[Date Prev][Date Next][Thread Prev][Thread Next] - [Date Index][Thread Index][Author Index]

Re: How much power?

On 3/9/06, Tim Tapio <tim@timtapio.com> wrote:
> I just attempted my first contact on Echo this evening.
> Do I need to use the full 5 watts to access or was I just holding
> experiencing jitters and probably on the wrong tone?

Hi Tim,

Congratulations on getting into amateur satellites.  That brings back
some memories. ;-)

The FM transponder on Echo will only accept one signal at a time, so
you likely just didn't capture the receiver.  Right now Echo is in
high power mode and it seems that more people are trying to use it
than usual.  I have noticed that it has become difficult to get in
with my TH-D7 and arrow antenna since it went into high power mode. 
Usually I have no problem.  I transmit with 5W.  When it goes back
into standard power mode, it is likely that less stations will be
trying to use the bird so your chances will improve.

You should give SO-50 and AO-27 a try.  Both are still operational and
work in the same fashion as Echo.  AO-27 has a low power downlink, but
with the arrow antenna, you should not have a problem receiving once
you find it in the sky.  SO-50 and AO-27 also tend to be less crowded
than Echo and are easier for learning.  The only trick with SO-50 is
that if it is not on when it comes over, you have to turn on the
transponder by transmitting a tone of 74.4 on the uplink.  Then switch
your tone back to 67.0 to make your contacts.  There have been times
that I have heard only two or three stations on SO-50, so it is
definitely a good bird to practice on.

One other thing I would suggest is not to tripod mount the antenna,
but rather hold it in your hand.  You not only need to point at the
satellite, but you will find that you need to twist the antenna to
match to polarity and max out your receive signal.  I have tried
mounting it to a tripod and had a hard time making contacts.  Handheld
it is much easier to adjust once you get used to it.  You'll figure
out the HT/Arrow dance in no time. ;-)

Have fun!

A.J. Farmer, AJ3U
Sent via amsat-bb@amsat.org. Opinions expressed are those of the author.
Not an AMSAT member? Join now to support the amateur satellite program!
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org