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B&W TV Baird Monochrome TV models from circa 1957 to 1980

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Captain Peacock
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Well finally, here it is - about as complete as I can make it with the service manuals & memories I have. Much grateful thanks to Steve Webb his invaluable help. Any additional info/corrections would be welcome. I tried to post this as a PDF but apparently PDFs are not allowed.

 

Baird Monochrome Receivers from 1956/7 to 1980

380 Series

405-line Band I/III 14-inch (MW 36-44?) or 17-inch (MW43-69?) 70-degree deflection mono CRT.

Some models had F.M. radio reception as well. A 5-amp 2-pin reading lamp socket was provided on the back of all 380 series models: apparently, this was all the rage at the time and certain EKCO models were fitted with them as well. Available to buy or rent circa 1957.

380 14” TV-only table model in walnut cabinet with a ‘forward tilt’ front.

382 14” table model with F.M. radio facility in a lighter-coloured walnut cabinet.

390 17” TV-only table model in similar (but larger) cabinet design to the 380 set.

392 17” table model with F.M. radio in similar (but larger) cabinet to the 382.

394 17” TV-only full-height console model with double folding doors.

396 17” full-height console model with double folding doors and F.M. radio in same cabinet as the 394 model.

398 17” ‘contemporary’ (colonial-style) cabinet with F.M. radio. Looked like a large radiogram but with a TVscreen.

 

400 Series

405-line Band I/III, 17-inch (AW43-80) or 21-inch (AW53-80) 90 degree deflection mono CRT

402  17” table model

404  17” table model with FM radio

406  17” table model with doors

408  17” Contemporary cabinet with FM radio & twin speakers

410  21” Console cabinet with FM radio & twin speakers

 

420/440 Chassis

405-line Band/III 17 (AW43-80) or 21 inch (AW53-80) mono CRT

420  17" TV only table model

440  17" TV only table model

 

460 Chassis

405-line Band I/III 17 and 21-inch sets with AW43-80 or AW530-80 CRT and PL36 line output valve.  Some models had FM radio facilities, others didn’t. No further information available.

 

480 Chassis

Two versions were available: all except the 486 and 490 models were 405-line Band I/III TV only whereas the 486 and 490 models were fitted with 3-channel FM radio as well (Home, Third and Light programmes) probably accessed via the turret tuner and had the suffix FM added to the model number on the back. A simple, plug-in wired remote control unit was also available, allowing channels to be selected via a 10-position slide switch. A five-position sound volume switch was also provided on the RCU and this remote unit could be bypassed by a switch inside the set.

Models 486 and 490 had motorised channel change and the option of a retro-fit simple, wired remote control unit and were for AC mains only operation. All other models were AC or DC mains compatible.

482  19” 405 Line Only table model with contemporary cabinet with controls mounted below CRT.

484  19” 405-line only wrap-around (curved?) table model with controls below CRT

486  19” 405-line only consolette model with motorised tuning (a-la Ferguson 705T) with main controls & speaker mounted to the right of the CRT. Also had FM radio fitted and optional simple remote control unit available.

488  23” contemporary design table model with main controls below CRT

490  23” 405-line only deluxe full-length console model with full-length folding doors, FM radio and motorised tuner. Optional simple remote control unit available.

492  19" 405 Line Only table model with wrap-around (curved) cabinet with main controls below CRT.

496  23” 405 Line Only deluxe consolette model with curved (sliding?) doors.

 

600 Chassis (405-line only from new but ready for 625-line conversion kit to be retro-fitted at a later date)

602  19" 405-line table model (released October 1962)

604  19” 405-line table model (released October 1962?)

606  23” 405-line table model (released October 1962?)

608  23” 405-line table model (released October 1962?)

610 19” 405-line table model (released May 1963?)

612 23” 405-line table model (released May 1963?)

 

620 Chassis - Dual Standard with valve tuner & IF strip.

(Suffix S models required a UHF tuner to be fitted for UHF reception, suffix D models had one already fitted and could receive UHF stations (BBC2 only until November 15th 1969) from leaving the factory ‘out of the box.’

622  19” Dual Standard table model with plastic moulded implosion guard

624  19” Dual Standard table model with flat glass implosion guard

626  19" Dual Standard table model with flat glass implosion guard & chrome plated CRT & cabinet front surround.

628  19” Dual Standard table model with bow-fronted cabinet with curved armoured glass implosion guard. Controls on right of CRT, speaker on left.

630  23” Dual Standard table model with plastic implosion guard.

632  23” Dual Standard Consolette table model with double folding doors and plastic implosion guard.

634  19” Dual Standard with plastic implosion guard (for use with Relay Distribution services only).

636  23” Dual Standard with direct vision CRT (A59-11W?) (for use with Relay Distribution services only)

638  23” Dual Standard model specifically for schools with lockable doors & mounted on wooden stand with castors. Not sure if it had plastic or glass implosion guard.

640  19” Dual Standard table model with plastic moulded implosion guard. Similar to model 622 in appearance.

642  19” Dual Standard table model with bow-fronted cabinet and plastic moulded implosion guard. Controls on right of CRT, speaker on left. Similar to model 628 in appearance.

644  23” Dual Standard table model with direct vision CRT (A59-11W?)

646  23” Dual Standard Consolette cabinet with plastic implosion guard & double folding doors (similar to model 632)

648  23” Dual Standard full-height dark wood console cabinet with double folding doors & direct vision CRT (A59-11W?)

650  19” Dual Standard table model in light walnut cabinet and fawn/cream coloured tube surround & flat glass implosion guard. The Baird 620/640 service manual does not list the 650 and 652 models, but I have very clear memories of the 650 in particular which was quite a handsome-looking set.

652  23" Dual Standard table model with similar cabinet design as the 650?

I believe there were also models 654 and 658 which may have been the consolette and full console versions of the 650/652 as per models 646 and 648 but I have no information on these models - if they ever existed!

Additional Notes:

As the fittings and approximate dimensions for the original valve rotary UHF tuner fitted in the 620 series were the same as those for the transistorised rotary UHF tuner fitted in the 660 series, a transistorised UHF tuner could be retro-fitted to the 620 series by a) fitting a 27K 3 Watt resistor in series with the main HT feed wire that originally went straight onto the valve tuner but instead connected via the 27K series resistor onto the power input tag of the transistorised tuner and b) connecting a 27 ohm 5W wirewound resistor across the two (now redundant) valve UHF tuner heater feed wires to 1) maintain the continuity of the series heater chain and 2) absorb the extra voltage applied to the heater chain that was formerly taken up by the two UHF tuner valves (PC86 and PC88). This transistorised tuner upgrade considerably improved UHF signal sensitivity on the 620 series.

Furthermore, as the unit housing the VHF & UHF tuners, aerial & mains input sockets and customer controls was completely pluggable via P3, P4/P5 and P6, an unofficial ‘homebrew’ remote control facility could be added to the 620 series by making up three extension leads and connecting them in place of the three plugs (P3, P4/5 and P6) from the internal tuner assembly onto the main chassis & IF/sound & vision PCB inside the set. These leads connected to a separate tuner/controls assembly from say a scrap 620 series TV. As the mains feed and high DC voltages were present on the remote unit (and the chassis was ‘universal’ meaning it could be live if the mains was connected ‘the wrong way round’), for safety reasons, the remote tuners and control unit must be housed in a suitable well-insulated (and vented) container.

I made up one of these units in a stout wooden box and it worked very well: the only downside being a small-to-moderate loss of contrast due to the long length of the IF signal lead (P3) from the remote VHF tuner assembly to the IF/signal PCB inside the set. However, where I lived was a strong UHF reception area and even with this loss of contrast, there was still plenty of contrast left to compensate for the loss – particularly after I retrofitted a transistorised UHF tuner. This mod could also be applied in a similar fashion to the 67x and 68x models, but not to the 66x models as these had a hard-wired mains lead.

 

660/670/680 Chassis

Dual Standard 19 inch (A47-11W), 20 inch (A50-120W) (680 series only) or 23 inch (A59-11W) direct vision monochrome set with either valve IF strip and transistorised UHF tuner with PCL84 video output valve (early versions of models 661, 662, 663, 664 and 665 only) or transistorised IF strip & UHF tuner with PFL200 video output valve.

The 660 & 670 series were fitted with either a 19” (A47-11W) or 23” (A59-11W) direct vision CRT. 68x models were fitted with either a 20” (A50-120W) or 23” (A59-11W) direct vision CRT. Why the 24” CRT (A61-120W) was never fitted in the 68x models remains something of a minor mystery.

As far as I am aware, all 66x & 67x models were factory-fitted with a rotary UHF tuner, but the 68x models had a 4X push-button UHF tuner instead, either horizontally or vertically mounted depending on the model number (see below)

The 660 range came in six variations:

1) TV only with valve IF strip (early versions of models 661-665 only).

2) TV only with transistorised IF strip (later models of 66x, 67x and 68x series.

3) VHF only with FM radio (model 677 only)

4) 670 series TV only with VHF & UHF reception (671, 672, 673, 674, 675 and 676 only)

5) 680 series which came in TV only (681 ,682, 683, 685) and push-button UHF tuner

6) TV with FM radio and both VHF and UHF TV reception supplied as standard (687, 688 only).

All 660 models had ‘Direct Vision’ CRTs (A47-11, A59-11W or A50-120W in the 681, 682 and 15 models).

All 66x model numbers were fitted with a hard-wired mains lead soldered directly onto the on/off switch on the tuners/control unit, but 67x & 68x models were fitted with a detachable, non-reversible 2-wire mains lead with a male 2-pin mains socket on the back into which fitted a female mains plug identical to that used on the 620 models.

There were four additional 660-chassis model numbers that were only obtainable from Baird distributors: these being models 11, 12, 15 and 16. Details below. Radio Rentals  acquired a few of these over the years and I worked on a couple whilst working at RR in 1973.

There were four versions of tuner/controls assembly fitted:

1) VHF only with F.M. radio (model 677),

2) Rotary UHF tuner above VHF tuner, (all 660/670 models except model 677)

3) 4X push button UHF tuner mounted vertically above the VHF tuner (683, 685, 688 and model 16)

4) 4X push-button UHF tuner  mounted horizontally below the VHF tuner. (681, 682, 687 and model 15)

There were three different types of fully interchangeable UHF tuner used: these being fitted with:

1) Mullard transistors,

2) Fairchild transistors, 

3) Manufactured by R & E Hopt KG

660 Model Numbers (in release date order)

661  19” Dual Standard table model with wooden cabinet & green leather-cloth front panel. Rotary UHF tuner.

662  19” Dual Standard table model with grey moulded plastic front panel & CRT surround. Rotary UHF tuner.

663  23” Dual Standard table model (23-inch version of model 661?) Rotary UHF tuner

664  23” Dual Standard consolette model in wooden cabinet with sliding tambour doors. Rotary UHF tuner.

665  23” Dual Standard full-height console model in highly polished wood with folding doors. Rotary UHF tuner.

671  19” Dual Standard table model with wooden cabinet. Rotary UHF tuner.

672  19” Dual Standard table model with a grey plastic & silver front.  (similar to model 662) Rotary UHF tuner.

673  23” Dual Standard table model in wooden cabinet. 4X push-button UHF tuner (vertically mounted).

674  23” Dual Standard table model with grey moulded plastic front (same as 672 but 23 inch) Rotary UHF tuner.

675  23” Dual Standard consolette model with wooden cabinet & tambour doors. 4X push-button UHF tuner (vertically mounted)

676  23” Dual Standard full-height highly polished console cabinet with folding doors. Rotary UHF tuner.

677  19” VHF (405-line only) table model in wooden cabinet with FM radio reception. No UHF tuner fitted in factory.

11    19” Dual Standard table model with wooden cabinet & white slotted speaker grille. Rotary UHF tuner (only available from Baird distributors).

12    23” Dual Standard table model as per model 11 but 23-inch CRT. Rotary UHF tuner (only available from Baird distributors).

681  20” Dual Standard table model with wooden cabinet. 4X push-button UHF tuner horizontally mounted.

682  20” Dual Standard table model with cabinet similar to 672 but with 4X push-button UHF tuner (horizontally mounted)

683  23” Dual Standard table model in wooden cabinet with 4X push-button UHF tuner vertically mounted

685  23” Dual Standard consolette model with sliding tambour doors & 4X push-button UHF tuner vertically mounted.

687 19”  Dual Standard table model in wooden cabinet & equipped with FM radio and 4X push-button UHF tuner (horizontally mounted).

688  23” Dual Standard table model in wooden cabinet & equipped with FM radio and 4X push-button UHF tuner (vertically mounted).

15    20” Dual Standard table model in wooden cabinet with white slotted speaker grille and 4X push-button UHF tuner (horizontally mounted). Only available from Baird distributors.

16   23” Dual Standard table model in wooden cabinet & white slotted speaker grille. 4X push-button UHF tuner (vertically mounted). Only available from Baird distributors.

There was at least one additional schools model but the model number is not known.

There may also have been a push-button UHF tuner version of the full-length console model 676 which, logic would suggest, would be the model 686: but I can find no reference to this model.

 

Thorn Monochrome 1400 Chassis (Yuk! Horror! FX: buzz, crackle, pull, roll…) (A50-120W or A61-120W CRT)

8645 16” Dual Standard ‘Portable’

8691 20” Dual Standard

8693 24” Dual Standard

8694 20” Dual Standard

8695 24” Dual Standard

 

Thorn Monochrome 1500 Chassis (A50-120W or A61-120W CRT)

8800 20” Single Standard 625  UHF

8801 24” Single Standard 625  UHF

8802 20” Single Standard 625  UHF

8803 16” ‘Portable’ Single Standard 625 UHF

8804 24” Single Standard 625  UHF Posh Wooden Consolette Cabinet

8807 20” Single Standard 625  UHF

8808 24” Single Standard 625  UHF

 

Thorn 1592 Mono Chassis

One model was encountered with a 20” screen.  Not sure if RR ever supplied any sets with the BRC 1600 mono chassis in.

 

 

 
Posted : 19/12/2023 12:21 pm
slidertogrid
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It is interesting to see how the models evolved I had a DER set with a Thorn chassis 405 only 17" screen, looked like a 800 chassis ? I think DER destroyed their sets when they came to end of life so it may have been a set that was 'liberated'... The only Baird ex rentals I remember seeing were colour. Did RR also destroy ex rental models in the earlier days? 

 
Posted : 19/12/2023 2:02 pm
Captain Peacock
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From memory they did: when I was at RR in 1973, all sets older than the 660 series were sent to Bradford works for scrapping: but as you say, the odd set was er, 'liberated' from being dropped down a disused mineshaft or used for landfill. Such a pity as some of the 620 series were in beautiful cabinets (e.g. the 648 model) and some of those came back from rental in almost mint condition! i wish I'd liberated one of those! However, I was more than happy with my 626 model that was 'swapped' for a Ferguson 705T which had a tube in that was so flat even with the curtains drawn, it was difficult to see the picture.

I had that 626 from 1973 until 1996 - and the CRT was still very good even then! It was a Mullard AW47-91 with a yellow label which were noted for their hard vacuums.

 
Posted : 20/12/2023 12:27 pm
RichardFromMarple
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I heard RR liked to scrap old sets as they considered a sold set a loss of a customer. I assume they didn't not even sell them through trade only disposal dealers.

It's possible some older sets were stolen & never recovered, or else stayed on rental & never returned.

I've heard of some rental companies offering older or small sets to customers for a token amount or even for free as long as they understood they were responsible for getting it repaired.

 
Posted : 20/12/2023 10:47 pm
Doz
 Doz
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There was one rental client who's records had never moved over when the rental system was computerised in the early 90's... I got a call in the mid 90's as there was no picture. I couldn't find the records, but the business owner checked the old record, and her account was up to date... and the set? A 22" combined signals G8! It was replaced with a nice new Sanyo! Once we dug the old record cards out, it had been in in 1980 for a loptx and tripler, and never seen again. Sadly it was scrapped off at that point, the CRT being absolutely shot, although I did get it going. Paid for itself a few times over!

 
Posted : 21/12/2023 8:30 am
slidertogrid
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@richardfrommarple One of our local independent dealers did exactly that, with Mono rentals around 1981. They offered the customer an upgrade to a second hand colour set for a small increase in rental or they could keep the mono set free but it would no longer be maintained. It seemed an odd decision to me. Some customers must have upgraded though as I ended up buying a van load of returned sets which I sold easily so there was still a market for them. 

I had a few mono rentals right into the 90's the very last being modified colour sets converted to mono. 

 
Posted : 21/12/2023 10:58 am
colourstar
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A very interesting and comprehensive list Captain Peacock. I've always liked the styling of Baird sets and have owned quite a few. Here are a few photos to add some actual examples of sets...

Baird M680
Baird M661
Baird 604
Baird

On the left is an M68x (there's a staple right through the model tag!) It's essentially the same as the M661 next to it, except that it has a pushbutton UHF tuner and the IF panel is hybrid. Next along is a model 604 with it's rather unusual styling and lastly is an early dual standard which I used to own but no longer have. The first three sets are all in my current collection.

Steve

 
Posted : 21/12/2023 11:25 am
Till Eulenspiegel
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Baird TV sets were available to independent dealers through Baird Television Distributors Ltd. Model type numbers prefixed with the letter M.

With regard to Baird monochrome receivers. Were any very late production 1500 series models equipped with the transistor frame timebase?

This question might apply to DER mono sets also.

I was buying new Ferguson 1500 series sets as late as 1977 but none had the transistor frame timebase.

Thorn 1500 Transistor  FTB

Till Eulenspiegel. 

 
Posted : 21/12/2023 5:00 pm
RichardFromMarple
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Posted by: @slidertogrid

@richardfrommarple One of our local independent dealers did exactly that, with Mono rentals around 1981. They offered the customer an upgrade to a second hand colour set for a small increase in rental or they could keep the mono set free but it would no longer be maintained. It seemed an odd decision to me. Some customers must have upgraded though as I ended up buying a van load of returned sets which I sold easily so there was still a market for them. 

I had a few mono rentals right into the 90's the very last being modified colour sets converted to mono. 

I've heard of decolourised sets being offered when large screen B&W sets became rare, usually the colour crystal was disconnected.

 

 
Posted : 21/12/2023 10:13 pm
colourstar
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A couple more photos- neither of these sets are mine (although I wish they were!) The one on the right is an M642.

Baird Mxxx
Baird M642
 
Posted : 21/12/2023 10:15 pm
Nuvistor
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@colourstar I like the style of the M642.

Frank

 
Posted : 21/12/2023 11:01 pm
slidertogrid
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@richardfrommarple Yes it was best to link the crystal to prevent any chance of spurious oscillation producing any patterns. I didn't see any but we didn't want to take any chances. Some of our older mono customers were pleased to be able to have a remote control set at last!  

My Mate Mick had a M652 or similar in his collection a few years ago.  I could have bought it, I wish I had now! I only saw one or two back in the day ISTR they worked well with very little attention needed. The chassis layout had a passing resemblance to the rank A640 I think... 

 
Posted : 22/12/2023 6:51 am
RichardFromMarple
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@slidertogrid 

I can't think of many B&W sets with a remote other than ones with the higher spec Phillips TX chassis.

 
Posted : 22/12/2023 4:15 pm
Captain Peacock
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Posted by: @colourstar

A couple more photos- neither of these sets are mine (although I wish they were!) The one on the right is an M642.

-- attachment is not available --
-- attachment is not available --

Thanks for the appreciation and my work was really a labour of love and thanks too for the snaps Colourstar: boy, do they bring back some memories! I liked the 680 series cabinets, but the 661 (and its 23 inch equivalent - the 663) was the least favourite design for me - along with the 642 where the curved front never did it for me! However, what is one man's poison...

 

 
Posted : 28/12/2023 12:53 pm
Nuvistor
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Some information about Baird and Radio Rentals.

https://blog.scienceandmediamuseum.org.uk/tv-in-bradford-part-2-radio-rentals/

 

Frank

 
Posted : 30/12/2023 11:49 am
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