User manual RADIOSHACK PART 1 PPS 1-11

[. . . ] 5 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Printed Circuit Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [. . . ] 3 BLOCK DIAGRAM 4 ALIGNMENT AND ADJUSTMENT ALIGNMENT AND TEST POINTS TP2 L2 T1 T2 L27 L22 GND TP3 VR2 VR3 TP4 TP5 L23 VR4 TP1 ALIGNMENT PREPARATION Test Equipment Required l Oscilloscope l DC SSVM l AM/FM signal generator (25 to 1300 MHz) l Frequency counter (800 MHz) Notes: l Use non-metallic tuning tools l The test equipment and receiver should be warmed up for at least 10 minutes before proceeding with alignment. l The signal level from the generator should be kept as low as possible to obtain a usable output. l The memory backup circuit can hold the programmed channel memories for about one hour. Program Channels 000 through 011 as follows: Channel 000 001 002 003 004 005 Frequency and Band Mode 960. 000 MHz (FM) 25. 000 MHz (FM) 1300. 000 MHz (FM) 216. 0025 MHz (FM) 512. 000 MHz (FM) 174. 000 MHz (FM) Channel 006 007 008 009 010 011 Frequency and Band Mode 173. 390 MHz (FM) 173. 420 MHz (FM) 154. 5475 MHz (FM) 124. 000 MHz (AM) 154. 610 MHz (FM) 406. 000 MHz (FM) 5 ALIGNMENT PROCEDURES PLL2 VCO Alignment Control Setting OFF/VOLUME control: ON. See Table 2 and 3. PLL1 VCO1 Alignment Control Setting OFF/VOLUME control: ON. (No adjustments are necessary for the coil. ) See Table 2. PLL1 VCO2 Alignment Control Setting OFF/VOLUME control: ON. (No adjustments are necessary for the coil. ) See Table 2. Channel 000 001 002 003 004 Frequency 960. 000 MHz 25. 000 MHz 1300. 000 MHz 216. 0025 MHz 512. 000 MHz Voltage 17. 0-19. 0 volts at TP2 2. 0-5. 0 volts at TP2 19. 0-21. 0 volts at TP2 1. 0-4. 0 volts at TP2 1. 8-2. 2 volts at TP3 DC SSVM Table 2 DC SSVM Unit Under Test TP3 Unit Under Test TP2 Figure 1 6 Figure 2 Adjustment of Coils L22, L23, and L27 Use non-metallic tuning tool Each coil should be adjusted carefully by changing the pitch of the coil little by little using a nonmetallic tuning tool as shown in Figure 3. Increase the pitch of the coil when the measured voltage at TP2 or TP3 is higher than the voltage listed in Table 2 for the PLL2 VCO alignment, PLL1 VCO1 alignment, and PLL1 VCO2 alignment. Decrease the pitch of the coil when the measured voltage at TP2 or TP3 is lower than the voltage listed in Table 2 for the PLL2 VCO alignment, PLL1 VCO1 alignment, and PLL1 VCO2 alignment. Coil PCB Notes: Figure 3 l Be very careful when doing coil pitch adjustment because it greatly affects the frequency. Table 3 455 kHz FM Discriminator Coil Alignment Control Setting OFF/VOLUME control: ON. Test Instrument Connection Connect the signal generator to the ANT jack and the DC SSVM to TP4. Adjust T2 Result Set the signal generator freuqency to 154. 610 MHz, 100 uV output (no modulation) and adjust T2 for 1. 3 +/- 0. 05 volts on the DC SSVM. DC SSVM ANT. Jack FM Signal Generator Unit Under Test TP4 Figure 4 1st IF (380. 8 MHz) Coil Alignment Control Setting OFF/VOLUME control: ON. Test Instrument Connection Connect the signal generator to the ANT jack and the oscilloscope and an 8-ohm dummy load to the headphone jack. Set the signal generator freuqency to 124 MHz, AM: 60% modulation at 1 kHz and RF output under 1 uV. Jack AM Signal Generator Unit Under Test Headphone Jack 8ohm Figure 5 7 3rd Local Alignment Note: You must adjust Reference Frequency Osc. Alignment before you adjust this procedure. Control Setting OFF/VOLUME control: ON. Select channels 006, 007 and 008. Test Instrument Connection Connect the signal generator to the ANT jack and frequency counter to TP5. [. . . ] Then press ENTER. The scanner shows EEPROM TEST Mode and automatically starts the EEPROM test program. When the scanner shows EEPROM OK!Turn off the scanner. Note: This procedure (EEPROM check program) clears all information you stored in the scanner's working memory. 9 Turn on the scanner, then the scanner initialize the working memory. Microprocessor Check Power ON. Does the display work properly? [. . . ]