Hi Fi tuners

[KeithsTV]

Originally Posted by paulsherwin

Broadcasters haven't switched the transmitter chains to mono for mono material since the 1980s. I think they just decided it wasn't worth the hassle, especially as people would think their stereos were broken when the pilot light was off. There is actually almost no mono programme production today anyway.

I believe the RDS data transmitted requires the 19k pilot tone to be able to decode the data as the data rate and the 57kHz subcarrier are locked to the pilot tone.

Keith

[paulsherwin]

I don't find electrical hash is a significant problem with FM reception even with a bit of wire hanging out of the back. The biggest reception problem is multipath which causes obvious sibilance on female speech. This can be very difficult to eliminate even with a good external aerial.

[Nickthedentist]

Yes, a bit of wire gives top-notch reception at my place (other side of Oxford) too, with no sibilance, fortunately.

This is where newer (late 70s/80s/90s) FM tuners really are an improvement on most of the earlier ones.

[G6Tanuki]

Where I am (west Wiltshire) I can only get the BBC national/local stations, classic-FM and what-was-once-GWR with a bit of wire.

With the UKA8 pointing down the Kennet valley I get Capital FM on 95.8, LBC on 97.3 and XFM on 104.9 with a sensible level of quieting.

Just goes to show how far a Band-II FM signal will go ...

[paulsherwin]

Higher parts of Oxford used to get Capital and LBC quite well before the band filled up with Radio Borsetshire or whatever. I spent 1981 living in a shared house on the Botley estate and both stations were fine using an indoor aerial and a very nondescript tuner. If you wanted to listen to them now you'd need something highly directional pointing in the right direction.

Originally Posted by stevehertz

FM is by far the highest quality form of radio broadcasting

Indeed it is given a high signal strength and a good source of audio. I think the source for most FM transmitters is still the old 13bit digital link, you can get better from a 'Freeview' set top box.

[neutronic]

With a 70s Sony tuner I have a better AM reception than almost all of my valve radios.
Even better than a Realistic 302 DX receiver!
Proven by listening to English MW-stations in my shed.
Necessary because where I live ( West-coast) Dutch stations are very weak or religious.
Jard N.

[G8HQP Dave]

Originally Posted by G6Tanuki

A good, gainy, narrow-beamwidth horizontally-polarised antenna (and rotator) helps a lot - sometimes to peak up the weak signal, othertimes to shift a semi-local nasty-noise-source into one of the sidelobe nulls.

Unfortunately my neighbour's solar PV system is in roughly the same direction as the Peterborough FM transmitter.

Complain to Ofcom.

[mhennessy]

I use a Technics model in my main hi-fi. Elsewhere, we have a couple of Denon DRA-455 receivers, which combine a decent tuner with a good 40 (IIRC) watt amplifier - and the whole thing is remote controlled. One in the kitchen/diner and one in the lounge. I did buy one of these new (£200) about 13 years back, but the other was £20 second-hand. Highly recommended.

In the workshop, I have an old Sony ST-S311. This RDS unit from the early 1990s has a feature that is especially useful - and not seen very commonly in my experience of hi-fi tuners - the ability to type in the desired frequency with a keypad. Great for checking out distant stations - much quicker than manually tuning.

Over the years, I've chosen according to features and ergonomics and aesthetics; I learnt a long time ago that in the hi-fi tuner world, anything half decent and half modern, and in full working order, will sound exactly the same as anything else. Knowing what I now know about the broadcast chain, I feel fully justified in that position!

Before moving to Evesham, I too needed little more than a bit of wire hanging out of the aerial socket. Sadly, around here, FM is very poor indeed. I have a "temporary" dipole strung up inside the loft, just under the ridge, and that signal is fed to a distribution amplifier - decent CT100 cable is used everywhere. But it's a bit weak - I definitely need a multi-element unit mounted on the chimney. Analogue TV was also very poor back in the day (once upon a time, they used a dedicated microwave link to get a good analogue TV signal at Wood Norton).

[AlanC]

I think the issue is that a good FM tuner will always sound better than a mediocre DAB stream and that, to me, is why they are worth bothering with, and untimately why they will survive. I have here a Leak Troughline II which is an excellent tuner and is in daily use, it's a fickle thing requiring complex alignment (has to be swept) and there are probably many solid state tuners with better performance, but I love it's warm sound and very quiet background. I'm about 3 miles as the crow flies and line of sight to the Sheffield transmitter, and a simple wire dipole is plenty enough antenna.

[vinylspinner]

I still think that a good FM tuner is worthwhile, I listen to radio 3 most evenings, some excellent broadcasts, Late Junction is always a quality listening experience, the radio play on Sunday evening is also good.

Nigel

[Jonster]

The Denon TU260L mentioned earlier is indeed a very good tuner. I have found that the better Technics models (identifiable by a their switchable IF bandwidth) also have very good RF performance, the best I have come across however is the Sony ST-SB920 which combines great sensitivity and switchable selectivity with completely transparent audio performance and a very full set of RDS functions as well.

The limiting factor in most tuners are the 10.7 MHz ceramic filters. Changing these for better Murata ones can transform quite mediocre models into something that sounds pretty good.

I have also come across several older tuners where the tuning has been 'off' so that instead of Radio 2 coming in clearly on 89.1 the tuner locks to 89.15 instead. This is caused by the discriminator having drifted, a quick tweak of the core with an appropriate trimming tool soon brings everything back to where it should be. I have seen 3 Denons with this fault.

[Radio Wrangler]

Originally Posted by merlinmaxwell

Indeed it is given a high signal strength and a good source of audio. I think the source for most FM transmitters is still the old 13bit digital link, you can get better from a 'Freeview' set top box.

I used to read each BBC research department report as our library got it. I believe their first NICAM system was designed for distribution of programme material to their transmitters while still retaining the leased lines already in use. Only later was a version created for broadcast to TV viewers.

It's curious how people still treat stereo FM transmissions as the full analogue experience when they're now only the last link in a fairly long chain. The NICAM distribution format was designed to do the best job possible within fairly strict data rate limits, and the BBC researchers seem to have made a good job of it. On a good tuner, they still sound good.

David

[G6Tanuki]

Originally Posted by merlinmaxwell

I think the source for most FM transmitters is still the old 13bit digital link, you can get better from a 'Freeview' set top box.

That may be true for 'national' big-players but I'm not sure if the likes of LBC would have such heavy distribution-architecture to go from their studios to their transmitter. And the local Freeview muxes (when they're actually receivable here) only carry a regionally restricted range of content anyway.

The nice thing - apart from the excellent audio-quality - about Sky is that you can do "postcode-DXing" - put in an out-of-area postcode and see what the 'locals' in Norwich or Northumberland are watching/listening-to. Though I'm officially in a "SN" [Swindon & Wiltshire] postcode most Sky-boxes I come across are configured with London postcodes.

[Restoration73]

Interference pulses on Freeview cause sound muting, but on FM you might hear a click.
I prefer the latter. For those not working in broadcast, FM delivered quality only exceeded
by a good LP pressing or a 7.5 ips tape. Recently I have acquired some FM off-air tapes
recorded on open reel in 1969, these now sounding as good as broadcast.
Early tuners may have used the Foster Seeley detector which was totally displaced by
the ratio detector prior to the advent of the IC quad detector.
Early tuners may have used a discrete switching stereo decoder, again the performance
was greatly bettered by the advent of the IC PLL stereo decoder.

[Jonster]

Originally Posted by KeithsTV

I believe the RDS data transmitted requires the 19k stereo pilot tone to be able to decode the data as the data rate and the 57kHz subcarrier are locked to the pilot tone.

If the 19kHz pilot is present then the 57kHz is indeed locked to it and should be set 90deg out of phase (in quadrature) in relation to it. It is perfectly feasible to run RDS without the 19kHz pilot tone though, in fact some RSL broadcasts (for things like sports events where stereo is not needed) do this.

[turretslug]

Originally Posted by mhennessy

In the workshop, I have an old Sony ST-S311. This RDS unit from the early 1990s has a feature that is especially useful - and not seen very commonly in my experience of hi-fi tuners - the ability to type in the desired frequency with a keypad. Great for checking out distant stations - much quicker than manually tuning.

Also the ST-S370 (which I suspect is little more than a cosmetic face-lift of the '311). These can be had for a song in the usual places and have plenty of user appeal- as well as the direct frequency entry, they have rotary encoder tuning, rather nicer than the than cheaper but less ergonomic up/down buttons. Also a narrow bandwidth FM option. There's a signal strength display option in dB- whether these Sony db have anything to do with the measurement world I'm not sure but they do give a good resolution relative indication for playing with aerials/feeders/pre-amps/distribution etc. In AM mode, adding a single 1N4148 etc. in the appropriate place in the synthesiser gives full 144-288kHz and 522-1620kHz coverage in 1kHz steps (if that floats your boat). Excellent devices.

[Jonster]

The Sony (and Technics) signal meters are fairly accurate and 0dB is referenced to 1uV, so 40dB shown on the meter is 100uV, 60dB is 1mV etc.

[music-centre]

I certainly still like to keep a Tuner in the couple of Stereo systems I have,I use a Leak Stereofetic and a later Leak Tuner-amp which both work well and a fairly recent Technics one which is convienient with its pre-sets.I still seem to like the sound better from the older ones for some reason though,I can remember saving up for a Sony one with digital tuning in the 70s when they became affordable but never thought it sounded as good as a Cheap Teleton one that it replaced.
Recently got an A&R T21 that I remember was far too expensive for me at the time but it doesnt seem to be anything special on a quick test - Glad I didnt lay out all that
money when they were new!
Steve.