I was responsible for all the circuit topologies for Crimson and on the 610 PCB Clive Powell did the track layout.
The early 610s had a PCB marked "610/35-B" and was on a blue substrate. The tracks lift easily when heated unfortunately. The circuit does not have massive power supply rejection due to it being generally battery powered. Sometimes the power supply and signals were carried via a 5 PIN 180 deg DIN cable from the stereo power amp. There were dropper resistors of value 680R which fed the on-board zeners D5,D6 12Volt with about 30 mA (less 10 mA for the active parts of the circuit).
Later 610s had a PCB marked "Crimson CPR2" which had TL431 shunt regulators on board with a total current feed of 20-30 mA. The regulators were set to between 10 to 15 volts according to when the PCBs were made.
All the 610 PCBs had this pinout:-
Pin 1 Left disc output
Pin 2 VCcc+
Pin 3 Vcc-
Pin 4 Left disc input
Pin 5 Right disc input
Pin 6 disc stage ground
Pin 7 Right disc output
Pin 8 Line stage output right
Pin 9 Balance pot right channel
Pin 10 line stage in right from volume pot slider
Pin 11 Line stage ground
Pin 12 Line stage in left from volume pot slider
Pin 13 Balance pot left channel
Pin 14 Line stage output left
Voume pots were all 47(50) K log dual. Balance pots were single gang and were 1k linear.
I have been working on the original "610/35-B" schematic and when I have it in electronic form, I shall be adding it to my webspace
http://homepage.ntlworld.com/bepowell/schematics/
Mail me on
[email protected] for any specific information.
Brian Powell