Adi, I just did a temperature vs time study on the T83 and T44 Mitreks with and without forced air cooling. If you send me a private email to [EMAIL PROTECTED], I will send you the temp curves and analysis by attached email.
Bottom line, even at 50 watts, the T83 reached 150 degrees PA temp without cooling after 6 min keydown. Two 3 inch fans - 1 cut in the cover to fit over the PA, the other cut through the case and placed on the right side to exhaust air, kept the T83 under 100 degrees even at 100 watts. Failure of 1 fan did not appreciably increase PA temp. 73, John N4SJW --- In [email protected], Adi Linden <[EMAIL PROTECTED]> wrote: > Hi, > > I've tuned up a 146-174MHz Mitrek to operate on 147.315/147.915 MHz. The > T83 model puts out a solid 100W and draws about 25A at 13.8V. I figured > that for repeater duty I should be able to run 100% duty cycle with a > reduced power output of 50W and some forced air cooling. > > I've read somewhere that the T83 PA creates spurs when the power is turned > down too far. I've been monitoring the PA output on a spectrum analyzer > while adjusting power levels. Even at 10W out I don't see any changes in > the spectrum display (other than the changed output level at 147.315MHz). > > What should I be looking for in particular? > > Adi > -- > Adi Linden | va3adi | [EMAIL PROTECTED] | http://adis.ca > +-----------------------------------------------------------------+ > IRLP Node 2590 in Sioux Lookout, Ontario Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
