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OLD THREAD DAC End by Andrea Ciuffoli

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C

CustomHT

Member
Joined 2010
housing said:
CustomHT,

I don't have the regulator board, I have the HV shunt supply PCBs only.

Don't populate the 4 HV rectifiers and the 4 snubber capacitors on your board. Instead solder the center tap to a plate-thru' via connected to the -ve pole of C5 (100uF/450V) and the rectified HV to a plate-thru' via connected to the +ve pole of C5.

In such case, you can use the full 200mA capacity of the transformer.
Click to expand...
ok, I will try this.. What exactly is ment "to a plate-thru' via"?
Do I simply soldier the leads to the -ve and +ve pole's of C5 as suggested?
Cheers
 
R

regal

Member
Joined 2004
I read the Dac End 2 webpage, saw where he was experimenting with filters. If you are having trouble with no filter, one option is to increase the miller effect of the tube by adding a small cap from the grid to the plate, its capacitance is multiplied by mu and is a 2nd order low pass filter.
 
F

fredlock

Member
Joined 2008
housing said:
CustomHT,

I don't have the regulator board, I have the HV shunt supply PCBs only.

Don't populate the 4 HV rectifiers and the 4 snubber capacitors on your board. Instead solder the center tap to a plate-thru' via connected to the -ve pole of C5 (100uF/450V) and the rectified HV to a plate-thru' via connected to the +ve pole of C5.

In such case, you can use the full 200mA capacity of the transformer.
Click to expand...

CustomHT,

Don't get confuse. What housing meant was you already rectified the ac voltage outside the board and the rectified voltage which is DC is connected directly to the + and - leads of the C5.

I think Apelizzo is using the same transformer as we are, so why not try just the green and orange wire?
 

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V

vzs

Member
Joined 2005
Last edited:
C

CustomHT

Member
Joined 2010
fredlock said:
CustomHT,

Don't get confuse. What housing meant was you already rectified the ac voltage outside the board and the rectified voltage which is DC is connected directly to the + and - leads of the C5.

I think Apelizzo is using the same transformer as we are, so why not try just the green and orange wire?
Click to expand...

Ok that makes sence. Basically the board is made so I could have just used mains voltage connected straight to the 200-250V connection, but since I am using the output from the trannie I bypass the rectifier section..

I will try connecting the green and orange wire to the + and - wire of C5. And post results..
 
F

fredlock

Member
Joined 2008
CustomHT said:
Ok that makes sence. Basically the board is made so I could have just used mains voltage connected straight to the 200-250V connection, but since I am using the output from the trannie I bypass the rectifier section..

I will try connecting the green and orange wire to the + and - wire of C5. And post results..
Click to expand...

:eek: Don't connect the green and orange wire directly to C5. It needs to go thru a diode first for rectification and then connect it to C5. If you do this, then wear a safety glass first before you turn on. :D
 
Tea-Bag

Tea-Bag

Member
Joined 2006
Paid Member
I think I am over project'd right now and would like to sell my boards if someone is interested.
I have the 4 boards, plus the Analog 1865N-K chip from Mikel-Ann's GB. Additionally I have a few caps for the salas board to throw in.
I am looking for a decent offer on this. PM if interested.
 
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