Lyle Johnson wrote:
Robert McGwier wrote:
Thank you Jim.
ACP?
Advanced Communications Package (to be read: Hambly Marketing Firm, Inc. does not want us calling it Digital).
On L band we need the SDX pick off, the ACP pick off, and the command receiver pick off using a single antenna and any LNA.
By "the command receiver" do you mean a fixed frequency demodulator output for the IHU3?
Yes. A fixed frequency separate input not in the passband. I can hear James Miller in my head : "We shan't have the punters confiscating the command channel".
I discussed some of these ideas with Eric, N7CL, at the TAPR meeting. Eric is very good at antenna system design, did S band stuff for us at MMS and does this sort of thing now for DoD.
Anyway, he suggested we consider Vivaldi's rather than patches. We used Vivaldi's on our trucks at S Band and they work well, are trivial to fabricate (a piece of PC board - I know, radiation, but it is the concept I am wanting us to consider). They are well behaved and have very little coupling to adjacent antennas. I'm not an antenna guy, but you might want to consider the Vivaldi and/or communicate with Eric.
I don't know what a Vivaldi is but I will find out.
Lyle
Bob N4HY