"Television Sound" on vintage radios
 

I rescued my old Defiant MSH 938 from its resting place under the stairs yesterday and once a fault on its motor tuning selection switch had been rectified, found a space for it for regular use again. Quite a big space - it's a gigantic set!

This is one of the various sets, made just before and (I think) just after the war that offered "Television Sound" in addition to the standard wavebands. This was of course the 41.5 MHz AM transmission from Alexandra Palace. I get the impression this was normally more of a 'sales point' rather than a regular high performing feature. Having said that, the Defiant's manual promised it should be possible to receive the Alexandra Palace signal up to 40 miles away 'without much difficulty'. The aerial required was not stated.

In 1938 (and 1939?), the BBC used the television sound transmitter alone at times to broadcast high fidelity radio programmes. I believe 'Toscanini concerts' were included.

These days, those of us with Auroras or equivalent can use this feature again.

How many have tried doing this with their own sets? How well does your Television Sound section work? Is it stable and sensitive, or is does it suffer from instability or drift?

Lastly, which sets provided this feature and over what date range?

This was from when the '7-metre television band' was exotic stuff!

Steve

Re: "Television Sound" on vintage radios
 

Television sound has been mentioned in a few threads. One which I cannot now find concerned a massive late 1940's Bakelite radio (I don't remember which model) in which television sound was received on the short wave band, and it turned out that this was effected via a tuned circuit that allowed the 41.5 MHz TV sound carrier signal from the London transmitter to be received on the ~ 13.8 MHz short wave frequency position. I had such a radio myself, and it certainly worked effectively in the London area in the 1960's, and I had wondered why I could not get TV sound on that short wave frequency on my other radios. The thread also mentioned that TVs were available with no sound tuner for use with such radios.

Re: "Television Sound" on vintage radios
 

It must have been designed to receive 41.5MHz using the third harmonic of the local oscillator I suppose. Neat solution.

Re: "Television Sound" on vintage radios
 

I had a Murphy A50 wireless in for repair, that had a TV sound option on the wavechange switch. The owner said he remembered using that function in the past.
In the manual it is called "7m sound television sound"

John

Re: "Television Sound" on vintage radios
 

What was the Bandwidth of these broadcasts - up to 9,000 cps? Edward

Re: "Television Sound" on vintage radios
 

There was a handful of large, posh and expensive range-topping pre-war HMV and Marconi radio sets that boasted extensive coverage including an "ultra short" 5-12m band, or up to 60MHz. ISTR the RF amp was KTW61 with X64 mixer, externally driven by Z66 LO and with 2 IF stages. I imagine that they would have not been made in huge numbers, it would be interesting to know how many survive and how well they perform. Presumably image rejection was poor on this band- but as there wouldn't have been a huge amount going on above 30MHz, it wouldn't have been an overwhelming problem. Drift might have been troublesome with a relatively narrow (even "fidelity" position) AM bandwidth though. Perhaps coverage to 60MHz represented optimistic future-proofing as to additional Band I channels.

Re: "Television Sound" on vintage radios
 

There was a pre war Cossor TV that had a radio built in the top of the cabinet and that was the sound receiver! I don't know if that chassis was used in any other radio but it was a multiband radio with a 7m band.

Peter

Re: "Television Sound" on vintage radios
 

Apparently the 1940's radio that I mentioned in #2 would only work in the London area. A poster recalled how, when his family moved to the Midlands (within range of the Birmingham transmitter), he could no longer receive TV sound. The circuitry incorporated a filter that was very sharply tuned to the London sound frequency.

Re: "Television Sound" on vintage radios
 

Ekco A23.

Re: "Television Sound" on vintage radios
 

At the start of the television service I don't think any domestic sets offered this feature. It was something that cropped up in about 1938. Then after the war it faded away again... probably before 1949 when the service from the Midlands was added.

Steve

Re: "Television Sound" on vintage radios
 

I think that 10 kHz was the target for UK TV sound in those days, but right now I can't find a reference, although I think that I have seen it written somewhere. It was also 10 kHz post-WWII, the same as for MF broadcasting, but often limited by GPO landlines to something less than that. (Although the lines to Brookmans Park and Wrotham were 15 kHz.)

Cheers,

Re: "Television Sound" on vintage radios
 

There were one or two post-WWII receivers that covered channel B1 sound or even higher. A couple mentioned in this thread: https://www.vintage-radio.net/forum/...111407&page=5; were the Peerless 1546 and Mullard GFR520.

Cheers,

Re: "Television Sound" on vintage radios
 

I recall some excellent experimental stereo transmissions which used the FM station as one channel and the TV sound as the other. Ted Heath & his band.

Re: "Television Sound" on vintage radios
 

Just spotted this... in the Radio Times of January 6th 1939, (attached).

So it seems the television sound transmitter carried radio programmes in the early evening before the television service opened.

After this date, the practice seemed to end though.

Steve

Re: "Television Sound" on vintage radios
 

Yes, it was an EKCO A23, thanks. The thread I had in mind has probably been deleted as it was for a set for disposal, but in the photo in #1 of the thread https://www.vintage-radio.net/forum/...d.php?p=851644 the legend "Televison Sound" can be made out at the bottom of the Short Wave band.

Re: "Television Sound" on vintage radios
 

I wonder- was there any significant production, either by hobbyists or commercially, of 41.5MHz sound converters to MW/SW IF into existing radios pre-war? Such a thing would have been far more within many folk's reach than a TV set, even if it didn't have pictures! The valves would have been pricey then and existing techniques stretched but both "high-quality sound" and the tech appeal of "VHF" might have caught the interest. Post-war, such a thing would have been almost unexceptional with the quantity of surplus on the market looking for a use, indeed something like the appropriate Gee front end was almost there anyway.

Re: "Television Sound" on vintage radios
 

I'm not sure what sort of view The Authorities would have taken with respect to licensing TV sound-only receivers, apart from being fairly sure they would have expected listeners without pictures to pay something. Perhaps nobody was especially keen to test those particular waters?

EDIT: I remember, in the late '70s / early '80s, a radio with airband and something called "PB" which could pick up the 405-line sound from ITV .....

Re: "Television Sound" on vintage radios
 

In those days a radio was supposed to be licenced, so I expect that covered it.

Incidentally reading a BBC annual from the 30's, I was amused to see that the lowest percentage of licenced listeners were on Anglesey where I live, yet Caernarfon just over the water had the best licence figure for all Britain! We know where the goody-goodies lived then!

Re: "Television Sound" on vintage radios
 

In the early 1970's I had a cheap Hong Kong AM/FM pocket portable radio that I found would to pick up sound from the three UHF TV broadcasts on the FM band. This was in the days before the FM band filled up with local radio and commercial stations. I got one for my late uncle, who was hard of hearing. He used to use his with headphones when watching TV before he got a TV with a headphone socket.

I guess a TV sound-only receiver would have required a normal radio licence. From memory, the Wireless Telegraphy Act 1949 defined a television as an apparatus capable of receiving and displaying television broadcasts, so apparatus not capable of displaying anything would not have been a television for the purposes of the act. The present act uses a different definition.

Re: "Television Sound" on vintage radios
 

Ah, but as far as the BBC were concerned, you would be receiving something extra, something special that a normal radio would not pick up. If you're benefitting from the service, then you should be paying for it. If everybody had just listened to the sound without paying anything extra for it, and this did not convince enough people to get an actual TV receiver and so pay for an upgraded licence, the BBC would not have been able to continue running the TV service.

You can't expect a train guard to accept The train was still going there anyway, whether I bought a ticket or not as an excuse for non-payment .....