This page contains the collection of all the modified or "add-on" circuits. All of these schematics also appear on their own, respective
pages with detailed construction information and application data. I added this page only as a collection point for your convenience.
The schematics are all in .jpg format. If you want to retain a hard copy of these circuits for your reference, just right click the image
and select <save picture as>, then place it in a file or folder of your choice on your hard drive. You may later open the file is a
suitable photo editor (Photoshop, Photohouse, ACDSee) and adjust the size appropriately for printing.
GE (SUPER) Superadio-III
Hot Rodding the SR-III
The Head End Circuit. This contains DC
static drain and RF impulse protection, a
tapped, switchable impedance matching
transformer, a stepped, switchable
fixed-increment attenuator, a selectable-Q
preselector (band pass filter), a
preamplifier, and an output matching
transformer. This circuit may also be used
as a stand alone Signal Preconditioner as
well, but here is specifically designed for
this SSR-III Project.
This circuit is an optional Noise and
Impulse Blanker that functions entirely in
the analog domain. Although not as totally
effective as an equivalent digital version,
it was designed to eliminate the need of
any digital circuitry within the SSR-III.
Here is the existing SR-III audio preamp
and tone control circuit. it is annotated
with the tap points (A thru G) for the
modified audio section.
The switching circuitry for the use of the
separate Bass and Treble tone controls
and the added Narrow/Wide function.
This circuit allows the use of separate
audio send for Pre and Post air-check
recordings, and also allows for the use of
the audio power amp by external signal
sources. It is a kind of mini-mixing board.
These taps also drive the "VU" and
The relative tone and pass band functions.
The beginnings of the "S-Meter" and the
"Center Carrier" circuit to drive those two
...more to come during the development process.