At 04:28 PM 2/6/2009, Rocky Jones wrote:
Bob...Your "rant" strikes me as pretty close to right on the money. I read the missive in the latest journal about 3.3 and 5.6 ghz links and thought "thats nice, It will never happen".
A baseline requrement for ANY Amateur satellites should be that they work on frequencies and modulation methods which are consistent with radios that are already commercially manufactured for the bands in question...or can use some very easily (think the MDS converters) commercial gear for other services.
The instant the "bird" is designed with some type of radio in mind that does not exist now and is limited to that bird...then the entire adventure is nice but has little practical value.
Why on earth is the AMSAT community wasting time on a design which requires a ground station that is (by the latest Amsat Journal) "beyond the scope of most hams". Instead of spending time working on making an 'acp capable earth station within the reach of most radio amateurs".
Because if the equipment has little value beyond a satellite which could do an Oscar 40 at any time how many are going to shell out the money?
I dont have a clue why the AMSAT design folks seem to think that it isnecessary to drive up into the microwave frequencies. They never seem to answer the question why a 2meter 70cm translator is not a good solution...and the one that we really need.
Meanwhile AO-7 flies on.
Robert WB5MZO life member
Well, there are a few reasons: 1- 2m & 70cm antennas are large and it takes a large satellite to support them 2- Microwave antennas are physically smaller and yet will provide more gain 3- Microwave frequencies are quieter (low sky noise) so they work better with low noise receivers; some mw freqs. are less impacted by interference and/or pirate stations.
When such a mw satellite can be launched, many sources of equipment will surface. Downeast Microwave and Kuhne Electronics will come out with equipment when there is a market for them.
73, Ed - KL7UW