Hi Fi tuners

Originally Posted by G6Tanuki

about Sky is that you can do "postcode-DXing"

Sounds like fun, anything worth listening to though?

[G6Tanuki]

It's intriguing to occasionally listen to out-of-area "local radio" from where you grew up/lived previously.

And not all the commercial-radio stations have yet been combined into playing out the same content on all their regional tentacle-ends.

(I rather like Kiss 100: they do some good coverage of music festivals).

[WaveyDipole]

I take the point about the amount of choice and not needing to put up with cosmetic damage. I had another look at it today - this time with glasses on! The marks are actually flaking off paint rather than scratches. It has probably been knocked a couple of times or dropped and the paint is flaking off at the 3 points where it was bumped. Its not as bad as I first thought, but it could be described as having wear and tear consistent with its age.

Incidentally, does anyone know anything about a Wharfedale Sys 5000 Tuner? This one was immaculate but PLL rather than analog tuner. Unfortunately I can't find hardly any information on it, not even what bands it has, but suspect it is a rather modern budget item.

[Nickthedentist]

Yes, suspect the Wharfedale is an Argos (or similar) offering.

[paulsherwin]

Some of these late 90s and after Wharfedale / Goodmans / whatever tuners aren't that bad. I have one (99p purchase) and the only reason I don't use it is that all the station memories disappear whenever the mains is disconnected. It has a nice rotary control for up/down tuning as well as the usual presets, and the sound quality is pretty good. These tuners can be a sensible listening choice if you can stand the howls of derision from your 'audiophile' mates, a bit like buying a Skoda in the old days.

[stevehertz]

Paul, standardised chipsets have played a big part in sets having similar (and decent) performances in modern tuners. And I agree re the snobbery. I'd like to see the results of true blind listening tests in this and many other aspects of hi-fi.

[Synchrodyne]

I’d say that the era of “standard” ICs for FM tuners goes back to the introduction of the RCA CA3089 (1971) and Motorola MC1310 (1972). Much of what followed was development of these types.

The CA3089 was a multifunctional, high gain FM IF/demodulator IC, and could be described as a fourth generation RCA product in the consumer FM IF field. (The preceding generations were the CA3012,4; the CA3041,2,3, and the CA3065, CA3075,6.) It was RCA’s first to include a quadrature demodulator based upon a transistor-tree mixer, although that feature was by then quite common in TV intercarrier FM ICs. Apparently Sprague was the first with that kind of demodulator with its ULN2111A in 1967. I don’t think that the CA3089 had any real competitors at the time, although it was much-cloned.

The MC1310 was a PLL-type multiplex stereo decoder. It was not the first of its kind, having been preceded slightly by RCA’s contender, the CA3090, which it rather overshadowed. It might have also followed the Fairchild µA758, to which was very similar. Possibly the MC1310 dominated because Motorola had been first with a (non-PLL) stereo decoder IC, the MC1304,5, in 1968 (or 1969), and so was an established supplier to many equipment makers, who then found it quite easy to upgrade to PLL decoders using the MC1310. The MC1304,5 was one of several ICs that suggest that once having embraced the integrated transistor-tree mixer, Motorola was determined to use it in every conceivable application, thus quickly overtaking Sprague. (Even the ULN2111A seems to have been better known as its Motorola clone, the MC1357.)

During the 1970s, Hitachi and Toko made much of the running with improved versions of the CA3089 and MC1310, and their successive efforts - including pilot-tone cancelling decoder ICs - were well-documented in the Ambit catalogues of the period. Performance in respect of noise, distortion, muting, etc., was ratcheted up in stages. The American IC makers were not entirely absent, though, and for example RCA released the CA3189 in this period.

In the 1980s, Sanyo came to the fore with its FM (and AM) ICs. Possibly that was because it had anticipated the widespread use of electronic tuning, and had developed FM IF ICs that whilst essentially of the CA3089 type, also interfaced easily with those tuning systems, for example by providing pinouts for “stop” commands. Another development of that period was the National LM1865. This added an IF pre-stage to what was a CA3089 type “back end” with an electronic tuning interface, and introduced a dual wideband/narrowband front end agc system. Hitherto IF pre-stages were usually outside of the main IF IC, and were variously discrete bipolar, discrete fet or IC at individual maker choice.

As well as the ICs, some passive components were also standardized in the same period, notably ceramic IF filters. Also, lumped L-C IF filters and L-C pilot tone/multiplex filters (maybe even “birdy” filters) became available as standard components from the usual suppliers. And front end designs seemed to coalesce around dual-gate mosfets in the RF (one or two stages) and mixer positions.

All of that said, though, I recall at one of the late 1970s London hi-fi shows asking one equipment maker whether the standardization of FM tuner ICs constrained design possibilities and enforced a “sameiness” to this product class. The answer was no, that the situation was essentially no different to that which had obtained during the valve era. I suppose when one looks back, the valve set used across FM tuners generally was not all that diverse.

Originally Posted by Restoration73

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.

The transition to the IC-based quadrature demodulator, once it became available, as the norm for FM tuners was understandable, although there were some departures here and there, sometimes into more exotic forms. However the migration from Foster-Seeley discriminator to the (Seeley-Avins) ratio detector was counterintuitive, at least by the conventional wisdom of the valve era. That had the Foster-Seeley type as being preferred for high quality applications because of its lower distortion as compared with the ratio detector. However, the Foster-Seeley required a limiter stage ahead of it whereas the ratio detector, with its self-limiting properties (although these have been disputed) would work without a preceding limiter stage. Thus the resultant saving of one valve in the IF strip made it attractive for lower cost applications. But to be reasonably self-limiting, the ratio detector had a relatively narrow bandwidth, and the Foster-Seeley distortion advantage accrued when it had a comparable bandwidth. A wideband ratio detector had adequately low distortion, but lost its self-limiting properties, and so required really good limiting ahead of it. It also had a lower audio output. Apparently the wideband Foster-Seeley type ran into other difficulties that made the ratio detector a better choice if one opted for wide bandwidth, which typically brought the benefit of a better capture ratio. Wideband ratio detectors were in the minority in the valve era, but not unknown. For example, American maker H.H. Scott favoured them from the start, and Radford used one in its FMT1. The latter had a four-stage IF strip (with 3 limiting stages), which was probably quite unusual in British practice.

In the solid state era, once consumer equipment-oriented ICs arrived (in 1966), the situation changed in that obtaining more-than-adequate limiting became quite easy, thus facilitating the use of wideband ratio detectors, which then became the norm until the quadrature type established itself. As RCA stated and restated, the integrated differential amplifier, with its closely matched transistors, made an ideal FM IF limiter, as it provided symmetrical limiting over a wide input voltage range.

Originally Posted by Restoration73

Tuners lacking LW were aimed initially at the American markets.

Although back in the later 1950s, some of the UK makers were a bit naughty in leaving out LW on some of their FM-AM models that were aimed the domestic market. Armstrong and Jason come to mind in this regard.

Cheers,

[Biggles]

I too have a collection of tuners. I just wish I had more houses to use them in! My present set up at work is a Trio KA-2200 tuner amp, coupled to a pair of second hand Panasonic speakers. Even with the poor signal level and local interference from a large equipment room situated next door to the workshop the sound is second to none, hiss free and has just the right tone about it. I have to clean the switches occasionally but apart from that it just soldiers on day after day. I quite like the wooden cased brushed aluminium look of the late seventies. It's a pity so much of it has been binned for the modern plastic rubbish.
Alan.

[TIMTAPE]

Here in Australia I regularly listen to our BBC equivalent, ABC FM and it's fine. But FM stereo could never match say a CD for dynamic range. FM radio, including BBC/ABC has always compressed/limited the signal for lower FM noise at the receiving end, making it appear to be quieter than it really is. For many of us oldies the compression is a boon as it somewhat compensates for our flagging hearing and intolerance to loud sounds.

Tim

[BGmidsUK]

My tuner is the Technics ST-GT630, bought from the shop in Loughborough we ran for a while (a Panasonic Technics Centre) when they were clearing the stock but still expensive at £150. It appears to be one of their better ones, with switchable IF bandwidth, signal strength meter, plenty of presets and lots of other nice features. I chose it on spec as well as appearance as it matches my other units well.

Sound quality is as good as you can expect from long and medium wave AM and VHF FM transmissions, it's sensitive too especially in narrow-band mode.


Brian

[John Caswell]

Hi all,
I run a Magnum Dynalab MD100 as my main house tuner, which I have modified to have switched antenna inputs. For aerials I have a "search" halo sitting about 30' up with a Fuba UKA8 below on a rotator.Once I have found something on the "search" I usually rotate the 8 el to suit which pretty well always drives the MD100 into full quieting, wonderful silent background.
I would like to get a "T" version of one of the top MD range but cannot really justify the cost.
I will not get a DAB unit until they switch off FM.

John

[MotorBikeLes]

I have a JVC HiFi in living room (acquired thro work, guy brought it in, asked for a repair quote, but decided to buy new and said we could keep it. I ordered a replacement remote, but then he brought in the one belonging. A similar unit from amenity site powers the motor 'bike shed, using the spare remote. In my electronic w/shop (spare bedroom), I use the NordMende Parsfal radio, but sitting next to it is the Korting 7402 tuner amp with siezed tuning gang. I am considering "releasing" the Parsifal to some willing customer and using the Korting again. Those FM push buttons are so attractive, but I really can't knock the Parsifal. I am on a bit of a (SWMBO inspired) space reclaim exercise. Les.