Full duplex transceiver?
Back in the dim dawn of history, there used to be those who constructed transmitters that were separate from receivers. Although constructing such a thing is beyond me, I would like to see someone create a device that was intended to feed the input of an upconverter. I can already get general-coverage receivers at reasonable cost. If I'm computer controlling one or the other of them, or both, there is no real advantage to having the in the same physical box.
I can understand why such a thing might be less than perfectly useful for those who want a portable station, but it would seem to me to be just fine for someone who wants to operate a fixed station.
On 05/17/2010 05:38 PM, tosca005@umn.edu wrote:
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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