Scott Dorsey wrote:

You guys are triggering my failing memory. I vaguely remember these
things...something like a black ice-cube with a little wires coming out
of them. Price was something like $1.29-$2.59. I'm struggling to think
of where I saw a magazine article about ho-rigging about three of these
together for something like an AM broadcaster or some such gizmo.
Woulda had to be PE, EI or R-TV-Experimenter in the mid-late 60s since
that was all I had access to.


Everybody and his brother made them. Philbrick, Hewlett-Packard, and
Opamp Labs are some of the ones that are still around today. But
ITI up in Maryland, Solid State Electronics Corporation, Modular Audio
Products. Oh yeah, and Burr-Brown got their start doing this kind of
thing. I think Stephens, the company that later made 2" tape machines,
also started out doing amplifier modules.
--scott


Well, in perspective, it sounds like some sort of cheapo stuff that
never really caught on...like those early TenTec modules.

-bm