Television Phenomena 

21 October 2020 tbs.pm/71275

Interference by New York police radio

 

 

Sussex Express masthead

From the Sussex Express & County Herald for 28 November 1947

It will come as a shock to television enthusiasts to be told that their interference troubles may be caused by a New York police radio station and one of its mobile radio ears.

This phenomena is put forward in a letter to the Editor of the “Sussex Express and County Herald,” not as a theory but as a confirmed fact, by Belcher (Radio Services), Ltd., wholesale radio specialists, of London and Cippenham, Bucks, who have a regional service and research station at Morris-road, Lewes.

The letter is from Mr. F. H. Clitheroe, A.M.I.E., Assoc.Brit. I.R.E., the company’s regional technical manager.

Sir, – No doubt several of your readers have read conflicting reports in the national Press concerning the complete failure to receive television pictures from Alexandra Palace during some afternoons, due to severe interference in the form of vertical bands.

This technical department at Lewes has been monitoring the wave-band area covered by the television transmissions, and can now confirm one report that this interference is caused by American police radio.

 

Map showing New York and the UK

Underlying map by TentotwoCC-BY 3.0 licence

 

The station mainly causing this trouble is American Police Station W.V8Q and its associated stations, including police mobile van P.X. call its base.

To radio engineers, this seems almost unbelievable, for these stations are supposed to have a range of about 25 miles [40km] in or around New York City, and they are now jumping many thousands of miles, causing this havoc to B.B.C. television pictures. We have been in touch with the B.B.C. concerning same, and the report on our findings has been confirmed by them.

This most unusual phenomena is, we hope, only a temporary one. The B.B.C. and ourselves can only reassure owners of television sets that there is no fault in their apparatus causing this trouble.

 


 

❛❛Russ J Graham writes: If you’re old enough to remember analogue television (it hurts to say that, but a lot of younger people don’t) then you’ll most likely remember days when the television picture was suddenly rubbish.

If you were of enquiring mind, or had a set in your bedroom, or had extraordinarily obliging parents, you most likely twiddled the tuning a bit, only to find a second, seemingly random region knocking heads with your own.

On warm early autumn nights, the service abutting your usual region was clearly foreign – RTÉ, TF1, Dutch and Belgian stations, say. On very sultry nights, they were from further afield – Switzerland, East Germany, the USSR. With freak weather conditions comes freak UHF reception.

People even older than me will remember the summertime smorgasbord of foreign VHF stations that would turn up, often from very far away indeed, but rather than just interfering with your picture as with UHF, usually they’d destroy it completely. No Doctor Who for you tonight.

 

 

November 1947 was a weird month for weather. Whilst there was some snow and sleet across the south of England, the air temperature in the afternoons was well above average for this time of year. That probably indicates how this phenomenon was occuring – a settled band of high air pressure was bouncing the NYPD signals across the Atlantic via tropospheric propagation, right into the path of pictures from Ally Pally.

A Transdiffusion Presentation

Report an error

Author

Sussex Express & County Herald My website Contact More by me

You Say

2 responses to this article

Mr Hoover 21 October 2020 at 4:06 pm

This reception was due to F2 layer radio propagation enhanced caused by high sunspot numbers in autumn 1947,nothing to do with tropospheric, settled weather reception in this case.
The Ally Pally TV signal was received over very long distances.

Joanne 23 October 2020 at 10:50 pm

I used to enjoy DXing in the warmer weather back in the 80s and 90s. From my bedroom in a house on the North East coast of England, on my bedroom colour portable, I could get tv stations from Germany, the Netherlands, Sweden and several regional stations of the Danish channel TV2. The fascination of tuning into these “rogue signals” kind of made up for not being able to enjoy my usual programmes from Tyne Tees and BBC North East and Cumbria.

Your comment

Enter it below