[TenTec] Titan II Mods

[Roy Koeppe]

Hello All,

In case others are frustrated with their Titan II's, I offer them this
FYI:

My new Xmas present to myself had a fan which sounded like a helicopter
and even shook the table. I cured that entirely objectionable problem by
constructing a pressurized wooden platform for the amp to sit upon. The
one inch thick material is 5 1/2 inches high, thus also elevating the
amp to a more desirable height for viewing its meters. The top and
bottom edges are lined with thick felt strips for an air tight fit. A 10
foot long clothes dryer hose (4" dia.) runs from this base to a cubby
hole closet which our house builder conveniently provided under a short
stairwell. In there is a remote squirrel cage blower, Fasco cat. no.
F2-2440, ordered online from www.herbach.com. It's made in USA and its
dynamic pressure and volume exceed that of original Titan II's fan. Its
round outlet flange snuggly fits directly into the clothes dryer hose. I
glued it in there with Shoo Goo. The blower is well balanced, smooth and
quiet with no radio noise. The original fan was removed and set aside.
Air enters through the original fan's bottom hole. The amp's rear feet
were removed. This remote blower concept is not mine--Collins used it in
their model AM-1 if my memory serves me right. The Titan II is now
virtually silent in operation. The slight hiss of air exhausting from
the jug is subdued by placing a chimney-like muffler over the exhaust
port. It is big enough to have no restriction of air flow and is lined
inside with sound absorbing material. Both the platform base and the
chimney muffler are painted Ten-Tec gray.

Now for the second objectionable problem. Two ceramic disc caps are
switched in parallel with the variable loading cap during 80M operation.
These caps are unbelievably small and cheap. (No padder is used for the
plate tuning cap on 80M, thank goodness). They drift like crazy during a
transmission, being manifested as sagging output and lowering screen
current, often down to the point of negative screen current. All this
concerns CW operation at full 1500 watts out, into a perfect 50 ohm load
(Nye Viking tuner). I have not tested it on SSB.

The cure for this second dilemma was to install a single 320 pF xmitting
mica, rated 2.5 A @ 5 KV in their place. I "remote located" the new cap,
placing it near the fil (heater) xmfr. A short piece of good quality RG
58 connects the cap to the bandswitch. The shield is grounded at both
ends. The job was performed in such a manner that the amp can be easily
and speedily restored to original for you know what reason. The original
two caps' total value were twice that of the new the 320 pF value,
causing the loading control to run more than half way open. This new,
lower value allows the variable loading cap's plates to operate in a
more fully meshed position (number 7 when operating on 3522 kHz). Now
both the plate tuning and loading dials read approximately the same;
plate remaining at  number 8 on 3522 kHz. This new loading setting
allows for more circulating current in the variable loading cap and less
in the padder.

The improved system has been tested with excellent results. Now the
readings remain perfectly solid at all times. I don't presently use
160M. But I'm sure a similarly awful situation exists there, where both
ceramic plate tuning and plate loading padders are switched in!

73,   Roy      K6XK         Iowa          Outback









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