Bottlehead Forum

General Category => General Discussion => Topic started by: docbob52 on April 26, 2013, 07:25:08 AM

Title: Need help trouble shooting Foreplay Extended III upgrade
Post by: docbob52 on April 26, 2013, 07:25:08 AM

After installing the upgrade, I note that LEDs on  the c4s board on the A socket do not light up when plugged in.  The LED's on the the B side and the Shunt regulator board all light up correctly. Without removing the A side C4s board I have checked all point to point wiring and the pc board and all appear to be correct.

What should be my next step?

All help appreciated.

Robert Howard,

Troy, Al.

Title: Re: Need help trouble shooting Foreplay Extended III upgrade
Post by: docbob52 on April 26, 2013, 07:52:09 AM

BTW, I got abnormal readings on Terminals:

Terminal 12:    I got 0 volts and should have been 150v

Terminal 15:  I got 1v and should have been 75v

Terminal 31:  I got 146v and should have been 75v.

Title: Re: Need help trouble shooting Foreplay Extended III upgrade
Post by: Doc B. on April 26, 2013, 07:54:41 AM

Make sure that the proper transistors are in the proper positions. There are some labeled 2N2907A and some labeled 2N2222A. They look the same, but are different. Also double check the orientation of the silver end of the LEDs. Also make sure the correct resistors are in the correct positions.

Title: Re: Need help trouble shooting Foreplay Extended III upgrade
Post by: docbob52 on April 27, 2013, 04:30:18 AM

Thanks Dan,  I found some reversed diodes and transistors.  Dyslexia strikes again!