PRO-23
(200-0104)                 Operation                  Faxback Doc. # 39634


After batteries, crystal(s) and antenna (telescopic or flexible) have
been installed, your PRO-23 is ready to use.

Turn power on by turning VOLUME to the right.  Turn SQUELCH to the minimum
position to the far left.  Set all the channel lock-out switches in the up
position, toward the LED indicators.  You should hear a rushing sound from
the speaker.

Turn SQUELCH to the right until the background noise abruptly stops.
You can't adjust SQUELCH properly while listening to a station, so wait
signals cease.  If you set SQUELCH correctly, the PRO-23 will appear
"dead" until a signal comes in; when a signal comes in, the Squelch
circuit will "open up" and you'll hear the signal.  When the signal
ceases, the Squelch circuit will "close" and cut out all sound until
the next signal comes in.

If you want the PRO-23 to scan the channels continuously for the crystals
you have installed, adjust SQUELCH as previously instructed, then set
the SCAN/MANUAL switch to the SCAN position.  The PRO-23 will constantly
scan each channel in sequence; when a signal appears on one of the
channels the receiver will lock onto that channel and you will hear the
signal.

If you do not want automatic scanning on one or more channels, push the
appropriate Channel Lock-Out Switch(es) down, or away from the LED
indicator.

If you want to stay tuned to one channel only, set the SCAN/MANUAL switch
to the MANUAL position (stop scanning) and then press MANUAL momentarily
to advance to the channel you want to listen to (as indicated by the LED
above that channel switch).  For MANUAL scanning, the receiver can be
either "squelched" (adjusted as previously indicated) or "unsquelched"
(the SQUELCH control set to extreme left).  For automatic scanning,
SQUELCH must be set to eliminate the background noise.


MAXIMUM SENSITIVITY RANGE

This Receiver will function adequately down to 118 and up to 136 and from
144 to 174 MHz, but with reduced sensitivity at the upper and lower
extremes.  For maximum sensitivity on the VHF-Aircraft band the channel
frequencies you choose should be within +/-3 MHz of 127 MHz (that is, in 
the spread of 124 to 130 MHz).  For the VHF Hi band, stay within +/-4 MHz 
of 153 MHz (that is, 149 to 157 MHz).  The superior reception spread of 6 
or 8 MHz (+/-3/4 MHz) can be moved up or down in either band of this 
Receiver (which should be attempted only by qualified Electronics Service 
Technicians who have adequately calibrated, precision test equipment).

TYPES OF SIGNALS YOU'LL BE ABLE TO MONITOR

Your community is alive with action constantly being reported on the
airwaves.  Your PRO-23 will automatically scan the airwaves to bring
you that action-your police force at work, a fire truck on a mission,
aircraft, Ham radio operators, highway and other emergency-type services,
some industrial services, some transportation service (taxi, trucks,
railroad), plus some government services.  Lots of things are going on
that most of us are never aware of.  But, with the right frequency
crystals in your PRO-23, you can monitor these exciting signals.
You'll have to do a little investigating in your community to find
out what services are active and their frequencies.  You will find
one of our books to be very interesting and helpful in this area:
REALISTIC GUIDE TO POLICE, FIRE AND AIRCRAFT RADIO.

What to listen for and where?  A specific answer is difficult.  Each
area of the country uses different frequencies.  All we can do is give
you some general pointers.

Find out if there is a local club which monitors these frequencies.
Often a local electronics repair shop that works on the equipment can
give you the channel frequencies used by local radio services.  A
volunteer police or fire employee can also be a good source of this
information.

An interesting service is the Mobile Telephone.  FCC has assigned channels
to this service in the range of 152.51 to 152.81 MHz at every 0.030 MHz
(channels are 30 kHz apart).

As a general rule on VHF, most activity will be concentrated between
153.785 and 155.98 and then again from 158.73 to 159.46 MHz.  Here you'll
find local government, police, fire and similar emergency services.
If you are near railroad tracks, listen between 160.0 to 161.9 MHz for
signals.

You can listen to communications between aircraft and airport control
towers in the 118 - 136 MHz range.

If you live near the coast or the Great Lakes, another interesting service
is Marine Radiotelephone.  (It operates in the frequency range of 156 to
158 MHz.)

Some of the more interesting frequencies are:

  156.8 MHz for calling and distress signals
  156.3 MHz for intership safety, plus search and rescue
  157.1 MHz U.S. Coast Guard Liaison
  156.425 MHz non-commercial ship-to-ship/ship-to-coast/coast-to-ship

Other frequencies may be of special interest.  Check with local Coast
Guard offices.

NATIONAL WEATHER SERVICE RECEPTION

Continuous weather broadcasts are transmitted 24 hours a day in many parts
of the country.  If you are using a crystal set to one of the three
channels assigned (162.55, 162.40 or 162.475 MHz), your PRo-23 will
automatically lock-in on that channel, since the broadcasts are
continuous.  To prevent automatic locking, set the channel lock-out switch
for that channel to the off position (down).  When you want a weather
report, set the lock-out button to the on position (up) for that channel.
Check with your local FCC office or the Weather Bureau to find out which
of the three frequencies (162.40, 162.55, or 162.475 MHz) is used in your
area.


ACCESSORIES

Your PRO-23 can be powered from any source of 6 volts DC, negative ground,
by connecting the external power source to the PWR jack.  Using an AC
adapter will save on batteries; so, if you intend to use the PRO-23 in a
location where 120 volts is readily available and it does not need to be
moved around, consider an adapter.  Radio Shack has two power adapters
which you might be interested in.  Catalog Number 20-189 is an adapter
for 120 volts AC, specifically designed for Radio Shack's pocket scanners.
It providers 6 volts DC and can be used either as a Charger or an AC
Adapter.

Catalog Number 270-1561 is a power adapter for plugging into a cigarette
lighter socket in your vehicle and providing either 6 volts DC (positive
or negative-set for tip negative).  This will permit you to use the PRO-23
in your car or truck without wearing down your batteries.  This adapter
can also be used with either CHG jack (to recharge nickel-cadmium
batteries) or with the PWR jack.

If you use our special DC auto adapter with this scanner, be sure to

1.  Use the correct mating plug.
2.  Use the 6V switch setting.
3.  Use Negative tip polarity.

(LB/km-05/20/1997)

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