Static on right channel

Timbehh · 5158

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Offline Timbehh

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on: August 19, 2012, 03:12:00 AM
I finally got my Crack + Speedball on working condition again (had problems after Speedball, one resistor was in short), but now i have static noise on right channel. It



Offline Grainger49

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Reply #1 on: August 19, 2012, 03:16:13 AM
Tim,

Start simple.

Did you have static before the Speedball?  Does the static level change with the volume control?  Is it constant or only once a minute?

Try reseating the tubes several times.  Remove it, put it back in and repeat 5 or 6 times.  This cleans the tube pins and the socket at the same time.

Even new tubes and new tube sockets can get a little corrosion on the metal parts before being put into service.



Offline Timbehh

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Reply #2 on: August 19, 2012, 08:58:04 AM
Tim,

Start simple.

Did you have static before the Speedball?  Does the static level change with the volume control?  Is it constant or only once a minute?

Try reseating the tubes several times.  Remove it, put it back in and repeat 5 or 6 times.  This cleans the tube pins and the socket at the same time.

Even new tubes and new tube sockets can get a little corrosion on the metal parts before being put into service.

I didn



Offline Natural Sound

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Reply #3 on: August 21, 2012, 10:00:56 AM
Tim,

Start simple.

Did you have static before the Speedball?  Does the static level change with the volume control?  Is it constant or only once a minute?

Try reseating the tubes several times.  Remove it, put it back in and repeat 5 or 6 times.  This cleans the tube pins and the socket at the same time.

Even new tubes and new tube sockets can get a little corrosion on the metal parts before being put into service.

I didn



Offline Timbehh

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Reply #4 on: September 30, 2012, 05:22:35 AM
It
« Last Edit: September 30, 2012, 05:44:36 AM by Timbehh »



Offline Paul Birkeland

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Reply #5 on: September 30, 2012, 06:28:47 AM
Hello Timbehh,

When you lift the plug out slightly, you short the right channel to ground, so the hum and the signal will dissappear (in other words, the jack is operating properly).

Describe the resistor issue with the Speedball upgrade in more detail, that might provide some insight into the issue.

-PB 


Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Timbehh

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Reply #6 on: September 30, 2012, 08:42:06 AM
After the Speedball upgrade there was one resistor short circuited, and after fixing that, the amp started to work again. No other issues so far with resistors. Only the hum remains, and when the plug is bottomed, one channel disappears  :-[



Offline Paul Birkeland

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Reply #7 on: September 30, 2012, 09:32:59 AM
Which resistor was short circuited?

When you say "when the plug is bottomed", does that mean when the headphone plug is inserted all the way into the jack?

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Timbehh

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Reply #8 on: September 30, 2012, 11:10:50 PM
One of the metal ones, with 3 legs  :)

And yes, when it



Offline Paul Birkeland

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Reply #9 on: October 01, 2012, 05:15:05 AM
Ah, OK, so there was an issue with a transistor.  Can you also post the voltages? 

Was the damaged transistor the 2N2907 or 2N2222?

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline Grainger49

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Reply #10 on: October 01, 2012, 08:53:46 AM
Somewhere we need a sticky that says not to put the transistor body against the PCB.  I'm chicken!  I always leave tall leads since those PN junctions seem so susceptible to heat.



Offline Timbehh

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Reply #11 on: November 06, 2012, 05:23:02 AM
I finally had time to do something with my crack. The good news: the static is gone, totally. I replaced the 12AU7 with Philips ECC82 and no more static. But one problem still exists: even with the old tube, i get this loud "snap"- sound in LEFT channel when the device warms up (the static was in right), and after that the left channel is gone. When the device cools, the left comes back again. Seems like heat issue, but where should i start to look?

And thanks in advance, again



Offline Timbehh

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Reply #12 on: November 11, 2012, 05:26:18 AM
I suppose it was just tube settling in, i