CPU MODS FOR THE
                           YAESU FT-727R HANDHELD
                            By Mark Huff, WA4DHY

Here are the CPU "modifications" known for the YAESU FT-727R handheld.  As the
one that most are interested in is the extended (out of band) coverage mod,
here's how to "open up" your FT-727R step-by-step.  (NOTE: The following
instructions for extended coverage will work for both the old and new CPU
versions.)

1. Remove the battery pack.

2. Locate the RAM backup switch according to your manual (this will be the 
   switch FARTHEST away from the two small battery terminals).

3. Turn the switch off, count to 5, then turn it back on.

4. Slide the battery pack back onto the handheld.

5. Turn the handheld on. The readout should be entirely blank. If it is not,
   you probably did not wait long enough before turning the switch back ON,
   so repeat the above procedure.  

6. Key in the following on the Keypad:  001111

The rig should now come to life.  You will have to reprogram all the memories,
as well as the repeater splits (shifts) for both bands.  The display will now
cover 100-199, and 400-499 MHz, but it obviously won't work over this entire
range due to the inherent limitations of the circuitry.  Coverage will be
around 139-159, and 420-461 MHz.  Also note that you must enter frequencies
from the second (tens MHz) digit on.  (I.E.  Before the mod, getting to
146.88 MHz meant entering "6880" or "688D".  After the mod you must enter
"46880" or "4688D".)  The reset code, to place the rig back to U.S. ham band
coverage only, is 007777.


ADDITIONAL STUFF

There are additional CPU codes for the FT-727R, which can be used to modify
it's performance in several ways.  Here are all the known codes, and how they
affect the handheld.  They have only been tested (with the exception of
"001111") on the new CPU (late-1987 and later) model of the FT-727R:

001111:  Extended frequency coverage setting.  Will tune 100-199 and 400-499
         MHz, but actual operating coverage is more limited (typically
         139-159 and 420-461 MHz).  Steps available are 5/10 KHz on VHF, and
         12.5/25 KHz on UHF.  Shifts on both bands are empty (0.0) by 
         default and must be reprogrammed.

003333:  Use for this setting is unknown.  Coverage is 144-154 and 430-440
         MHz.  Steps of 10/20 KHz are available on both VHF and UHF. 
         Although coverage goes above 150 MHz, only keyboard entry from the 
         one MHz digit on is available.  On VHF, to go above 149.990 MHz, 
         you must start from the upper reaches of 149 MHz and scan up above 
         150 MHz.  Shift on VHF comes up empty (0.0), but UHF has default 
         shift of 5.0 MHz.

005555:  Possible Region 3 setting.  Turns handheld into the "B1" model.  
         Coverage is 144-148 and 430-440 MHz, with steps of 12.5/25 KHz on 
         both VHF and UHF.  Shifts are 0.6 MHz on VHF, and 7.6 MHz on UHF.

007777:  Standard Region 2 (U.S.A. and Canada) setting.  Makes handheld the 
         "A" model.  Coverage is 144-148 MHz on VHF, and 440-450 MHz on UHF. 
         Frequency steps available are increments of 5/10 KHz on VHF, and 
         12.5/25 KHz on UHF.  Shifts are 0.6 MHz on VHF, and 1.6 MHz on UHF.

009999:  Region 1 (European and African) setting.  Sets handheld to the "B" 
         model.  Coverage is 144-146 MHz on VHF, and 430-440 MHz on UHF. 
         Both the VHF and UHF bands have frequency steps of 12.5/25 KHz.
         Default shifts are 0.6 MHz for VHF, and 1.6 MHz for UHF.

Any of these codes can be entered into the CPU by following steps 1 through 6
on the previous page, substituting the code entered in step 6 with any of the
above codes.  No doubt more codes exist, but these are all that have been
heard of to date.


73,
Mark Huff, WA4DHY