Time to get this site upgraded, so we are passing the hat around. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html
We appreciate your help
in keeping this site going.
Looks like late 60's to early 70's to me & it may well be a hybrid chassis with tubes & transistors & in some even an intergrated circut in the sound stage was used in that time.
Threaded Mode