Section 2
INSTALLATION #6
Installation #6 applies to older Uniden 858 AM radios. This installation
is identical to
installation #5 except for the following:
1. Step #3-Locate
and identify 8104 (5.6K) that connects Pin 2 to Pin 3 of the 858 chip.
2. Step #-Remove the one side of 8104 that is connected to Pin 2 of the
D858 PLL Chip and install the center of Coax #2 to this lead of 8104.
3. Step #6-Locate and identify C140, a 1 mfd capacitor, and install a
20-22 gauge jumper wire across it's leads to remove it from the circuit.
4. Step #8-Connect the red wire to the 12 volt source of the radio.
5. Remove TR-22 to comply with FCC regulations.
NOTE: Loop Filtering: On some 1400 installations additional loop
filtering may be required because of the close channel spacing and large
badwidth.
By adding the modifications
below, low end stability will improve.
1. Add a 1 K resistor in series with R103.
2. Series a 10uf electrolytic capacitor and a 10K pot from TP5 to ground.
Adjust 10K pot for best VCO stability. Observe polarity.
This completes the
installation procedure. Before operation, the DS-400 must be programmed
and the radio must be realigned. Turn to the programming section and proceed.
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