User manual RADIOSHACK PART 2 PPS 12-17 PART 2

[. . . ] RF Section Weak or no reception Is sensitivity on all bands abnormal? NO YES Defective IC11. NO Is the voltage of each pin of IC11 per Tabel A? Check incorrect band control IC. YES Check the subsequent circuits of the band control circuit. Table A IC11 Pin No. [. . . ] Or, defective IC204 (CPU). 13 DSP Section (DSP Circuit Test Program) Turn on the scanner, and press 0 then TEXT while Welcom to Digital Trunking appears. Connect the signal generator to ANT jack. Set the signal generator frequency to 868. 5125 MHz, 10 uV output, 1 kHz at 3. 6 kHz modulation. Press ENTER to start DSP circuit test program. Does the scanner's display show DSP Test 1 Freq / Amp1 TEST PASSED ENT for Next?YES Press ENTER. NO Check "DSP Section (Digital Audio, etc. )" section on Page 15. Does the scanner's display show DSP Test2 DSP Loopback Audio On Press Enter?YES Press ENTER. NO Defective IC3, C53, C57, R49, IC204, and/or associated circuit. Does the scanner's display show DSP Test3 DSP Loopback Audio Off Press Enter?YES Press ENTER. NO Defective IC3, IC204 and/or associated circuit. Does the scanner's display show DSP Test4 Flash CRC Ck TEST PASSED ENT for Next?YES Press ENTER. NO Defective IC204, IC210, IC209, IC212 and/or associated circuit. Does the scanner's display show DSP Test5 Flash Lock TEST PASSED ENT for Next?Press TRUNK to reset and restart the scanner. 14 DSP Section (Digital Audio, etc. ) Receive a frequency with FM mode, in manual mode. (Manual mode turns on digital decode. ) Is voltage okay on C291 (3. 5 V), and C292 (1. 8 V). [. . . ] Also check that IC209 pin 27 goes low when receiving IMBE, and IC204 pin 54 goes high when receivng IMBE. Defective IC211. 15 [. . . ]