[amsat-bb] Re: SO-50 pass over FN42 at 12:25a local / 0525Z
cdanis at gmail.com
Fri Nov 12 19:19:31 PST 2010
First of all: thanks to everyone who replied, on-list or off, for all the
helpful comments, kind welcomes, and offers for skeds. What a great group!
Early yesterday evening I listened for a pass of AO-51 and then another one
of the FM birds, forget which. (I had only planned on the first, but the
second came overhead almost immediately afterwards while I was still
outside.) Again, didn't hear anything. I had to give up on working sats
for the day after that; it was time for my weekly poker group.
Tonight I got home from work too late for any passes (well, at least ones
>12 degrees of elevation). But I noticed a few things:
* the SWR of the 70cm section was really high. I don't have any absolute
measurements -- the only SWR "meter" I have good at 70cm is the one built in
to the FT817ND -- but it was practically full scale.
* occasionally it jumped down and then back up if I shook the antenna.
So I desoldered the coax. Then I noticed I hadn't gotten the dimensions of
the driven element quite right -- I had bent the brass rod into a tighter
corner than WA5VJB specifies -- about 3/4" instead of 1". So I bent and
un-bent and re-bent things for a while until I wound up much closer to 1".
After I re-soldered, I'm now seeing 0 bars of SWR on the '817 in the
vicinity of 435MHz. Hopefully this was the issue, and not just *a* issue...
My full setup is:
FT817ND with internal battery
poorly-constructed WA5VJB yagi, 2el on 2m, 4el on 70cm, elements made of
brass hobby rod and each band mounted perpendicular (Arrow-style)
no diplexer, just using both antenna ports on the 817. (May soon try 817+HT
on an Android phone: HamSatDroid for tracking, Compass app, and Voice
vy 73! and thanks again!
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