Bottlehead Forum

Bottlehead Kits => Crack => Topic started by: Zniper on April 10, 2017, 04:14:40 AM

Title: Crack heat and noise [resolved]
Post by: Zniper on April 10, 2017, 04:14:40 AM: Hi everyone, I've got the amazing Crack + Speedball 1.1 for about two months. Everything works fine except the heat (on chassis) is pretty high. I'm sure that I couldn't leave my finger there for more than 2 seconds. I know the amp with tubes generate lot of heat, however not sure which would be the "normal" range?

Another small issue is kind of inconsistent background noise after running it for 3hrs continuously. The noise completely disappears after I turning off > waiting for ~20s > turning back on the Crack. Same phenomenon with different tubes, could it be the cold solder(s) or any possible causes?
Title: Re: Crack heat and noise
Post by: Paul Birkeland on April 10, 2017, 07:07:51 AM: If your voltages are correct then the amount of heat generated by the amp is OK.

The noise you're describing could be environmental, is your Crack near any wireless devices? It might not hurt to go over the hardware on the amp and be sure that all the screws are tight.
Title: Re: Crack heat and noise
Post by: Zniper on April 11, 2017, 12:36:18 AM: Yeah, all the voltages are in acceptable range.

There are indeed some wireless devices around but I did some tests of moving/disabling those but nothing change. Thing is noise will disappear after a quick reset, and the whole device are still warm/hot.
Title: Re: Crack heat and noise
Post by: Zniper on April 18, 2017, 02:08:54 AM: Hi there, now it has new issue. After normally running (with all LEDs light up) for few minutes:
- There is a loud pop on the headphone and the left channel goes muted
- One LED (at A3) doesn't light up.
- Resistances: Terminals 7, 8, B3, B6 (which should be 2.9K) read */1
- I'm using 220V AC input, the voltages are:
   1: 70
   2: 211
   3: 0
   4: 212
   5: 205
   6: 0
   7: 110
   8: 0
   9: 204
   10: 0

   OA: 210
   OB: 110
   G: 0
   B+: 205

I'm not sure if I need to replace that LED or resolder the connection points next. Any advice is greatly appreciated.
Title: Re: Crack heat and noise
Post by: Paul Birkeland on April 19, 2017, 01:39:19 PM: The LED at A3 doesn't look to be all the way soldered to A3. I would try reheating that joint first, then let us know what happens.

-PB
Title: Re: Crack heat and noise
Post by: Zniper on April 20, 2017, 04:13:03 AM: Quote from: Caucasian Blackplate on April 19, 2017, 01:39:19 PM
The LED at A3 doesn't look to be all the way soldered to A3. I would try reheating that joint first, then let us know what happens.

-PB
Thanks much for the advice, I think that's correct as after reheating A3 and few other suspicious ones, the Crack normally works. I'm still keeping an eye on this though.