My main interest is to listen on the air band (118-137 MHz).
What's a good price for a Pro-42?
Advance Products Group
Landmark Graphics Corp.
>A local pawnshop has a Pro-30 they'll "let go" for $75.
>Is this a good deal?
>My main interest is to listen on the air band (118-137 MHz).
>What's a good price for a Pro-42?
The $75 price sounds high for Radio Shack's first programmable
portable scanner. The PRO-30 was a good scanner in its day, but
that was long ago and it's not attractive by today's standards.
It has only 16 channels, scans slowly, and requires two sizes
I've had 7 PRO-30s due to various defects. Here's a brief
report I wrote *several* years ago.
The Radio Shack PRO-30 Synthesized Scanner
Robert S. Parnass, AJ9S
I recently purchased a Radio Shack PRO-30 synthesized
handheld scanner. Here are some details:
o Price: $300.
o Batteries are not included. The PRO-30 requires 3
"hearing aid type" batteries for memory retention
and 6 AA batteries.
o Frequency coverage is fixed. The manual states:
"In case you're wondering, the tuning range of
your PRO-30 is permanently stored in the micropro-
cessor chip. There's no way it can be extended or
altered - even by a skilled electronics techni-
cian. So if you try to enter a frequency not in
the PRO-30's tuning ranges, you'll get an error
message every time!"
o 30 - 54 (includes entire 6 meter ham band)
o 108 - 136 (AM commercial aircraft band)
o 138 - 174 (includes some military frequencies
below the 2 meter ham band)
o 380 - 512 (several military and "secret" US
government frequencies in this range)
o Semiconductor components: 1 LSI microprocessor, 1
LSI PLL chip, 3 CMOS chips, 5 other chips, 39
transistors, and 75 diodes!
o Scanning rate: Fast = 10 channels/second, Slow = 5
o IF frequencies: 10.7 MHz and 455 KHz.
- 2 -
o Current drain (not including memory backup cells):
55 mA squelched, 100 mA unsquelched at full
o Priority Sampling: 2 seconds.
o BNC antenna connector. A multi band semi-flexible
antenna is supplied.
o The case is plastic, with a hinged, spring loaded
belt clip on the rear. The inside of the case has
been sprayed with some type of gold colored RFI
o The keyboard buttons are made of a *** type
material, that compress slightly when depressed.
An audio tone is used to confirm key depression.
o Three pushbutton switches on the top of the unit
duplicate functions on the front mounted keypad:
This allows the user to manipulate these functions
while the scanner is worn on the belt.
o The PRO-30 is made in Japan by GRE, the same com-
pany that makes Radio Shack's crystal controlled
o The owner's manual contains a block diagram, but
no schematic. I am told that a service manual,
with schematic, will be available for sale. The
owner's manual contains a list of "birdies."
Some early impressions:
o The scanner works quite well.1
1. The PRO-30 being reviewed is one of the first available
in the northern Illinois area. Early models of complex
radio equipment from other companies have been plagued
by several problems. Examples are the Drake TR-7
- 3 -
o The instruction manual is pretty good, although a
schematic should be included.
o The scanner is bigger than the Bearcat BC-100. No
leather case is available to protect the PRO-30,
so the scanner could be "bruised" in heavy ser-
o The LCD display contains several status indica-
tors, including a low battery warning message.2
The display is quite crisp and clear in bright
light, and when the internal dial light is
activated. It is difficult to read under low
lighting conditions and at various angles, a
characteristic of LCD technology.
o Striking a key does not always actuate the desired
function. If a key is struck off center, the
*** key top compresses without actuating the
switch mechanism. The user is made aware of this
situation when no audio tone is heard after a key
A nice aspect is that the keyboard is less prone
to damage if it is struck against the corner of a
o Sensitivity on UHF is at least as good as the
several crystal controlled portable scanners I've
aligned, maybe even better!
o In Search mode, scanning will stop only when the
radio is tuned to a station's center frequency. A
"window detector" circuit3 prevents lock up on
transceiver, the Bearcat BC-100 and BC-300 scanners, and
the Collins KWM-380 transceiver.
2. The user is also warned of failing batteries by a audio
3. A similar circuit is found in certain Bearcat
synthesized models, such as the BC-250. The original
patent for this circuit is assigned to General Research
Electronics (GRE), as are several other scanner patents.
- 4 -
o The internal construction looks decent. There are
two printed circuit boards in the radio, connected
via a multi pin connector rather than messy wiring
harnesses. The component designations (e.g. R102,
C212, etc.) are printed on the board. Resistors
are 1/8 watt and mounted vertically. Layout
appears clean, not overcrowded.
o The priority scan feature works well and uses a
"reasonable" algorithm, like that used in most
Bearcat and Regency scanners.4
o Audio output circuitry uses the LM386 audio
amplifier chip, producing about 220 milliwatts of
audio power out.5 This is a bit on the weak side
if you're using the scanner in a truck, or wearing
it in a noisy situation without benefit of an ear-
phone or external, clip-on lapel speaker. The
audio is crisp and clean, without synthesizer
o The 2nd IF, FM detector and squelch circuitry is
implemented using a Motorola MC3357 IC, now quite
common in scanners.6
4. The algorithms used in most Japanese 2 meter ham radio
transceivers, discussed in a previous article, are not
very useful to American amateurs.
5. The LM386 is also used in the PRO-24 crystal controlled
handheld scanner, reviewed in a previous article. In
both models, the speaker element is only rated for 100
6. The squelch function works quite well and is not plagued Locate transmitter sites with RadioMap(tm)
by the hysteresis problem found in the PRO-24.
Locate transmitter sites with RadioMap(tm)
7. PRO-30 MODS