• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.


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i came across a box of tubes but i dont know anything about tubes. can someone tell me what tubes are worth money? highly sought after? there are several ge's ,phillips, tung-sol or something like that and others. they are in an old tv/radio repair case. and is there a way of looking at them and telling if they are bad? many have a crome like top----i think this may be normal, but some have silver on the side (does not look like its suposed to be there). then again i dont know ANYTHING about tube!! any input??? shannon
tubes found

If you read the numbers on either the box or on each tube itself, and post a list, I or someone else could tell you if you have an "gems". Some could be worth a lot of money. For instance: Tung Sol 6550 might get you $50-$75 each. GE 6550 a little less. If you have any Telefunken, Bugle Boy Amperex, Mullard, Western Electric. you could have the potential to get some major cash.
If you have a lot of GE RCA Sylvania Raytheon, depending on the tube numbers and condition, you could still have some valuable tubes, or they could be worth a couple bucks. Depends greatly on the specific tube.
Tubes Value

As far as major brands besides Western Electric most tube numbers that audio guys buy will start with a 6 or a 12. Tubes that start with a 7 for instance were probably made for TV and have little or no value. Most tubes from Europe that have audio applications begin with E. Any tubes that have a 4 digit number are worth something and most tubes that have JAN on the tube or box are worth something. The 4 digits are industrial strength versions and the JANs are made for the military. I don't know anything about transmitting or sweep tubes for HAM radio but those are worth some good money. There were probably close to 25,000 different tubes made but only a few hundred are really still used to any degree. It can get real complicated. If you have a carrying case made for tubes chances are that most of the tubes were for television because that is what most repairmen carried. There is definatly overlap but I bought a tube caddy that was 75% full and only 1 tube was worth over $50 and maybe 5% of the tubes were worth keeping for use. I gave over 1000 tubes away to a tube dealer so they wouldn't go in the trash after I went through the stock of an old repair shop. I kept maybe 50. I hope you have some real treasure, but only an audio hobbiest or HAM guy would have a caddy of sought after tubes. A TV repairman will have a few . The only way to know if a tube is good or not is to test it. Even new in the box can be bad. Used tubes are worth less no matter how well they test.
i had someone give me a hefty bag full of tubes that they had in their garage for a long time in a tube caddy. the roof leaked and ruined the caddy and alot of the tube boxes (they got wet and stank real bad) i poured em out on the floor and re-bagged em by brand first and then sometime later i found a tube database online and started to look them up one at a time. since i dont know alot about tubes i kept any that said "radio" audio" ect and put them in a seperate bag and i have about 40 of those now.i keep reading about tube audio equipment and am also reading the "navy basic electronics vol 1" book hoping that i can learn enough to safely buid my own equip. the guy also gave me a tube tester with the tubes and i also have 5 pieces of textronics test equip of wich i know little about other than the dual ps and the meter.

also ....never clean a tube with windex, it takes the lettering right off..:)
Don't assume that just becase a tube isn't labelled as an RF tube or something that it isn't useful. Many of the tubes in common usage today are described as something else in the manuals. The 6AS7, for instance, was designed as a pass tube for regulated power supplies, yet makes a splendid power triode for amplifiers.
It's all in how you hook it up.

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