Elad FDM-S2 actual freq range

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Tim Bucknall
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Elad FDM-S2 actual freq range

Post by Tim Bucknall » 19 Apr 2019 19:43

I'm posting this as its the sort of thing i'd have liked to know

The VHF portion will work down to 71.67mhz with no loss of gain and up to at least 179.325 but with a drop off in sensitivity
lack of local signals in the 180-184 range means i can't be more precise but by 185mhz you're seeing spurious images

seems like the whole vhf airband is useable despite the "out of band" message no loss of gain noted
Rx: Burkhardt Reuter RDR54D1, Elad FDM-S2, Airspy HF+ w/ HS Publications 6 Element R3 -R5 Yagi on rooftop rotator V/H polarization options. Pira P275 RDS analyser

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John Faulkner, Skegness
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Re: Elad FDM-S2 actual freq range

Post by John Faulkner, Skegness » 19 Apr 2019 20:34

Interesting. I have never explored this on the FDM-S2. I guess most SDRs will tune outside their stated range to some degree.

satnipper
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Re: Elad FDM-S2 actual freq range

Post by satnipper » 19 Apr 2019 20:58

The S2 uses the undersampling technique for vhf bands but not the air band from 108-135. Though the performance is not too degraded apparently.

Tim Bucknall
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Re: Elad FDM-S2 actual freq range

Post by Tim Bucknall » 22 Apr 2019 11:28

should i start another thread for the airspy HF+ or use this one?

i haven't found the upper limit yet but its at least 270mhz (official upper limit is 260) i use it for the entire satcom band.
never had reason to tune above 270 so far

i'd love to know if it will go down to 55.25 but i don't have an rf source to test on and carriers on that freq are rare these days
Rx: Burkhardt Reuter RDR54D1, Elad FDM-S2, Airspy HF+ w/ HS Publications 6 Element R3 -R5 Yagi on rooftop rotator V/H polarization options. Pira P275 RDS analyser

Jim (Bournemouth)
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Re: Elad FDM-S2 actual freq range

Post by Jim (Bournemouth) » 22 Apr 2019 18:26

My antenna analyser will produce a signal.. I'll experiment with both SDRs when I get time
Jim, Bournemouth, Dorset. IO90BR.

Elad FDM-S2, Perseus/FM+, Airspy HF+, SDRPlay, Funcube Dongle SDR Rx; 8-ele OP-DES for Band 2, 8-ele LFA 2m, 3 ele LFA for 6m, 20/15/10m dipole, VHF vertical
.

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Tim Bucknall
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Re: Elad FDM-S2 actual freq range

Post by Tim Bucknall » 23 Apr 2019 09:48

thanks mate
Rx: Burkhardt Reuter RDR54D1, Elad FDM-S2, Airspy HF+ w/ HS Publications 6 Element R3 -R5 Yagi on rooftop rotator V/H polarization options. Pira P275 RDS analyser

Tim Bucknall
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Re: Elad FDM-S2 actual freq range

Post by Tim Bucknall » 25 Apr 2019 14:01

no idea what i was doing before when it only tuned down to 71.67
I'm now listening to the 70 mhz buxton beacon on the Elad
Rx: Burkhardt Reuter RDR54D1, Elad FDM-S2, Airspy HF+ w/ HS Publications 6 Element R3 -R5 Yagi on rooftop rotator V/H polarization options. Pira P275 RDS analyser

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