Yaesu FL-110 modification for 5W drive
7-sep-2017 Schematic redrawn.
YAESU FL-110
REDRAWN FL-110 SCHEMATIC
Over the years, FL-110 schematics have become a rarity and what's on the Internet are mostly vage images. That's why they were collected and after a few nights of hard
work to decipher value and numbering of the components, a good readable design could be drawn.
Corrections and additions are not excluded
.
DESCRIPTION FL-110
This pre-WARC 10 - 160 m band solid state all-mode linear power amplifier with low-
pass filtering on six bands was produced for the Yaesu FT7 and FT310S/SD QRP
transceivers. It operates on the 160, 80, 40, 30, 20, 17, 15, 12 and 10 meter amateur
bands. Drive power is 15 watts CW/SSB, 4 watts AM/RTTY. Maximum input power of the
finals is 200 W SSB/CW, 75 Ws RTTY and 50 W AM. The front panel has a DELAY switch
to select FAST 0.1-0.2 seconds or SLOW 0.3-1.0 seconds to control carrier operated
change over time. The rear panel has 50 ohm SO239 input and output jacks. This
(120x100x200mm, 2.5 kg) device requires 13.5 VDC at about 17 A.
With this modification («fig) your QRP rig (FT-817 etc.) will put out the amplifier's rated 100 W. It will work into a 1 :
1.4 VSWR (SWR ≤ 1.5) when resistors of the input attenuator are removed and replaced. In addition it will allow 5 W
drive to full output. It does work on the WARC bands with slight decrease in output power due to the low-pass filtering
in the unit.
