[Scott F.]

I ran across a B&K 707 Dyna-quik mutual transconductance tube tester at my favorite flea market the other day. It appears to be in decent shape though the tag on it said it had been in storage and unused for over 30 years.

If anybody local is interested, they want $65 for it which isn't too bad. If you wanted, we could take and test a good tube (or few) on one of my good B&K 500's or my Knight, then take that same tube up there to see how it measured. That should tell you whether its in good working order. The 707 tests  9 pin mini's and octals but won't do 4 pin triodes. This one comes in a blue case and I'd rate the condition a 7 or 7 1/2 out of 10.

Heres a little lite reading on the B&K tester lines.
http://tone-lizard.com/B&K.html

Let me know if one of you local guys are interested and we can arrange to meet up there and give it a try.

Sorry to you out of town guys that might be interested but I'd rather not buy it, clean it and make sure it works properly then pack it up and ship it UPS. I'd have to add a chuck of change to the price in order to cover my time and costs, making it far less attractive for you.

[steve k]

Scott
I'm definitely interested. I skimmed the article, are there tubes in this thing?
steve

[Scott F.]

Scott
I'm definitely interested. I skimmed the article, are there tubes in this thing?
steve

Yep, it uses an 83 as a rectifier tube. You can buy NOS ones for about $10 if that one is worn. We can check it on my Knight to be sure. I think that guy said it used another tube too. Don't remember which one it was.

Oh, that tester does have the tube data sheets. I forgot to mention that. We should be able to find a repair manual online too.

[steve k]

Looks like it uses the 83 and a 6BN8. Sounds good, Scott. How far is it?
s.

[Scott F.]

Its just in Eureka.

[steve k]

Cool. I'll give you a call. Scott, do these testers usually need a lot of rebuild work, meaning, are there old caps and resistors that need to be replaced?
s.

[Scott F.]

On occasion. Hard telling though. Testing a tube or two should give us a good idea the condition its in. For the price, its worth checking out.

When it comes to replacing the caps, just don't let Mike D know about it, he's liable to load it up with Black Gates

[Mike D]

yup.  And if you put jensen bypass caps on those Black Gates, you tube tester with get faster readings.

If you don't buy the tester, I want it.  Please let me know if you pass on it.

Mike

[Scott F.]

Oh, I also forgot to mention that if you want to do away with the 83 rectifier tube I think AES or Duncan Amps sells the solid state replacement of the 83 for like $20. That will bring the machine up to operation (pretty much) immediately rather than waiting a minute or two for it to warm up.

Steve (and Mike), I'll run by this evening on the way home and make sure its still there. Steve, want me to give you a buzz while I'm there? I think they stay open until 6pm. Not sure if you can make it out by that time but I could run back to the house and grab and test a couple of tubes real quick then meet you there and we could try them on the B&K.