See if the PA transistors nuts, bolts and screws are all sung on the heat
sink...I had a Paragon that had loose hardware...due to running a lot of
rtty.
--------------------------------------------------
From: "Mike Bryce" <prosolar@sssnet.com>
Sent: Thursday, February 16, 2012 7:23 AM
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Subject: Re: [TenTec] Low (to no) Power Out Omni D--han'nt given up yet
> Rick,
>
> Scott, is right.
>
> Although you are getting two watts from the PA, you need to have more from
> the LLD.
>
> The fact that you're not drawing current indicates you're not making the
> PA work. If you were drawing current and nothing was coming out, then
> you'd have a shorted transistor or two.
>
> It is still possible that you have a failure in the PA, but those
> transistors are a bear to get to.
>
> When an solid state PA is assembled, it's built from the pcb upward like a
> building is assembled from the ground up. If one or both of the
> transistors are bad, then you have to un-assemble the entire PA to get to
> the bottom transistors. It's labor intensive and after you're done, right
> now it's a crap shoot as to wether or not that's the problem.
>
>
> This weekend I'll pull one of my Omnis out of the pile and measure the LLD
> power into a 50 ohm load and I'll see about getting some wave form photos
> from the scope,
>
>
> Now, I know this is a long shot, but if you had someone near by with a
> defunct triton 4 the pa is damn near the same as in your omni, a quick
> swap would tell you volumes.
>
> Or...
>
> do you own a qrp rig?
>
> disconnect the omni's PA from the LLD and inject 3-6 watts into it from
> the qrp rig. Key the omni and you should see 30 to 60ish watts. (make sure
> you're one the same band!)
>
> what you did would be to use the qrp transceiver as the LLD and allow the
> PA to to its thing. Yeah, there's all kinds of impedances mismatches, but
> it will work.
>
> Mike, wb8vge
>
>
> On Feb 16, 2012, at 9:53 AM, Rick - DJ0IP / NJ0IP wrote:
>
>> Scott, rather than second guessing, or waiting for Paul to read this
>> thread
>> by coincidence and offer suggestions, why don't you compose a list of
>> specific questions and call or email them to Ten-Tec.
>>
>
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>
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