• 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.

Help putting an old tube tester back into service

Hello,

Found a tube tester hidden away and covered with dust, its probably not been touched in 15 years or so when it was moved there and put away. I was really happy to find it because i have a lot of unknown tubes that id like to know if they are good or not.

Is there anything i should be careful of when trying to put it into service again? It seems to be pretty much just a network of switches, with a few resistors and a coupple of caps. Should i do anything more than test the caps and give the switches some electronics cleaner? Can i use it to find "matched sets" somehow?

Here is the model of tester i found: https://www.vintageradio.nl/Diversen/tech_tc2_tube_tester_engels.htm
The schematic is on that website, i am unsure if i could repost it here so ill just link the page.

edit
And what about testing tubes that are not in the manual? Like the 6DJ8/ECC88?

Thanks for any help 😀
 
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I'm sorry to say that this is one of the most no frills, bare bones tube testers that I have seen. Being a DC emission tester that probably makes a diode out of a tube by connecting the elements together to measure current flow through it. Low voltage emission tests cannot accurately be used to match tubes. You need at least a good dynamic tester that measures amplification factor for that. And this tester uses an auto transformer for it's power which can make it unsafe because there is no isolation from the main power line. But if you do want to use it, just clean the switches. The two capacitors are small and don't handle much high voltage.

As far as checking tubes not listed, you would have to wing-it. Meaning, picking a similar tube with the same pin-out and experiment with it. You would start with several new or "known to be good" tubes to adjust the initial settings as good, and then go from there. Or find an updated listing that probably doesn't exist. Good luck.
 
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