Build Thread:PQD2

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Yes, I build mine with pcb grinders boards. but double check with your boards, i might have forgotten something..
 
figured it out ;-)

But I Have another question.
I've isolated the LM317. But the middle pin is still connected to the bottom plate witch makes contact with ground, is that right? Or shouldn't that be happening? If not, how should I handle the isolation than?

Also when testing with the tubes installed (they glow) I got around 265V before the drop resistor and 0v after the drop and the Drop resistor starts to smoke... Not entirely sure it was smoke from this resistor, but something smoked.

When I do a continue measure, it seems that ground and 12.6v (measure point on the V3 board) is connected, I don't see any solder bridges, what could this be?
Hope you can help me out.
 
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To be sure I rebought another set of bridge diodes, another LM317 with heatsink (because its shorting to the case even with iso pad)
Also ordered other tubes, I have the EC88 while it should be ECC88 .....!
Hope it will be solved with this all.
If anyone have other ideas, please shoot!
 
Can anyone share where they found 6.8uf 400v WIMA caps for C59 and C60? What are the best kinds of caps for these? The PCB lists 4.7-10uf? The BOM shared a few posts back lists 400v, is that high of voltage really necessary?
 
Ahh, of course! Or a nylon screw would also be possible I guess.
Ground and 12.6v shouldn't be connecting right? (it's too obvious, but still..)
 
Its working!!!
The power board at least, still waiting on the transformers...

To be curtain I changed the two bridge diodes, and the LM317.
Put in the correct tubes.... ! (mis read the first time)
Had to paralel the resistor, to get a nice 230v.
Tapped power from the 12.6v with a transistor for the power on/off LED

I hope this heat sink is enough. Or is this a no go?
 

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Finally received the transformers.
left channel works great, right channel doesn't work, There seems to be output but I have to set the levels (after the pq2) very high
Any hints of were to look for the problem?
It doesn't seem to be the in/output xls connections or the connections to the filter board (I think).


Ok, I just swapped the tubes, and now the other channel is working.
so it's probably the tube..
I guess I should just order an other one right?
If there's something else I should check or do, please let me know ;-)
 
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just swapped the tubes, and now the other channel is working.
so it's probably the tube..
I guess I should just order an other one right?
If there's something else I should check or do, please let me know ;-)
That sounds pretty straightforward. Sometimes you just end up with a bad tube. It seems to me that you've found the problem.
 

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