Crazy George wrote:
"---do a bibliographic search of Engineering Index, or Scientific
Abstracts, or whatever that school has access to."

Excellent advice from George. Motorola`s Extender usually included a
switch on the radio control head to enable or defeat Extender operation.
The only reason I can think of to defeat Extender operation is to
demonstrate its effectiveness, which can be compelling.

The Extender works early and often to put a hole in the radio`s response
before adverse effects are generated within. The holes rarely detract
significantly from the signal.

Also look for Motorola TEK 21 Pulse Generator instructions. It is a
hand-held, battery-operated, zener diode noise maker used to optimize
Extender performance in the radio. The TEK 21 saves overheating a car
engine just to make ignition noise pulses to obliterate while tweaking
the Extender circuit and the the radio`s response.

Best regards, Richard Harrison, KB5WZI

Also, be aware that the "Extender" is somewhat different from the typical
noise blanker (at least in RCA units), in that these actually have a
SEPERATE reciever, that can be tuned to a nearby (but not necessarly the
same frequency) that you are trying to eliminate noise on. The output of
this is used to control a preamp on the frequency that you are operateing
on. This has a major advantage over the typical noise blanker, in that , a
strong nearby signal won't overload the extender , if it is aligned 2, or
3 megs away from the frequency range you want to operate (unlike in a
transciever, which operats at the IF frequency ). As a side note, these
make great noise blankers for 6 meters, and are virtually overload proof.
Been there, done that! Jim NN7K



Richard wrote:...
Crazy George wrote:
"---do a bibliographic search of Engineering Index, or Scientific
Abstracts, or whatever that school has access to."

Excellent advice from George. Motorola`s Extender usually included a
switch on the radio control head to enable or defeat Extender operation.
The only reason I can think of to defeat Extender operation is to
demonstrate its effectiveness, which can be compelling.

The Extender works early and often to put a hole in the radio`s response
before adverse effects are generated within. The holes rarely detract
significantly from the signal.

Also look for Motorola TEK 21 Pulse Generator instructions. It is a
hand-held, battery-operated, zener diode noise maker used to optimize
Extender performance in the radio. The TEK 21 saves overheating a car
engine just to make ignition noise pulses to obliterate while tweaking
the Extender circuit and the the radio`s response.

Best regards, Richard Harrison, KB5WZI

"Richard Harrison" wrote in message
...
Crazy George wrote:
"---do a bibliographic search of Engineering Index, or Scientific
Abstracts, or whatever that school has access to."

Excellent advice from George. Motorola`s Extender usually included a
switch on the radio control head to enable or defeat Extender operation.
The only reason I can think of to defeat Extender operation is to
demonstrate its effectiveness, which can be compelling.

Richard:

One of the problems with the first production Extenders was no limit on the
total duration blanking. Since the individual pulse length was fixed, it
was possible to get 100% blanking on a readable signal, with the right noise
pulse length and rate. Motorola figured this out about the same time we
did, and quietly modified the circuitry to limit total blanking percentage.
On the other hand, the salesmen with one noisy spark plug in their demo
vehicles loved the switch. But, that's been 40+ years ago, and the details
are hazy.

--
Crazy George
Remove NO and SPAM from return address
snip

Best regards, Richard Harrison, KB5WZI