[amsat-bb] seeking info on AMSAT (any platform) utilization of >2 GHz frequencies

[Mike Seguin]

Back in 2002, AO-40 was running K Band down (24,048 MHz)

G3WDG and I both had K band receivers. Charlie was running a ~10' dish? 
and I had just a 0.5m dish.

Charlie used circular polarization, so his receive signal didn't suffer 
from spin modulation. I was using a linear feed, so the signal would 
fade out for 2-3 secs or so as the polarization shifted from horizontal 
that I was running.

Here's my reception of Charlie's signal - our first successful L/k contact:

https://drive.google.com/file/d/1J_U7GIdrCr7A12XTqYmgs9L4HATyaMOJ/view?usp=sharing

Here's Charlie's audio of me:

https://drive.google.com/file/d/13ffNjzyZcWNwino06wTFQn-5NVBBbmaF/view?usp=sharing

Mike, N1JEZ

On 7/16/2018 6:21 PM, Zach Leffke wrote:
> 
> I think historically there have been some birds that operate in the 
> higher bands.  AO-40 comes to mind with downlinks in multiple microwave 
> bands topping out at 24 GHz (didn't miss a period there...that was 
> twenty four gigahertz, not two point four gigahertz, though AO-40 had 
> that too).   (ref: http://www.ne.jp/asahi/hamradio/je9pel/ao40freq.htm) 
> There may be some others from the Phase 3 era with microwave 
> uplink/downlinks, but I'm not as sure of the history there..
> 
> -Zach, KJ4QLP
> 
> Research Associate
> Aerospace Systems Lab
> Ted & Karyn Hume Center for National Security & Technology
> Virginia Polytechnic Institute & State University
> Work Phone: 540-231-4174
> Cell Phone: 540-808-6305
> 
> On 7/16/2018 5:40 PM, Eric Fort wrote:
>> As one goes up in frequency the Doppler goes up. That said, these 
>> would be great on a geostationary bird or something that moved much 
>> slower than the short Leo passes for most of our satellites. There are 
>> some satellites build and pending launch for amsat phase IV in 
>> geosynchronous orbit. Those launches are not cheap though and rides 
>> are much more difficult to come by. At least a few of the sats 
>> awaiting launches will use the microwave bands you speak of for their 
>> uplink and downlink. The advantage of using that spectrum is multiple 
>> MHZ of passband (think the entirety of all amateur spectrum 6m and 
>> below easily on one transponder 24x7x~365.25 to anyone in the 
>> footprint. It would be nice if amsat would provide better support for 
>> these projects and the teams that work on them.
>>
>> Eric
>>
>>
>>
>> Sent using SMTP.
>>
>>> On Jul 16, 2018, at 5:29 AM, Samudra Haque [TTLLC] 
>>> <sehaque at tekterrain.com> wrote:
>>>
>>> Hi, I am experimenting with RF carriers above 2 GHz in my lab. 
>>> According to FCC and ITU tables there are several AMATEUR-SATELLITE  
>>> bands allocated above 2 GHz, to very very high frequencies.
>>>
>>> What is the status of those frequencies in terms of past, present or 
>>> planned utilization on AMSAT / other satellites ?
>>>
>>> If those bands haven't been used, should they be not used or plans to 
>>> use them to protect them from being de-assigned to other services? Is 
>>> there room for experimental RF super high frequency and extremely 
>>> high frequency payloads on any mission to make some use of these 
>>> great resource?
>>>
>>> 73 de Samudra N3RDX
-- 

73,
Mike, N1JEZ
"A closed mouth gathers no feet"