Modifications for the Yaesu
FT-33

19-07-1998 Extended frequency for FT-23,33,
and 73
Extended Frequency Enhancements for the Yaesu FT-23R(2M),
FT-33R(220), and FT-73R(70cm). (Revised)
Greetings and hello radio
amateur operators.
The topic is increasing the functional frequency
coverage of what has been probably Yaesu's most popular handheld
tranceivers.
To save manufacturing costs, Yaesu engineers designed
multiple personalities in the same CPU module found in the FT-23R, FT-33R,UHF
FT-73R and the FT-2008/7008 tranceiver. The FT-2008/7008 tranceiver is the
commercial version of the Ft-x3R series.
Unique features of this mod
include
- the just say Mao feature (**)
(NO FREQUENCY READOUT: Ch 1 thru Ch 9
appear on your display.
Great when you aren't looking and some fellow ham
tries to rip off your simplex frequency)
- the GREAT WHOPPER
(opens the CPU to 50-300 Mhz or 220-550 Mhz coverage.
Full (.100 Mhz to 999.9995 Mhz) adjustable freq coverage available so far only
on the FT-33R;this doesn't mean you can actually transmit but the Activity
light goes in TX and you get a good fake RF bargraph that indicates that you
can transmit on 750 MHz.
How to do it:
- Contemplate invalidating your warranty. No beginners beyond this point. If
you don't know how to solder, don't learn here. Ask an elmer to
assist.
- If you treasure your memories, write out your contents of your radio on a
piece of paper. When you make the changes, the CPU runs a small diagnostic and
see that the jumpers have been changed. It will ERASE ALL PRIOR
SETTINGS.
- Dissassemble your tranceiver.
- Find the line of solder connections running down the CPU board. GENTLY
move all wires aside so you won't melt them.
- Using solder wick and a Good low-power soldering Iron, see chart. Read
special notes for the FT-33R.
- Rebuild radio and count your blessings.
(**)NO FREQUENCY
READOUT
Removal of the solder bridge labeled number nine will activate
the commercial side of the CPU module. To flip to the amateur mode, you would
press F UP Arrow. To flip to the commercial mode, you would press F Down Arrow.
+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=
+=+=+=+=+=+=+=+=+=+=+= FT-23, FT-73R Chart =+=+=+=+=+=+=+=+=+=+=+=+=
50 to 300 Mhz spread 220 to 550 Mhz spread
-------------------- ---------------------
Open bridges 8,9 Open bridges 7,8,9
+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=
+=+=+=+=+=+=+=+=+=+=+=FT-33R Chart =+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=
Same chart as above, but I wanted to add my experience of the Yaesu FT-33R
220 Mhz radio.
When I removed number 7 and then did a cold reset , the CPU cleared and showed me a L and a freq. I put .100 in.
Press
D/MR. Then a U appeared. I turned the VFo knob until 999.999 appeared. Press
D/MR.
I also had to reenter the Repeater Split to the proper
value.
On the VFO, I could QSY down to those limits (using F UP/DN) and
listen to my local Channel 13 on 215.720/.660.
Yes, 216-220 Mhz is
available with this mod. Great if 216-220 is the next 220
subband.
Notes
1 Cold Reset of the CPU Board.
With the radio
upright and your nose pointing at the CPU board, look at the Lower Right Corner
of the CPU chip. You will see two parallel SMT resistors. Below them is a screw
with possibly a paper washer. To the right is a SMT device (it's a cap) with a
pointed end facing Left. Ground that point to the screw or to the case with a
flat screwdriver. Awhile doing that, cycle on/off the radio to ensure a good
reset. Remove screwdriver and then reassemble radio.
Dedicated
to:
----- the knuckleheads in Barry Electronics who said it was
impossible.
----- Yaesu Tech Support who claimed that there are no RESET
circuits in their radios, when their schematic diagrams say
otherwise.
