"VE2CJW" wrote in
:

In fact, I found out that I can hit the repeater sometimes if I let
the carrier run for at least 5 seconds. I did reach it this afternoon
every time I tried but can't reach it tonight. It is as if not enough
power is reaching the repeater, probably because of distortion caused
by the large condos in the path, that would explain the long time
needed for the repeater to react to my signal. The antenna I am using
is a Quantum QT-6A dual band with 6 db of gain on 2 meters. My coax is
60 feet of RG-8X mini foam ( I think this is too small ) and the radio
is a Kenwood TM-G707A with 50 watts out on 2 meters. The repeater does
not use a tone and is on a mountain at a height of about 1000 feet, it
is 24.5 miles from here and I am 60 feet above sea level. The SWR was
measured with a meter that is supposed to be unreliable on 2 meters so
I don't trust the reading, anyway, my radio seems to find the antenna
acceptable. The thing that proves that my setup is working right is
that I can reach a couple of repeaters that are more than 70 miles
from here but not on the same heading as the problematic one. I think
I will get my antenna higher and maybe move it a few feet from where
it is. Thanks for your help and suggestions guys, it is much
appreciated.

VE2CJW, Mike.

"Ralph Mowery" a écrit dans le message de
news: . ..

"VE2CJW" wrote in message
...
I can hear the repeater very well, in fact, it comes in at S9+ all
the time. I noticed that my SWR is around 2.5, I wonder what can
cause this.

Mike.


If the repeater is S9+ on your receiver, unless the repeater is
runing very high power (300 watts +)
you should be able to hit it with a few watts. Sounds as if you need
to take your rig to another place and see if you can hit the repeater
at all. Maybe the repeater needs a subaudio tone to activate it and
you do not have it programmed in ?
You did not say what kind or how much coax you have between the rig
and the antenna. A SWR of 2.5 seems way too much. If you had about
100 feet (30 meters) of rg-8 and a very bad antenna, the swr would
not be too much higher.

2.5 to 1 measured at the transceiver is an enormous SWR. If it were
INFINITE at the antenna end, you'd still only get 3.2 to 1 or so at the
end of 60 feet of RG8X. Replacing that coax with LMR400 or, better yet,
heliax would, the problem is with the antenna, give you a much higher
SWR.

The trick is to find some way to measure the SWR at the antenna. If it
is atrociously high, then you have an antenna problem (something is
broken or not connected properly). Measuring SWR at the transceiver on
VHF is almost useles unless the coax run is very short or very low loss.

60 feet of RG8X will only transmit about 53 percent of your signal
anyway. The rest goes to heating the coax. If the SWR at the
transceiver end is 2.5, it's probably well over 10 at the antenna, which
means you're probably not getting more than 1% of your folded back signal
out into space.

If it was mine, I'd bring the antenna down and test it at ground level
until I got it taking power properly. If you can borrow an analyzer,
even an MFJ 259b and measure the antenna directly at its terminal, that
will help you see what the antenna is doing.

--
Dave Oldridge+
ICQ 1800667