I saw two tube testers at the antique mall one day...

[Captainclock]

Hello everyone a couple of weeks ago I went to one of my favorite antique malls and I saw in one of the booths 2 old tube testers that had the sockets for testing the old 4, 5 and 6 pin tubes besides the usual loctal and octal and noval and subminiature tube sockets as well, anyways one was a Philco branded tube tester from the 1950s and the other one was a Heathkit tube tester from the 1960s and anyways I don't know what model they were but they both looked like they were decent units and were complete.
My question is, which one should I go with if I were to get one?
I know very little about Philco or Heathkit tube testers and I would like to know if they would be worth my time getting them or if I should just pass on them and wait for a Hickock or B&K tube tester to come up.
Anyways the Philco they want $60 for and the Heathkit one they want $65 and I have no idea if those are reasonable asking prices or if I should talk the booth owner down on the price.

[Olorin67]

Try to get the model number on the Heathkit, some Heathkits were basic emissions testers (but still recommended if you cant afford a Hickok, easy to restore) and some were true Mutual Conductance testers similar to Hickok.
I found my Hickok in an antique store cheap, it was a bit beat up looking. They had a nice looking but basic emission tester next to it for 3 times the price...

[Captainclock]

Originally Posted by Olorin67

Try to get the model number on the Heathkit, some Heathkits were basic emissions testers (but still recommended if you cant afford a Hickok, easy to restore) and some were try Mutual Conductance testers similar to Hickok.
I found my Hickok in an antique store cheap, it was a bit beat up looking. They had a nice looking but basic emission tester next to it for 3 times the price...

I'll try and see if I can get over there again to see if I can get the model number off of them, they looked like they might of been basic emissions testers but I'm not sure as I don't even know what a Mutual Conductance tube tester looks like compared to an emissions tester.

[NoPegs]

Make sure the roll charts are present.

[Captainclock]

Originally Posted by NoPegs

Make sure the roll charts are present.

Well the philco tube tester had its roll chart intact, the Heathkit tube tester didn't seem to have a provision for a roll chart but it had a copy of its manual with it.

[Olorin67]

A mutual conductance tester will usually state so on the unit, it was a selling point. They tend to have a few more knobs than emissions testers. An emissions tester is entirely adequate if your checking used tubes to see if they have life lest. MC testers tend to be more sensitive to spotting grid issues that matter in some circuits. There were some proprietary circuits out there that were a bit in-between a true Gm test, and a plain emissions test, usually these were under some kind of trade name that included "conductance" in the title. Often these were a way around Hickock's patent.
pretty much no testers actually applied true working plate voltages to the higher power tube types, you still need to test them in a circuit as a final check.

[Captainclock]

Originally Posted by Olorin67

A mutual conductance tester will usually state so on the unit, it was a selling point. They tend to have a few more knobs than emissions testers. An emissions tester is entirely adequate if your checking used tubes to see if they have life lest. MC testers tend to be more sensitive to spotting grid issues that matter in some circuits. There were some proprietary circuits out there that were a bit in-between a true Gm test, and a plain emissions test, usually these were under some kind of trade name that included "conductance" in the title. Often these were a way around Hickock's patent.
pretty much no testers actually applied true working plate voltages to the higher power tube types, you still need to test them in a circuit as a final check.

OK so I went back to the antique mall today and looked at the tube testers and they both had roll charts on them, the Heathkit was a Model TC-3 or something like that, the Philco was a Model 050. I took a picture of them both, and they both appeared to be emissions testers but I'm not sure as they did seem to have quite a few more knobs and switches than the emissions testers that I already have did (the Sencore Mighty-Mite and the EMC 213 that I have of which both don't have provisions for the older 4-7 pin tubes like the ones I saw at the antique mall did.)

Maybe now that we have model numbers and some pictures maybe someone can tell me what they are and which one would be worth popping on.

EDIT: From what I gathered from the manual I saw online for the Heathkit TC-3 Tube tester it appears that the Heathkit might be a mutual Conductance tube tester because they mention a function that the tester is capable of called "Transconductance Testing" which I figure must be Heathkit's version of Mutual Conductance testing (since "Mutual Conductance" was a Registered trademark of Hickock and couldn't be used by Heathkit.)

[earlyfilm]

Originally Posted by Captainclock

From what I gathered from the manual I saw online for the Heathkit TC-3 Tube tester it appears that the Heathkit might be a mutual Conductance tube tester because they mention a function that the tester is capable of called "Transconductance Testing" which I figure must be Heathkit's version of Mutual Conductance testing (since "Mutual Conductance" was a Registered trademark of Hickock and couldn't be used by Heathkit.)

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

[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.

[Tubejunke]

Something I want to throw out there since I have dealt with it first hand is that Heathkit was in many cases exactly what the name suggests; a kit. A kit for the young student of electronics or whatever person may have been the recipient. What you end up with in a lot of cases are poor (very poor) soldering and/or mis-wiring. If you have the original build sheet you can go through one step by easy step and sort it out, but if not you can end up with a hair pulling mess. Not to mention that that Heathkit was never built for speed like say Hickok.

Now, I will also add that Heathkit offered the choice of kit or factory build. The latter of course being what you would want. I'm by no means bashing Heathkit. I recently took interest in their C-3 and other models of condenser "checkers" with the "magic eye" tube and found what I mentioned to be the case. The units were so utterly simple yet effective as all get out that I couldn't help but fall in love with the units. I could actually check caps at working voltages and visually watch for leakage current. Great stuff! I posted several in the classifieds here and sold a few with no complaints from the buyers who of course I informed of the exact unrestored condition of the units. The thread went dead pretty quick as they PMd me, but it's still there.

I don't exactly know how to tell the kit versions from the factory built versions except for visual inspection of wire dress, termination and soldering. I do have one that has a tag that says Heath Factory. I don't know if tube testers were big on the kit list or what. I know the offered about everything out "back in the day" in kit form.

With all this said, Philco would be the one for me simply because they were never kits and in my experience are almost always impeccable performers often with no restoration work. I've never seen or had a tube tester by them, but I have many radios and a 56 model TV set that performs like new with no restoration work other than the bullet proof chassis outliving the original CRT several years ago and I replaced that. I don't count that as real "restoration" though. More normal service like any other tube.

[Electronic M]

Only Philco tube tester I had was a dud, and I was too green to fix it back then.