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Re: Features in FT-847 replacement, wish list

At 07:49 PM 12/22/2005 -0500, Andrew Glasbrenner wrote:
>>I agree that the linked TX/RX sat tuning is a cool feature, but I think it 
>>can be improved upon. The current linked tuning ratio on the 847 is 1 to 1 
>>when the ratio of Doppler shift on 70cm compared to 2m is approx 3 to 1. Of 
>>course, you can use the sub tune knob to fine-tune the uplink, but its use 
>>could almost be eliminated if the VFOs tuned in the proper ratio. It seems 
>>to me that enabling the feature would improve the clarity of FM voice 
>>transmissions at lower elevations where the TX side is slightly over/under 
>The purpose of the linked tuning isn't to correct doppler though. The 
>purpose is to be able to QSY across a transponder and still maintain the 
>proper uplink-downlink offset. What you suggest would work on the FM 
>repeater sats, but for the most part, so would unlocking the VFOs and tuning 
>the UHF only. SO-41 (RIP) and the ISS repeater are probably exceptions to 
>this, as their uplinks receivers are a little narrow.
>For FM reception of satellite signals, the AFC found in the 910 is the 
>absolute cats meow. On AO-51 mode S I don't have to touch the VFO the entire 
>I would LOVE to see a bandscope like the 756 has on a sat rig. Finally we 
>could all see where the activity is on FO-29 or VO-52, as well as have a 
>constant reference of how loud we are compared to the beacon.
>73, Drew KO4MA 


Since the begining of this topic, I have been reading parallel threads on
other lists that suggest to me that my next rig will be a SDR.  At this
point in time the SDR-1000 comes closest to hitting the mark with windows
based sw and closest to plug-n-play.  For satellite operation it will take
a two twin transceivers (currently a single SDR-1000+2m = $1100); hopefully
a second one can be added for less than $2200 total.  {see review in Oct.
2005 QST or go to FlexRadio website}

I think the days of the complete hardware box are nearly over, so a dual
TX/RX SDR is what I see as the target rig.  In time we may see a direct
conversion 144-MHz SDR!  At this point it looks like 50-MHz is the upper
limit...requiring xvtrs to get on higher freqs.

For those experts in sw development other SDR platforms are perhaps better
or cheaper?  For an old microwave hardware guy the SDR-1000 looks like the
easiest way to ease into the SDR world.  Once there, all the other
enhancements are done in sw: auto-track, auto-tune, Doppler correction,
DSP, digital filters, wideband spectrum monitoring, digital modes, etc...
i.e. C-C Rider!

my two cents from the bleachers! :-)
Ed - KL7UW  
http://www.qsl.net/al7eb - BP40iq 
144-EME: FT-847, mgf-1801/1402, 4xM2-xpol-20, 170w
432-EME: FT-847, mgf-1402, 1x21-ele (18.6 dBi), 60w
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