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Re: AO-27 and MIR on an HT?



Hi Jeff, Jimmy and others,

At 02:38 PM 3/18/99 -0600 :
>On Thu, 18 Mar 1999 12:04:15 -0700, Randolph Kohlwey
<kohlwey@xmission.com> wrote:
>
>> Working AO-27 with a rubber duck is not easy!
>
>Hiya Randy! It's not the hardest thing in the world to do, it just takes a
>bit of practice.

I was referring to the short (under 10") rubber ducks that come with the
HTs I agree it does take practice.

For Jimmy (WA4ILO) just peak the receive signal and do not worry about the
transmit signal.  What peaks the signal for one part of the pass is not the
same as it takes for other parts.  Using a reflector, or pointing at the
ground, turning the HT upside down are all things that can work
one time or another.

If you take your HT away from the cities (RF noise centers), add a preamp, and
use a 4 or more element yagi which you point and twist to peak the signal you
will have full quieting signal as long as the satellite is line of sight.

Getting into the satellite can be done with a short rubber duck and low power
only if given a chance by the higher power stations. Your HT and rubber duck
will lose out to a mobile and quarterwave magmount antenna which will lose out
to an 5 watt HT with a 3 element yagi which will lose out to the 25 watt OSCAR
station using a 20 element cross yagi which will lose out to the EME station!

The fact that stations are getting in without hearing the bird shows that many
of the high power stations are leaving room for those with low power to get
in.
It still helps to try during the week when not as may stations are on.

>> Those who do work AO-27 with a HT and a rubber duck only can work a small
>> part of the pass. Most also use a longer (approx 17") duck.
>
>On a 'good' 15 minute pass, I can usually get into and/or hear the bird for
>about 9 or 10 minutes out of the 15. I use the MFJ-1715S on a Yaesu FT50.

The 1715S is a 1/2 wave on 70cm. MFJ claims 2.15 dBi gain. It is not one
of the "rubber attenuator" antennas. At my location the good passes happen
once per every other day.

>> can not hear it!  People try to call back to them but then give up and
>> start to ignore anyone calling CQ.
>
>Yup.... I heard the CQ'ing yesterday and today the gentleman wasn't calling
>CQ but giving out his call, many were calling him, but the poor sould
>apparently couldn't hear us. 

There have been stations in WA, AZ, LA, and AR that also seemed to not hear
the satellite.
 
> I have to admit, that with my whip antenna and
>the associated background noise, that sometimes I can't always copy the
>calls either, but that is the downside to a small antenna as compared to the
>Arrow.

Even with a yagi background noise can get you in the city depending on your
radio.

Good luck to all those new people trying. I am still trying to work 60 more
US mainland grid square on satellite. To see which grid squares I am after
check

http://www.xmission.com/~kohlwey/

If you would like more help please send E-mail to n7sfi@amsat.org and let
me know what you are trying to work the satellite with. 

73, Randy N7SFI 

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