From the September 1979 issue of Radio-Electronics magazine:

Bearcat Thin Scan Portable Scanner

While portable scanners have been around for some time, few have been classed as true pocketable receivers. Bearcat's new Thin Scan is indeed pocketable. Measuring only about an inch thick and 2 1/4 inches wide, the scanner will fit in most pockets with ease. Its 5 1/2-inch height poses no particular problems, either. Nor does its 7 ounce weight.

The Thin Scan comes equipped with two antennas. More than likely, the user will want to sport the "rubber ducky" flexible antenna. A thin, insulated wire antenna is also provided that may be used where unobtrusive reception is necessary. The wire antenna may be routed anywhere that is convenient, with some reduc- tion in reception range to be expected because of body capacity.

The appearance of the little scanner is handsome and conservative. The black case is accented by a metallic-brown front bezel. A row of LED's signal the channel scanning sequence on the front panel.

Functionally, the Thin Scan (model two-four) is a four channel, two band (high and low VHF) crystal controlled receiver. It is powered by four AAA cells, with a nickel-cadmium charging provision at a side jack. An external power supply jack is also provided for long-term operation from an AC source. Current drain is nominally 20 mA squelched, 50 mA at full output.

Thumbwheel controls for volume and squelch are conveniently located on the side, making adjustment quite natural. For privacy, an external earphone may be plugged into an audio jack on the top of the receiver.

Channels are individually controlled by lockout switches. Manual pushbutton stepping from channel to channel is also allowed by a fingertip control. The internal 2-inch speaker is driven with up to 100 milliwatts of audio, adequate for any personal monitoring. Audio remains quite intelligible (10% total harmonic distortion) even at high output levels.

Crystals may be mixed between high- and low-band in any proportion. An automatic socket switching arrangement accommodates the pleasure of the user. The Thin Scan is a double conversion superheterodyne, with IF's of 10.8 MHz and 455 kHz. The crystal formula for low band selection is:
receive frequency + 10.8 MHz = crystal frequency.

At high band, the formula becomes:
( receive frequency - 10.8 MHz ) / 3

Crystals may be ordered as type number A-135 from Electra at $5 per frequency.

Factory alignment is optimized for midband in the 33-47 and 152-164 MHz ranges. Mid-band sensitivity is advertised as typically 0.6 microvolt. In fact, our lab measurements confirmed this approximate sensitivity for 20-dB quieting. Sensitivity decreases to about one microvolt at the ends of the alignment ranges. Although not quite so sensitive as more elaborate and expensive scanners, it is perfectly adequate for the local use for which such a device is typically purchased.

Scanning rate is 8 channels-per-second. Squelch sensitivity is near 0.5 microvolt, adjustable to 2 microvolts by the squelch control. Spurious signals are rejected some 50 dB, with images down 35 dB. Modulation acceptance is designed for narrowband ±5 kHz.

The internal circuitry is very straightforward, using recently developed IC's for communications applications. A Motorola MC3357 FM IF IC drives an LM386N audio amplifier. All RF and oscillator stages are discrete transistors. Adjacent channel selectivity is controlled by ceramic filters.

The circuitry is designed so that the oscillator will not drop out until battery voltage has been depleted to about 4 1/2 volts. As with all battery operated equipment, it is a good idea to check the scanner briefly for operation after long periods of inactivity to make sure that the batteries are still functional. This will help protect against possible battery leakage damage. Better yet, remove the four AAA cells until the unit is to be used again.

We found the Thin Scan to be attractive, reliable, and quality built. It is manufactured offshore for Electra by a prominent electronics firm. The model two-four Thin Scan has a suggested retail price of $149.95. Available from Electra, 300 East County Line Road, Cumberland, IN 46229.

It first appeared in the 1976 catalog ("New for 76").

It was advertised in, among other publications, the February 1975 issue of Popular Science.

Introduced in 1984 as catalog number 20-104.