Radios Able To Receive Television Sound

[Paul_RK]

Originally Posted by Dave Moll

Even people who are registered blind need a television licence (albeit at half-price) to listen to television programmes...

A menu option on the same page confirms that they don't: "Provided that your digital box is only used to produce sounds and can’t display TV programmes you don’t need a TV Licence."

[greenstar]

The Ekco AW98, 1937 had a TV sound band. Just a 5v plus magic eye set, but a nice one.

[Restoration73]

Hallicrafters S20R (ca 1945) could tune up to 44MHz and receive the 41.5 B1 sound, but
it would be hard to describe this as a sensitive receiver.

Devices such as Celestion Tele-Fi were not really independant receivers, they just
picked up the 6MHz intercarrier FM sound leaking from the TV's video detector. Even
mono TV sound sounded good in the absence of line and field frequency noises.

[Dave Moll]

Thank you, Paul, for confirming that (as I surmised earlier) a licence is only needed to operate a device that is capable of producing an image, so that the radios under discussion are exempt.

[Brigham]

I think they are mostly exempt on the grounds of 'no service'!

[emeritus]

No doubt due to being dosed up with medicine and the late hour, perhaps I didn't adequately think though my previous posting. Of course, since the closure of the analogue service, an ordinary radio cannot receive present-day digital TV services, you need something with a digital tuner such as a TV, video recorder, or set top box.

Having made a further investigation, it transpires that it is in fact perfectly legal to use a STB (but only an STB) to reproduce the sound content of a TV programme, as long as this is all the installation is capable of doing.

The relevant legislation is "The Communications (Television Licensing) (Amendment) Regulations 2007" [SI 2007 No.718], [which amends the 2004 regulations mentioned in my previous post] and the relevant provision is found in its paragraph 6.

++++++++++++++++++++++++++++++++

Amendment of regulation 9

6. In regulation 9 ...

(a) ...

(b) after paragraph (1), insert -

"(2) But a digital set top box is not a television receiver for the purposes of that Part if it is installed in such a way that it can only be used to cause the production of sound through a device whose functions are limited to the production, or the production and recording, of sound."

++++++++++++++++++++++++++++++++++++

There is also the following explanatory note.

iii) Definition of "television receiver"

Regulation 7 modifies the definition of "television receiver" for the purposes of Part 4 of the Communications Act 2003 (c.21). The purpose of the change is to ensure that a digital set top box does not constitute a "television receiver" for the purposes of that Part, provided it is installed in such a way that it can only be used to cause the production of sound through a device whose functions are limited to the production of sound. This is to ensure that digital set top box used solely as a means of generating sound without pictures does not fall within the television licensing regime.

++++++++++++++++++++++++++++++++++++

The fact that this amendment to the definition of "television receiver" was necessary, suggests that my original conclusion that a TV licence used to be required to listen to (analogue) TV sound , was correct. The implication is that, while it is OK to use a STB, it would not be OK to use a digital VCR in the same way, as it has functions other than the production of sound.

So a blind person does not need a TV licence to listen to the sound content of a TV programme via a STB, although he would need to get a sighted person to use that person's TV to display the menus for things like retuning.

[turretslug]

I suppose tuning to 45 rather than 41.5MHz would have resulted in a field sync rasp through the speaker but that's hardly displaying a picture!

Presumably most of these "SW radios with extended coverage" would have used a typical 455/470kHz IF with a relatively narrow bandwidth, even in a "fidelity" setting, so tuning at 41.5MHz would be somewhat critical and prone to drift. I think most TV receivers of this era would either have been TRFs, or superhets with a high and relatively broadband SIF?

[Synchrodyne]

I think that the TV receivers would typically have had broadband sound IF channels. If non-intrusive rate-of-change noise limiters were used – which I think was or became the norm – then a wide IF bandwidth (maybe 200 kHz or more) was necessary.

The Mullard GFR520 radio receiver of the late 1940s (I’d imagine a very rare model) tuned over the range 540 kHz to 110 MHz, with a 10.7 MHz IF For the 27 to 110 MHz range, a 10.7 MHz IF was used, with choice of AM or FM. So this receiver would have covered the Band I TV sound channels.

The GE model 7-2945A transistor portable covered the old American VHF TV sound channels and NOAA weather radio as well as FM and AM (MW). I have one that I bought new in 1988.

NOAA weather radio, NBFM around 162 MHz, was covered by a downward extension of the TV high band range. As I recall NOAA broadcasts sounded quiet as compared with TV sound, not surprising because they were low deviation (I think something like ±5 kHz peak as compared for ±25 kHz for system M TV sound.)

Maybe the ICOM R7000 also qualifies? It covered all of the old all of the analogue TV sound channels, VHF and UHF, FM and AM, albeit in narrowband mode only for AM, as well as all FM broadcasting bands. But not AM broadcasting except for the 11 metre HF band. I also have one of these, dating from 1989 I think.

I suppose one could also include in this catgeory receivers such as the Eddystone 770R and 990R. I guess the minimum requirement here is a radio receiver that has coverage of at least one from the FM, AM and HF broadcast bands and some of the TV channels.

Originally Posted by raditechman

Some of the Jason tuners could receive TV sound as well as FM radio They were around during the 1960's.

Those Jason models were:

Jason JTV 1958-59
Jasonkit JTV 1958-59
Jason JTV2 1959 – c.1966
Jasonkit JTV2 c.1960 – c.1966
Jason Monitor 1960 – c.1966
Jasonkit Mercury 2 1960 – c.1966

All provided coverage of Bands I, II and III, with choice of AM (wideband) or FM. Thus they received VHF TV sound broadcasts, whether AM or FM, and FM broadcasts. The UHF TV sound tuner and o the extent that tuners rather than complete receivers qualify for inclusion here, then they fit.

TV sound tuners were offered by Motion Electronics (AM/FM, VHF and/or UHF) and Lowther (FM only, UHF only) from 1971. These do not fit here because they were TV sound only. However, from c.1974 Motion also offered a variant that also covered Band II FM stereo. I think that both Motion tuner varieties then survived until the mid-1980s, when they were replaced by a full TV tuner (video and audio) without FM. Chave Innovations, the apparent heir to Lowther for this branch of the previous Lowther product line offered from c.1977 the previous Lowther TV sound tuner (as the US-1) and a derivative (the VUS-1) that added FM stereo. How long these remained available I do not know.

In the US, FM-AM radio tuners that (typically optionally) covered the VHF TV sound channels (system M FM) were available from the mid-1950s. TV sound tuners (TV-only) were available from some of the Japanese makers from the 1970s or perhaps the late 1960s, but whether there were any that combined radio and TV sound I don’t know. (The full TV tuner plus radio tuner combination was also made, but given that it had a video output that was intended to feed a display device, it is I think excluded from this list.)


Cheers,

[peter_scott]

Originally Posted by turretslug

Presumably most of these "SW radios with extended coverage" would have used a typical 455/470kHz IF with a relatively narrow bandwidth, even in a "fidelity" setting, so tuning at 41.5MHz would be somewhat critical and prone to drift. I think most TV receivers of this era would either have been TRFs, or superhets with a high and relatively broadband SIF?

The first generation EMI TV/radios did use the 460kHz radio IF for television sound and the instruction says:

"A fair amount of frequency drift is inevitable on this model but it should not drift off the Television Calibration mark. If the drift is excessive an extra negative co-efficient capacitor may be fitted in parallel with the existing one and TC37 readjusted."

Curiously the television only EMI sets had a sound IF of 1.5MHz but had the negative co-efficient capacitor fitted as standard.

Peter

[Hybrid tellies]

Originally Posted by emeritus

In the early 1970''s I had a very cheap AM/FM transistor pocket radio that would pick up all three channels' television sound at several places in the 88 - 108 MHZ FM band. I bought one for my uncle, who was hard of hearing, so he could use headphones when watching TV. His TV didn't have a headphone socket.
When I was a schoolboy we were given one of those massive Ekco radios that I now know used a trap circuit for reception on the short wave and always wondered why I got no reception on the same SW frequency on our other radios.

Back in the early 1970's my first portable radio with VHF/FM was a cheapy Hong Kong special. We lived in west Cornwall and despite being 40 miles away from the Caradon Hill transmitter it could clearly pick up ITV sound which was the 405 line band 3 ch12 transmission. I don't know to this day how it was breaking through, two high for 2nd image IF, and it just happened on this one radio. Reception was very clear and the signal appeared on a quiet part of the FM band between 97 and 100MHz. So where as most people, using more expensive radios, just had the normal three FM stations to listen to, Radios 2,3 and 4, I had an extra station ITV Sound which was rather useful at times.

[dave walsh]

This interesting thread has developed two aspects, as already mentioned!

In the post-war VHF Band 1/3 section, through to UHF Broadcasting, there were various commercial or home built units designed to overcome a perceived inadequacy in reproducing what was actually a very good audio signal [at VHF initially] from the set itself! That was often a talking point within Radio and TV technical mags at the time.The modern version of this is paying out for a "Sound Bar" or a multi channel "Cinema" system. I experimented with feeding TV sound through the "Hi-Fi" system at various points but I didn't feel this to be a crucial matter. I do recall one 1980's UHF audio tuner design in Practical Television being featured on the cover. Ironically perhaps, add on units were never that popular until modern FS sets exposed some deficiencies in sound reproduction, due to a lack of overall mass/weight in the cabinets [which aren't cabinets anymore].

My attention is more focused on the pre-war Radios with provision for TV sound at 7-9 metre wavelengths or thereabouts-as referenced in posts 8* 11* 19* 20* 23* and 42* here. We had such a set on a shelf in my school Physics Lab and not having any info on that period I was quite fascinated [in the same way that the relatively few Medium Wave sets covering the Trawler/Amateur Radio Top Band also caught my attention]. I know that there have been at least two other whole or part threads relating to radios with an early SW TV sound ident, as I was trying to list them at one point and printed some info off. I've been trying to locate this without success so far, re my hard copy or the website. I think it's a significant but short lived aspect of television history in the UK.

Dave W

Although I was gifted some School Lab equipment at one point, including a Brass and Oak Wheatstone Bridge considered to be of no value, the "Wireless" had gone!

[emeritus]

One of the theads relating to the post-war Ekco with the trap circuit was in the "For sale" section and has been deleted.