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-   -   B&O Capri 606 TV (17") restoration (https://www.vintage-radio.net/forum/showthread.php?t=160135)

staticmind 28th Sep 2019 9:25 pm

B&O Capri 606 TV (17") restoration
 
1 Attachment(s)
Hi,

I recently acquired a Bang & Olufsen Capri 606 TV, 17", from 1960. The set was stored indoors, and it sat unused since at least the late 70'ies or early 80'ies. So it was more or less covered in dust. My plan is to get this TV set working again, but I have by no means any expertise with old TVs - only modern hardware with ICs and such.

It uses a AW43-88 CRT, my particular CRT looks to be the original one from Philips. The glass surrounding the gun looks a bit dark at some parts. The flyback looks visually good. All tubes seem to have an equal amount of dust of them, so they might all be original.
I can see some of the smaller electrolytic caps have leaked, so I would need to replace those before even attempting to power it on.

My question is: I'd prefer to bring the set up on a variac and isolation transformer, but I'm unsure if bringing it up on one can potentially damage anything due to too low voltage for a too long time. Should any tubes generally be removed before attempting this? I have attached the schematic, if it helps.

Thanks.

kan_turk 29th Sep 2019 10:02 am

Re: B&O Capri 606 TV (17") restoration
 
Hi & welcome on board
The approach you suggest is fine - replace any visually defective components and then power up on variac - I’d be inclined to remove EHT rectifier for first power-up - beautiful schematic with a lot of info - best of luck

Rgds
John

Edward Huggins 29th Sep 2019 1:40 pm

Re: B&O Capri 606 TV (17") restoration
 
This looks have a 2 stage AF section with NFB and possibly 2 speakers. I'd be interested to learn how good this sounds when fixed.

staticmind 29th Sep 2019 7:05 pm

Re: B&O Capri 606 TV (17") restoration
 
Thank you both of you.
I'll be sure to remove the DY87 when powering up then - would also be much safer, when there is no EHT.

Edward, it has one speaker only - the 21" one seems to have two. I'll make a high quality sound recording, and post some pictures of the progress.

Right now I have carefully removed the CRT in order to clean the front glass. The previous owner was a bit of a smoker.
The metal screen between the CRT and front glass also badly needs a new sealing to the CRT - the old foam had turned to dust. I'll try with some 3M 4516 vinyl foam tape and see how that works out.

Andy Green 29th Sep 2019 10:49 pm

Re: B&O Capri 606 TV (17") restoration
 
Love to see some ‘before’ pictures

Welsh Anorak 30th Sep 2019 9:54 am

Re: B&O Capri 606 TV (17") restoration
 
I'd be tempted to remove the PY88 and the CRT base while you reform the main capacitors - the variac will make a good job of that. The circuit is typical B&O - looks normal on first sight, but there are some interesting flourishes.
Depending on how dry the set was in storage, it's often an idea to make sure the LOPT is bone dry, either by removal and keeping it in a warm place (not sure how easy this is on this chassis) or else by passing a low current through the overwind - there are details on how to do this elsewhere. LOPTs were certainly a weak spot on the B&O colour chassis as we all know!
The frame stage looks particularly interesting, and I suspect some capacitor replacement will be needed here, but I think it should provide a very linear picture. Some photos would be great so we can see what it looks like.
Good luck!

staticmind 30th Sep 2019 6:41 pm

Re: B&O Capri 606 TV (17") restoration
 
5 Attachment(s)
Thank you very much. The more I look at it, the more I think the set has been used a lot. But it is hard to tell for me what is "tar" and what is actually due to use. The darkened CRT base concerns me a bit, but perhaps it is normal. It's shown in the last attached picture.

The first pic shows what the Capri 606 looked like when it was taken out of storage.
Second pic shows what a bit of cleaning could do.
Third picture shows the flyback - hard to get a good picture, but it seems fine. As it is "16 kV only" I was hoping it would last longer than one designed for larger tubes/anode voltages.
Fourth picture shows the PCBs/chassis - I cleaned a few of the tubes carefully, mainly to get an impression of how much is nicotine and what is dust. :)

The 606 range was the first year the "line automatic" feature was introduced - making horizontal hold adjustment not required anymore.

Welsh Anorak 30th Sep 2019 8:45 pm

Re: B&O Capri 606 TV (17") restoration
 
Firstly, that CRT looks fine to me - the 'silvering' is normal. Also the PCB would look much darker around the valveholders if it was a very high mileage set.
I think some electrolytics are in order - in fact, most of them. However I suspect those green ones will be OK, though someone more familiar with them will give you a definitive answer.
Obviously this was a TV before B&O developed their house style!

Richard_FM 30th Sep 2019 10:51 pm

Re: B&O Capri 606 TV (17") restoration
 
A very neatly laid out PCB inside, rather like some rats nests some sets have inside.

Tazman1966 1st Oct 2019 9:02 am

Re: B&O Capri 606 TV (17") restoration
 
Quote:

Originally Posted by Welsh Anorak (Post 1180204)
...Obviously this was a TV before B&O developed their house style!

I wonder when their style changed and what their contemporaries were like in this era.

Maarten 1st Oct 2019 9:12 am

Re: B&O Capri 606 TV (17") restoration
 
Their schematic style sure changed for the worse at some point, I'm amazed at how clear this one is.

boxdoctor 1st Oct 2019 9:30 am

Re: B&O Capri 606 TV (17") restoration
 
It might be a good idea to slip a small plastic cup or something similar over the end of the anode lead of the DY87 if you intend trying the set without the DY87 fitted.
It would be a pity if the EHT was to jump from the anode connector to the L.O.P.T. windings, and ruin the transformer. Just a thought.
Good luck wih it. B&O's always were one of my favourite makes to work on. Tony.

Welsh Anorak 1st Oct 2019 12:36 pm

Re: B&O Capri 606 TV (17") restoration
 
I think it was around 1970 that thy started to be style conscious. Their TVs looked a bit more upmarket than their contemporaries with controls hidden in drawers that clicked in and out and had a quality feel to them (eat your heart out, G11!). Then their hi-fi became slimmer culminating in the mid-seventies when everything looked sleek and stylish, even the TVs. I'm sure Tim will have his own take on this, though!
They always were nicely made and usually spared a thought for the engineer - as soon as you worked out how they came apart....

Studio263 1st Oct 2019 5:36 pm

Re: B&O Capri 606 TV (17") restoration
 
Quote:

Originally Posted by Tazman1966 (Post 1180275)
I wonder when their style changed and what their contemporaries were like in this era.

It happened in the early 60s as a response to the growing European common market. Realising that there was no longer a place for a small local manufacturer serving just its home country, they decided that they had to export in quantity to survive. The 'Architectural look' developed from this, as part of a strategy to make their models different and attractive in all markets. For a while, essentially the same sets were available in both traditional and modern(e) cabinet styles. Superior quality, technological leadership and carefully selected dealers were part of the same plan, it is summed up by an early advertising slogan used in the UK: 'B&O - for those who consider design and quality before price'.

Although there were a few experiments before, the Beomaster 900K was the first really successful export orientated model, it appeared in 1963. Had the company not pursued this plan the chances are that they would have gone the way of their Danish rivals Arena (who? exactly!), who were once of a similar size to B&O but are now all but forgotten. See also: The British consumer electronics industry.

staticmind 1st Oct 2019 6:40 pm

Re: B&O Capri 606 TV (17") restoration
 
I'm really surprised and amazed about the amount of attention this has gotten. Thank you!

Welsh Anorak, I'll make sure to follow your advice of removing PY88 and CRT socket base as well.
Tony/Boxdoctor: I'll be sure to isolate the anode cap of DY87 so it can't arch anywhere. Good point.

I'd also have to agree with Studio263 on this - one should consider the B&O design that pre-dates the Capri series as something that looks like this: https://www.radiomuseum.org/r/bang_grand_prix_513.html , or with speakers below and on wheels.
In my opinion the only thing that makes the Capri 514, 606 and 607 particularly nice looking is the thing that is always missing: The legs. The 514 with legs is showcased here: https://www.bang-olufsen.com/en/story/93-years-of-magic
I plan to get a wood-turner to make some legs in teak. The threads are already present inside the cabinet. But getting new teak to match teak from 1960 is probably not going to be easy.

To find something which looks more David Lewis/Henning Moldenhawer-like, in my view it would be the Capri Moderne from 1963. It's probably helped a bit by having one of the first "square" CRTs, at least for B&O. I've never seen one in real life though.

Heatercathodeshort 1st Oct 2019 7:01 pm

Re: B&O Capri 606 TV (17") restoration
 
That looks like a Philips LOPT and scan coils. J.

Welsh Anorak 2nd Oct 2019 5:17 pm

Re: B&O Capri 606 TV (17") restoration
 
I take it Arena collaborated with Rank in the Seventies to produce hi-fi systems? They looked nice, but weren't particularly reliable and certainly weren't like B&O!

Welsh Anorak 4th Oct 2019 11:22 am

Re: B&O Capri 606 TV (17") restoration
 
...and I see one is in the Items Offered on this forum! ISTR Arena was the badge on more upmarket Z718 and T20 TVs.

McMurdo 4th Oct 2019 11:51 am

Re: B&O Capri 606 TV (17") restoration
 
there's a comprehensive account of Arena under Rank's ownership on the danish wikipedia site.

staticmind 31st Oct 2019 9:28 pm

Re: B&O Capri 606 TV (17") restoration
 
1 Attachment(s)
Status so far is that
- Glass and CRT cleaned beautifully.
- all electrolytics besides the filter caps have been replaced
- the 0.1 uF from grid of PL36 to ground is replaced (looked wonky and cracked open)
- PL36 is gassy, so will need a replacement for that.
- The 10n across the line cap has separated into two parts (on purpose?)
- The 4,7n cap marked with "23" in the schematic was disconnected. The 1k resistor marked with "22" was replaced with what looks like a 7-10W 1k power resistor. I reverted it back to follow the schematic, but I'm unsure what the purpose of that modification would do. Stability?

Questions:
1) The coil AT4008 comes in a to me quite strange form factor. It is enclosed in a metal tube with a plastic hex nut at the end and with a ~2cm wire coming out of the center of the hex nut. It looks as if it should go somewhere, or should it possibly just float in air? I have attached an image of it.

2) DY87 should be the same as DY86 except for a silicone grease covering for humid conditions - is this just your average silicone grease? When dusting off mine, I removed what might have been silicone grease on the outside.


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