[Icom] Mods for ICOM 756 PROII

[Ray V.]

I can verify the gradual power output degradation between 5.2 and 
5.999mhz. I made the MARS mod to get to various MARS 5mhz channels in 
that range from near the proposed 60 meter band thru the very high end 
of 5mhz and must say that the 756ProII is NOT a good choice if you 
anticipate wanting to work 60 meters barefoot if it ever becomes 
available to hams. At first I thought it was just my ProII but I have 
had many comments agreeing that it does not provide full output in that 
range and NO comments from anyone who said theirs works fine with full 
output from 5.2 to 5.999. That it has something to do with the bandpass 
filters seems clear because 5.999mhz (into a dummy load of course) has 
barely 10 watts output, but change to 6.000 when the next bandpass 
filter is switched in and power jumps right back to full output.

Fortunately most of my MARS operation on the 5.2-5.999mhz range is 
digital so the low power restriction doesn't seem to be too bad, but on 
SSB nets, I have to go back to my old TS-940S which works just fine in 
that range.

My IC-706MkII also works fine in that range, it's just something Icom 
did to the 756ProII that restricts its power output in the 5.2 to 
5.999mhz range.

As Bill says, the mod is not for the faint of heart if you can't handle 
  unsoldering SMT component diodes about the size of the head of a pin.

73, Ray  W2EC

Bill Tarkington wrote:

> Hi Ken:  I too own the Pro2. Only mod I am aware of is the MARS mod for both
> US and European units. This mod calls for the removal of specified diodes to
> open up the transmit of the Pro2.  It is already wide open for Rx, but not
> -----------snip----------