12 or 13 channels?

[Boom]

Most Band III capable vintage sets have 12 channels. Every so often I see one that has 13 channels. What is this all about?

Dave

[Tazman1966]

...and why do Thorn tuners have one of the positions marked 12-13?

[Jonster]

Presumably on the Thorn there were only 12 positions, they must have had some old stock tuners to use up, you would only use one or the other so the dealers fitted a ch13 set of coils into the tuner, or there may have been enough 'swing' in the tuning to cover either.

[Steve_P]

There are 13 channels in Band III.

Cheers,

Steve P.

[Station X]

I thought there were 5 channels in Band I and 8 in Band III making a total of 13?

[Steve_P]

Yes, you're right. 13 Channels in all.

Cheers,

Steve P.

[Boom]

Put it another way. Why should some sets have a channel missing?

[murphyv310]

Hi.
A few dual standard sets used a 12 channel tuner, with the "13" position used to switch to 625.
Also looking on the ITV's lists from the 60's channel 13 was the least used and often a 12 coil was the same as the 13 coil, the pull in range was wide enough using the tuning slug.
On my system here I have ch 1, 2, 9, & 13 all on the one system and it works fine with no cross mod. So on the likes of a Pye VT17 I can select 3 adjacent channels
Cheers
Trevor

[SteveCG]

Why 12 Channels on a UK TV?

Possibly because a Turret Tuner design based on those in the USA/Canada was being used. USA Channels A2,3,4,5,6 (VHF Low Band),
A7,8,9,10,11,12,13 (VHF High Band).

Don't forget that Radio-Astronomy use at Cambridge of UK Channel B6 meant that only 12 Channels were in use in the UK for TV until 1968.

The Thorn 12-13 simply reflected the LO tuning range of the 'fine tune' control.

[Station X]

Maybe it was because 12 divided nicely into 360 deg, but 13 didn't.

[KeithsTV]

According to this website there was also a channel 14 allocated at the top end of band 3.

http://www.pembers.freeserve.co.uk/W...ems.html#Bands

the site also contains a wealth of information on world analogue TV standards.

Keith

[Hybrid tellies]

I can remember tuners that either stopped at 12 or had 12/13. I think ch13 was only used in a few areas of the UK by the BBC from Wenvoe and Belmont and a few relay stations. ITA used this channel mainly for low powered relays in Scotland and Wales with the exception of the high powered transmitters at Selkirk in the Borders area. I wonder if there was some restriction placed on the use of this channel.

[KeithsTV]

Channel 13 was also used for the BBC service from Winter Hill when BBC1 split into Yorkshire and Lancashire regional services.

Keith

[HamishBoxer]

I have read over the years a definitive answer to this if i could remember!Though will try and find out.

David

[Peter.N.]

I can remember there being a station on channel 13. In my workshop then in the Weald of Kent at the bottom of Wrotham hill, I could on occaision get a picture on every band 3channel using a five element beam actually in the workshop, by rotating and changing polarity I could get two on channel eleven, Mendelsham norfolk and southern from Chillerton down, channel 13 had a BBC station on it!

Peter

[SteveCG]

Winter Hill definitely used Channel B12 for its later BBC transmissions.

Quite a few semi-broadband Band III aerials - usually made by Antiference - started to appear on the Lancashire skyline when CH B12 started; ITA was on B9.

Belmont in the East of England and Wenvoe in Wales used Channel 13 for BBC transmissions.

Happy Days!

[Hybrid tellies]

Originally Posted by KeithsTV

Channel 13 was also used for the BBC service from Winter Hill when BBC1 split into Yorkshire and Lancashire regional services.

Keith

No BBC1 was on ch12 from Winter Hill and at a slightly higher power than Granada. Closer to home when BBC Wales opened from Wenvoe on ch13 quite a few people could not receive it becuase there tuners would only go up to ch12. I heard it caused a bit of an upset in parts of South Wales.

[KeithsTV]

Having checked my sources I stand corrected. I think my brain was suffering from Tea deprivation at the time and was mentally adding 1 to the channel numbers.

Keith

[Brigham]

Originally Posted by murphyv310

On my system here I have ch 1, 2, 9, & 13 all on the one system and it works fine with no cross mod. So on the likes of a Pye VT17 I can select 3 adjacent channels
Cheers
Trevor

Sorry to drift off-channel a bit, but do you mean that you can 'turn over' between two programmes, just like 'real life'? How do you combine the two signals? Do you need a set with seperate band I/III aerial sockets? I've been wanting to switch between Doctor Who (Ch.5) and Orlando (Ch.8) for years.

[Hybrid tellies]

Originally Posted by KeithsTV

Having checked my sources I stand corrected. I think my brain was suffering from Tea deprivation at the time and was mentally adding 1 to the channel numbers.

Keith

I get many moment like that,due to caffein and nicotine withdrawel symptons. I suppose if they had not switched over to 625 in 1969 and the 405 service had contined to expand then I think ch 13 would have been used more. Like ch12 it was one of the clearer B3 channels suffering very little from co channel problems and being near the top of the B3 spectrum seemed to suffer far less from electrical interference problems.