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Vintage Test Gear and Workshop Equipment For discussions about vintage test gear and workshop equipment such as coil winders. |
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11th Nov 2018, 7:17 am | #1 |
Triode
Join Date: Feb 2009
Location: Ipswich Suffolk UK
Posts: 15
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Vintage Heathkit TC-2 Valve Tester
I have recently bought a 1959 Heathkit TC-2 valve tester for just under £30 to sort through my growing collection of (1000+) valves. I've bought it as a tool and not for restoration, so I'm not too concerned about modifying it.
I've not had a valve tester before, so this is a learning curve and I realise it's not going to be anywhere as good as an AVO or a Mullard etc. My question is for the more experienced amongst us, what mods could I do to make this piece of equipment more useful apart from adding a few more bases etc?
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11th Nov 2018, 11:20 am | #2 |
Nonode
Join Date: Jun 2007
Location: Coulsdon, London, UK.
Posts: 2,152
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Re: Vintage Heathkit TC-2 Valve Tester
I would replace the capacitor and rectifier, check the resistors and fit a 1 Amp fuse in the mains socket.
Then test it with a cheap valve to see if there are any problems. Bad contacts and faulty switches may then become apparent. It would be a good idea to create a calibration valve of known gm using a simple test circuit so that you could check the accuracy of the Heathkit. |
11th Nov 2018, 5:17 pm | #3 |
Heptode
Join Date: Oct 2008
Location: Aalborg, Denmark
Posts: 903
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Re: Vintage Heathkit TC-2 Valve Tester
I have a TC-1 and two TC-2 testers and in none of them have I needed to replace the rectifier. Since they use a copper-oxide rectifier it can't easily be replaced with a standard silicon rectifier diode (1N4007 etc.) because of different characteristics for the forward voltage drop. The rectifier is used btw only when doing the adjust-line calibration. Besides, I have yet to come by a defective copper-oxide rectifier at all; they last forever.
In all of the testers most resistors were quite off specifications and the 0.1uF capacitors for the leakage/short test function were themselves leaky. The TC-2 is an emission-tester that can't measure Gm but that isn't terribly important if you just need to sort valves in bad and (probably) good piles. When a TC-2 finds a valve Good it may still be faulty. You need a better tester for effectively finding valves with grid-1 current problems. A fairly inexpensive vintage B&K 667 (or 607) tester or the like will do it nicely. Last edited by tri-comp; 11th Nov 2018 at 5:24 pm. |
11th Nov 2018, 7:15 pm | #4 | ||
Triode
Join Date: Feb 2009
Location: Ipswich Suffolk UK
Posts: 15
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Quote:
Quote:
Some of the valves I have are vintage TV valves, ie PY500's, PL504' 509's etc and I want a reasonable chance of testing these as well.
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11th Nov 2018, 9:02 pm | #5 |
Moderator
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Location: Ipswich, Suffolk, IP4, UK.
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Re: Vintage Heathkit TC-2 Valve Tester
If you want to show that valves are good you're going to have to be able to test gm.
It would require extensive mods to this tester to do that. I suggest you buy or build a better tester.
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12th Nov 2018, 11:52 am | #6 |
Nonode
Join Date: Mar 2008
Location: Aberdeen, UK.
Posts: 2,839
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Re: Vintage Heathkit TC-2 Valve Tester
Hello jomac,
With over a 1000 valves to test, as Graham says, you'll eventually will need to think about a more advanced tester. One that can display Ia, whilst monitoring the correct -ve Vg. Particularly if your collection contains valuable valves such as ECC83's, EL &/or KT O/P valves, or very old PX valves, and so on. PM me your address & I'll send you a DC Standardised valve for testing your Heathkit tester, buck sheesh. But hey, you & Graham both live in Ipswich, so perhaps he could recommend someone local with an AVO VCM or similar, & who could possibly kindly also check how accurate/reliable your TC-2 is ? I ken sfa about TC-2's, but do they require test cards ? You might also need some alternative source of valve data, such as the vintage Bernards & Illiffe Valve Data Books(( see adjacent recent thread). Regards, David |
12th Nov 2018, 1:38 pm | #7 |
Nonode
Join Date: Aug 2010
Location: Resolfen, Wales; and Bristol, England
Posts: 2,588
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Re: Vintage Heathkit TC-2 Valve Tester
The Mullard is pretty much a go/no-go tester and needs a huge stash of cards to make it work.
The Heathkit isn't much better but at least it's switchable so you don't need the cards. An AVO will be overkill and will require a visit to the Bank Manager for a small mortgage to buy one. If you want better than the Heathkit, I can't recommend the Sussex highly enough, look on this forum for full details. There are quite a lot in existence now, and they have lots of functionality for not a lot of cost.
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13th Nov 2018, 12:32 am | #8 |
Triode
Join Date: Feb 2009
Location: Ipswich Suffolk UK
Posts: 15
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Re: Vintage Heathkit TC-2 Valve Tester
I have learned a lot from the comments guys, you have overloaded my brain with thinking, but I now realise that the best thing for the Heathkit is a renovation and sell on.
During this time, i haven't sat around, and kept looking for a solution to testing the valves I have, and maybe more in the future. During my travels, and some reading, I found this, not cheap, but claims to do most things. Would this be an interesting thing to consider? http://www.dos4ever.com/uTracer3/uTracer3_pag0.html
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13th Nov 2018, 7:46 am | #9 |
Nonode
Join Date: Aug 2010
Location: Resolfen, Wales; and Bristol, England
Posts: 2,588
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Re: Vintage Heathkit TC-2 Valve Tester
I have looked at that one, it seems well designed but it has too many features for my needs. I believe that the user interface needs a Windows computer which I don’t own. I use the Sussex at work to check and match valves for guitar amplifiers, I rarely need to do a full set of curves for a valve.
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13th Nov 2018, 11:27 am | #10 |
Nonode
Join Date: Mar 2008
Location: Aberdeen, UK.
Posts: 2,839
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Re: Vintage Heathkit TC-2 Valve Tester
Aye jomac, you say that that u Tracer is not "cheap", but what does it actually cost ? Certainly, if you envisage becoming involved with serious amplifier design or advanced valve circuitry, then you would need to study a valve's family of characteristic curves. I can't remember if anyone has put a price on a Tek, or Roetest, but I suspect that they cost as much as CT160's or VCM163's are now fetching(silly eBay prices of £1000 plus)!
If you just want to plod on with normal vintage radio pursuits, then an AVO VCM Mk1 or 2, or a Taylor 45 would suffice. You're still talking £150 to £300, depending on condition. I've heard that Mk's 3 & 4's are now being internet wheeled & dealed at £300 - £400 plus. If you've got the electronics skills, then the Sussex would be a worthwhile option. Hey - has anyone actually put a finished price on one ? Lets not forget the Hickok range of testers. American 110V yes, but highly thought of. Then myself & one or two other Forum folk have banged-on about building homebrew DC valve testers, but I shant go there. Regards, David |
13th Nov 2018, 12:13 pm | #11 | |
Triode
Join Date: Feb 2009
Location: Ipswich Suffolk UK
Posts: 15
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Re: Vintage Heathkit TC-2 Valve Tester
Quote:
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13th Nov 2018, 2:30 pm | #12 |
Nonode
Join Date: Mar 2008
Location: Aberdeen, UK.
Posts: 2,839
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Re: Vintage Heathkit TC-2 Valve Tester
Well jomac, I'm now in a quandary. On the one hand, I've had a fair bit of recent experience in testing early & very valuable 1920's valves for a BVWS chum who is into early vintage radio restoration. On the other hand - there is yourself who seems to intend just dealing valves as a business, as opposed to the ethos of this vintage radio repair & restoration forum.
So - I'm out of this thread. Comments Moderators ? Regards, David |
13th Nov 2018, 4:42 pm | #13 |
Triode
Join Date: Feb 2009
Location: Ipswich Suffolk UK
Posts: 15
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Re: Vintage Heathkit TC-2 Valve Tester
No, perhaps i misworded it David. I have a large collection of valves, many of them are either duplicates, or valves of no interest, it's these i intend to sell on, and fund's used to buy more for the collection, simple as that.!
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