This thread proves one thing: Comments recieved by those not familiar with
this amp or those who have not been into this model or looked at the
"Roadmap" were just giving an educated guess of the problem...Makes sense
thou,corrosion on connectors &rf don`t like each other. Practical technical
experiance won out over engineering minds this time...Ho-Hum...Jim K7RDX..
----- Original Message -----
From: "Jim Brown" <jim@audiosystemsgroup.com>
To: <amps@contesting.com>
Sent: Monday, September 25, 2006 9:29 AM
Subject: Re: [Amps] Titan 425 Reflected Power
> On Mon, 25 Sep 2006 07:22:53 -0700, Michael Tope wrote:
>
> >Are you sure that you have done due diligence twiddling the
> >amplifier load and tune controls with a zero reflected power
> >reading on the external Bird meter (higher VSWR reading on
> >Titan meter).
>
> Thanks for all the ideas, both on and off list. I've got some work
> to do when I find some hours. One of the most interesting
> responses was this one from N7KA. The symptoms match mine exactly
> on both of the two Titans I own, and I also bought new tubes for
> the same reason he did.
>
> >I purchased a used 425 and experienced low output and if I
> >increased drive output might go up but grid current went way up.
>
> >Here is what was found to be the problem. The coasx going into
> >and out of the input low pass filter board uses tho9se el-cheapo
> >japanese connectors. found the center conductor of the miniture
> >coax is used a "plug-in" pin into the pcb of he input filter.
> >Guess over time corrosion got the best of it. I soldered both the
> >input and output coax lines (center conductor) to the pc board
> >and mhy problem went away: 1500W out without exceeding the max
> >grid current.
> >
> >I purchased a pair of new tubes, 3CPX800A7 tubes because I
> >thought tubes were flat: NOPE. Now I have spare set of tubes,
> >NOT FOR SALE.
>
> 73,
>
> Jim Brown K9YC
>
>
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