[Captainclock]

Originally Posted by earlyfilm

Capt,

Both of those testers are emission testers. Watch your model numbers. The Heath TT-3 claimed to be a transconductance tester. I have never seen a schematic, so I cannot say for sure.

The TC-3 was the plain old Triplet circuit emission tester, despite the hype used in the advertisements in the latter years of Heath.

If you are only into pre-WWII radios, either would work and the Philco would be my choice. For any other use, the TC-3 would be better choice.

If you buy the TC-3, be sure to save the online manual that you found, as someone who claims to be the copyright owner, is actively trying to get all the online manuals removed.

Remember either tube tester will have to be rebuilt. Any capacitors in the circuit will have to be replaced and critical resistors checked for drift.

If you have a choice between an open top or one with a closable case, get the one in the case. The open top ones, collect dirt in the sockets and the switches and controls get ruined by accidental bumping in shipping and in storage.

For the record, my tube tester is the precursor to Knight 600, and was built in the 1950s. I have owned it since the mid-1960's, and it now has an updated tube chart. The circuit is electrically identical to the TC-3. (My Hickok 600 is still in line to be restored.)

James

I actually deal with both post war and pre-war type radios so that's kind of why I would like to have one of these tube testers, emission tester is what I kind of need since I'm mostly just checking tubes to make sure they're functional or not, since I'm not doing a whole lot of work with equipment that depends on whether or not tubes are matched properly or not. So I might go with the Heathkit since I can also check "modern" tubes in it as well.