SDR# vs HDSDR & RDS Spy - Free FM

Here's a comparison between the capabilities of SDR# vs the HDSDR coupled with RDS Spy.

As you can see, SDR# is a little bit weaker than RDS Spy, and doesn't quite manage to decode the PS in the RDS. Other errors occur too.

This is using an IQ file recorded on my mobile SDR set-up. I was not in a good reception spot at the time, hence the lack of anything else surrounding Free FM.





CLICK HERE to download either the IQ file or a single frequency IF file to try yourself in whichever software you choose.

Software that will play the above linked file:-

SDR#
HDSDR

For RDS decoding in HDSDR...
RDS Spy

Use this to pipe the audio from HDSDR to RDS Spy...
http://vbaudio.jcedeveloppement.com/Download_CABLE/HiFiCableAsioBridgeSetup_v1007.zip
Link above taken from http://vb-audio.pagesperso-orange.fr/Cable/index.htm

Remember you need to set up the virtual audio cable to send out and 'record' 192000Hz (192KHz) sample rate. HDSDR needs to be set up to send out via the virtual cable, likewise RDS Spy needs to be set up to accept input from the virtual cable.

Portable SDR and Bandscan on Lansdown (remix)

I have recently started getting back into using my RTL SDR dongle and I discovered that it was possible to have Windows 8.1 on a tablet allowing me to use better software than just SDR Touch (an Android SDR app which is fine for listening but not so great if you want to make IQ / IF recordings) and also run the dongle from the USB socket alone although with reduced battery life. That means I don't have to take my laptop anywhere, which would be too cumbersome for me as I don't drive so all my outdoor radio adventures are done on foot, bus and train. Taking the tablet out with me is a lot easier. Although sitting in a field with the aerial in a tree and all the gear spread out on the ground is slightly embarrassing when dog walkers come by, I decided to have a go at my idea to do an SDR bandscan up on the hill at Lansdown. First time around, this wasn't so successful as I was in a hurry and getting cold (not great weather!), but it proved it was achievable. I did get some IQ recordings out of it, so not a total failure.

Tablet - Dell Venue 8 Pro running Win 8.1, Intel Atom processor
Software - SDR Sharp (SDR#) with RDS Data Logger plugin
SDR device - RTL-SDR Dongle, NooElec NESDR Mini 2 (R820T2 chip)

I'm very pleased with how this runs on the tablet with very few drop-outs. Pity I hadn't really set the gain up properly (I didn't notice any major problems at 87.5 so assumed it was fine all the way, but higher up the band it was overloading), plus trying to do a bandscan automatically with the RDS logger and recording to an IQ file doesn't really work very well as on playback you find the band is scrolled at irregular intervals.





Anyway, from the IQ files I managed to grab on this first trip, here are a few of the more interesting signals.


93.2 BCFM (can be stronger than this on Lansdown, but I'd have to move the aerial around a lot to improve it)
96.1 BBC Solent
97.2 Wessex FM
97.5 Somer Valley FM
96.6 Frome FM
98 Ujima (stange effect on some stations causes there to be a trough rather than a peak at the center frequency, not sure why this happens)
105.8 Wave 105
105.5 WCR (Warminster Community Radio)
106.3 Bridge FM



I went back for a second go last weekend. I think I was up there about 3 hours in total! I was freezing by the end :D I found that different spots on the playing fields gave slightly different results, so had to try and do my best moving around with my flimsy wire dipole stung up in different trees / bushes, or even just being held as I was walking around. I need to build a portable wire yagi I reckon, one I can fold up and stuff in my backpack. I won't bore you with more videos, here's the best I can do going by what's in the IQ files...

87.5
87.6
87.7
87.8
87.9
88.0
88.1	Radio 2
88.2	Radio 2
88.3	Radio 2
88.4
88.5	Radio 2
88.6	Radio 2
88.7
88.8	Radio 2
88.9
89.0	Radio 2
89.1	Radio 2 (possibly)
89.2
89.3	Radio 2
89.4
89.5	Radio 2
89.6
89.7
89.8
89.9	Radio 2
90.0
90.1	Radio 2
90.2
90.3	Radio 3
90.4	Radio 3
90.5	Radio 3
90.6
90.7	Radio 3
90.8	Radio 3
90.9
91.0	Radio 3
91.1
91.2	Radio 3
91.3	Radio 3
91.4
91.5	Radio 3
91.6
91.7	Radio 3
91.8
91.9
92.0
92.1	Radio 3
92.2
92.3	Radio 3
92.4
92.5	Radio 4
92.6	Radio 4
92.7	Radio 4
92.8
92.9	Radio 4
93.0	Radio 4
93.1
93.2	BCFM / Radio 4 (directional)
93.3
93.4	Radio 4
93.5	Radio 4
93.6
93.7	Radio 4
93.8
93.9	Radio 4
94.0
94.1
94.2
94.3	Radio 4
94.4
94.5	Radio 4
94.6
94.7	BBC Hereford and Worcester
94.8
94.9	BBC Bristol
95.0	BBC Gloucestershire
95.1
95.2	BBC Oxford
95.3
95.4
95.5	BBC Soms
95.6
95.7
95.8	BBC Gloucestershire (or Wales, dunno!)
95.9	BBC Wales
96.0	BBC Unid - Too far back in the mush
96.1	BBC Solent
96.2
96.3	Heart
96.4	Maybe something
96.5	Unid - Too far back in the mush, Could be Wave or Heart
96.6	Frome FM
96.7	Heart
96.8	BBC Cymru
96.9
97.0	Fantasy Radio (Proabably!)
97.1	Heart
97.2	Heart / Kiss 101 / Wessex FM (Directional)
97.3
97.4	Capital - Quite hidden by Somer FM
97.5	Somer Valley FM
97.6
97.7	Radio 1
97.8	Radio 1
97.9	Radio 1
98.0	Ujima
98.1
98.2	Radio 1
98.3
98.4	Radio 1
98.5
98.6	Radio 1
98.7	Radio 1
98.8
98.9	Radio 1
99.0
99.1	Radio 1
99.2
99.3
99.4
99.5	Radio 1
99.6
99.7	Radio 1
99.8
99.9
100.0	Classic
100.1	Classic
100.2	Classic
100.3	Classic
100.4	Classic
100.5
100.6	Classic (slight trace)
100.7	Heart (slight trace)
100.8	Classic
100.9
101.0	Kiss 101
101.1
101.2
101.3	Classic
101.4	Classic
101.5
101.6
101.7	Classic
101.8
101.9
102.0	Spire FM
102.1
102.2	Heart
102.3	Heart
102.4	Breeze
102.5
102.6	Heart
102.7
102.8	Breeze (slight trace)
102.9	Heart
103.0	Heart
103.1
103.2	Capital
103.3
103.4	BBC Devon
103.5	BBC Wiltshire
103.6	BBC Bristol
103.7
103.8	BBC Solent
103.9	BBC Wales
104.0
104.1	BBC Berkshire
104.2
104.3	BBC Wiltshire
104.4	Unid (slight trace)
104.5
104.6	BBC Bristol
104.7	Unid (slight trace)
104.8
104.9	BBC Wiltshire
105.0
105.1
105.2	Wave 105
105.3
105.4	Heart
105.5	Swindon 105.5 / WCR (directional)
105.6	Breeze
105.7	Heart
105.8	Wave 105
105.9	Heart
106.0	Sam FM
106.1	Badminton Radio (RSL)
106.2	Sunshine
106.3	Bridge FM
106.4
106.5	Sam FM
106.6	Breeze
106.7
106.8	Nation
106.9
107.0
107.1	Unid (slight trace)
107.2	Breeze
107.3
107.4	Breeze
107.5
107.6
107.7	Sam FM
107.8
107.9	Breeze
108.0

I have a better SDR device on the way - an SDRPlay - which doesn't suffer so much with overloading and images. If I can get that running from the tablet, it'll make things even easier for bandscanning, but it might be a bit too much try to power it from the USB socket alone.

Radio Badminton 106.1MHz - RX Bradley Stoke 2015 05 08

The RSL station for the Badminton Horse Trials, Radio Badminton, manages to make it 11 / 12 miles on 106.1MHz. In the past I've heard it in Alexandra Park (on a big hill in Bath). Of course, this is with finely tuned filters, loft aerial and .1 away from Sunshine so a regular radio may not be able to hear it. I have to have the Tecsun radios tuned to 106.07 to be able to hear it.

Faze FM Southampton

A new pirate popped up in Southampton recently, Faze FM on 87.5. It seems to be primarily a DnB station (yay!) and has a huge reach. The furthest North I've heard it at anorak listening levels is just south of Bath on the train going down to Warminster and Salisbury. I also may have heard it even further North on the massive hill at Birdlip near Gloucester, but that was on a car radio (boosted aerials and big groundplane from the car body helps a lot pulling in signals) and I couldn't confirm this as it was just a blank carrier and at the time no RDS to decode. That said, it's also been heard the same distance away on high ground in Watford, so it's certainly possible.

This was recorded up a hill in Warminster. I tried to get better reception but ended up wandering around a lot while recording this. The best place was on a golf course where I didn't feel like hanging around looking out of place for too long. Much better reception in Salisbury a week later but no live shows... Listen for my shoutouts ;)

Faze FM 87.5 Southampton RX Warminster 18042015 by Bristol Radio Recordings on Mixcloud

Free FM 10/4/2015

Here is a recording of Free FM from a few weeks back. It wasn't a long broadcast that evening as the stream it was relaying started to stutter after only 20 mins and eventually they gave up to try again another day. I managed to catch the RDS too...

Free FM 105.8 - Caroline 319 Relay - 10/4/2015 by Bristol Radio Recordings on Mixcloud