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    Building, troubleshooting and testing of these amplifiers should only be
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Help Matching RCA 5692 Tubes

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"Matching" is a word often used as if it has an agreed upon meaning, which ain't really so. Match what, and at what conditions?

With the mighty TV2, you should be able to simply test the tubes at roll chart values, write the values on the glass, and be confident that nothing better could be done without much more detail about intended operation.

You'll have tested for a value called transconductance, which is as good a general thing to match for as any.

All good fortune,
Chris
 
If the test conditions and parameters are not clearly defined "matching" is a meaningless word. If you're selling on Ebay, NEVER states in your description that the tubes are "matched", whatever that means... or be prepared to refund the buyer up to 180 days after the sale if he decide to open a (SNAD) dispute because the tubes are not well matched according to HIS criteria (and HIS different test equipment or measuring procedures). And Ebay will invariably side with him...
 
+1 on what Tubologic says. Give Transconductance values from the TV-2 and if you can, test for current passed under test conditions. I don't know if the TV-2 can do this. With these 2 values, a knowledgeable buyer can make and informed decision whether the tubes are right for him or not. If somebody wants more info, tell them to buy somewhere else.

I've sold tubes off and on for around 15 years on Ebay, and I've seen it all...

Now for my rant... And this is NOT directed at anybody on this forum. Hopefully everyone here will get a laugh from this, but there is a lot of truth in it:

50%+ of tube sellers on Ebay are morons.
75% of tube buyers are even bigger morons, especially many in countries that think tube electronics are the "cool" thing to collect and show off to their equally posterior retentive, uptight friends.

I've sold old NOS carbon plate transmitting tubes that the buyer tested on his super duper Amplitrex tester, complaining that the tubes were "gassy". I told him to run them for 30 minutes so the plates can "eat" the gas and I never heard from him again but he did leave me positive feedback, so I guess he was ultimately happy.

I sold a pair of NOS 2A3s to some "engineer" in Colorado that wasn't happy with them so I had to refund him the money. There was nothing wrong with the tubes; the "engineer" didn't like the way the tubes looked in his amplifier, so he didn't want them. He came up with some BS that the tubes made weird noises in his amps. Fickle fickle fickle... I resold the tubes for more money and the second buyer was more than happy with them.
The point I'm making is: state the facts (test parameters) of your tubes. If people start asking all sorts of moronic questions about your tubes, they're going to be more trouble than what it's worth.
And remember... Ebay offers ABSOLUTELY NO protection to the seller, so sell to someone who knows what they're buying and you will have a smooth, hassle free transaction.

Daniel
 
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