[jr_tech]

Early models:

Simpson 260 first model:
https://www.simpson260.com/260-1/simpson_260-1a.htm

Simpson 260 type 2:
https://www.simpson260.com/260-2/simpson_260-2.htm

Simpson 260 type 2A:
https://www.simpson260.com/260-2/simpson_260-2a.htm

Simpson 260 type 3:
https://www.simpson260.com/260-3/simpson_260-3.htm

AC scales look ok for a type 2, but the chicken head knobs don't... I believe they should be round.

On the other hand, look at this thread:
http://www.videokarma.org/showthread.php?t=268248

jr