Those can hurt if you aren't careful!
Pulling the coupling caps will also tell you if they are leaky. This is a very common problem.
Pulling the coupling caps will also tell you if they are leaky. This is a very common problem.
But, are you using them in matched pairs? I have my doubts. What tube tester are you using? Stark 9-66 or Hickok are members of a few that measure dynamic transconductance. Most of the others are emission testers and are next to useless. Okay, completely useless. They test the tube as a diode to see if the cathode can emit enough electrons, and that is all. A pointless test unless a tube fails. Then it is well and truly junk.
all tubes matched really close anatech, with my stark 9-66
when I was in the army we had our series of publications (CFTO's) for every piece of equipment, individual books that covered many topics, ie "tests and adjustments", "equipment description", "disposal instructions"
what I'm also looking for is a link to the "Theory of Operation" hopefully for a Williamson amplifier.
The CFTO detailing theory of operation of any piece of equipment starts, as an example;
When the power switch is engaged current flows through the fuse, the switch and the primary winding...
And it should include every minute detail on the full operation of the amp... does an instruction like this exist?
when I was in the army we had our series of publications (CFTO's) for every piece of equipment, individual books that covered many topics, ie "tests and adjustments", "equipment description", "disposal instructions"
what I'm also looking for is a link to the "Theory of Operation" hopefully for a Williamson amplifier.
The CFTO detailing theory of operation of any piece of equipment starts, as an example;
When the power switch is engaged current flows through the fuse, the switch and the primary winding...
And it should include every minute detail on the full operation of the amp... does an instruction like this exist?
Excellent link. I have it in print, but now it can be put on my tablet too! Perfect when waiting for someone.
Let's hope you don't have to follow "disposal instructions". I am familiar with those publications, and also the US version. Sometimes they include information civilians don't get. Interesting read if you have the time. I can't stand information shaved so finely and would want them to just get on with it.
I've used the transconductance readings to match tubes, but I'm not 100% sold that they are that good compared to specialized equipment. Still, it's the only thing I have and it seems to agree with other tubes bought matched.
When were you discharged? Just curious.
-Chris
Let's hope you don't have to follow "disposal instructions". I am familiar with those publications, and also the US version. Sometimes they include information civilians don't get. Interesting read if you have the time. I can't stand information shaved so finely and would want them to just get on with it.
I've used the transconductance readings to match tubes, but I'm not 100% sold that they are that good compared to specialized equipment. Still, it's the only thing I have and it seems to agree with other tubes bought matched.
When were you discharged? Just curious.
-Chris
Had a quick look at the link rayma thank you!!
at first glance it seems to be slightly more advanced than I was hoping for but will read it and see how much I can comprehend asap
Was looking for a dumbed down version of that I'm thinking
Anatech, joined 1986 released 2015, she was a pretty good go! 🙂
at first glance it seems to be slightly more advanced than I was hoping for but will read it and see how much I can comprehend asap
Was looking for a dumbed down version of that I'm thinking
Anatech, joined 1986 released 2015, she was a pretty good go! 🙂
Hi bolly,
You had a good run.
As for the reading material, try reading the more difficult parts more than once in shorter chunks. Try to visualise what they are trying to say. Keep in mind that repairing something and designing it are two completely different things. You might have to read, work a little trying any hints or ideas you had, then back to reading.
-Chris
You had a good run.
As for the reading material, try reading the more difficult parts more than once in shorter chunks. Try to visualise what they are trying to say. Keep in mind that repairing something and designing it are two completely different things. You might have to read, work a little trying any hints or ideas you had, then back to reading.
-Chris
If nobody has suggested it before, I will be the first:
Get an ARRL "Radio Amateur's Handbook", and read the Theory Sections
at the front of the book. They are available online at the ARRL site.
The new ones may not cover any or much tube theory, but you Do need the rest of the theory.
They are well written, and you will understand it.
In order to really cover tubes best, you should get a 1950s or 1960s
Copy (can sometimes be found at an Amateur Swap Meet).
At one job site, I made sure that all my co-workers had an old copy of the handbook.
After getting a crystal set in 1956, I took a trip to the local library,
and devoured the theory sections in a 1950s copy of the handbook.
Starting with that:
Electronics became not only a lifetime hobby, but gave me great jobs for 43 years.
I still occasionally use my copies of the handbook, when I am not sure I remember some particular fact correctly, and want to check on my memory.
Get an ARRL "Radio Amateur's Handbook", and read the Theory Sections
at the front of the book. They are available online at the ARRL site.
The new ones may not cover any or much tube theory, but you Do need the rest of the theory.
They are well written, and you will understand it.
In order to really cover tubes best, you should get a 1950s or 1960s
Copy (can sometimes be found at an Amateur Swap Meet).
At one job site, I made sure that all my co-workers had an old copy of the handbook.
After getting a crystal set in 1956, I took a trip to the local library,
and devoured the theory sections in a 1950s copy of the handbook.
Starting with that:
Electronics became not only a lifetime hobby, but gave me great jobs for 43 years.
I still occasionally use my copies of the handbook, when I am not sure I remember some particular fact correctly, and want to check on my memory.
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Hiss is a Fact of Life , so live with it.
Being inaudible with regular speakers so barely audible with high efficiency ones means it´s level is about what is to be expected.
Are you sure it´s internal or cause by the amp itself?
It might be very well be coming from outside.
Short amp input ... what happens?
What is the Music source you are using to drive it?
Here's something similar for free.
http://www.qsl.net/sp9hzx/img/The Beginner's Handbook of Amateur Radio.pdf
Thanks for the links and advice fellas! will definitely revisit this thread many times as I really do need to know what makes these babies tick 🙂
Jmfahey, and all, I have found the source of the noises!! One of my smoke glass kt66, even though it tested good, I noticed it rattled like a burnt out light bulb!! 🙁
I've got more of the same tube so a swap was convenient! Using smoke glass RCA vt-231, tfk 12au7 and fivre 5v4g, with my double crown chipped cd880 I can say everything is back to normal, about 99.9% noise and hiss free!!
Jmfahey, and all, I have found the source of the noises!! One of my smoke glass kt66, even though it tested good, I noticed it rattled like a burnt out light bulb!! 🙁
I've got more of the same tube so a swap was convenient! Using smoke glass RCA vt-231, tfk 12au7 and fivre 5v4g, with my double crown chipped cd880 I can say everything is back to normal, about 99.9% noise and hiss free!!
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