In a message dated 15/01/2008 16:00:01 GMT Standard Time,
microwaves@... writes:
Sorry,
but I can't agree with you there Mike!!
RF talkback, IMHO, is ESSENTIAL
when out portable. KST is a form of talkback. Certainly for 10GHz you
can't point the antenna, call CQ, and expect to get replies (except during
rainscatter conditions). For backpack portable, RF talkback (ie 2m ssb
144.175MHz) is the preferred method. Unfortunately the home stations seem
to have turned their backs on us portables and many use KST exclusively so
we dont know if they are active. It's their loss as they won't be able to
get in touch with me if I'm in a rare square with my backpack portable
gear:-) Only those with RF talkback will be able do that.
It IS
possible to use KST from a vehicle of course but some portables are
finding that it is a real bind using a laptop(wind, rain, bright sunlight,
etc), especially if they operate outside the car, at a tripod. It's much
easier for me in my van but I often find the GPRS telephone link (needed
for the /P internet connection) is unreliable. There are many summits
where you cannot get a decent mobile phone signal. I have to carry three
separate SIM cards to make sure I can access at least one network and then
it's not always certain I'll get one. I can't see a way out, if
backpacking with microwaves, unless one buys one of these fancy mobile
phones with a minute internet screen and browser on it.
I think Richard
could use the second VFO on his FT817 on 2m talkback and then use a BNC
coax switch to change the FT817 from feeding his transverter to feeding a
small portable 2m beam... his SOTA beam of course! 5 watts of 144MHz ssb
from an FT817, on a summit location, should get him out over a couple of
100km or so quite nicely ... certainly enough distance to be within the
capabilities of his DB6NT system.
Back in the 80s, I frequently carried
30lbs or so(wideband TX/RX, 7AH Yuasa battery, 18" dish, short 4 ft mast
for dish, 12ft mast for 3 el yagi, IC202S 2m talkback rig, plus food, wet
weather gear, 1st Aid kit etc)or so up Scottish and Welsh mountains to do
10GHz portable. I don't think a barefoot DB6NT would weight anymore than
my old wideband gear and the 817 is much lighter than a 202.
>
Certainly in the days of QRP WBFM (<10/15mW), with it's ill-defined
> stability and frequency, talkback was necessary, but I don't think it
is now
Believe me, it definitely is necessary!
> ....There
may be those who disagree, but I'll take the
flak! ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
You
did ask!
It was said a bit tongue in cheek, Peter, and I did say I'd take the flak!
I guess that Richard was thinking not so much of the weight of the gear,
but more of the unweildyness of the poles and (2m) antenna. Of course there is a
BIG difference between the backpack portable work we used to do, and the kind of
"car-borne" setup which is commonplace these days - and, of course "summiting"
is somewhat different again....
In my physically active days I thought nothing of hiking 80-100lbs. of
caving and camping gear miles up hill and down dale almost every weekend -
so top-heavy on an old Bergen framed rucksac (yes, ex-Govt!) that if you went
over, it was difficult to get up again - but then I was in my twenties and
early thirties! Blood Yell, nearly 50 years ago!!
If, as I think it is, many SOTA microwave contacts would be pre-arranged
(not "chance"), just like we used to do in the forerunner of the NewsLetter, in
which case (a.) there is much less need for talkback and (b.) there may be less
need for *power* and antenna gain on the talkback band?
You are, however quite right - Richard might be well advised to
consider using the dual VFO in the 817 plus coaxial c/o for talkback and
maybe a SOTA compact beam? After all, the 2m QRP Backpacker contests seem to
"net" their participants some fairly respectable QSOs without using large
beams/masts and with little power.
Mea culpa! Take talkback certainly, but keep it within sensible limits if a
*true* backpacker, not car/P! And use it properly!
Regards, Mike, G3PFR
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