OT.... but I need help

On 02/11/2012 19:56, Gene E. Bloch wrote:
On Fri, 2 Nov 2012 07:29:38 +0000, J. P. Gilliver (John) wrote:

In message , Gene E. Bloch
writes:
On Thu, 01 Nov 2012 19:59:41 -0400, charlie wrote:

These days, the power companies don't necessarily do what they used to
do to keep synchronous motor driven clocks on or close to the correct time.

I have in the last couple of years tried to buy a synchronous motor
clock, without success.

IIRC, I wanted to run such a clock on the output of a 12 VDC to 120 VAC
inverter to see how accurate the frequency was.
[]
If that's all you want it for, the cheapest type of digital alarm clocks
- the sort with four LED digits, and a beep alarm and sometimes a radio
- still tend to count mains (line) cycles. Probably impossible to tell
before purchase, though. I'd have thought they'd have switched to quartz
like everyone else by now, but presumably the circuit design (it's
basically one chip, for the clock parts anyway) stabilised some decades
ago, and there's been no reason to alter it.

Interesting. I had thought they all used xtals these days (or even RC
networks - what else could explain the lousy timekeeping of a couple
I've seen?).

Thanks.


We have bought an alarm. It obviously worked on a xtal base. Each day it
lagged 1 minute. So we changed it for another one. That one lagged less,
5 minutes per week. What does it say about using a xtall? Forget it.
It's all cheap Chinese ****.

Fokke

On 02/11/2012 20:42, Gene E. Bloch wrote:
On Fri, 02 Nov 2012 18:59:39 +0000, Ed Cryer wrote:

Paul wrote:
Ed Cryer wrote:
Drew wrote:
On 11/1/2012 12:04 PM, Ed Cryer wrote:
In our local sports centre swimming pool there's a clock on the
wall. It
keeps good time. I've relied on it for years to time myself.
However, every day at 4-00pm exactly it goes into overdrive, and sweeps
round covering many hours in a few seconds. Then it resets at just
after
4-00pm, and continues normally.

I've pointed it out to many fellow swimmers; and they stare in
amazement, raised eyebrows and a dim expression over the facial
features
and say they don't know.

The other day I finally gave in and asked at Reception what it was all
about. She told me that that was the only clock in the Centre that did
that, that they weren't interconnected and that she didn't know why.

My best guess is that it's a radio clock, and it self-adjust every day
at 4-00pm. But I've googled for "clock speeds up at 4-00pm" and the
like
and haven't found the answer.

Some one here must have met one of these things. If so then let me know
more.

Ed

Possible atomic clock of some kind?

I have a strong suspicion you're right here. Everybody else seems to
have gone for radio-control (I did myself as first guess), but look
what googling has produced.

It looks just like this;
http://www.walmart.com/ip/14-Analog-...Pearl/13443480

And then take a look at these hits for images on "Analog Atomic Wall
Clock"; there are zillions.
http://tinyurl.com/bt95lv3

There must be quite a lot of these things in use around the world. The
write-up says;
Radio-Controlled Atomic Time
Automatically sets to exact time
Accurate to the second
Automatically updates for daylight saving time (on/off option)
4 time zone settings
14'' Plastic Frame
Simple Operation: Insert One AA Alkaline Battery (not included)
After signal is received, press Time Zone button to set
Four Time Zone Settings
Daylight Saving Time Option On/Off
Manual Reset Button

Ed

According to this, that product uses WWVB.

http://www.lacrosse-clock.com/lacrosse_technology.htm

The signal strength varies through the day. So if it
was having a reception problem, you'd wait until the
signal reached peak strength, to see if the clock could
pick it up.

http://www.nist.gov/pml/div688/grp40/radioclocks.cfm

( http://en.wikipedia.org/wiki/WWVB )

Amazing it runs off one AA alkaline cell. So while
you don't have to set the time, the battery is still
going to need changing.

Paul



I find that hard to believe, too. My little Acctim digital radio clock
needs two AAs. But it also displays date, temp and phase of moon. Mind
you, I can't recall having ever changed the batts since I got the thing.

Ed

Clearly the second battery is for the moon phase :-)

Imagine the battery situation if these things had to use vacuum tubes
(valves).


Well, it would only need 200 batteries to reach the anode voltage.

Fokke

Fokke Nauta wrote:
On 01/11/2012 23:52, Paul wrote:
Fokke Nauta wrote:
On 01/11/2012 20:04, Ed Cryer wrote:
In our local sports centre swimming pool there's a clock on the
wall. It
keeps good time. I've relied on it for years to time myself.
However, every day at 4-00pm exactly it goes into overdrive, and sweeps
round covering many hours in a few seconds. Then it resets at just
after
4-00pm, and continues normally.

I've pointed it out to many fellow swimmers; and they stare in
amazement, raised eyebrows and a dim expression over the facial
features
and say they don't know.

The other day I finally gave in and asked at Reception what it was all
about. She told me that that was the only clock in the Centre that did
that, that they weren't interconnected and that she didn't know why.

My best guess is that it's a radio clock, and it self-adjust every day
at 4-00pm. But I've googled for "clock speeds up at 4-00pm" and the
like
and haven't found the answer.

Some one here must have met one of these things. If so then let me know
more.

Ed

Well, we got a radio controlled alarm here. It should be synced by a
Frankfurt radio time transmittor. Really state of the art. I would
call it state of a fart. Many times it shows a different time. Always
a surpise when you look for the time. It varies from minus to plus a
few hours.
So your clock (radio controlled as well) ain't too bad.

Fokke

In North America, there is WWV.

http://en.wikipedia.org/wiki/WWV_(radio_station)

There is also GPS, but that's at a higher frequency, and may be
harder to receive inside a building.

Whatever radio source is uses, the format of signal would have
to be simple enough, for a cheap synchronization design. With
processors being as cheap as they are now, that wouldn't present
a problem today. But might have been an issue when that particular
clock was built.

This device claims to set itself via radio signal.

http://www.amazon.com/Sangean-Americ.../dp/B0010HUAIO



"Radio Controlled clock available for DCF/WWVB/MSF/JJY"

http://en.wikipedia.org/wiki/DCF77
http://en.wikipedia.org/wiki/MSF_time_signal
http://en.wikipedia.org/wiki/JJY

Interesting collection of frequencies. The low frequencies
are in the same range as the ones submarines use. Whereas
the WWV thing is shortwave.

Paul

Hey, our alarm clock listens to DCF77. Wasn't aware of that!

Interesting info!

Fokke


What I missed when I posted that, is WWV is shortwave, while
WWVB is the lower frequency. So the DCF/WWVB/MSF/JJY signals
are around 100KHz or less.

This article, lists a few more transmitters. There are
more than those four above.

http://www.edn-europe.com/receiveran...48+Europe.html

Paul

On 02/11/2012 15:29, Justin wrote:
On 11/1/2012 3:04 PM, Ed Cryer wrote:
In our local sports centre swimming pool there's a clock on the wall. It
keeps good time. I've relied on it for years to time myself.
However, every day at 4-00pm exactly it goes into overdrive, and sweeps
round covering many hours in a few seconds. Then it resets at just after
4-00pm, and continues normally.

I've pointed it out to many fellow swimmers; and they stare in
amazement, raised eyebrows and a dim expression over the facial features
and say they don't know.

The other day I finally gave in and asked at Reception what it was all
about. She told me that that was the only clock in the Centre that did
that, that they weren't interconnected and that she didn't know why.

My best guess is that it's a radio clock, and it self-adjust every day
at 4-00pm. But I've googled for "clock speeds up at 4-00pm" and the like
and haven't found the answer.

Some one here must have met one of these things. If so then let me know
more.

Ed


Your kids are swimming so fast, they're slowing time and sending out
"time quakes" that interfere with the clock.

Or they are swimming faster (300,000 km/sec) and are ahead of time?

Fokke

In message , Ed Cryer
writes:
Drew wrote:
[]
Possible atomic clock of some kind?

I have a strong suspicion you're right here. Everybody else seems to
have gone for radio-control (I did myself as first guess), but look
what googling has produced.
[]
Bad (I'd say bordering on illegal, but it must be only bordering as
they've been doing it for ages now) use of advertising copy.

These clocks are _not_ atomic; they use radio signals from a reference
elsewhere, which _may_ use an atomic clock mechanism for reference.

A true atomic clock is very bulky, extremely expensive, and somewhat
heavy.

What's more, they advertise these clocks (and watches) as "accurate to a
second in a million years" (or that sort of thing). Which, of course,
they're not: the clock they're _linked_ to _may_ be. Can't see how they
get away with such claims, but they obviously do.
--
J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

Abandon hope, all ye who ENTER here.

In message , Fokke Nauta
writes:
On 02/11/2012 20:42, Gene E. Bloch wrote:
On Fri, 02 Nov 2012 18:59:39 +0000, Ed Cryer wrote:
[]
I find that hard to believe, too. My little Acctim digital radio clock
needs two AAs. But it also displays date, temp and phase of moon. Mind
you, I can't recall having ever changed the batts since I got the thing.

Ed

My little Auriol has all of those except the moon phase, and contains
two AAAs; they're the cheap (zinc-carbon?) kind, are the ones that came
with it, and have been in since I got the clock.

Clearly the second battery is for the moon phase :-)

(-:

Imagine the battery situation if these things had to use vacuum tubes
(valves).


Well, it would only need 200 batteries to reach the anode voltage.

Fokke

One battery, containing 200 cells ... though single cells do tend to be
referred to as "batteries" these days. A car battery, or a PP3 or PP9,
is a true battery; AA, AAA, C, D, etc. are cells.
--
J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

"He hasn't one redeeming vice." - Oscar Wilde

Ed Cryer wrote:
In our local sports centre swimming pool there's a clock on the wall. It
keeps good time. I've relied on it for years to time myself.
However, every day at 4-00pm exactly it goes into overdrive, and sweeps
round covering many hours in a few seconds. Then it resets at just after
4-00pm, and continues normally.

I've pointed it out to many fellow swimmers; and they stare in
amazement, raised eyebrows and a dim expression over the facial features
and say they don't know.

The other day I finally gave in and asked at Reception what it was all
about. She told me that that was the only clock in the Centre that did
that, that they weren't interconnected and that she didn't know why.

My best guess is that it's a radio clock, and it self-adjust every day
at 4-00pm. But I've googled for "clock speeds up at 4-00pm" and the like
and haven't found the answer.

Some one here must have met one of these things. If so then let me know
more.

Ed

It's just an "atomic time" clock resetting itself when it gets a half
second out of time, it can't go backwards so it spins around until it
get to where it's supposed to be. One of mine does the same thing
sometimes. No biggie just doing what they are supposed to do. Trains
were the main reason to standardize time way way back. An interesting
read if you like that kind of thing.
http://www.webexhibits.org/daylightsaving/d.html

On Fri, 02 Nov 2012 22:19:08 +0100, Fokke Nauta wrote:

On 02/11/2012 19:56, Gene E. Bloch wrote:
On Fri, 2 Nov 2012 07:29:38 +0000, J. P. Gilliver (John) wrote:

In message , Gene E. Bloch
writes:
On Thu, 01 Nov 2012 19:59:41 -0400, charlie wrote:

These days, the power companies don't necessarily do what they used to
do to keep synchronous motor driven clocks on or close to the correct time.

I have in the last couple of years tried to buy a synchronous motor
clock, without success.

IIRC, I wanted to run such a clock on the output of a 12 VDC to 120 VAC
inverter to see how accurate the frequency was.
[]
If that's all you want it for, the cheapest type of digital alarm clocks
- the sort with four LED digits, and a beep alarm and sometimes a radio
- still tend to count mains (line) cycles. Probably impossible to tell
before purchase, though. I'd have thought they'd have switched to quartz
like everyone else by now, but presumably the circuit design (it's
basically one chip, for the clock parts anyway) stabilised some decades
ago, and there's been no reason to alter it.

Interesting. I had thought they all used xtals these days (or even RC
networks - what else could explain the lousy timekeeping of a couple
I've seen?).

Thanks.


We have bought an alarm. It obviously worked on a xtal base. Each day it
lagged 1 minute. So we changed it for another one. That one lagged less,
5 minutes per week. What does it say about using a xtall? Forget it.
It's all cheap Chinese ****.

Fokke

There are crystals and there are crystals.

I often see clocks that are accurate to a few seconds a day. We just got
a kitchen timer that also has a clock in it; it cost $15US, and is
accurate to about 3 seconds a week.

So try a different brand :-)

--
Gene E. Bloch (Stumbling Bloch)

On Fri, 02 Nov 2012 22:32:37 +0100, Fokke Nauta wrote:

On 02/11/2012 20:42, Gene E. Bloch wrote:
On Fri, 02 Nov 2012 18:59:39 +0000, Ed Cryer wrote:

Paul wrote:
Ed Cryer wrote:
Drew wrote:
On 11/1/2012 12:04 PM, Ed Cryer wrote:
In our local sports centre swimming pool there's a clock on the
wall. It
keeps good time. I've relied on it for years to time myself.
However, every day at 4-00pm exactly it goes into overdrive, and sweeps
round covering many hours in a few seconds. Then it resets at just
after
4-00pm, and continues normally.

I've pointed it out to many fellow swimmers; and they stare in
amazement, raised eyebrows and a dim expression over the facial
features
and say they don't know.

The other day I finally gave in and asked at Reception what it was all
about. She told me that that was the only clock in the Centre that did
that, that they weren't interconnected and that she didn't know why.

My best guess is that it's a radio clock, and it self-adjust every day
at 4-00pm. But I've googled for "clock speeds up at 4-00pm" and the
like
and haven't found the answer.

Some one here must have met one of these things. If so then let me know
more.

Ed

Possible atomic clock of some kind?

I have a strong suspicion you're right here. Everybody else seems to
have gone for radio-control (I did myself as first guess), but look
what googling has produced.

It looks just like this;
http://www.walmart.com/ip/14-Analog-...Pearl/13443480

And then take a look at these hits for images on "Analog Atomic Wall
Clock"; there are zillions.
http://tinyurl.com/bt95lv3

There must be quite a lot of these things in use around the world. The
write-up says;
Radio-Controlled Atomic Time
Automatically sets to exact time
Accurate to the second
Automatically updates for daylight saving time (on/off option)
4 time zone settings
14'' Plastic Frame
Simple Operation: Insert One AA Alkaline Battery (not included)
After signal is received, press Time Zone button to set
Four Time Zone Settings
Daylight Saving Time Option On/Off
Manual Reset Button

Ed

According to this, that product uses WWVB.

http://www.lacrosse-clock.com/lacrosse_technology.htm

The signal strength varies through the day. So if it
was having a reception problem, you'd wait until the
signal reached peak strength, to see if the clock could
pick it up.

http://www.nist.gov/pml/div688/grp40/radioclocks.cfm

( http://en.wikipedia.org/wiki/WWVB )

Amazing it runs off one AA alkaline cell. So while
you don't have to set the time, the battery is still
going to need changing.

Paul



I find that hard to believe, too. My little Acctim digital radio clock
needs two AAs. But it also displays date, temp and phase of moon. Mind
you, I can't recall having ever changed the batts since I got the thing.

Ed

Clearly the second battery is for the moon phase :-)

Imagine the battery situation if these things had to use vacuum tubes
(valves).


Well, it would only need 200 batteries to reach the anode voltage.

Fokke

Good one!

In the old days, they made batteries with about 60 cells and used tubes
that needed a B+ (that's engineer's slang for anode voltage) of 90
volts.

--
Gene E. Bloch (Stumbling Bloch)

On Fri, 2 Nov 2012 21:40:54 +0000, J. P. Gilliver (John) wrote:

In message , Ed Cryer
writes:
Drew wrote:
[]
Possible atomic clock of some kind?

I have a strong suspicion you're right here. Everybody else seems to
have gone for radio-control (I did myself as first guess), but look
what googling has produced.
[]
Bad (I'd say bordering on illegal, but it must be only bordering as
they've been doing it for ages now) use of advertising copy.

These clocks are _not_ atomic; they use radio signals from a reference
elsewhere, which _may_ use an atomic clock mechanism for reference.

A true atomic clock is very bulky, extremely expensive, and somewhat
heavy.

What's more, they advertise these clocks (and watches) as "accurate to a
second in a million years" (or that sort of thing). Which, of course,
they're not: the clock they're _linked_ to _may_ be. Can't see how they
get away with such claims, but they obviously do.

Well, people like you and me notice it, so they aren't really getting
away with it :-)

--
Gene E. Bloch (Stumbling Bloch)

J. P. Gilliver (John) wrote:
In message , Fokke Nauta
writes:
On 02/11/2012 20:42, Gene E. Bloch wrote:
On Fri, 02 Nov 2012 18:59:39 +0000, Ed Cryer wrote:
[]
I find that hard to believe, too. My little Acctim digital radio clock
needs two AAs. But it also displays date, temp and phase of moon. Mind
you, I can't recall having ever changed the batts since I got the
thing.

Ed

My little Auriol has all of those except the moon phase, and contains
two AAAs; they're the cheap (zinc-carbon?) kind, are the ones that came
with it, and have been in since I got the clock.

Clearly the second battery is for the moon phase :-)

(-:

Imagine the battery situation if these things had to use vacuum tubes
(valves).


Well, it would only need 200 batteries to reach the anode voltage.

Fokke

One battery, containing 200 cells ... though single cells do tend to be
referred to as "batteries" these days. A car battery, or a PP3 or PP9,
is a true battery; AA, AAA, C, D, etc. are cells.

On old vacuum radio gear, there were two sets of batteries.
There were large "cylinders" to be used for filaments.
And "cubes" to power B+ voltage. You might need two
of these "cubes" to get enough B+ for mobile operation.
These are 67.5 volts each.

http://www.antiqueradios.com/forums/...?f=19&t=196817

Something like this might have been for filaments. The
filaments would likely be in parallel. Whereas some
radios powered from the wall, the filaments were in
series.

http://www.radiolaguy.com/images/mis...A-cells-x4.jpg

This is just a vague recollection of some stuff my father
brought home when I was quite young. All the batteries
in this case, were flat, so there was no chance to
verify how many batteries were needed to run it. I
could have done some serious damage as an experimenter,
if those B+ batteries were working.

Paul

On 11/1/2012 5:51 PM, Ed Cryer wrote:
Bob I wrote:
Take a close look at the face, and see who manufactured it, then Google.

On 11/1/2012 2:04 PM, Ed Cryer wrote:
In our local sports centre swimming pool there's a clock on the wall. It
keeps good time. I've relied on it for years to time myself.
However, every day at 4-00pm exactly it goes into overdrive, and sweeps
round covering many hours in a few seconds. Then it resets at just after
4-00pm, and continues normally.

I've pointed it out to many fellow swimmers; and they stare in
amazement, raised eyebrows and a dim expression over the facial features
and say they don't know.

The other day I finally gave in and asked at Reception what it was all
about. She told me that that was the only clock in the Centre that did
that, that they weren't interconnected and that she didn't know why.

My best guess is that it's a radio clock, and it self-adjust every day
at 4-00pm. But I've googled for "clock speeds up at 4-00pm" and the like
and haven't found the answer.

Some one here must have met one of these things. If so then let me know
more.

Ed

I thought of that. But I'd need a ladder at least ten feet high. It's
almost at the top of the wall.


Binoculars? Many years ago, I saw something similar happen, clock at the
school ran slightly fast and at sync time it would advance 11 hours and
59 minutes to lose the 1 minute it was ahead. (or in reality 12 hours as
it took almost a minute to spin the 12 revolutions)

Gene E. Bloch wrote:
On Fri, 02 Nov 2012 22:19:08 +0100, Fokke Nauta wrote:

On 02/11/2012 19:56, Gene E. Bloch wrote:
On Fri, 2 Nov 2012 07:29:38 +0000, J. P. Gilliver (John) wrote:

In message , Gene E. Bloch
writes:
On Thu, 01 Nov 2012 19:59:41 -0400, charlie wrote:

These days, the power companies don't necessarily do what they used to
do to keep synchronous motor driven clocks on or close to the correct time.
I have in the last couple of years tried to buy a synchronous motor
clock, without success.

IIRC, I wanted to run such a clock on the output of a 12 VDC to 120 VAC
inverter to see how accurate the frequency was.
[]
If that's all you want it for, the cheapest type of digital alarm clocks
- the sort with four LED digits, and a beep alarm and sometimes a radio
- still tend to count mains (line) cycles. Probably impossible to tell
before purchase, though. I'd have thought they'd have switched to quartz
like everyone else by now, but presumably the circuit design (it's
basically one chip, for the clock parts anyway) stabilised some decades
ago, and there's been no reason to alter it.
Interesting. I had thought they all used xtals these days (or even RC
networks - what else could explain the lousy timekeeping of a couple
I've seen?).

Thanks.

We have bought an alarm. It obviously worked on a xtal base. Each day it
lagged 1 minute. So we changed it for another one. That one lagged less,
5 minutes per week. What does it say about using a xtall? Forget it.
It's all cheap Chinese ****.

Fokke

There are crystals and there are crystals.

I often see clocks that are accurate to a few seconds a day. We just got
a kitchen timer that also has a clock in it; it cost $15US, and is
accurate to about 3 seconds a week.

So try a different brand :-)


Quartz oscillators can have a trimmer cap in the design. And
that can be used to trim out the initial tolerance. My digital
watch has one of those in it.

In the example here, the "5 to 35 picofarad" capacitor in the lower
left hand corner of the image, is the trimmer cap. In a watch,
it's a circle shaped thing, with room for s slot head screwdriver
to turn the trimmer.

http://www.seekic.com/uploadfile/ic-...0223133731.gif

If a design leaves a factory, without any trimming capability,
the trimming cap is replaced with a fixed value cap. And then,
it's the initial tolerance of the quartz crystal that counts.

Quartz crystals also "age" with time, so there is more to
it than just nulling the initial tolerance out. (You don't
have to read the whole section - just marvel at the size of
the article :-) )

http://en.wikipedia.org/wiki/Crystal...lity_and_aging

And if you don't like quartz crystals, they do make pretty
small atomic clocks.

http://www.popsci.com/technology/art...-ever-now-sale

Paul

In message , Paul
writes:
[]
And if you don't like quartz crystals, they do make pretty
small atomic clocks.

http://www.popsci.com/technology/art...atomic-clock-e
ver-now-sale

Paul

I hadn't realised the technology had come on so! Mind you, at a tenth of
a watt, that one's not going to run for long on an AA cell or two - and
I don't have $1500 to spare either ... (-: [Still impressive, though.]
--
J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

Or Margo Leadbetter sayig "Jerry" in a voice that could melt a box of After
Eights. - David Butcher in RT, 12-18 May 2012.

In message , Paul
writes:
J. P. Gilliver (John) wrote:
In message , Fokke Nauta
writes:
[]
Well, it would only need 200 batteries to reach the anode voltage.

Fokke
One battery, containing 200 cells ... though single cells do tend to
be referred to as "batteries" these days. A car battery, or a PP3 or
PP9, is a true battery; AA, AAA, C, D, etc. are cells.

On old vacuum radio gear, there were two sets of batteries.

No, two batteries (-:. [That was the point I was making - "battery"
strictly means, or used to, "a set of cells".]

There were large "cylinders" to be used for filaments.

Yes, the filaments - or heaters as they tend to be called in UK -
generally ran on 6.3V (three lead-acid cells in series), though some
valves had 2V or even 1.5V heaters. In UK (allegedly - I'm not old
enough to remember this!), people without mains electricity had an
"accumulator" - presumably such a 6V battery - which they took to a
local shop to get charged. (Apparently often a local cycle shop.)

And "cubes" to power B+ voltage. You might need two
of these "cubes" to get enough B+ for mobile operation.
[]
I can _just_ - this would have been in the 1970s, in a rural town in
north England - remember seeing such batteries on sale. About the shape
(and size, and IIRR weight!) of a house brick, with a three prong
connector in the middle. (I have a vague memory that it might have been
90V, but it could have been two hundred and something - or even two
different voltages, given the three prong connector.) [By the way, I
think the term "B+ voltage" is US; I'm not sure what term was used in
UK, maybe HT.]

filaments would likely be in parallel. Whereas some
radios powered from the wall, the filaments were in
series.

Indeed. If in parallel, they could be different current ratings but had
to be the same voltage (e. g. for battery/cell powered sets); if in
series, they needed to be the same current rating but could be different
voltages (provided they all added up to the supply voltage - sometimes
with a big green series resistor to drop some of it and/or limit the on
surge!).
[]
This is just a vague recollection of some stuff my father
brought home when I was quite young. All the batteries
in this case, were flat, so there was no chance to
verify how many batteries were needed to run it. I

Well, unless you wanted to keep them as a museum exhibit, you could find
out by ripping the flat batteries apart to see how many cells they
contained (which I expect would have been ordinary 1.5 volt cells,
though of unusual shapes). I'd have thought they'd have the voltage
printed on them, though.

could have done some serious damage as an experimenter,
if those B+ batteries were working.

Paul
(-:

A fascinating diversion, this, for something like the Windows 7
newsgroup - I hope the rest don't mind! They might also enjoy
http://www.bvwtm.org.uk/tour/.
--
J. P. Gilliver. UMRA: 1960/1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

Or Margo Leadbetter sayig "Jerry" in a voice that could melt a box of After
Eights. - David Butcher in RT, 12-18 May 2012.