[amsat-bb] Re: Icom 9100

tosca005@umn.edu tosca005 at umn.edu
Mon May 17 15:38:31 PDT 2010


On May 16 2010, Sebastian wrote:

> Perhaps others such as DEMI, will see this as an opportunity and come up 
> with alternatives?

Well, keep in mind that DEMI's strength is in transverters, and what is 
hard to obtain for satellite operation from most common-place existing 
equipment is a full-duplex transceiver. I don't think that DEMI is likely 
to start building transceivers, but if you had a true full-duplex 
transceiver, they would have transverters available to upgrade the radio to 
the satellite bands needed.

Here's a thought: buy two SoftRocks for a lot less than the price of the 
Flex 5000 -- one would be the v6.3Rx/Tx and the other could be the V9 Rx 
only. This would net you two independent receivers and one transmitter, and 
with clever wiring, selection of VHF & up transverters, and maybe a little 
bit of software development, you could turn that into a software-defined 
radio that would be capable of full-duplex cross-band operation. (The V9 Rx 
would be the primary receiver, the receiver in the V6.3Rx/Tx would be 
"spare" or "extra" or even ignored.) You'd need to configure the 
transverters with "split IF", and use two coaxial relays to route the 28 
MHz SoftRock IF Rx and Tx separately to the correct receive and transmit 
transverters. A bit of innovation/homebrewing would be needed for 
convenient band-switching, since you would need to switch two different 
transverters into the correct "position" depending on the mode: V/U vs. U/V 
vs. V/S vs. U/S vs. L/S vs. L/U vs. whatever other modes you wanted to 
support. But 4 transverters (145, 435, 1269, and 2400 MHz) would give you 
lots of satellite modes. Oh, don't forget there are some birds with HF 
links and the SoftRock can do HF natively too...

If only I had the time to work on such a thing...

Ideally, the transverters would be dual frequency, so that you could tune 
to 432 terrestrial or 435 satellite; 1269 satellite or 1296 terrestrial; 
and 2304 terrestrial or 2400 satellite. Newer DEMI transverters with the 
synthesized LO board can be configured that way, at least on the higher 
bands. Then you'd have not only a kick-@$$ satellite system, but also an 
outstanding weak-signal terrestrial system.

Unfortunately, DEMI is once again revamping their lineup of products. Of 
course, this is good for us who want the latest and best, but bad for us 
who want something right NOW. Prices and specs are a little bit harder to 
obtain from DEMI right now, but I expect that the wait will be worth it.

73 de W0JT

>On May 15, 2010, at 9:43 PM, Michael Tondee wrote:
>
>> I guess once I put the upcoming V/U module in my Flex 5000 I'll have 
>> that amount of money in it but I won't have had to spend it all at once 
>> and IMHO I'll have a markedly better radio. Also one that isn't outdated 
>> a day after I walk out of the store with it.
>> 
>> On 5/15/2010 7:22 PM, Mik Forsythe wrote:
>>> Just left Dayton a few hours ago. Icom said that it is basically a 
>>> 7600 and a 910. It is bigger than the 910. It was in a display case so 
>>> I can't tell you what the feel was like of the weight. Price is in the 
>>> $4,000.00 range so that will kill a lot of the satellite market if you 
>>> ask me.



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