[ICOM] Re: IC746 Reduced Output

[gfiber at comcast.net]

I am sure you know already but do Remember those fuses are the only protection for the PA section. The internal fuse does not protect the PA at all as the PA is directly connected to the power supply.

Also the negative fuse protects against reverse polarity so long as the internal diode is intact.

I remember one time I was working at a marine radio shop. Right in front of the customer I connected up his radio backwards, no fuse in the power supply leads I was using. I really let the smoke out of the reverse polarity diode. I was very lucky no other damage was caused. It was pretty embarrassing for sure.

Gary K8IZ
 -------------- Original message ----------------------
From: Mike <k4gmh at arrl.net>
> Thanks to all who provided input to solving the problem.  Turned out 
> the fuse holders were both getting warm with less than a minute of 
> keydown.  This was after opening the holders, removing the fuses, 
> replacing the fuses and closing the holders.
> 
> Now the fuse holders have been removed and wires from the power 
> supply go directly to the connector on that mates with the one on the 746.
> 
> At 10:32 PM 2/26/2006, Mike wrote:
> >Hello,
> >
> >Recently I've noticed the output on my Icom 746 is around 70 W.  The 
> >reduction has been slowly going down, ~3 mo. as best that I can 
> >remember.   The output is the same for CW or SSB , with a single tone.
> >
> >The power supply is still putting out 13.19 volts to the radio under 
> >full load, 13.48 under no load.
> >
> >Any ideas on what can be done to get the radio back up to full output?
> >
> >         73,
> >         Mike, K4GMH
> 
>          73,
>          Mike, K4GMH 
> ----
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