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6V6 test points


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thought I wrote this down but I can't seem to find it.


test wall for AC write that down.


I'm testing with the bulb on.. it's 40 watts and glows a bit after it's died down from the initial flash.

I believe I've heard some say it will do that and it's not indicitive of any special problem. very dim.


2 min. warm up.


starting with black probe to ground, red to test points.


R10 B+..

R10 B1..

R12 same as R10 B+..

R12 B2..


I have been measuring R3 off both sides but it's supposed to be the B3 side only, I guess.


then on to the 12ax7

pin 1

pin 3


then I test heaters.. and this is what I keep forgetting with these builds.. sorry! this will be printed out and

tacked to the wall so.. last time I ask.

(if it wasn't days or longer between doing this I'd probably remember.)


where are the test points for heaters?

I know I was doing this wrong so.. no sense trying to put that up again!


pin 6 should be same/close to pin 1

pin 8 should read as pin 3



pin 3


pin 5 for heaters again.. and how do I do that? For the life of me I can't remember what points to measure between.

I know where one probe goes.. not the other!



pin 7 B1 should drop from other reading


normally I'd read pin 9, skipping pin 8, so I assume I do pin 8 here instead.


It's an auto ranging meter so it comes out mV or Vac by itself.


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I have notes I took from pages similar to that.. and have the pages in my favorites as well.

I think you're assuming I can tell what I'm doing by reading this.. but it really doesn't answer the questions.


That is. I can look at it all day and still not know where to test the heaters.

I guess I'll just go stick the probes on and see what my notes tell me.



It would have been nice, all along, to learn proper names of parts throughout, while learning the paint by numbers stuff.. but the fact is,

most often technical data being beyond my experience, I often had to rely on diagrams and instructions.. consequently the tech stuff

still makes me go huh.. no committment to memory there.


What I was just telling myself is that I should go through all this material.. and correlate it between the 'put this wire over there' and

'filamabub your votamafy before you connectimate the phd'.


In short, wall charts. and then a habit of describing to myself what I'm doing using the technical jargon so that it sinks in. rather than relying on

lincoln logs.


But that's a hassle, too.. because sometimes a person, namely Twang, has about ten questions at any given point.

Which results in guesswork.


All you have to do is think about it. Anyone starting this with no real basic electronics tends to pass over the technical detail.. and it's generally

passed over by those telling you.

That is, you've probably said perfectly sensible things to me in addition to 'solder it in', but solder it in is what sticks.


Not a complaint. Just saying it don't fall into my head even with that funnel I stuck in it.


And again, I've got to develop that habit as I go along. To not do something without describing it, be the teacher so to speak.


and I will. As soon as I figure out where the heck I put all my folders.

Probably under the snowblower, it doesn't work either.

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same old same old.

readings come out the same as before I went all through the tests.



r12.... 244


r3... 229


pin 1 159

pin 3 .9

pin 6 no pop 150

pin 8... 1


pin 3 ...236

pin 4....237

pin 5.. buzzes like mad.. 5.1

pin 7 .. .5

pin 8... 12


and have run out of things to test or check.

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Aw come on Twang! I know you're already familiar with the names of the players you know you need to get your voltages from... The "Plate" aka "Anode" (a), the "Control Grid (g1), the "Screen Grid" (g2), the "Cathode" (k), and the "Heater Filaments" (f).


I'd a thought it would be kind of obvious. I mean, if you look at the tube connection diagrams on those tube data sheets, they show the socket pins numbered with the letters right beside 'em. They also shows you the standard electronic symbol for what each pin is connected to inside the tube. I've gotten used to seeing the internal tube symbols on schematics, but I still rely on the tube data sheets for the socket pin connections and voltages, etc.



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they all test to ground. except the heaters.. or something. I have no clue there.


if sewatt was up I'd just go reread the thread.


but there's still something very wrong here. those voltages don't make sense and everything checks out otherwise.

why no pop on pin 6?

I seem to remember you saying the buzz I heard on the 6V6 was normal.


before, I could at least get a sound out of a build.. but nothing from this one.. not a peep even if you crank it up.


I don't have any problem figuring out what voltages I ought to have.. I just don't know why I'm getting what I'm getting.

this should fire right up and work.


ah well. another for the junk pile.

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