B6 voltage too high on Paraglow II PSU update

kgwrocks · 74119

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Offline Paul Birkeland

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Reply #30 on: May 18, 2020, 03:06:15 PM
I mean, it won't really matter all that much to me one way or the other.  For the cathode bias resistors in the standard Paraglow, I have a ton of 2K/25W tubular resistors, and I use one of those and another 1.2K 10W resistor in series with that.

I also somewhat frequently just rebuild these on 8x10 chassis plates.   This gives me room for a really beefy 3K/50W tubular resistor that runs nice and cool. 

In either case, I do enjoy refurbishing the old kits. 

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline kgwrocks

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Reply #31 on: May 20, 2020, 12:26:36 PM
Hi Paul,
I got the smash kit in the mail today. I guess I will order the new giant resistors and the resistors for the smash kit.
I think I will try to get the amps working without the smash kit. If I get stuck on the smash kit installation, could I get the amps to you to do that part?
cheers,
Kevin



Offline Paul Birkeland

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Reply #32 on: May 20, 2020, 12:29:46 PM
Sure thing!

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline kgwrocks

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Reply #33 on: May 26, 2020, 02:42:33 PM
Hi Paul,
I'm going to order more parts soon. I am concerned about the power rating of the 3k0/50W in series with the 300r0/5W. Don't they both have to be 50W?
If now, does the order they go in matter? Which one should go to ground?



Offline Paul Birkeland

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Reply #34 on: May 26, 2020, 03:30:12 PM
Ohm's Law tells us that power is current squared time resistance.  Current is 0.060A.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline kgwrocks

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Reply #35 on: June 15, 2020, 01:24:45 PM
Update. I have updated the PSU on both Paraglow IIs. I also replaced the big resistors on the 2A3 tubes. B6 is still around 260VDC instead of 215VDC.

So I guess I will send or deliver the amps to you to do the smash upgrade and get the amps dialed in. I found the 5965 tubes that came with the kits. So I'll get those to you as well.

Please let me know the arrangements.

thanks,
Kevin



Offline Paul Birkeland

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Reply #36 on: June 15, 2020, 07:05:08 PM
Did you try rolling in a fresh pair of driver tubes?  I think those Tucker boards used the 6N1P right?  Those aren't exactly the longest lived tube in the world, and when they get flat, that plate voltage will start drifting up. 

Otherwise, you can just order the flat rate repair service for two amps, and that will take care of what you need done.  It may take a little while for the boxes to go out and come back to me, so toss a note in one of the boxes that's just a print out of this thread and I'll remember what to do. 

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man