OK..I'm stumped..Startup

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jjman
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Re: OK..I'm stumped..Startup

Post by jjman »

So pin 2 measures 3.x VAC to ground. And pin 7 (not 5) measures 3.x VAC to ground. And, at the same time, pin 2 to pin 7 measures 3.x VAC.

Is that tube's heater definately on? (Only one OP tube is needed for sound.) How about on the other OP tube?

If all the tubes have only 3.x VAC on their heaters maybe there is an overload on the heater circuit? Although I would expect the fuse to blow under such a severe overload.
If it says "Vintage" on it, -it isn't.
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Richie
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Re: OK..I'm stumped..Startup

Post by Richie »

My screen voltage at pin 4 of V5 is -32.56
is this a writing error? pin 4 of V5 should have a high B+ voltage.
Pin 5 of V4 or V5 would have the neg bias voltage.
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stevek66
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Re: OK..I'm stumped..Startup

Post by stevek66 »

Richie wrote:
My screen voltage at pin 4 of V5 is -32.56
is this a writing error? pin 4 of V5 should have a high B+ voltage.
Pin 5 of V4 or V5 would have the neg bias voltage.
Sorry typo on my part.
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stevek66
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Re: OK..I'm stumped..Startup

Post by stevek66 »

Well,
I'd like to thank everyone here for the help.
It's all good,Sounds good,great actually.
I don't have anything besides clips to compare it to.
I will play around with preamp tubes alittle more but a
RFT in V1,Brimar in V2 and a JJ in V3 sound pretty damn good.
I have a pair of Winged C's in it now but I'm gonna throw in a pair of NOS Teslas to see how they sound.

Thanks again
Steve
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Ron Worley
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Re: OK..I'm stumped..Startup

Post by Ron Worley »

Sounds like you're up and going. If you were measuring heater to ground, then 3.x V is right... it's going to be about 6.3 across both heater pins on a given tube...

Ron
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skyboltone
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Re: OK..I'm stumped..Startup

Post by skyboltone »

I gotta add here Steve; you need to see 6.3 across 2/7 on the power tubes and 4,5/9 on the little tubes. If you don't you've got a filament to cathode short in one of the tubes somewhere. It just can't be any other way. Keep lookin. Check the PI where the two cathodes are tied together. Something is goofy.

Dan
The Last of the World's Great Human Beings
Seek immediate medical attention if you suddenly go either deaf or blind.
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stevek66
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Re: OK..I'm stumped..Startup

Post by stevek66 »

skyboltone wrote:I gotta add here Steve; you need to see 6.3 across 2/7 on the power tubes and 4,5/9 on the little tubes. If you don't you've got a filament to cathode short in one of the tubes somewhere. It just can't be any other way. Keep lookin. Check the PI where the two cathodes are tied together. Something is goofy.

Dan
Hey Dan,
It's all good....
Across 2 and 7 I'm getting 6,37 acv.
I have been trying it out with my Strat so far but this morning I plugged in my 56 Reissue,Wow.P90's sound pretty wicked.
I can't wait to take to rehearsal...

Thanks Steve
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