Friends:
Don't know if I'm worried over nothing, or if this
could be a future problem.
Have 3 antennas up now:
a. 40m folded dipole fed with 300 ohm lead up 30 ft.
b. 30m sloper dipole fed with 300 ohm lead up 30 ft.
c. R5 vertical for 20m - 10m
On a & b above get 1:1 swr on whole CW portion of band
using my Tucker-1000 tuner. R5 tunes fb with no tuner.
Here's the rub - using the FT-840 on every band except
30m, (running 5 watts) the rig stays nice and cool. Only
after keying for about 15-20 minutes at 20+ wpm does the
rig's cooling fan kick on for a few seconds.
On 30m, however, after about 3 minutes of keying, the rig's
heatsink gets warm (not burning hot, but warm) and the fan
needs to run. I'm super worried about damaging my finals
before I get to enjoy this rig. How hot is too hot?
Is this a sign that my set-up is inefficient on 30? Even
though the tuner provides a good match to the rig, does
the rig have to "work harder".
BTW - In a & b set-ups, the 300 ohm fed is not longer
than 50 feet.
I know to be sure, I'd need to get an antenna analyser
on this antenna. Any clues would be welcome.
73 de Dave NR3E/5
nr Dallas, TX
qrp-l #25, ARRL
WIMPS: Qs=000 30m=00 17m=00 12m=00 States=00/00/00
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