doubling the pump total to yy.8.
>
>Prices in the US very often end in "9". That avoids an increment of
>sales tax.
>
>John

There is also the advertising baloney part to be able to say "Under twenty
dollars". Hmm, yes, it is; just not significantly so.

?-)

RST Engineering

unread,
Dec 17, 2011, 1:03:13 PM12/17/11
to
On Thu, 15 Dec 2011 08:31:14 +1000, Adrian Jansen <adr...@qq.vv.net>
wrote:

>
>On 15/12/2011 2:41 AM, Fred Abse wrote:
>> On Mon, 12 Dec 2011 22:35:43 -0800, RST Engineering wrote:
>>
>>> I could be wrong. I've been wrong before. But to the best of my
>>> recollection the '53 Ford was the first 12 volt electrical system.
>>
>> European cars mainly used 12V systems as far back as the 1930s.
>>
>I dont remember specifically any European cars from then except
>Volkswagen ( 1950's ), which was 6 volt, but the English Fords, Morris
>and Austin certainly still had 6 volt systems in the 1950's. They
>were all renowned for having extremely poor lights.


That's the reason the Brits drink their beer warm ... Lucas
refrigerators.

Jim

Don Lancaster

unread,
Dec 19, 2011, 10:52:00 AM12/19/11
to
Critical price thresholds are very real at auctions.

Particularly the "don't go there's" of $20, $100,, and $1000.

More at < http://www.tinaja.com/ahsamp1.asp >


--
Many thanks,

Don Lancaster voice phone: (928)428-4073
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
rss: http://www.tinaja.com/whtnu.xml email: d...@tinaja.com

Please visit my GURU's LAIR web site at http://www.tinaja.com

David Lesher

unread,
Feb 11, 2012, 2:02:29 AM2/11/12
to
Hellequin <Hell...@yourpipesaremypipes.org> writes:



> The police were not radio-ing each other in the 30s.

<http://www.wb6nvh.com/CHP/CHP1.htm>
--
A host is a host from coast to coast.................wb8foz@nrk.com
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

christofire

unread,
Feb 11, 2012, 5:58:52 PM2/11/12
to

"David Lesher" <wb8...@panix.com> wrote in message
news:jh53q5$371$1...@reader1.panix.com...
> Hellequin <Hell...@yourpipesaremypipes.org> writes:
>
>
>
>> The police were not radio-ing each other in the 30s.
>

Some disagree: http://apps.detnews.com/apps/history/index.php?id=35
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