Single Channel 405-line Receivers - UK Vintage Radio Repair and Restoration Discussion Forum

Panrock · 13th Sep 2016, 8:49 am

The vast majority of British 405-line receivers, of whatever age, will work off a 'London' (channel 1) signal. However there were also a few 'Birmingham-only' (channel 4) sets made around the time when Sutton Coldfield started up.

Were any 'Holme Moss-only' or 'Kirk O'Shotts-only' (etc.) sets ever made, or did the single channel idea immediately cease when the available channels started to multiply?

Steve

Edward Huggins · 13th Sep 2016, 9:20 am

I think that the convention was that 5 ch sets replaced "dedicated" single channel sets in about 1952, followed by 13 ch in 1955. Edward

brianc · 13th Sep 2016, 9:26 am

Hi Steve
I have a TV12 which is tuned to CH2 with brass slugs in the coils to raise the frequency. In order to change the slugs, the coil cans must be removed and the soldering on them looks the same age as the rest of the set. However, the aerial input socket is labelled "London" so whether it was a prototype or a demo model I have no idea but it was certainly released as a CH2 set.

FERNSEH · 13th Sep 2016, 10:18 am

EMI marketed single channel versions of the 1806 and 1807 models which were designed to receive on other BBC channels. For example the TRF receiver vision and sound unit in the 1807 Alexandra Palace set was modified to receive the Sutton Coldfield transmitter by converting the RF unit to a superhet design.
The SC channel 4 model was recoded as 2807. Another single channel version of the 1807 was the 3707? which was designed for the Holme Moss transmitter.
The mighty console model 1806 like the 1807 employed a TRF receiver unit for AP was later on modified to superhet operation for reception of the Sutton Coldfield and Holme Moss transmitters, these were the models 2806 and 3606 respectively. A model to receive BBC channel 3 was also made, possibly the 4706.
The Marconi version of the HMV 1807 was the model VT53A. The Birmingham superhet receiver was designated as VT73A. Like the HMV 1807 various models were made for other BBC transmitters.

DFWB.

Brigham · 13th Sep 2016, 10:40 am

In the same vein, did anyone make a two-channel set, for London/Birmingham?

FERNSEH · 13th Sep 2016, 11:05 am

Quote:

Originally Posted by Brigham

In the same vein, did anyone make a two-channel set, for London/Birmingham?

Vidor. Models CN370 and CN377 had a two station switch which was situated at the back of the set.

DFWB.

FERNSEH · 13th Sep 2016, 11:47 am

More information about single channel Marconi TVs which are derivatives of the model VT53A = HMV 1807.
VT53A TRF receiver for AP channel 1.
VT76DA Superhet receiver for channel 4 (Sutton Coldfield)
VT86DA Superhet receiver for channel 2 (Holme Moss)
VT96DA Superhet receiver for channel 3 (Kirk o'Shotts)

DFWB.

emeritus · 13th Sep 2016, 12:44 pm

I found the following in my collection of old leaflets (mostly undated) from the early 1950's.

HMV leaflet (possibly July 1952 from the printer's code): as well as (presumably newer) 5 channel sets, others were supplied for a single frequency and had different type numbers accordingly. London, Midlands, Northern, Scottish, and Western. Not all such sets were available for all regions.

McMichael leaflet: while other sets were tuneable to other frequencies, the basic DeLuxe combined TV and Radio receiver was available for London only, but a chassis for other regions was available.

Decca large screen projection TV (40"' x 30"): available as a single sideband model for any specified region, as well as a "High Definition" double sideband model for the London area only. Seems that the double-sideband transmissions provided better quality that a large screen set could make use of. Before reading this thread I had been under the impression that the only TVs designed for DSB were pre-war models.

emeritus · 13th Sep 2016, 5:09 pm

Just found another HMV leaflet, probably from July 1953. Only three single-channel models, the 1851/1806 series that appeared in the 1952 leaflet, and the 1902B series, new in this leaflet. All available for all five regions. All the others are 5-channel models. Extract attached

Panrock · 13th Sep 2016, 6:02 pm

253 guineas... just for a television alone. Strewth !!!

peter_scott · 13th Sep 2016, 6:36 pm

I think my parents first television (Philips 1400A) had plug-in coils to determine its channel 3 reception. So you might say it was single channel, at least as far as the customer was concerned.

Peter

FERNSEH · 13th Sep 2016, 8:25 pm

Quote:

Originally Posted by Panrock

253 guineas... just for a television alone. Strewth !!!

The HMV 1820 was unique in being the largest direct view set available in 1952.
The CRT was an Emiscope 21" round faceplate metal cone type.
The set was fitted with a twelve position turret tuner which was fully loaded with coils for all the five BBC channels.

DFWB.

Aub · 13th Sep 2016, 8:42 pm

Hi All,

When I was a small boy, our TV set was one of those with a sloping corrugated panel, below the screen, through which two edgewise knobs protruded ( on/off/volume and brightness ? ) I think it was a Pye set. The local "teleman", as dad used to call him, built us a converter box which we used for ITV. Does that mean the set was single channel? I can't remember much about the tuning arrangements. The set was replaced in 1964 by a new set, which had a knob with 625 on it, but we still couldn't get BBC2. We didn't get BBC2 until 1971 when we got a new set.

Happy memories!

Aub

FERNSEH · 13th Sep 2016, 8:57 pm

Hi Aub,
It's most likely the set was a Pye V4 which was fully tunable to all the five BBC channels.

DFWB.

AC/HL · 14th Sep 2016, 12:19 am

This is a coil from my junk box, Philips I think, for Holme Moss.
It's on a B9A base. I've no idea which coil it is, I only have the one.

ukcol · 14th Sep 2016, 9:52 am

Quote:

Originally Posted by FERNSEH

The set was fitted with a twelve position turret tuner which was fully loaded with coils for all the five BBC channels.

Was this twelve position tuner capable of band III reception anticipating the arrival of ITV?

FERNSEH · 14th Sep 2016, 10:17 am

Was this twelve position tuner capable of band III reception anticipating the arrival of ITV?

EMI must have considered the tuner not good enough for Band 3 reception and instead offered a replacement tuner which was similar to the 14 position incremental switch tuner that was installed in most HMV and Marconi sets made between 1954 to 1957.
Also, the tuner was positioned at the back of the set, not very convenient for the user so the new tuner was fitted on the front control panel.
The original tuner employed a Z77/6AM6 pentode as the RF amplifier and a B152/12AT7 double-triode as the mixer-oscillator. The Band 3 performance of these valves is not very good. The replacement tuner employed ECC84 and ECF80 valves.

DFWB.

Brigham · 14th Sep 2016, 11:59 am

I take it no-one has a working example of a set fitted with ' an Emiscope 21" round faceplate metal cone type' CRT?

FERNSEH · 14th Sep 2016, 1:35 pm

I did at one time own an HMV 1820 which was equipped with the original metal cone CRT. However, the original Emiscope metal cone CRT soon became obsolete and the recommended replacement was the Mullard MW53-20. EMI issued a service bulletin which gave instructions on how to do the CRT substitution.
I believe at least two HMV 1820 sets are still in existence.

DFWB.

Panrock · 14th Sep 2016, 1:46 pm

What was the EHT on this huge screened set?

13th Sep 2016, 8:49 am	#1
Panrock Nonode Join Date: Feb 2005 Location: Worcestershire, UK. Posts: 2,534	Single Channel 405-line Receivers The vast majority of British 405-line receivers, of whatever age, will work off a 'London' (channel 1) signal. However there were also a few 'Birmingham-only' (channel 4) sets made around the time when Sutton Coldfield started up. Were any 'Holme Moss-only' or 'Kirk O'Shotts-only' (etc.) sets ever made, or did the single channel idea immediately cease when the available channels started to multiply? Steve __________________ https://www.radiocraft.co.uk

13th Sep 2016, 9:20 am	#2
Edward Huggins Dekatron Join Date: Sep 2015 Location: Southwold, Suffolk, UK. Posts: 8,336	Re: Single Channel 405-line Receivers I think that the convention was that 5 ch sets replaced "dedicated" single channel sets in about 1952, followed by 13 ch in 1955. Edward

13th Sep 2016, 9:26 am	#3
brianc Rest in Peace Join Date: Jun 2004 Location: Burghfield, Reading, Berkshire, UK, Posts: 1,055	Re: Single Channel 405-line Receivers Hi Steve I have a TV12 which is tuned to CH2 with brass slugs in the coils to raise the frequency. In order to change the slugs, the coil cans must be removed and the soldering on them looks the same age as the rest of the set. However, the aerial input socket is labelled "London" so whether it was a prototype or a demo model I have no idea but it was certainly released as a CH2 set.

13th Sep 2016, 10:18 am	#4
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Single Channel 405-line Receivers EMI marketed single channel versions of the 1806 and 1807 models which were designed to receive on other BBC channels. For example the TRF receiver vision and sound unit in the 1807 Alexandra Palace set was modified to receive the Sutton Coldfield transmitter by converting the RF unit to a superhet design. The SC channel 4 model was recoded as 2807. Another single channel version of the 1807 was the 3707? which was designed for the Holme Moss transmitter. The mighty console model 1806 like the 1807 employed a TRF receiver unit for AP was later on modified to superhet operation for reception of the Sutton Coldfield and Holme Moss transmitters, these were the models 2806 and 3606 respectively. A model to receive BBC channel 3 was also made, possibly the 4706. The Marconi version of the HMV 1807 was the model VT53A. The Birmingham superhet receiver was designated as VT73A. Like the HMV 1807 various models were made for other BBC transmitters. DFWB.

13th Sep 2016, 10:40 am	#5
Brigham Octode Join Date: Mar 2006 Location: Co. Durham, UK. Posts: 1,117	Re: Single Channel 405-line Receivers In the same vein, did anyone make a two-channel set, for London/Birmingham?

13th Sep 2016, 11:47 am	#7
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Single Channel 405-line Receivers More information about single channel Marconi TVs which are derivatives of the model VT53A = HMV 1807. VT53A TRF receiver for AP channel 1. VT76DA Superhet receiver for channel 4 (Sutton Coldfield) VT86DA Superhet receiver for channel 2 (Holme Moss) VT96DA Superhet receiver for channel 3 (Kirk o'Shotts) DFWB.

13th Sep 2016, 6:02 pm	#10
Panrock Nonode Join Date: Feb 2005 Location: Worcestershire, UK. Posts: 2,534	Re: Single Channel 405-line Receivers 253 guineas... just for a television alone. Strewth !!! __________________ https://www.radiocraft.co.uk

13th Sep 2016, 6:36 pm	#11
peter_scott Dekatron Join Date: May 2003 Location: Edinburgh, UK. Posts: 3,274	Re: Single Channel 405-line Receivers I think my parents first television (Philips 1400A) had plug-in coils to determine its channel 3 reception. So you might say it was single channel, at least as far as the customer was concerned. Peter __________________ http://www.nostalgiatech.co.uk https://www.youtube.com/c/PeterScott/videos

13th Sep 2016, 8:42 pm	#13
Aub Nonode Join Date: Mar 2005 Location: Nuneaton, Warwickshire, UK. Posts: 2,039	Re: Single Channel 405-line Receivers Hi All, When I was a small boy, our TV set was one of those with a sloping corrugated panel, below the screen, through which two edgewise knobs protruded ( on/off/volume and brightness ? ) I think it was a Pye set. The local "teleman", as dad used to call him, built us a converter box which we used for ITV. Does that mean the set was single channel? I can't remember much about the tuning arrangements. The set was replaced in 1964 by a new set, which had a knob with 625 on it, but we still couldn't get BBC2. We didn't get BBC2 until 1971 when we got a new set. Happy memories! Aub __________________ Life's a long song, but the tune ends too soon for us all.

13th Sep 2016, 8:57 pm	#14
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Single Channel 405-line Receivers Hi Aub, It's most likely the set was a Pye V4 which was fully tunable to all the five BBC channels. DFWB.

14th Sep 2016, 12:19 am	#15
AC/HL Dekatron Join Date: Nov 2003 Location: Heckmondwike, West Yorkshire, UK. Posts: 9,642	Re: Single Channel 405-line Receivers This is a coil from my junk box, Philips I think, for Holme Moss. It's on a B9A base. I've no idea which coil it is, I only have the one. Attached Thumbnails

14th Sep 2016, 10:17 am	#17
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Single Channel 405-line Receivers Was this twelve position tuner capable of band III reception anticipating the arrival of ITV? EMI must have considered the tuner not good enough for Band 3 reception and instead offered a replacement tuner which was similar to the 14 position incremental switch tuner that was installed in most HMV and Marconi sets made between 1954 to 1957. Also, the tuner was positioned at the back of the set, not very convenient for the user so the new tuner was fitted on the front control panel. The original tuner employed a Z77/6AM6 pentode as the RF amplifier and a B152/12AT7 double-triode as the mixer-oscillator. The Band 3 performance of these valves is not very good. The replacement tuner employed ECC84 and ECF80 valves. DFWB.

14th Sep 2016, 11:59 am	#18
Brigham Octode Join Date: Mar 2006 Location: Co. Durham, UK. Posts: 1,117	Re: Single Channel 405-line Receivers I take it no-one has a working example of a set fitted with ' an Emiscope 21" round faceplate metal cone type' CRT?

14th Sep 2016, 1:35 pm	#19
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Single Channel 405-line Receivers I did at one time own an HMV 1820 which was equipped with the original metal cone CRT. However, the original Emiscope metal cone CRT soon became obsolete and the recommended replacement was the Mullard MW53-20. EMI issued a service bulletin which gave instructions on how to do the CRT substitution. I believe at least two HMV 1820 sets are still in existence. DFWB. Last edited by FERNSEH; 14th Sep 2016 at 1:42 pm.

14th Sep 2016, 1:46 pm	#20
Panrock Nonode Join Date: Feb 2005 Location: Worcestershire, UK. Posts: 2,534	Re: Single Channel 405-line Receivers What was the EHT on this huge screened set? __________________ https://www.radiocraft.co.uk