Bottlehead Forum
Bottlehead Kits => Kaiju Stereo 300B amp => Topic started by: hpleung on May 29, 2022, 03:45:26 PM
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Hi,
I am currently trying to do the driver testing.
IA = 482 volts
OA = 300 volts
However, 46U <--> Safety ground
Gives close to 0 voltages. Trying both sides and same results (i.e. 32U <--> Ground)
Any idea on where I should look? Feels to me like a missing connection.
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I see substantial damage to one of your filter caps and a blackened power supply resistor, is there a little more to the story?
Can you post some more photos, ideally of the top and bottom of the PC board and the 9 pin socket wiring? The output of the driver C4S will stay at 0V for a period of time before slowly ramping up, which is the intended operation of the soft-start circuitry.
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Hi,
Yes, I purchased this limited edition (the bronze color one) one out of Audiogon. It looks unused when I received it except for the capacitor dent as you mentioned. The "blackened" resistor is just a tape I stick on.
Attached the pictures requested.
I waited for 1 minute and the voltage still stayed at 0 volts.
Thanks.
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Well the kit is built with stranded wire, and you may have some little strand poking out that's touching something it shouldn't.
Why is there tape around a resistor? Can you return this kit to the seller?
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Hi,
I think the seller purchased the kit directly from Bottlehead and never used it. It looks legit when I received it with plastic around the parts. I don't think it was ever used.
I chose the stranded wire although the kit came with solid core wire. Perhaps a mistake on my part but I notice often the solid core wire would break.
From the pictures; are you able to tell if there are any obvious connection that is missing? I will go and inspect if there are any stranded wire sticking out.
Thanks.
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You're missing a transistor on the B side of the PC board.
Yes, stranded wire is not a good idea.
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Solid core wire breaks because it is being improperly stripped.
Watch the video starting at 8:45 to 12:10.
https://youtu.be/EN16Pi7pcfk
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Thank you both. The missing transistor was it. It works now.