Bottlehead Forum

Bottlehead Kits => Kaiju Stereo 300B amp => Topic started by: ArtnShit on February 18, 2022, 07:52:07 AM

Title: Failed Voltage Test Page 47
Post by: ArtnShit on February 18, 2022, 07:52:07 AM: Hi,

One of my readings was off on the voltage test on page 47 of the manual. It was for 15U measuring around 530VDC. Both 10U and 14U were in the correct ranges. Any suggestions on troubleshooting?

Thanks!
Title: Re: Failed Voltage Test Page 47
Post by: Paul Birkeland on February 18, 2022, 02:19:05 PM: Can you post some photos of the power supply you have wired up?
Title: Re: Failed Voltage Test Page 47
Post by: ArtnShit on February 18, 2022, 04:58:48 PM: Hi Paul,

Here is my power supply.

Thanks!
Title: Re: Failed Voltage Test Page 47
Post by: Paul Birkeland on February 19, 2022, 04:50:51 AM: You have not shown the terminals where you are getting the odd voltages.
Title: Re: Failed Voltage Test Page 47
Post by: ArtnShit on February 19, 2022, 04:55:29 AM: Totally goofed that, my bad!
Title: Re: Failed Voltage Test Page 47
Post by: Paul Birkeland on February 19, 2022, 05:03:18 AM: When you attach a capacitor to a terminal strip, you need to pass the leads through the terminal strip, then bend them up so they rest against the terminal strip, then trim them. What I'm seeing there is that you have a lot of leads that have been cut super short and you are relying on just the solder joint to hold the capacitor in place. For your build, I would push the caps in a bit more so the leads poke through the terminal strips a little more.

What DC voltages do you get at 14, 17, and 18?
Title: Re: Failed Voltage Test Page 47
Post by: ArtnShit on February 19, 2022, 06:21:43 AM: Cool, I will work on getting a better contact with the caps then test that signal as well! Thanks.

As far as measurements right now - All w black probe on 1U.

10U- 264
14U- 534
15U- 530
17U- 525
18U- 518

Let me know what you think.

Thanks so much!
Title: Re: Failed Voltage Test Page 47
Post by: ArtnShit on February 19, 2022, 06:49:17 AM: Just resoldered and all of the voltages are in the correct range now! Thanks! Quick last question/concern I have - Is it problematic for little pokey wires from the L part of the strips to touch the underside of the caps that are mounted to the U parts of those same strips? Or are they insultated?

Thanks
Title: Re: Failed Voltage Test Page 47
Post by: Paul Birkeland on February 19, 2022, 06:54:30 AM: You'd have to show me a picture of what you're talking about.

Terminal 14 would be wired to the star ground and should be at 0V. If it's not, that connection is not functioning and needs to be investigated.
Title: Re: Failed Voltage Test Page 47
Post by: ArtnShit on February 19, 2022, 07:14:04 AM: Terminal 14U should be reading 0VDC? In the manual for test voltages, it says it should be +-20% of 490, no? Terminal 14 is not wired to the star based on the manual, the closest is 18 on that tag strip.

Here is a pic of what I mean regarding the caps and touching stuff beneath them.

Thanks!
Title: Re: Failed Voltage Test Page 47
Post by: Paul Birkeland on February 19, 2022, 07:28:29 AM: Sorry I mean to say 18 should be 0V.

The components touching the cap body are only a problem if they poke through the cap wrapper and the bottom plastic disc, which is unlikely.
Title: Re: Failed Voltage Test Page 47
Post by: ArtnShit on February 19, 2022, 07:29:10 AM: Just noticed the connection to the star-ground on 18L was not super secure, resoldered, and it reads 0VDC on 18U.

A new thing that happened, when I took a reading from 14U (black prong on 1U) there was a big spark pop, now 15U reads at 129, was reading before the pop at 213 or so. Did I short something?
Title: Re: Failed Voltage Test Page 47
Post by: Paul Birkeland on February 19, 2022, 07:34:30 AM: You may have blown the fuse.
Title: Re: Failed Voltage Test Page 47
Post by: ArtnShit on February 19, 2022, 07:36:15 AM: How would I go about checking and confirming that? Is that the one in the IEC box?
Title: Re: Failed Voltage Test Page 47
Post by: Paul Birkeland on February 19, 2022, 07:50:54 AM: You can remove the fuse and test it with the continuity beep setting on your meter.
Title: Re: Failed Voltage Test Page 47
Post by: ArtnShit on February 19, 2022, 08:02:53 AM: The fuse is ok! Any other ideas about the sparks or the drop in voltage? I can double-check again if that's the move, too.

Sorry about all the questions and thank you for talking me through this.
Title: Re: Failed Voltage Test Page 47
Post by: Paul Birkeland on February 19, 2022, 08:03:08 AM: Yes, double check the voltages.
Title: Re: Failed Voltage Test Page 47
Post by: ArtnShit on February 19, 2022, 08:12:11 AM: Double checked, everything is in the proper ranges now! Weird. Should I be concerned about that spark? I have a feeling I connected two metal things that weren't meant to touch, but everything is going fine now?

Thanks again for your help.
Title: Re: Failed Voltage Test Page 47
Post by: Paul Birkeland on February 19, 2022, 08:17:01 AM: If everything is OK now, I wouldn't be too worried about the spark. If your meter probes have a lot of exposed metal on the tips, you can wrap tape around all but the last tiny bit of metal to offer some additional protection.