Jim's absolutely correct in everything he writes.
The only thing I'll add is you have much better protection with a front and rear
antenna than you do with a front only unit. One nice feature of the Valentine unit is
the bogey counter which displays the nuber of signals received at any one time and it
gives their direction also.
KW
Working in Radar and Radio much longer than I care to admit too : )
jim miller wrote:
> > SOME of the newest radar detectors do not emit the signal the trouper can
> > >detect
>
> The reason many radar detectors can be detected by a properly equipped police unit
> is that the detector uses a superhetrodyne receiver like your car stereo, your CB,
> or most any radio set of any kind. This circuit emits a low level signal than can
> be received by a receiver tuned to the band it is on. The police receivers are
> looking only for signals in the microwave band so they don't respond to your
> stereo or your CB. The signal is often strong enough to be heard from as far as
> 300 yards. The cure used in some of the new "undetectable" models is to shield
> the internal receiver so that its signal can be heard only a few feet.( usually 3
> to 5 feet). The police receiver is not sensitive enough to pick up these weak
> signals. This stealth technology is not new and was developed during WW2 to
> prevent the German subs from locating our ships by listening for their radio
> sets. These older shortwave receivers would emit a signal detectable for miles so
> shielded models were developed to prevent this. It was not necessary to shield
> radar detectors until some smarty developed the receivers for the cops. As you
> might imagine if somebody can invent a new trap device, somebody can find a way to
> defeat it. The new shielded detectors are as cheap as the older ones too. BTW I
> have had a grill mounted detector for several years and it will pick up rear radar
> from at least 1/4 mile.
> Jim in Waco.
> Ham call WB5OXQ for 25 years
> Radio station engineer for 30 years
> Waiting on 99 R/T (probably this coming week)
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