Subject: VX-5R Expanded frequency
Date: Fri, 16 Apr 1999 19:18:51 -0500

VX-5R Expanded frequency

Remove the battery pack, beneath where the pack was, is a black cover
(heavy duty paper) it's just stuck and is removable to install the
optional barometer/temperature module.

Remove this and you'll see 8 solder pads, for some reason some have 3
pads bridged, in my case there were 4 bridged. In either case unsolder
the 5th pad counting right to left. Do a full reset, the HT is now
open.

 This worked fine on my VX-5R, but you are on your own.

K9UO

----------------------------------------------------------------

Dear Fellow HAMsters,

I just traded my FT-51 for the tri-band VX5. This radio is a marvel. I
like the advanced features like selecting the receive mode (narrow,
wide or am). Anyways, this radio is locked up pretty well if no
modification has been done. I found some mods on the internet but all
of them were the MARS/CAP mod. So, I decided to experiment with my
radio and find the full mod. As usual, yaesu was kind enough to provide
us with a schematic diagram of the radio. I glanced at the schematic
and after finding the section regarding the jumpers on the back of the
radio, it was quite obvious what needed to be done. First, take the
battery out. In the upper half of the battery compartment, there is a
black piece of paper covering the radios circuitry. Remove it by
lifting it from the side with your fingernail or flat-head etc...DO NOT
THROW IT AWAY.  In case you're wondering why there is a hole in your
radio, its for the altimeter/barometer gadget you can add to your
radio. After removing the black piece of paper, you will see 8 solder
pads going across the bottom. On my radio, the middle two solder pads
were shorted. If you unsolder the fourth solder pad counting from the
left, you will do the MARS/CAP mod. If you unsolder all of the pads,
you will open up your radio. Now I must say that the full mod on this
radio isnt a FULL mod - its nothing like the FT-51. Unfortunately, the
radio is somewhat handicapped by the microprocessor and there is
nothing you can do(unless you plan on replacing the microprocessor).
When I did the full mod on my FT-51, it could receive almost everything
(fm radio was garbled because of narrow bandwidth) and it could
transmit on a whole range of frequencies including 900 MHz. This isnt
the case with the VX5. In fact, you cant even enter certain
frequencies. If you enter lets say 35 MHz, the radio will beep and it
will return to your previous entry. Also, the radio skips over 868-890
which prevents you from listening to cell phones.

Anyways, the FT-51 was a sweet radio...too bad too sad!!

At least you can listen to radio, shortwave, and tv on the VX5. OH,
one interesting thing - NOT that I did it - but, you can transmit
on CBS (59.7 MHz) and if you're close enough to the TV antenna you
can hear your voice on the TV.

-hrach
KF6PEM

P.S. Here is a list of exactly what you can receive and transmit. 

RX:
.53-16
48-728
800-999

TX:
48-66
108-222
305-577

P.S. #2
When you try to transmit on the frequencies not listed above, the
radio gives a TX error. Now this might be good news, because this
means that the radio is still somewhat locked and that the TX error
is not because the radio is incapable of transmitting. Maybe there
is another modification which can be done to allow this
transmission. If anybody finds out, please email me at
hrachs@ucla.edu

P.S. #3 
Please be careful when modifying your radio. Although this mod
should be fine with all VX5's, your's might be different! Also,
make sure you dont leave any extra solder in the radio. Little bits
can splatter here and there and to your luck, it might land on the
pins of the microprocessor. Anyways, I better wrap this up - 7 am
its almost bedtime. Have fun and DONT transmit illegaly.

-hrach