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

initial reflections on AO-40 24GHz

Hi Folks, 

I visited again Michael's OH2AUE amazing web-site (tnx Michael) and heard the 
K band signals from AO-40, wow!!!!
Next and as part of my 24GHz endeavour I went trough my microwave books 
(basically those from ARRL and RSGB) and start digesting info on the topic. 
Also visited some other repected sites in the net (e.g.. W1GHZ and others). 

Based on this preliminary review of information below are my initial 
reflections on AO-40 24GHz. I am writing this because I would like to share 
them with you, so you can challenge, agree or disagree and most important 
contribute with info and your knowledge and suggestions on how to walk the 
path from 2.4 to 24.

1. 24GHz is going to be a real challenge for those of us that are microwave 
illiterate (I guess a bunch of us here at the bb). BTW, I am refering to 
24GHz narrowband (SSB, CW) rquired for AO-40 vs wide band FM (WBFM). Yes, I 
know we have been doing 2.4 GHz Rx for a while and that technically speaking 
this is microwaves, but from X band up things are very different (that's why 
I consider myself illiterate).

2. At this point I really don't know how though the learning curve is from 
2.4 to 24 without stopping at X and WBFM. Theory is not that though, but form 
the practical point of view it does not seem easy to me (even going the way 
as per #4 below).  I was expecting to cut my teeth on the high freq microwave 
bands with X band on AO-40 and move from there to K, but it seems it may not 
be the case. It also seems to me that X band would be easier, more fun (and 
cheaper) than K mainly because of the availability of a variety of equipment 
from different sources (surplus included). The later takes me to point #3

3. There is not much 24GHz gear out there (consumer's worst enemy, no 
choice). I have not been able to identify sources of equipment other than 
Khune (DB6NT), and wish we had some other options, do we?

4. Yes, you could do almost one stop shop (willing to spend some real money 
1K3 DM in EU, $xxxx in US) and get a beautiful state-of-the-art DB6NT preamp, 
mixer, LO, etc... another stop (and toll) to get a 24GHz band pass filter, 
horn and antenna and assemble all together. However, I wonder how much fun 
and learning is in there (am I wrong?). Please do not misunderstand me, 
probably this would be my ultimate goal but would like to walk the path if 
possible (I really love junk ;-)). As an example of this I had much more fun 
modifying and improving my TSI AIDC 3733 D/C (now a great performer, tnx to 
Bob) than installing my SSB UEK2000 in the antenna mast.

5. Even having and willing to spend the money, some items may be difficult to 
very difficult to get (e.g. RHCP, a WG band pass filter, etc)

6. All the previous makes 24GHz a very attractive proposal

7. We could discuss this also in Atlanta, would be very nice to have 
somethign like a working breakfast (don't see much space in the program right 
now) in which some 24GHz experts would enlight the illiterate crowd.

Best 73 de antonio, kc2hax/ea4le
<A HREF="http://www.qsl.net/kc2hax";>http://www.qsl.net/kc2hax</A>
Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org