Radio Shack PRO-2036 Scanner

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  • Radio Shack PRO-2036 200-Channel Home Scanner.
  • Uniden Bearcat BC-890XLT Scanner
  • Albrecht AE-60T Scanner

The Radio Shack PRO-2036 and Uniden BC890XLT are equivalent (see reviews in June 1995 Monitoring Times). The scanner comes with weather alert, ctcss and coverage areas within 29 to 956 MHz. Also features Auto-store, Auto-sort, Rotary control, and Channel count.

Uses an AC power adapter and will work on 12VDC mobile.

specifications

Sensitivity

  AM: 20 dB (S + N/N) at 60% modulation
      108 to 136.975 MHz.........................................3 micro V
      225 to 399.9875 MHz......................................1.3 micro V
  FM: 20 dB (S + N/N) at 3 kHz deviation
      29 to 54 MHz.............................................0.6 micro V
      137 to 174 MHz...........................................0.7 micro V
      216 to 224.9875 MHz......................................0.5 micro V
      400 to 512 MHz...........................................0.5 micro V
      806 to 956 MHz...........................................0.7 micro V

Birdie Frequencies:

31.05 MHz             124.20 MHz
41.40 MHz             134.55 MHz
51.75 MHz             144.90 MHz
113.85 MHz            155.25 MHz

review

This would have been a great scanner, except, the rigid frequency step rate is preset for the band. This is a problem. For example, a repeater on the 1.25m ham radio band might be at 224.760 MHz. This scanner will not accept the frequency as valid, and will fall back to 224.7625 because it increments at 12.5 KHz steps between 216 - 224.9875 MHz (FM). At 225 MHz the step remains 12.5 KHz, however, modulation changes from FM to AM.

use

1) to program a frequency into memory

You want to be in channel mode. Select manual mode. dial in the desired channel. use the keypad to enter the frequency. press the "E" button to enter the frequency into that memory channel.

support

factory reset

To do a hard reset: Hold 2, 9, and manual keys while turning on the radio to reset the processor.

cellular unblock

This is the mod to restore full 800MHz reception.

BC890XLT-800MHZ FULL RESTORE

  1. REMOVE ALL CABINET SCREWS.
  2. REMOVE 4 FACE PLATE SCREWS AND 1 BRACKET SCREW AT CENTER OF MAIN BOARD.
  3. CAREFULLY DEPRESS THE OUTSIDE EDGES OF FACEPLATE SHIELD AND TILT DOWN.
  4. UNPLUG J4 AND J5 AND RIBBON CONNECTORS J501 J502 AND J503.
  5. REMOVE FACEPLATE AND LOGIC BOARD.
  6. POSITION BOARD SO MICROPROSSOE CHIP IS ON LEFT AND MEMORY BATTERY ON RIGHT.
  7. LOCATE THE 3 CHIP RESISTORS AT CHIPS UPPER RIGHT..MARKED 104 AND CAREFULLY DESOLDER.
  8. INSTALL THE CHIP RESISTOR AT THE 2 EMPTY PADS CLOSEST TO MEMORY BATTERY.
  9. REASSEMBLE CAREFULLY IN REVERSE ORDER.
  10. TEST BY ENTERING FREQ. AROUND 870 MHZ.

discriminator tap

Using a discriminator tap gives you access to the scanner baseband audio. This unprocessed audio is necessary for digital decoding and other related things you can accomplish using computer software via the sound card.

The receiver IC is a JRC 3359. The unfiltered discriminator audio can be found on pin #10 of IC #3, 3359DA. Pin #10 is on the top right corner of the chip. Solder to the lead to the resistor at TP3 which is connected directly to PIN #10 of the IC. You should put a 10K ohm resistor in series with a 10 μF tantalum capacitor to protect the scanner from short circuiting. Connect the (-) ground wire to the chassis.

Jrc3359discriminatortap.jpg

More on the purpose of the 10K resistor: Connecting or disconnecting an interface to the discriminator output might cause a short-circuit. The limiting resistor prevents the discriminator IC from being loaded or damaged. Further to that, it prevents your PC's microphone or line input from being overloaded.