Nice one dave my Sony 520 has 110khz filters and RDS comes with no problems.
My Denon 215 is playing up again as it did earlier this year no RDS on the display but there is on RDSspy when cold so it looks like a resistor or capacitor in the FM double tuning detection coil is drifting in value most likely a capacitor at fault.

I am going to look out for another Sony as a replacement for the Denon but I will have a go at repairing it.
I will be interested to see how you go on with the 311.

Andy

Hi Nick,

I've only had it for a couple of hours - and I'm in the last stages of wallpapering so I've only had time to test it and do a quick comparison.

I need to set the S311 up with the same filter set up as one of the other Sony's - which will be initially 3 x 150 and 1 x 110. Then I'll need to twiddle with the narrow gain settings.

As it came - it seems slightly less sensitive than the SB-920 - so the narrower filters should make the difference.

Rgds

David

Thanks for the link Chris Following on from what you lot all seem to be saying I'll get myself some 150s and 110s. It'd be good if I could get the narrow mode to stay narrow without distorting and losing RDS.

I really love the 920 though, it's such a good tuner. We've got a good community on here for advice on such things

Unfortunately you can't have really narrow selectivity and RDS. Considering that the filters themselves are relatively cheap from digikey I'd suggest getting some 180 kHz filters as well. Then you can try 3x180 and 1x80 and see how that goes. Then in wide mode you'll get better RDS sensitivity and in narrow mode when you need more selectivity you can have it - as you are unlikely to get an RDS signal anyway and any distortion is unlikely to matter too much as with a wider bandwidth you probably won't get the station.

When I was monitoring the Geminids meteor shower I had both SB920's in "wide" mode to give an edge for RDS detection.

Don't forget that RDS is not the only means of identifying a station. A combination of using FMList.org and streaming audio from the internet has helped me identify many a weak station. I recommend http://www.listenlive.eu as a web site that has nearly every radio station in Europe. Audio on the internet can be from 5 - 30 seconds (or more) behind broadcast - so you hear on the radio - open the webstream and often find you can confirm what station it was as you hear the same thing again.

David

[Wallpapering is done ]

Yesterday afternoon I decided to give my CCTV PC a cleanout and enable the onboard sound card while I was at it and installed RDSspy and set it up and it works perfectly so now as this PC can record RDSspy data 24/7.

As far as I am concerned modding receivers for RDSspy is a must because you can record PI codes and time the signal arrived the time it was there and the RDS data.

You can see RDSspy in action in the video below.

http://www.youtube.com/watch?v=8iWSVsIw07w

http://www.youtube.com/watch?v=32BS53qIboQ

In the last video you can see me pausing the playback so I can look at the info and you can speed it up or slow it down.
When no signal is there it does not record until a signal arrives so there are no big files to contend with as I recorded a whole day on the tropo opening 15/11/12 and it was recording signals all day and the file size was 13mb.

Andy

How many on here are using a Software Defined Radio setup for FM DX-ing?

I have recently acquired a Funcube Dongle Pro+ (a USB device costing around £150) which covers 100Khz up to over 1Ghz (with a gap 240-420Mhz) and when used with software such as SDR-Radio (a Technology Preview of Version 2 of this demonstrates FM Stereo and RDS very nicely) you can use the software to define the receive filter for you and recieve signals in any mode defined in the software of your choice, be it Wide FM, AM, SSB, whatever.

Tell us more! I'm considering purchasing one - but am holding back as I'm looking for a device which allows a 1-2 MHz wide segment to be captured (at an affordable cost)

The two key areas I'm keen to know about specifically realting to FM-DX are:

Is there any sign of overload under normal conditions? - which would show up as spurious signals

Is the sensitivity very good?

Rgds

David

Sittingbourne

This is a summary of my loggings on FM List for 2012 - mainly from the end of May when I started using the site extensively for logging.

Meteor Scatter

AUT 2
F 4
FIN 1
I 2
POL 25
ROU 1
S 5
SRB 1
SVK 14
CZE 3
D 2
Total 62

Tropo

AUT 3
BEL 126
D 462
F 109
G 23
HOL 57
LUX 30
NOR 3
SUI 1
Total 814

Sporadic E

ALG 5
BLR 12 (OIRT band)
BUL 4 (OIRT band)
CZE 1
D 2
E 29
F 8
FIN 7
GRC 1
HNG 2
I 62
MRC 1
POL 5
POR 3
ROU 7
RUS 12 (OIRT bsnd)
S 1
SVK 3
TUN 17
TUR 1
UKR 3 (OIRT band)
Total 186

A total of 29 ITU countries.

This excludes the regular Belgian, Dutch and French stations (unless the reception is unusual). A Tecsun PL390 was used for the OIRT band - fed by a halfwave horizontal dipole.

Rgds

David

Could be some good tropo on it's way for tomorrow, keep an eye out on the band

http://www.dxinfocentre.com/tropo_nwe.html

Conditions have been improving as the evening has gone on. Started off around 17:30 with weak MDR Figaro on 87.9 from Inselberg (679 km), hr1 from Sackpeife on 91.0 MHz annd RTL from Luxembourg on 88.9 alos weak an just about identifiable from the web stream. A few minutes ago RTL on 88.9 was strong enough to give a PI code and closer Belgian stations are giving full RDS on the peaks.

Forecast looks interesting but doesn't look quite as good as was showinf a few hours ago. Let's hope...

I had a few things earlier coming in but couldn't ID any of them, well I will be DXing tomorrow for sure. Should be good conditions tomorrow.

Starting to look up here now. 89.4 France Musique Boulogne was just in at virtually fully-quieting levels (barely audible 50 minutes ago) and 92.7 had France Inter audible as I tuned past it.

Monday & Tuesday are looking good for this part of the world so maybe I won't miss the peak after all (we are in Surrey this weekend).

You could, if you want to dip your SDR radio toe into the water, get hold of one of these cheap (approx 30 quid) RTL based USB dongles meant for receiving digital TV on a PC. They will cover up to around 2Mhz block of spectrum and the frequency range of these dongles is generally around 55Mhz up to around a Ghz, not exactly sure of the upper limit, so they are good for OIRT coverage as well.

Instead of loading the drivers supplied with the dongle, you download and install a different driver which then interfaces with SDR software.

Here are some links to give you more information:

http://rtlsdr.org/ (tells you about what dongles to look for)
http://groups.yahoo.com/group/rtlsdr/ Yahoo Group discussing dongles
http://sdrsharp.com/ Software including links to download the drivers you need
http://uk.groups.yahoo.com/group/SDRSharp/ Yahoo group discussing same.
http://www.sdr-radio.com/ Another SDR Radio software program. Version 2 under development supports the dongles, an ongoing project.

With regard to sensitivity, they seem to compare well to my Icom R8500 - I can see traces of the Sutton Coldfield TXs down here on the spectrum displays and the Wrotham TXs are borderline RDS strength, both on just a discone. You can adjust the RF gain of them in the software to get a good balance between sensitivity and overload.

All looks very complicated on first look but it's not that bad really! And the results are worth it.

Hope this helps.

Jim.

This is fascinating stuff! I'd never thought about it before. A quick search shows you can get a Terratec Cinergy T DVB-T stick (shown as supported) from Amazon for just over £21. I'm very tempted to get one and have a play!

The RTL chip in these USB sticks would also apparently be capable of decoding DAB with the appropriate software, I wonder if this exists too?

Can you record the stations you receive (e.g. to a PCM .WAV file)?

Hi,

I owned one of those USB sticks before they'd discovered how to use it for SDR - so I had a go as soon as the info became available and unfortunately found it was very deficient - spurious reception due to overload - and turning the gain down it went deaf. I live around 15km from Wrotham and also have Heart in Canterbury as a strong signal. I presume that Bournemouth is a quieter location. Mine only went down to 84MHz. WRPlus worked with it and included RDS decoding and I was excited by the possibilites.

Trouble is I'm now spoiled as knowing that a 2MHz or more spectrum chunk can be done - I can't settle for a single channel.!

BTW I bought it for £15 all told and got just to see what it was like - it came with software for DTV, FM and DAB - and is brilliant for what it is designed for. I got all the Freeview channels and the quality of picture was very good on the outdoor aerial. DAB channels received were as expected as was FM. It was no good for FM-DX as it has a very strong AFC and would pull the tuning across to a stong adjacent channel signal. I didn't notice this effect when it was set up as a front end to the SDR software though.

Rgds

David

Interesting David. Can you do DAB and Freeview DXing with it?

I picked one of these up today via eBay from a local seller so was nice & cheap. This model was introduced in 1988 IIRC. It has 3 IF bands, Wide, Narrow and Super Narrow. It uses 8 ceramic filters: two are in line for wide, another two for narrow, and a separate IF strip of 4 lots of 150kHz filters for Super Narrow. So you could install 110kHz and 80kHz filters in the Super Narrow IF path without affecting the sound quality in Wide and Narrow.

Condition is very good, just a few minor marks, and the display is bright and clear. I haven't had a thorough play with it yet but it seems very sensitive and the selectivity in Super Narrow is superb, probably on a similar level to my modded Kenwood KT-1100SD. I only have cheapo RCA leads connected to the amp but the sound quality seems very good, better than the Kenwood but not as good as the Yamaha T-2. I may have to get some proper interconnects for it like the Chord ones I am using for the T-2.

A couple of points: the signal strength meter is a bit odd: it jumps up to 2 bars on very weak signals and doesn't seem to go any higher than 4, even on locals, despite a scale going up to 7. Also it seems to go to stereo when there's barely any signal, so it adds extra noise. A gripe related to this is that if I change the mode to mono to cut out the hiss, and the signal level changes the tuner goes back to STEREO AUTO and will flick back and forth as the signal or interference varies. So there doesn't seem to be a way of keeping it in mono without constantly pressing the MODE button. The manual states that mono/stereo mode is set automatically so I presume it is working correctly. But this is going to be a pain when DXing.

Overall though, it seems to be a very nice tuner and has got to be one of the best DXers out there, gripes notwithstanding. If you see one cheap then I would recommend it.

Nice Enhancement to the south, getting Gem 106, Kiss 106.4, Smooth 106.6, BBC Leicester 104.9 and BBC Norfolk 104.4 all noise free RDS signals!

Yes the Denon tuner is getting low-powered London stations at present such as Rinse FM on 106.8. I also heard Scream London on 92.0 earlier on. The usual suspects from SE England are enhanced tonight.

Was getting the Sutton Coldfield TXes last night with full RDS at times, but couldnt find anything from further afield.

Nothing to get excited about here yet. It seemed better yesterday evening.

A few more notes after some more use.

It appears that the mode is triggered to stereo if a very weak signal is enough to light up one bar on the meter. So a signal fluctuating around that boundary level will cause the stereo to kick in & out. If the signal stays at one bar or above then it will stay in mono if you tell it to, but if the signal drops out and then comes back over that threshold the tuner decides to put it back in stereo again.

The TIC review states that the MPX filter (presumably the noise reduction button) does nothing. Well it works on my example. If you press it on a noisy stereo signal it seems to take a fraction of a second to decide but after that it does filter out the highest frequencies to reduce hiss. It appears to be dynamic and changes in response to signal strength.

This tuner comes with MW and LW as well as FM. I have the AM aerial attached on the back but all I get on 198 kHz is noise!

So in summary it appears to have a sound quality comparable to the Yamaha T-85 but with better selectivity. I'd guess it's on a par with the top Onkyos for DX capability!

This is also the cheapest tuner I've bought so far, at just £22. A great deal.

I've got a listenable signal right now from Heart Suffolk on 96.4, from Bury St. Edmunds.

I'm mainly getting UK stations such as BBC nationals, BBC Sheffield and Lincs FM. I was also getting Dutch and Belgians on some of the same frequencies in the car earlier, depending on which way I was facing!

96.4 - Heart Suffolk - Bury St. Edmunds/Great Barton (2 KW, 182 miles/292 KM) http://www.youtube.com/watch?v=sl5ohhPO0Ls
104.4 - BBC Norfolk - Great Massingham (3.67 KW, 150 miles/241 KM)
106.1 - Kiss FM - Stoke Holy Cross (4 KW, 177 miles/286 KM)
100.9 - Classic FM - Wrotham (250 KW, 237 miles/382 KM)
95.7 - VRT Radio 1 - Egem, Belgium (50 KW, 311 miles/502 KM)
102.7 - Radio 538 - Rotterdam, Netherlands (100 KW, 303 miles/488 KM)
104.9 - BBC Leicester - Copt Oak (8 KW, 132 miles/213 KM)
106.0 - Gem 106 - Copt Oak (8 KW, 132 miles/213 KM)
106.6 - Smooth Radio - Waltham (10.8 KW, 127 miles/205 KM)