parnass@ihu1h.UUCP (Bob Parnass, AJ9S) (01/15/86)
x Scanner Survey: Bearcat Bob Parnass, AJ9S 800XLT: 40 channels in two banks. Covers 806-912 MHz, as well as of vhf, uhf, and aircraft bands. Receives 10 meter fm and all of 6 meters, as well as federal portions of vhf and uhf bands. Fewer birdies on vhf-lo band than other scanners. Scans and searches very fast. Clean, robust audio output. Extremely sensitive, but very prone to over- load by strong signals when connected to outdoor antenna. Too much play (hysteresis) in squelch adjustment - can be improved by changing one resistor. Positive terminal in memory backup battery holder installed backwards in early units, allowing memory loss when scanner unplugged from AC outlet. Tunes in increments of 12.5 KHz on 800 MHz band, whereas cellular telephones are on 30 KHz channels. BC350: 50 channels in 5 banks. Includes aircraft. Used to be Bearcat's top of the line, overpriced scanner but never very popular, now discontinued. Dual use keyboard and display allowed 8 text characters to be associated with each channel, a feature clumsily implemented, and awkard to use. Units plagued with various hardware problems including bad memory ICs and short life power transformers. Firmware bugs without cures. The BC300 is a much better scanner than the BC300, and at a lower price. BC300: 50 channel top of the line scanner. Service Search feature contains 11 ROM banks of preprogrammed channels. Switching power supply failure noted in early units due to insufficient capacitance - component value was changed in newer units. Schematics show at least 100 components changed between earliest and later units. Preset squelch pot, mounted internally on circuit board, misadjusted in new units - adjustment usually required after burn-in period. Good sensitivity. Built in clock. I leave it on 24 hours a day. This is a favorite. BC20/20: 40 channels. Reasonable number of features. Ser- vice Search for Marine and Aircraft. LED readout. Good scanner, but tinny audio. BC250: 50 channel discontinued model. Rich in features, but lacks aircraft band and 144-146 MHz. Search and Store feature extremely useful for finding federal frequencies. Clock. High frequency of repair. Power transistors not heat sinked adequately, causing heat damage to surrounding components and ciruit board. Digital circuitry very sensi- tive to glitches caused by static and AC line spikes. Avoid 1978 or earlier vintage units. All BC250s use custom ICs (e.g., IC6, a divider chip, mfd. by Exar), which are now discontinued, so factory service is no longer available from Uniden. BC260: Super heavy duty metal cabinetry and lighted con- trols, aimed at mobile use for firemen, police, etc. Few frills, only 16 channels, no aircraft, but generous coverage of federal bands omitted in the older Bearcat scanners. Good sensitivity. Lots of audio. Backlit keyboard allows operation in the dark, but the keyboards on some units require high pressure to operate. Brightness control for display and keyboard, but multiplexor circuitry for vacuum fluorescent display produces audible whine which may be annoying in a quiet room. Method of connecting an external speaker is awkward. BC100: First programmable portable. Be prepared for at least one repair in the first year. Early units, with threaded antenna connector, have high frequency of repair, particularly LCD readout, keyboard, and battery holder. No battery backup. Poor case design in early units caused bat- tery to disconnect from radio, resetting microprocessor and clearing memories. No priority channel or aircraft band. Some people swear by the BC100, others swear at them. BC101: First Bearcat synthesized unit. 16 channels, no priority. Frequency programmed in binary by setting toggle switches on front panel after looking up code in code book. No frequency readout. Uses custom IC for CPU, now discon- tinued, so factory authorized service is no longer avail- able. -- =============================================================================== Bob Parnass, Bell Telephone Laboratories - ihnp4!ihu1h!parnass - (312)979-5414