FL7000 Tech Bulletin TB-9601- Protector Unit Modification
The FL-7000 has a hypersensitive protection circuit that causes
"Protect" to trip when no improper condition exist. This
modification desensitizes the protection circuitry; but allows it to operate
improper condition occurs.
PROTECTOR UNIT MODIFICATION
Remove following components from Protector Unit Board:
Add 10K resistor where R-33 was removed. (This is between
pin 1 of Q-O1 and pin 5 of Q-O3.)
POWER SUPPLY UNIT MODIFICATION
Remove C-19 (0.047)
Add 1mf 50 VDC capacitor in place ofC-19. (This is between
the base and emitter of 0-08. Put positive (+) to base of 0-08.
1. Remove the ALC cable
2. Remove PO6 (J04) on the Auto Tuner Relay Unit
3. Key the driver radio in CW mode.
4. Adjust power output to 400 watts
5. Connect negative (-) lead of DC voltmeter to ground
and the positive (+) lead to TP01 on the CPU unit. (Use
the lowest dc range on voltmeter)
6. Adjust TC5001 for a MINIMUM reading on voltmeter
7. Reconnect PO6 and the ALC cable.
ALC METER AND ALC PROTECTOR ADJUSTMENT.
1. Set the ALC pot fully clockwise
2. Apply +9 volts DC to TP7001
3. Set meter select to ALC position
4. Key the driver radio
5. Adjust VR7008 to the right edge of the ALC zone
6. Set the ALC pot fully counter clockwise.
IC PROTECT ADJUSTMENT
1. Connect the negative lead ( -) of DC voltmeter to ground
and the positive lead (+) to the center of VR7004
2. Without keying driver radio adjust VR7004 to 3.8 volts
+1- 0.1 volt
This completes the modification and testing. It will be
to readjust the ALC pot for 500 Watt output on the Amplifier PO
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