Speedball Upgrade Voltage Issue [Resolved]

TheWhrl · 1733

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Offline TheWhrl

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on: June 14, 2015, 02:05:05 PM
Hey everyone!

Built my Crack a few weeks ago and its pretty awesome.  I sat down this weekend to install the Speedball upgrade and I'm have issues with the voltage checks on 2 terminals.

On terminal 5 I'm getting 158 where  it should be 75-90.  And on terminal 9 I'm getting 150 where it should be 100.  Also the LEDs on the board nearest the headphone jack are dimmer than all the others.  They are on, just not as bright.

I've read through some of the other posts with issues and I've made sure that the correct transistors are on the correct boards and the LEDs are facing the correct direction.

Can someone give me a good place to start the troubleshooting?

Thanks,

Adam Johnson
« Last Edit: June 16, 2015, 01:45:37 PM by TheWhrl »

Adam Johnson


Offline Paul Birkeland

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Reply #1 on: June 15, 2015, 07:10:33 AM
Do both LED's glow on the 9 pin socket?

If yes: you probably have R1 resistor values swapped between the small board that isn't working and the large PC board.

If no: you need to re-solder the center leg on the MJE-350 of the offending board.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline TheWhrl

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Reply #2 on: June 15, 2015, 01:34:42 PM
Hey Paul,

Thanks for helping me out with this.

Both LEDs do come on in the socket.

I have verified with my multi meter that the resistors on R1 are the correct values.

I re-solder'd all the points on the MJE-350 just to be sure.  Same thing.
« Last Edit: June 15, 2015, 01:53:11 PM by TheWhrl »

Adam Johnson


Offline Paul Birkeland

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Reply #3 on: June 15, 2015, 08:08:33 PM
I would check for a solder bridge under the PC board, something must be connected that shouldn't be.

-PB

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline TheWhrl

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Reply #4 on: June 16, 2015, 01:07:15 PM
Got it working!

Re-soldered the components on the buggy board and its good to go!  Everything sounds great.

Thanks for the help.


Adam Johnson


Offline Paul Birkeland

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Reply #5 on: June 16, 2015, 01:58:41 PM
Enjoy the tunes!

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man