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-   -   Baird Garrick (https://www.vintage-radio.net/forum/showthread.php?t=145778)

beery 18th Apr 2018 1:30 am

Baird Garrick
 
5 Attachment(s)
Hi All,
I've just obtained this Baird Garrick.

There are only a couple of valves present and the tube has been necked.
Also there was a mouse nest in the PSU section at the bottom of the set.

However it is not all bad. The cabinet has survived quite well and still has a good finish. There is no sign of damp (appart from mouse wee). All the electronics seems to be present.

I made a start by removing the mouse nest and cleaning away all the droppings.
The PSU although corroded on top due to the mice, actually looks like new underneath. There are signs that there was once a mains EHT transformer fitted, although there is no socket for and EHT rectifier on the PSU chassis.
I checked the date on one of the electrolytics to be March 1948.

I would apreciate any service info or photos that anyone has. A photo of the back cover could be nice for a start.

Cheers
Andy

rogerdup 18th Apr 2018 7:39 am

Re: Baird Garrick
 
Hi Andy,
The cabinet looks nice. I will follow your restoration of this set when you decide to start on it.
Regards,
Roger

Argus25 18th Apr 2018 8:35 am

Re: Baird Garrick
 
I wonder if the mice ate the speaker cone or perhaps harvested the cone to help make their nest.

Its a great looking TV!

FERNSEH 18th Apr 2018 10:09 am

Re: Baird Garrick
 
4 Attachment(s)
Hi Andy,
Here's some pictures of the chassis assemblies in another Baird theatreland model, the "Lyric".
The Garrick and Lyric TVs were part of a series of models manufactured after WW2. There was also an Adelphi model.
The story goes that J.L. Baird's friend Jack Buchanan financed the TV manufacturing project.

From Helensburgh Heritage:
http://www.helensburgh-heritage.co.u...ird&Itemid=457

DFWB.

FERNSEH 18th Apr 2018 10:25 am

Re: Baird Garrick
 
1 Attachment(s)
A picture of the power supply unit.

DFWB.

Jac 18th Apr 2018 10:52 am

Re: Baird Garrick
 
4 Attachment(s)
Andy,

Please find attached the images I have of a Baird Garrick.
No picture of the back I'm afraid.

Jac

Panrock 18th Apr 2018 4:41 pm

Re: Baird Garrick
 
A rare bird indeed! I will follow with interest.

Steve

mark pirate 19th Apr 2018 7:46 pm

Re: Baird Garrick
 
Glad that the set went to a good home, a very rare set.
I noticed the CRT was necked, by the look of the LOPT it looks to have been shedding hot wax recently, hope it turns out to be OK....
:beer:
Mark

FERNSEH 19th Apr 2018 9:30 pm

Re: Baird Garrick
 
1 Attachment(s)
The CRT is the Mazda CRM121 or CinTel 12MW3A.
The HT rectifier Mazda UU8. RF pentodes Mazda 6F12 = EF91/6AM6.
It's possible the timebase circuits are similar to the pre-war Baird TVs, those pole piece extensions about the neck of the CRT will confirm if that is so.
The timebase valves are likely to be the Mazda 6P28 although it's worth noting that Ambassador employed a similar circuit in the TV2 and the valves employed in that set were two 20P1s.
The revised attachment shows the frame transformer pole pieces.

DFWB.

Argus25 19th Apr 2018 11:26 pm

Re: Baird Garrick
 
1 Attachment(s)
Quote:

The revised attachment shows the frame transformer pole pieces.
That is really interesting. I wonder what the frame linearity was like ? The closest thing I have seen to this are some of the experimental TV deflection systems in Von Ardenne's book (attached image) where there was a picture of a large iron cored pole piece/frame def coil. I guess it makes sense to make the actual coil the frame oscillator too, as it could avoid a frame output and frame oscillator transformer

FERNSEH 20th Apr 2018 12:32 am

Re: Baird Garrick
 
Pre-war Baird TV receivers employed extended frame timebase transformer pole pieces.
Link to the CRT replacement topic in my Baird T23. Post No.33 shows the transformer and it's extended pole pieces.

.https://www.vintage-radio.net/forum/...d.php?t=132064

Unsure if it was Baird Television Ltd or Fernseh AG that had developed this type of timebase generator.

DFWB.

beery 20th Apr 2018 11:07 am

Re: Baird Garrick
 
Hi all,
Thanks for your encouragement.

The speaker cone, yes some of it was found in the mouse nest. I'm not going to try to glue it back together ;)

I had the PSU on the bench last night and sketched out the circuit. It is indeed a UU8 that is required. I hope that's not too expensive.

I had a quick look at the sound receiver, indeed it seems to use 6F12 pentodes and maybe a 6D2 detector. I will trace out the circuit later. Interestingly the sound receiver is powered from the PSU in the radio, so I will probably start with the sound first.

The timebase section is all 4V, so I guess it would be a PEN46 used for each timebase output. I assume the line generator is a T41??
Anyway, a low current 6.3V feed goes to the timebase chassis to provide a 6.3V CRT heater option. This set has a Mullard MW31-14 or MW31-7 (the label is damaged). I think one of the photos of other sets shows this too. I intend to fit an MW31-74, but I need a cavity anode to top cap adaptor. I will place a wanted add for parts required.

About the chassis generally, it looks like an aluminium version of a Baird pre-war chassis. Indeed I think the pre-war Baird TRF unit would fit directly in place of the vision receiver.

More to follow this weekend as I start to draw up the circuits.

Cheers
Andy

Heatercathodeshort 20th Apr 2018 11:19 am

Re: Baird Garrick
 
I have a clip to cavity connector converter you can have FOC. If you would like it, please send me a PM and I will post. John.

FERNSEH 20th Apr 2018 12:52 pm

Re: Baird Garrick
 
1 Attachment(s)
The timebase circuits of the Ambassador TV2.
Line and frame timebases are of the self oscillating type.

The earlier model TV1 employed thyratron oscillators.

DFWB.

FERNSEH 20th Apr 2018 3:17 pm

Re: Baird Garrick
 
1 Attachment(s)
The sync separator in the Ambassador TV2.
The 6F13 can be substituted with a 4volt Mazda SP41.

DFWB.

beery 21st Apr 2018 2:55 pm

Re: Baird Garrick
 
Quote:

Originally Posted by Heatercathodeshort (Post 1036661)
I have a clip to cavity connector converter you can have FOC. If you would like it, please send me a PM and I will post. John.

Thanks John,
I'll send you a PM.

Cheers
Andy

beery 26th Apr 2018 2:21 pm

Re: Baird Garrick
 
5 Attachment(s)
Hi all,
Here are some photos of the TV section.

The mask is completely unuesable, I plan to use the mask from a TV24 for now, but I don't know how to hold the CRT in place as it does not wrap around the bulb of the tube as the existing mask does.
Any suggestions?

The third photo shows a neon regulator an odd thing to find in a TV you might think, but then it is a Baird. However the nipkow disk that should go in front of it is missing :-D

The fourth photo shows the rogue line output and EHT transformer. It looks rather like the lopty from a Baird Townsman, so was it from a Baird repair?

The underside looks fairly straight forward though.

Cheers
Andy

mark pirate 26th Apr 2018 4:18 pm

Re: Baird Garrick
 
Quote:

The fourth photo shows the rogue line output and EHT transformer. It looks rather like the lopty from a Baird Townsman, so was it from a Baird repair?
It looks the same as the one in my T164 portable, definitely a Baird part.
Was it originally mains EHT?
I wonder if you could use webbing straps to hold the CRT in place, as seen on many HMV/Marconi sets?
:beer:
Mark

Jac 26th Apr 2018 4:43 pm

Re: Baird Garrick
 
Quote:

Originally Posted by beery (Post 1038437)
The fourth photo shows the rogue line output and EHT transformer. It looks rather like the lopty from a Baird Townsman, so was it from a Baird repair?

Hi Andy,

The LOPT also looks the same as the one in my Baird T29A.

A mask can be made from MDF material. I did this for a Philips 383A and for a Pye 817.

Jac

beery 29th Apr 2018 10:08 pm

Re: Baird Garrick
 
3 Attachment(s)
Hi all,
Thanks for all your ideas and encouragement.

I'm not quite sure yet what to do about the tube mounting.

Yes, it had mains EHT originally and the mounting points for the EHT transformer etc have been used in the past. For now I will restore it as it is, with a view to converting it back as soon as I know the transformer rating etc.

I spent friday night at my parents house and went hunting for parts.
I now have most of the valves I need and many other parts, some of which are shown in the first photo.
I found 3 UU8 valves!, but only one PEN46 and it does not look too clever.
I did not have any 6F12 valves, so I will have to fit EF91 valves for now, which hopefully won't affect the alignment too much. Luckilly it looks like the RF coils have never been got at and I don't intend to touch them either.
I could not find a 10" speaker unfortunately.

The second photo shows a new MW31-74 CRT. I still need an ion trap magnet for this.

The third photo shows the anode cap adaptor which Heatercathodeshort kindly sent me. This allows me to use a later CRT without changing the anode connector.

Restoration has now started and is continuing on several fronts simultaneously. However, I shall write it up chassis by chassis. The aim is to get the sound working first.

Cheers
Andy


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