I am looking for any ideas or your thoughts on what would be the safe or
maximum operating temperature of a HF amplifier in rtty operation. My
setup here is a FT5000 driving an Alpha 86 to about 1200 watts on
rtty.... it will do considerably more on cw/ssb and rtty but I felt that
I should limit it on rtty. What started all this is that after about 20
years of just sitting up on the shelf doing it's thing, I decided to
take the 86 apart and give it's internals a good cleaning. Sure enough,
the dust bunnies had been doing their thing. Gave it a good cleaning but
when i went to put it back together i noticed that on the back panel
where the air enters the amp there was a pre-made place to install a
fan. I put a 115 v fan to push air into the amp which goes past the
transformer then into the fan below the tubes and then out the top thru
the tube shields. On top over the vent holes I built a Styrofoam box
with two fans to help pull the air out. Sorta a push-me-pull setup. I
bought a couple of digital thermometers with sensors. I placed the probe
in the airstream coming out of the amp over the fans in the Styrofoam
box and the other the air coming out of the 5000. This is where it got
interesting. On rtty when running the 5000 would get up to about 103 deg
F. from a resting temp of 79 deg. The amp would go from 90 deg up to a
high of 155 deg which sorta made me nervous. I asked my wife if eggs
would fry at 155 and she said probably! SO, do you guys monitor your
amp's temperature and what do you all think is save? Sorry to be so long
winded but I am curious! thanks and 73's Cort K4WI
_______________________________________________
RTTY mailing list
RTTY@contesting.com
http://lists.contesting.com/mailman/listinfo/rtty
|