Bottlehead Kits > Kaiju Stereo 300B amp
Issue with A Side C4S Board A [resolved]
giggsy:
Hi,
Have an issue with the voltage through 32U after attaching the board.
Let me preface by saying I accidentally broke the 215 1/8 watt resistor from A3 to the center socket pin when working on A4. I had a replacement resistor to hand but although the markings are the same, the size of the resistor is larger than the ones supplied (see pic) so it could simply be that i used the wrong resistor.
My issue is the voltage at 32U measures about 98V. By turning the potentiometer I can get it up to 100V.
On the D side 46U initially read 158V but was easily adjusted to 175V.
Here are some readings I took
A Side D Side
IA 508v 508v
OA 295v 296v
32U ~98v
46U 158v adjusted up to 175v
On A board
Kreg on A side = 6.88v
Kreg on B side = 6.75v
voltage across 4.99k Resistor = 2.47v
Paul Birkeland:
Turn the blue trim pot ten turns clockwise, then measure Kreg A. Now turn the trim pot ten turns counter-clockwise and remeasure the voltage on Kreg A. Let us know what those voltages are.
giggsy:
Turning 10x clockwise, kreg went down to 4.95v.
Turning back 10x counter-clockwise took the kreg back to 6.88v
Paul Birkeland:
Can you post a photo of the top of the board in question?
giggsy:
Thanks for helping Paul.
I've attached some pics of the board.
Navigation
[0] Message Index
[#] Next page
Go to full version