Bottlehead Forum
Bottlehead Kits => Kaiju Stereo 300B amp => Topic started by: BenjaminSmith on April 22, 2022, 12:43:13 PM
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Issue: 0.0 OA voltage, D side. 530V on IA. No B side LEDs lit. Zero voltage on 46U. Kreg 0.08V A side, 0.9V B side. Amp has passed all previous tests. Help, please!
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I would reflow all the joints on that PC board other than the ones where LEDs attach.
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Paul,
All joints checked and reflowed. Still dead. I neglected to mention that I had initially connected the 26U black wire to +reg instead of -reg (now corrected), possibly leading to the vaporized LEDS.
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I did not notice the vaporized LEDs. You'll want to replace that entire C4S board with a fresh one.
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Probably because I neglected to post this pic :-[
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The new board arrived, went together and was installed. It works perfectly. Now the issue is with the A side board which was just fine previously. IA measures 530V per manual. OA also reads 530V, not 300V. Terminal 32U was measured as it did before the D side board went in, adjusted and stable at 175V. The LEDS on A side of A socket board do not light (the B side light as they should) whereas on the opposite D side all four light appropriately.
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A board that works and suddenly doesn't work will generally do so from flaky solder joints.
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Issue resolved. Red wire from D4 to OA was busted directly underneath board. I've had trouble with solid core wires breaking after repeated movement - I may be scoring the wire as I strip the insulation.
Anyways, thank you Paul. I should be listening to sweet music in an hour or so!