Wednesday, 2 November 2011

Birds in Space....de MW0MJB


I've long  found the ham satellite part of our hobby fascinating, but never really looked into it properly, ....that was until last November.

This time last year I decided to make the effort and work some of  those "birds".



I already had an FT736r but no real satellite antenna system.


I did have a 5 element Jaybeam dismantled in the attic, and the best part of a 70cm beam, kindly given to me by local fellow ham Tom MW0CXW. 

The 70cm antenna was also a Jaybeam, I think it started life  as a 12 element, but I was only able to salvage 9 elements.

Still I was hopeful of the results it would give.


I had a cheap old laptop which was good enough to run the excellent satellite software  Orbitron...this software is perfect for tracking the ham sats..it never let me down once...


After buying a small rotator from another local ham I was ready to connect everything together.

First contact was via AO51, an FM contact to ES5QA ....the satellite was only about 5 degrees above the horizon, but we were able to easily obtain  59 signals both ways.
As AO51 has it's downlink on 70cm,  at least I knew that my salvaged 9 element beam wasn't deaf.....

I have to admit I was putting 15 watts into the 2m beam for this contact, but it didn't take me long to realise that half that amount was more than enough to work the FM sats.

In total between the 6th of November 2010 and the 21st of February 2011 I worked 24 stations through AO51 . Sometimes I could hear what sounded like East European taxi's coming through the satellite,  I thought it best not to try contacting them ...HI..!!



Out of the FM ham satellites available my favourite has to be AO27, that bird has some wonderful ears and my meagre signal (10 watts) was easily heard over the pond into Vermont and Rhode Island.

I made a contact with N1RCN Fletch into Rhode Island. Fletch commented on the QSL  that my signals sounded as if they were next door!.. not bad I thought for 10 watts to a 5 element 2m Jaybeam and a distance of 3101.92 miles.

The contacts on A027 to the East coast of America  were very close the edge of my satellite footprint.
A027 was only some 3 or 4 degrees above the horizon when I had that contact with Fletch N1RCN.

I remember reading the following on one of the AMSAT pages:
Love Those Oceans!

If you're fortunate enough to be operating from a place within, say, a few hundred miles of the coastline, you'll probably find it easier to get into AO-27 and SO-50 with low power when the satellites are out over the ocean than when they're overhead or passing over central North America or Europe. That's because there will be fewer stations within the footprint to compete with you, and most of your competitors will be farther from the satellite than you are so the inverse-square law of signal strengths will work to your advantage.


Where I'm situated in West Wales the coastline is only about 3 miles away, which helped dramatically in working into the USA on the birds. If I timed it right the footprint of AO27 would have my QTH at one end, and the East coast of America at the other. 

Often at my edge of the pass the footprint would only just touch West Wales and the tip of Southern Ireland...

AO7

The best distance pass I had to the states was on the old bird AO7. 

This wonderful old timer, as most of us know has been circling our planet for nearly 37 years. The anniversary of it's launch will be on the 15th of this month. 

And still A07 is able to do it's magic, albeit with reduced capabilities...

Even though it struggles I was able to have a CW contact with Kerry WC7V all the way over in Livingston Montana, Loc: DN45RP a distance of 4,389.10 miles


In total between the 6th of November 2010 and the 21st of February 2011 I worked 15 stations on AO7, all of them on CW, for some reason; or maybe it was the FT736r ( me probably..HI) I wasn't successful on SSB through AO7,  I found it much easier to just use the key. Which I preferred anyway....


VO52 was sometimes difficult to work on SSB, again the CW contacts were much easier..  

It was fun to work VO52, but for me AO7 still holds the edge.

HO68 was a bit disappointing, I expected more contacts on this sat, maybe it didn't like my antenna configuration, both my antennas were on the horizontal, maybe it was my operating practice, but HO68 was very much hit or miss from my QTH..

SO50 and SO67 definitely didn't like my antenna set up. I managed to work through them a couple of times but I knew the problem was down to my polarization. 
I would've had much better luck I guess using an arrow antenna or similar.

FO29 I found really frustrating.... Due to the Doppler Shift on the SSB 70cm downlink I could never get my receive right, or transmit for that matter..HI !!  

Here's the entire list of ham sat contacts for my test between the 6th of November 2010 and the 21st of February 2011:

AO7      15
AO51    24
HO68     7
AO27     8
VO52   10
SO50     2
SO67     1
FO29     1

It would have been nice to have had a few more contacts on AO27 but the satellite often timed out, either half way through a QSO or just as the pass was heading my way...

Never mind... it was all fun anyway....  :0)


I always wanted to try out the ham sats, but I never realised just how addictive they can be. 

Your sitting in the shack listening on 2metres or 70cm and there's no sign of  anybody local on the band , and no Tropo... what do you do?

Simply turn on the computer, run the ham sat prediction software, and guaranteed within 10 minutes one of those ham sat birds will be heading your way... 

Some say it's just repeaters in space..and they're right. But for me every time I hear that faint crackle of voice or Morse coming over the distant horizon, via those said repeaters it brings a smile to my face. 

Long may there be repeaters in space!!!   :0)


I don't have a ham satellite set up at present, other things and work are getting in the way....

But guaranteed the call of the ham sats will be grabbing me one day soon.... 

In the not so distant future I hope...

73 fer now

Mark  MW0MJB

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