[sdiy] ARP 2500 schematic question for 1027 Cocked Sequential Controller

Donald Tillman don at till.com
Wed Oct 1 17:12:25 CEST 2014

On Sep 26, 2014, at 9:43 AM, Travis Thatcher <recompas at gmail.com> wrote:

> Trying to troubleshoot why step 8 of an Arp 2500 1027 Clocked
> Sequential Controller does not produce any voltage on any of the 3
> outputs, nor does the gate out work. I'm wondering if anyone knows
> what chip/circuit the TD1-10 is and also what PL-#s are?
> http://www.guitarfool.com/ARP2500/images/1027_sch.jpg

Huh... I hadn't seen this one before.

It appears that the schematic for TD's 1-10 is shown on the inset on the right side.

PL stands for pilot light.

  -- Don

Don Tillman
Palo Alto, California
don at till.com

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