Jim....I just had similar problem and to my horror discovered one of the
driver transistors on the low level driver board had never been soldered to
the circuit board as well as a couple of the assocated caps!!! Not a drop of
solder was on the pads, just the leads sticking through the holes.....Not
making this up........U G H!!! I just bought the rig a year or so ago off of
eBay so not sure if this problem bothered previous owners, but can't believe
it didn't show up in the last twenty years (or, however long ago the rig was
manufacturered).
I also found a bad 10k pot on the ALC board that was intermittent (the ones
to align the ALC action), couldn't find a direct replacement so jerry-rigged
a pot on the board until I can locate a proper replacement and this
"stablized" the output.
Hope this helps some........good luck! 73 /ed
>From: "Jim Reid" <jimr.reid@verizon.net>
>To: <tentec@contesting.com>
>Subject: [TenTec] Low Output, Corsair II
>
>Wonder what now. Was sailing along on 40 CW at around
>85 watts out; then it was down to 17 watts!?
>
>Now, best Pout on 40 CW, into a Bird dummy load is about
>30 watts. Drive knob fully CW; ALC knob also full CW. However,
>the ALC light goes OUT after the ALC knob turns much past
>the 2:30 position or so? Occasionally the Pout will get up to
>37 watts. Ic on the CII meter reads 10A at 33 watts into the
>load.
>
>Best Pout on the other bands into the load: 160, 22W;
>80, 22W; 40, 33W; 24W; 20, 24W; 17, 22W; 15, 15W,
>12, 22W; 10, 6W. For whatever use that info might be.
>
>Just 13 months ago I had this unit(561) at TT for check out for low
>Pout. Note which came back with the rig was that they had
>resoldered the low level driver board connections, reset the
>AKC and tested all bands as OK. And this was after the unit
>had been at TT just the month before that when it was completely
>dead! List of fixes came back with the first service; not clear
>which particular one actually brought the 561 back to life.
>
>I suspect the age and the shipping across 5000 miles has had
>something to do with those early problems after I bought the rig
>and had it shipped out here from the East Coast. But don't
>understand how the power can be just fine, and a few minutes
>later be cut more than in half with no movement of the unit on
>the bench.
>
>Oh, oh. That line just gave me an idea; why not slap this
>unit and see what happens. Just did that----and the Pout
>just jumped back up to 78 watts on 40!! So, bopped it again,
>just with my outstretched fingers -- Pout jumps up a bit more
>to 83 watts?? And the Ic is up to about 14 amps.
>
>Obviously something is loose, not quite right inside, hi.
>
>I would prefer NOT to ship this entire unit back to Tennessee
>again, but maybe just the right boards
>
>Any thoughts, suggestion? My vision is not so good, so no way
>I can get in there and resolder any connections, hi! But my
>xyl can if I knew where to aim her!
>
>73, Jim KH7M
>
>
>
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