LA9PJA - Yaesu FL-7000 Linear Amplifier.

FL-7000 Amplifier

Antenna Output Selector Repair
Photo of the Author's FL-7000 Linear Amplifier, before repair.
Photos by Carlos Ferreira. Copyright 2006
My FL-7000 Output Selector Repair.
In August 2006 while installing an antenna switch at my tower, I found out that the antenna selector ports on the back of my FL7000 Linear Amplifier weren't working porperly. So after contacting Bill Grassa, I got the amp manuals and the values wich should be outputed from the selectors, wich again confirmed my suspicious findings that there was something wrong. After checking the readings, I oppned the amp as the photos on the right shows using the following procedure: 1 - Removed the side rails, top and bottom covers. 2 - Removed the end trim pieces and screws holding the front panel.
3 - Removed the top front panel screws on the sides to allow the front panel to swing open. 4 - While the front panel was resting 90 degrees from the chassis, I had now access to the processor board that is mounted on the front
http://www.qsl.net/la9pja/fl7000.html[2/25/2009 3:11:00 PM]
panel. 5 - Removed the 3 pcs. (2SA733A) transistors found at Q004, Q005 and Q006 positions. 6 - Replaced Q004, Q005 and Q006 with 3 new (2SA733A) transistors. 7 - Attached the front panel into place by performing the above procedures on 1, 2, 3 and 4 but in reverse this time. 8 - Connected the amplifier to the control cable of the FAS-1-4R Remote antenna Switch and tested the antenna selector on the amplifier. 9 - The selector was now working and selecting the correct antennas inputs into the FAS-1-4R Switch. 10 - Closed down the remote switch and installed up on the mast and again made a new test, now the antenna selector was working properly and swithcing into the right antennas, either manually or in automatic mode from radio. Again, I would like to credit this repair to Bill Grassa for his technical support via e-mail from St. Cloud, FL - USA.

Technical Documents:

FL-7000 Manual FL-7000 Schematics FL-7000 Schematics 1 FL-7000 Schematics 2 FT-1000 Series Band Data cable FT-800 & 900 Series Band Data cable Housings, Plug & Receptacle 9 circuit Molex: Crimp Terminal Female for 24 -> 30 GA wire 8 Pin: Mini-DIN Plugs Datasheet 2SA733 Datasheet SC2652 FAS-1-4R Wiring.