[K4RY] IC-207H RF Power Output

[WB4LNM at aol.com]

Thanks for all who attended todays AUARC meeting.
 
A little more on the subject of the IC0207H with no 2 meter output  power.  
I've looked at the service manual and that radio uses the SC-1091 /  SAV-17 
power amplifier module.  These parts are infamous for failure due to  heat 
cycling.  The power module is made on a ceramic block and if not  connected 
to the heat sink properly, flexes and cracks one of the gold traces on  the 
module.  I have repaired one or two of these by taking the cover off  the 
module and carefully jumpering the offending crack.  It doesn't always  work, 
and there is no guarantee that it will be a long term fix, but it is worth  
a shot before plunking down $80 plus shipping for a new module from RF  
parts.
 
The thing that had me baffled is that I was able to hear the transceiver on 
 my HT AND the IC-207 showed a full relative RF power output reading on its 
front  panel 'meter'.  I guess it is like my Kenwood TM-742 which really 
doesn't  sample the RF power output, it just has it's microprocessor drive the 
meter  symbols to full scale.  I had that happen when I lost the DC drive  
transistor in the '742 and yet it still showed full RF output when there was 
 none.  I should have remembered that chintzy designers do that sort of  
thing.  
 
In any case, there may be a technical solution to this which we will get  
around to.  
 
Please put Tuesday, 17 November, 12:30, Broun 411 on your calendar for out  
next get-together.  BBQ will be provided.  I'll ask for a headcount as  the 
date nears.  
 
73
 
John...
WB4LNM
 
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