Modifications for the Yaesu FL-7000

Modifications for the Yaesu FL-7000
FL-7000 10 meter transmit mods

Remove power and all other cables.
Remove 4 screws from top cover.
Remove top cover and right and left panels.
Remove 4 screws from power combiner unit and remove screen plate.
Locate switch so1 on the cpu unit and set to off position ( a small screwdriver can be used to reach switch)
Reassemble unit.

FL-7000 desensitize the protection circuitry

From: Howard Ryder W4NTW@ix.netcom.com

Most Yaesu FL-7000 Solid State Linears have a hypersensitive protection circuit that causes the "protect" to trip when no improper conditions exist. This modification will desensitize the protection circuitry; but still allow it to function when an improper condition exists.

The modification is as follows:

PROTECTOR UNIT

Remove D7006 P/N HZ15-1L
Remove R7029 P/N J02245102
Remove R7033 P/N J02245104
Remove Q7004 P/N G3107331Q
Add R7060 Resistor 10K 1/4w P/N J01225103 This resistor must be added from pin 1 of Q01 (1/2 of AN6552) to pin 5 of Q7003 (1/2 of AN6552) after removing R33 10ohms.I carefully snipped the lead in the center and put my 10K in series with the existing 10 ohm resistor.
NOTE: This has been edited from the original text, which "incorrectly" stated to run the resistor between pin 7 of Q01 and pin 5 of Q7003, thanks go to Vince for providing the correct information

POWER SUPPLY UNIT

Replace C8019 P/N K13179009 WITH 1uf 50VDC P/N 59V010M5X11TR5.

This capacitor goes between the base and emitter of Q8008 P/N 2SC2229.

NOTE:
The positive lead goes to the base of the transistor.I put mine in parallel with th existing 0.047.

ALIGNMENT OF NEW CICUITRY

CM COUPLER

Remove the ALC cable.
Remove P06 (J04) on the Auto Tuner Relay Unit
Key the driving radio in CW (FT-757, FT-767, etc)
Adjust the power output to 400 watts
Connect the Black lead of DC Voltmeter to pin 1 and the Red lead to pin 3 on the Protector Unit, OR connect the Black lead to ground and the Red lead to TP01 on the CPU Unit (use the 0.25V range on the DC voltmeter)
Adjust TC5001 for a MINIMUM reading on the DC voltmeter
After adjustment, reconnect P06 and the ALC cable

PROTECTOR UNIT

ALC METER AND ALC PROTECTOR ADJUSTMENT

Set the ALC pot fully clockwise (CW)
Apply +9VDC to TP7001
Adjust VR7008 to the right edge of the ALC zone
Set the ALC pot fully counter clockwise (CCW)
No adjustment on the SWR Protector VR7004 is required.

IC PROTECT ADJUSTMENT

Connect the DC voltmeter to the center of VR7004
Adjust VR7004 to 3.8VDC +/-0.1V

The correct resistor and capacitor are available from Yaesu if you desire.
TB-9601- Yaesu (562)404-2700

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