Old, Old panel meters, discovered in a box today..

Zelandeth

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Kinda a cross between electronics and history here...moderators feel free to move this if you think I put it in the wrong place.

Was actually looking for a computer PSU this afternoon in the loft, and spotted an old cardboard box in the corner I'd never noticed before. I decided to brave the extremely high probability of falling through the lounge ceiling to get to it, because I was curious (like that's something that hasn't got me into trouble a zillion times before).

As it turned out, this box was full of old (really old) panel meters. I've included pics of them below. Most are pretty conventional volt/ammters, though there's a runtime meter and frequency meter which are a bit more obscure I think. I've only been able to test the one ammeter, as everything else seems to require obscure power supplies (120VAC or RF frequencies). So I can't say whether they work or not.

ammetersmall.jpg

This may actually have the date printed on the face, as it reads 1945 in the bottom left corner. On the back thre is white printed text reading:

1592423
D
Z.A.21547 W.P. Don't know if that means anything to anyone.

ammetersquare.jpg


Another RF ammeter. At least this one actually has a logo on it. It, like the one above also has what could be a year on the face, reading 1942 in this case. Text on the back of this one reads 44o977.

frequencymeter.jpg

J-B-T Model 31-FX Frequency Meter.
Now this one's a bit more obscure - and initially I was at a loss to explain how it would work. Think I've figured it out now though. Those little white rectangles are actually connected to metal arms, these disappear back into the housing further than I can see. I am guessing that they're all connected to something which will vibrate at the supply frequency - some being sprung so that they resonate at specifically tuned frequency. This I'm guessing will mean that some will move further than others, effectively meaning a curve would be visible there on the display, with the widest point indicating the supply frequency. All guesswork, so don't quote me on it! I'd like to test the theory, but I'm a bit short on 100-130Vac 60Hz supplies.

Text around the edge of the face reads: "Made under Triplett patent No. 2,403,809" and "J-B-T instruments, inc. New Haven, Conn, U.S.A."

kvmeter.jpg

FS 273V DC Kilovoltmeter.

Now, voltmeters...I have a few of them laying around, but this is the first KVmeter I've found! Nor do I actually have a use for a meter reading up to 30kV. Don't know whether I'd trust something that old to deal with those voltages either. Possibly dating from 1942 by the number on the lower left of the face.

milliammeter.jpg

Weston Model 301 DC Milliammeter.
Yes! One I could actually test! And it works too. Accurate to 0.5mA it would appear as well. Face is actually matt silver, not white as it appears in the photo. Text on the face reads: "Weston Electrical Instrument co., LTD., Surrey, England." The number in the lower right corner appears to have been written by hand in Indian Ink, in TINY numbers too, 20504. I have to guess that's a serial number.

runtime.jpg

Aero Model 1001 Runtime meter.

This thing is seriously heavy for its size, and that little display just looks classy. Just like the little tape counters you get on cassette players...but in what appears to be stainless steel. Have to assume this is a simple syncronous motor and gear arrangement. Not sure is the red digit represents 0.1 hours or 1 hour though. And again, no way to test it at present.
Text around the bottom of the meter face reads: "O'Keefe & Merritt Co. Los Angeles, Calif. U.S.A."

Probably bored you all to tears here, if that's the case I'm sorry. I just thought someone might be interested. I know we have collectors of antique radios and such around. Wondering if anyone's familiar with any of these instruments, and knows what sort of place they'd originally have seen service in. And if anyone can date them? I'm at a loss really other than those which have what could be the production year printed on the face.

It's amasing what you can find when you're not looking, isn't it!

Also, any of these likely to actually be worth anything? I doubt it, but figure it's worth asking.
 

Mags

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Re: Old, Old panel meters, discovered in a box tod

Wow wouldnt these be considered antiques? If you can find the maker of all of these meters, then they might go for some. Or if you plan on keeping them for show, you can polish em!
 

idleprocess

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Re: Old, Old panel meters, discovered in a box tod

LED-FX:
Could you fix that link please? Either shorten it at tinyurl or take advantage of UBB like I did with the tinyurl link?

Ex:
<font class="small">Code:</font><hr /><pre>tinyurl</pre><hr />
 

idleprocess

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Re: Old, Old panel meters, discovered in a box tod

120VAC is standard household voltage over here in this forgotten corner of the world... /ubbthreads/images/graemlins/grin.gif
 

KC2IXE

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Re: Old, Old panel meters, discovered in a box tod

Basically, the freq meter works as you state - it vibrates at the freq it sees

The one below it (the Kilovolt meter) is British - note the broadarrow on the face
 

Jack_Crow

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Re: Old, Old panel meters, discovered in a box tod

KC2IXE,
The RF amp meter if you look at it close is a thermocouple type. I gather if you look close the terminals are of two different metals.

The big "K" is a give away. K type thermocouples are made of copper and 'constintin'(sp?) anyhow you can look it up.

There are several ways of measuring RF power. One is with an in line meter like a Bird Electric. Another is what's known as caliremitery. In other words, heat up a load and take it's temp. So if you hung a thermocouple on an rf load and applyed power, that power would be expressed as RF watts.

That' show many of the 'thermistor mounts' in microwave measurments work. It measures all the power coming from a transmitter. Primary, harmonics, residual dc, the works. That's the best guess until I can look at it by hand.

There is most likely more. For example if this was part of an inline system, there might be a directional coupler like device that sniffs off a sample of the rf, and that is scaled for a proportional reading. Then again it's something salvaged from mil surplus equipment that was avalable right after wwII.

For what it's worth, that crown causes me a moment's pause. The brits used mostly 75 ohm systems, while the US used 50 ohm rf systems. Do you remember why? It also makes buying european made RF gear a pain in the *** here.

As for the power line frequency meter. Each one of those rods are a tuning fork. For many years there were no electronic circuits that worked w/o dirft at audio frequencies. Remember what is used on very old two way radios for PL encoders and decoders. Motorola called them Vibrasonders, most everybody else called them vibra-twang-ers. They would respond to spicific tones and cause the radios to do something.

You usually see meters like this on electrical generators and such. Most have more 'steps' typically 55 to 65 in one or two hz amounts. I saw these in Iraq on some older gear.

The KV one is cute, most likely of euro origin. Did you see the little symbol for 50 hz??

As another responder said, the run time meter is straight foward. Use a care, by now the motor has not run in what 60 years. If the display stops working and the glass looks smokey, take a hint.

I knew all those years as a calibration tech would come in handy on Jepardy one day.

"Alex, give me compramising positions for 200 please"

Later guys
 

snakebite

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Re: Old, Old panel meters, discovered in a box tod

looks like sombody tore down a big transmitter of some kind.
 

LitFuse

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Re: Old, Old panel meters, discovered in a box tod

I'd list them on eBay, you never know with old instruments, etc. You might be very suprised what someone will pay for these.

Peter
 

chmsam

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Re: Old, Old panel meters, discovered in a box tod

Beautiful stuff! Are any of them illuminated?

BTW, don't polish them -- most of the time antiques lose a lot of value unless they are in original conditon.
 

DarkLight

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Re: Old, Old panel meters, discovered in a box tod

[ QUOTE ]
Mags_despiser said:
Wow wouldnt these be considered antiques? If you can find the maker of all of these meters, then they might go for some. Or if you plan on keeping them for show, you can polish em!

[/ QUOTE ]


Generally NEVER EVER change the finish on an antique item unless you want to make it worth instantly half or less of what it was.
 

Draco_Americanus

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Re: Old, Old panel meters, discovered in a box tod

I like the High Voltage one My self! It would have probly used a remotely mounted voltage divider rather then be directly connected to the source high voltage.
It is odd that it says "d.c. kilovolts" but then has the 50hz, odd.
perhaps you may wish to sell a few of these?
 

Mags

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Re: Old, Old panel meters, discovered in a box tod

[ QUOTE ]
DarkLight said:
[ QUOTE ]
Mags_despiser said:
Wow wouldnt these be considered antiques? If you can find the maker of all of these meters, then they might go for some. Or if you plan on keeping them for show, you can polish em!

[/ QUOTE ]


Generally NEVER EVER change the finish on an antique item unless you want to make it worth instantly half or less of what it was.

[/ QUOTE ]
Sorry, I dont know anything about antiques.... /ubbthreads/images/graemlins/frown.gif
 

MaxaBaker

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Re: Old, Old panel meters, discovered in a box tod

[ QUOTE ]
DarkLight said:
[ QUOTE ]
Mags_despiser said:
Wow wouldnt these be considered antiques? If you can find the maker of all of these meters, then they might go for some. Or if you plan on keeping them for show, you can polish em!

[/ QUOTE ]


Generally NEVER EVER change the finish on an antique item unless you want to make it worth instantly half or less of what it was.

[/ QUOTE ]

Hehe.....my dad is an antique collector and he freaks out when someone touches somehting in my house if they don't ask. One time my brother tried to polish something up for him for his birthday (As you know you DON'T do that!!!). My dad absolutely freaked out but let my brother off since it's the thought that counts /ubbthreads/images/graemlins/grin.gif

Hey, you should take those on Antique's Roadshow. /ubbthreads/images/graemlins/blush.gif
 

Zelandeth

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Re: Old, Old panel meters, discovered in a box tod

Polishing? Not a chance. I did however use a soft cloth to remove the (live, and very busy I might add) cobwebs they were encrusted in, and sorry, no way were they coming in here along with the spiders, I have enough of them in here as it is. Other than that, they appear exactly as I unearthed them.

No metal surfaces, the casing of all the meters appears to be bakelite. Afraid that none of them (to the best of my knowledge) are illuminated. The bottom of the kV meter's case seems to have faded, guess it's spent some considerable amount of time sitting in the sun at some point.

Not actually planning on feeding anything power (aside from the one meter - which I actually have a use for), especially the runtime meter - for the very reason that is hasn't seen use in a long, long time (at least 20 years - which is roughly how long it's been in the box). The last thing I want to do is fry it. Anyway, even if I could find a 230-120V transformer, the frequency would still be off, and I have no idea what that would do to a syncronous motor.

Draco: I may be considering selling some/all of them, not sure yet. It's the sort of thing which I'd tend to hold on to forever and a day - despite not actually having a use for them (like I haven't got a big enough hoard of semi-useless junk in here already!), but on the same note, I could really do with the space and the money.

As for the 50Hz statement on the otherwise named DC meter, my guess would be that it was used for measuring unfiltered DC directly after rectification from an AC source - so it'd be seeing DC pulses at the supply frequency rather than a steady voltage. So the frequency could affect the reading in a mechanical meter I guess - note, I guess. So they'd state the frequency on the meter.

Should take them on AR...good plan, aside from being stuck in Aberdeenshire. Doesn't seem to be much interest in that type of thing up here.

Jack_Crow: Afraid that I know very little about radio systems, so can't tell you why the systems used differnece impedances. Only indication on the meters to do with impedences is Res <0.7?, though the word res there tends to make me think it's somehow referring to the resolution of the meter rather than anything to do with the system it's to be connected to.

Thanks for the feedback everyone.
 

DarkLight

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Re: Old, Old panel meters, discovered in a box tod

[ QUOTE ]
Mags_despiser said:
[ QUOTE ]
DarkLight said:
[ QUOTE ]
Mags_despiser said:
Wow wouldnt these be considered antiques? If you can find the maker of all of these meters, then they might go for some. Or if you plan on keeping them for show, you can polish em!

[/ QUOTE ]


Generally NEVER EVER change the finish on an antique item unless you want to make it worth instantly half or less of what it was.

[/ QUOTE ]
Sorry, I dont know anything about antiques.... /ubbthreads/images/graemlins/frown.gif

[/ QUOTE ]

to a 12 year old an antique is what he got for christmas last year! /ubbthreads/images/graemlins/wink.gif
 

MaxaBaker

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Re: Old, Old panel meters, discovered in a box tod

Hey, that's a little harsh DarkLight /ubbthreads/images/graemlins/rolleyes.gif /ubbthreads/images/graemlins/tongue.gif



Then again, everybody is stereotypical sometimes /ubbthreads/images/graemlins/blush.gif
 

KC2IXE

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Re: Old, Old panel meters, discovered in a box tod

Jack,
Missed that the RF power meter was a thermocouple type, as I had never heard of them - I know what type K is - remember, I used to run the environmental lab at one of the LI contractors - we mostly used type T /ubbthreads/images/graemlins/smile.gif

Used a twanger meter everyday, but ours was for 400Hz - it was on our Motor Generator. Here we were, a company that made kick butt milspec AC power supplies including 60Hz-400Hz inverters, but what supplied the 400Hz in our shop? A 30+ year old Genset!! Why? Because they could take a heck of a lot MORE abuse than the solid state stuff

Heck, I think I did OK noticing the broadarrow at 5:45am while getting dressed for work
 
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