> Just to be clear the "drop" is planned, it is designed
> so that when multiple cars are on the same scene only
> one of them has a PAC-RT in operation, otherwise it would
> be a zoo-so the drop is really the synchronization of
> multiple PAC-RTs,
The drop is a receiver "sample window" to allow the person
(officer) with the portable the ability to quickly capture
the return path (transmitter control) back to the dispatcher.
Multiple "vehicular repeaters" listen for both activity and
tones/codes to setup and maintain a queue of operation so
only one repeater responds within a very local on scene
coverage area.
The sample and priority window values can be adjusted or
disabled if you only have one unit for personal use or
don't expect to use it for fast reply (emergency service)
work.
> ..the CHP, and Nevada used to use PAC-Rts.
Pac-RT is the Motorola Name, GE made a version and Pyramid
currently makes and sells them. (of course I'm a Dealer
for Pyramid). I'm told Vertex and probably Icom also
make them.
Most of the current CHP vehicles use the GE or a special
Pyramid (clone of the GE) unit.
> Also, today you can find a lot of the mobile repeaters
> around-and they make good portable repeaters-
The Motorola and GE repeaters have specific special cables
to interface to different radio models. You would normally
need the proper cable and in some cases a matching radio
with the corresponding control/interface circuit. The Pyramid
and newer brand repeaters are much more generic in regards
to the different radio brands/models they work/interface
with.
> HOWEVER, most of them, at least the GE ones, made sure
> that the receiver sensitivity was very poor so that it
> only picked up local HT traffic.
A target value of about 50uV (micro volts) RX Sensitivity
was specified by a number of agencies. Two officers on each
side of a freeway/highway should be able to operate independent
of each other.
> If you have one you will find that in the first receiver
> stage-the ICOM and associated components, there are a number
> of caps which have been left out in order to keep the
> receiver deaf.
I've seen resistive pads and on board attenuators used to
"numb up" the receiver front ends. They can be removed easy
enough...
> > I always found their selection of radios to be a bit
> > odd until about 10 years ago. For a while they would use
> > the GE system in the car and a Motorola for other systems,
Government Public Safety (an oxymoron)
> > but the two would never really synch properly and there
> > was always the drop out every few seconds that was only
> > about a half second long but none the less annoying!
That is the receiver listen window mentioned above...
> > I think they have changed systems now and don't have
> > this issue anymore.
Can be different sounding by design and programming... see
the above text.
> > Oh how I use to miss the days of California, now you
> > couldn't pay me enough to move back!
Plenty of work out here... minimum wage and all the pride
you can swallow.
s.
