Connect with us

Help identifying valves

Discussion in 'General Electronics Discussion' started by Mongrel Shark, Jul 22, 2013.

Scroll to continue with content
  1. Mongrel Shark

    Mongrel Shark

    260
    18
    Jun 6, 2012
    So I have been asked to help clean out my deceased uncles shed. He was a bit of a radio genius, worked most of his life running transmitters for various TV and Radio stations. Among many treasures discovered in the shed. Which I will try to get pics of for those that may be interested. I have found a few boxes of valves. I know nothing about them, but I figure they are probably worth something to someone. The family is pretty short for cash, so if I can help them sell these valves for a fair price I would be very happy. If there are a few I can learn to use for Tesla Coils, that would be cool too. A couple of them look pretty serious. 8 inch long, 3-4 inch diameter. I have seen similar ones used for Tesla coils. Not sure if the ones I have found are any good though. My Uncle was a master of valves, many people used to seek his help with them. There is a room full of test kit I haven't had a chance to look through properly yet, but one device looks suspiciously like a valve tester. I don't have a pic yet, but can get one when I go back there tomorrow. I am only in town one more day, so not sure how much I can go through. As far as helping the family with cash, there are a number of antique radios, amps, and telephones that should get a few dollars on ebay (Unless some could suggest a better site). I think I will put all the valve stuff together for another visit. Somewhere near any test stuff there.

    My main question for now, is what sort of kit would I be looking for to test the valves? Also if they have blackened glass inside, are they stuffed? I don't think he would keep broken ones, Although dad (uncles younger brother) suggested my uncle would keep damaged ones, that no longer had their original value, but still worked for other things. He was a master of re-using stuff, to say the least, it would take some time to describe some of the mods he made to some stuff, to be able to "borrow" circuits from them, for other things, via banana plugs and toggle switches installed into cases. For example I found a 4 channel mixer for an 8 track (and the 4 channel 8 track to go with it :)) that has extra 3 pin mic ports labeled 100v, 70v, 4 ohm and 8 ohm, I'm thinking its a speaker tester or mic tester? Although its anyone's guess? I know he also did something similar to an old o'scope, to "borrow" some HV from the crt... We are talking about someone that has been making radio transmitters since he was 12 years old, As well as getting most of his test kit, broken, out of bins, and fixing it when others couldn't, then went on to have a 30 year carer in radio transmission. So sometimes he could use stuff that was rubbish to most. Would damaged valves be one of those things? Should I keep damaged ones for myself or try to sell? One of the big ones, in a mile of tissue paper, is labeled 3000 amps.... Could be good for a Tesla driver?

    So I know this is all really vague, and my pics today are a bit limited. I need help though. There is several ute (pickup truck) loads of likely valuable stuff to go through... Some I can id ok, and test to see if working, and decide if fixable or parts if not working. Other stuff, like a bunch of old telecom kit from the 70's, and some radio boards from a cabinet rig, loaded with juicy Germanium stuff, has already made it into my salvage box. If anyone has any suggestions of what else to look out for, that could be good. Its the valves that are really worrying me. I'm not in this for parts for me, mostly want to help the family sort it all out. If I get a few germanium bits and maybe a scope, curve tracer, or freq analyse. I will be happy. Also eyeing off a few old Analog Multimeters, but will probably teach my Uncles sons to use the simpler test kit, as they where too young to learn from their dad before he passed on. I was the only family member to pick up any electronics from him. 20 years ago, when I was 10... He taught me to use an analog meter, so I'd like to pass that on to his boys :) Think I'd rather make my own analog meter anyway....

    There is also stuff like this homemade computer. Which appears to send text via UHF radio....
    [​IMG]

    Notice the lack of outputs... UHF unit seems to be the only out, looks like a small single transistor amp on the output? No monitor or anything..
    [​IMG]


    Anyway, I think you all should have some idea of the crazy inventions now.. Here is a pic of one box of mid size valves. There are more boxes of smaller ones, and a few really big ones.
    [​IMG]

    Other stuff that needs to find a home, include a large dummy load. 500w 98-108mc (mhz)...
    [​IMG]

    [​IMG]


    So anyone got any ideas?

    I will try to get pics of what I can tomorrow, even if its just so we can all have a bit of a drool :D
     

    Attached Files:

  2. davenn

    davenn Moderator

    13,765
    1,920
    Sep 5, 2009
    thats actually VHF channel 1 cant quite read the numbers on the main CPU but it looks like a Z80 based unit


    That last 2 pics .... well labelled in the second last pic a nice RF dummy load complete with power and freq ratings :)

    if you want to identify the valves just type their numbers into google eg 12AU7, 6AX4 etc etc
    there are still valve testers around, they are getting very old now. A mate had one at a amateur radio club meeting a month ago and was testing a few tubes .... the testers are a tricky beast to get the hang of using.... maybe you have an old amateor operator in your area that has a working tester that he could test the tubes for you?

    Dave
     
    Last edited: Jul 22, 2013
  3. KrisBlueNZ

    KrisBlueNZ Sadly passed away in 2015

    8,393
    1,270
    Nov 28, 2011
    The "UHF unit" could be a modulator for connection to a TV, to act as a monitor.
     
  4. shrtrnd

    shrtrnd

    3,796
    503
    Jan 15, 2010
    My opinion is you might be able to get some money for the dummy load. Put an ad
    in the classified section of some amateur radio bulletin boards.
    The valves are used, and they'd need to be tested before installing them in anything.
    You might be able to make a small amount of money from a ham radio club if you
    sold the lot of them in bulk. The club members would probably have somebody that
    could come-up with a tube-tester to salvage anything they might be able to use.
    (But don't plan on making much money from that).
    Good luck on your salvage project.
     
  5. duke37

    duke37

    5,364
    769
    Jan 9, 2011
    Some old triode valves are worth a lot of money, also big transmitter/audio valves.

    Sort the valves by their bases and whether they are glass or metal.

    If the type number is not clear, do not scrub the valve to clean it. The number will disappear forever. Valve testing is only an approximate science and you may be better selling untested rather than guaranteeing perfomance.
     
  6. shrtrnd

    shrtrnd

    3,796
    503
    Jan 15, 2010
    Let me know who's paying the big bucks for those used, untested tubes, I can get rich
    pretty quick scrounging the recycle places here.
     
  7. duke37

    duke37

    5,364
    769
    Jan 9, 2011
    I have no idea where your recycling centres are. Common valves are not worth much.
    TV valves are ten a penny except PL509 which can be used for high power audio or RF amplifiers. I understand UL42s are getting rare and B9A double triodes are used by audio amplifier builders.

    My brother found a Mullard DO42 triode. I was contacted by someone who had one and would like another but said that he would not be able to afford it. A friend found a pair of PX4s in an antigue shop, these were sold on e-bay for a substantioal amount.

    I have a couple of Mullard TY4-500s, I doubt if I will get around to making a transmitter to use them so they may be sold.
     
  8. shrtrnd

    shrtrnd

    3,796
    503
    Jan 15, 2010
    I've got a lot of NOS (new old stock) valves left over my TV/Radio repair days.
    (Mostly US tube numbers). I know the new valves you mentioned are very pricey now.
    I had a lot of used valves I tried to unload over the years, and nobody wanted them.
    The Russians kept their valve factories up and running and now dominate the amplifier
    market here, filling-in the requirement for audiophiles. There aren't that many people who
    need valves anymore, mostly audiophiles and antique radio restoration places. But I
    don't know anyone here who's interested in used valves. I think the people who want
    valves now, have the money to buy new ones.
    Yeah, some of the old amplifiers you mentioned (new) run $60-80 or more.
    Anyway, I didn't think Mongrel Shark should expect a big windfall from used, untested, valves. Tube testers don't always tell you if a valve is bad, but I've never
    had one tell me a valve was bad, that wasn't. So if nothing else, with a tube tester,
    you can find out for sure what's not worth saving.
     
  9. davenn

    davenn Moderator

    13,765
    1,920
    Sep 5, 2009
    again ... its a VHF modulator..... yes thats exactly what it is used for :)

    Dave
     
  10. Mongrel Shark

    Mongrel Shark

    260
    18
    Jun 6, 2012
    Some of the bigger valves have Tested, and some percentages marked on the box. Cant remember exact details, but one had 85% and 70%, seemed to depend on how it would be used. That one also had 3000 amp marked on it. Thinking it could be good for Tesla driver :D
    I know Tesla drivers pretty well, so good for me to learn..

    I would look them up by number, but many have numbers rubbed off.

    I have Google image searched Valve tester, not what I was looking at yesterday, which could be a freq counter of some kind, had one scale with 0-100% the other had numbers I couldn't make sense of, but a large hole that looked like a valve may go in. I'll get more pics today.

    Anything else I should be look for that may help my Uncles wife pay the bills? Most of his life he was chief engineer at large transmitting stations. I'd prefer to know what I'm doing with a valve tester before I sell the valves. Would really old tube radios and amps be worth listing on ebay or a radio club message board? Also really old Telecom (Australia) test kit caught my eye. Would be from early 80's, probably replaced with something newer for my uncle to have it. A bit hopefull I might get some germanium stuff in the phone stuff. There is also a few boxes of really old Phones, with analog dialers. Really old ones.
     
  11. davenn

    davenn Moderator

    13,765
    1,920
    Sep 5, 2009
    the tubes are not really worth anything
    I had a huge tube collection before I left New Zealand in excess of 7000
    they were all given away to whoever wanted them

    some old test gear may be of some value to collectors

    Dave
     
  12. shrtrnd

    shrtrnd

    3,796
    503
    Jan 15, 2010
    Mongrel Shark, it seems like the guy kept everything, whether it was working or not.
    There are probably quite a few things there that have value, but it'll be a matter of
    Googleing what you find, to try to see what has value and what doesn't (other similiar
    items that other people are trying to sell).
    From the pictures you posted, a lot of the items will have no real value.
    When you find something like that dummy load, Google the model number and see
    what other people are asking for similar types.
    Sorry, but if you don't have some really useful equipment in the lot, his widow is
    going to be financially disappointed.
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-