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-   -   Philetta BD 244U (https://www.vintage-radio.net/forum/showthread.php?t=161459)

Cathode Ray 17th Nov 2019 2:34 pm

Philetta BD 244U
 
Hello again forum!

Anyone familiar with the Philetta, a little German gem... ?

I have just bagged a Philips Philetta BD 244U, it's in the post as I type. I just I can't seem to resist small VHF units.

Upon looking for a manual, I can only find the 254U. How similar are these radios? Will the 254U manual be sufficient for restoration?

Mucho thanks,

PS, any tips on this compact radio area appreciated.

ms660 17th Nov 2019 3:00 pm

Re: Philetta BD 244U
 
Quote:

Originally Posted by Cathode Ray (Post 1192315)
Upon looking for a manual, I can only find the 254U.

Not a very good copy I'm afraid:

https://www.doctsf.com/documents/aff...9285&num_fic=1

Lawrence.

ms660 17th Nov 2019 3:33 pm

Re: Philetta BD 244U
 
Here's a better one:

https://elektrotanya.com/philips_bd2...wnload.html#dl

Lawrence.

ronbryan 17th Nov 2019 3:45 pm

Re: Philetta BD 244U
 
I think the difference between BD244U and BD254U is just in the detail of the UL41 output valve tone control stage. The 244U has a single 470pF capacitor in the negative feedback between anode and tone control, the 254U has a 'T' network of two series capacitors and a resistor to ground. My 244U seems to have been manufactured with the 254U tone control circuit anyway.

Problems that I am aware of include a burnt out 10k screen grid resistor to the UCH81, leaking ERO paper capacitors and background hum. The 100uF + 50uF smoothing capacitor may need replacing to reduce ripple on the HT and the three terminal (screened) audio coupling caps can be replicated by fitting earthed copper slug tape around the replacement axial component.

I choose to run my set on a 220V AC supply to reduce the heat build-up in the small cabinet, as there is no 240V option.

Good luck with the postal system - it can result in the chassis breaking away from the bakelite fixing pillars in the cabinet.

Ron

Cathode Ray 17th Nov 2019 6:26 pm

Re: Philetta BD 244U
 
Thanks Lawrence and Ron!
This is a great start.

The sender has double boxed it for me, so hopefully it will arrive in one piece.

The last two Radios (Murphy A372's) I received managed to survive the journey, but only due to good packaging.

Fingers crossed!

David G4EBT 17th Nov 2019 7:28 pm

Re: Philetta BD 244U
 
5 Attachment(s)
Back in 2016 I bought a Philetta 254U with a view to restoring it. I restored the cabinet, and as the service data I found on internet was fairly illegible, I re-drew it. It's in 2 parts - LH and RH, which I've attached below in case it might be of help. The above chassis layout was also illegible, so I re-drew that too, which I've attached. I found the circuit confusing as to how the power input should be configured for either 220 or 110V input. See pic 4.

I was initially confused about the three-wire capacitors, of which there are several, but the third wire is simply a shield. Whether or not that's strictly necessary I couldn't say. I looked at several restorations I found on internet, one of which highlighted which caps ideally need to be changed. The underside of the chassis has a high density of components and will be a challenge to work on.

I never got round to restoring the electronics on mine, because fortuitously, a forum member who lives in Spain was keen to find one, so I sold it to him. A radio pro there restored it to working order for him, which - when I learned how extensive the restoration had been, frankly, it was beyond my competence, both technically and from a dexterity aspect. When restored, it worked a treat and as far as I know, is still giving good service.

I hope the attachments below, though for the 254U, might be of some use.

Good luck with it.

ms660 17th Nov 2019 9:14 pm

Re: Philetta BD 244U
 
Quote:

Originally Posted by David G4EBT (Post 1192439)
I found the circuit confusing as to how the power input should be configured for either 220 or 110V input. See pic 4.

I think the manufactures schematic is correct for the voltage selector in the 4th picture.

Lawrence.

Cathode Ray 17th Nov 2019 10:14 pm

Re: Philetta BD 244U
 
Many thanks David, this is wonderful to have, it will surely make life a little easier for me.

I haven't yet seen a component layout diagram anywhere, for any Philetta version.
Perhaps the Philips diagram artists found it too complicated to draw!

unitelex 18th Nov 2019 12:05 am

Re: Philetta BD 244U
 
UL41 -You may already be aware of this, if so apologies, otherwise you might want to check the leakage on this valve, it has a bit of a reputation.

https://www.vintage-radio.net/forum/...ad.php?t=40363

If you find evidence of the leakage problem, good replacement UL41's are in limited supply but apparently there is hope with this thread:

https://www.vintage-radio.net/forum/...ad.php?t=42302

Chris

Cathode Ray 20th Nov 2019 10:47 am

Re: Philetta BD 244U
 
Hi Chris, thanks for the links... hopefully it will be ok but good to know there is a recovery option, even if somewhat dangerous!

Regards
Ray

Cathode Ray 22nd Nov 2019 8:12 pm

Re: Philetta BD 244U
 
4 Attachment(s)
Well I'm happy to report safe delivery.
Double boxing did the trick.

This radio is even smaller that I had imagined, a nice surprise indeed!

Photos below show the state on arrival, not too bad really and I'm glad to see a nice layer of dust and the original German two prong mains plug and flex... nobody had been inside this for quite some time :thumbsup:

It's missing one knob, but it appears to be a dummy knob, I don't see any pot or shaft to mount it. I have a post in the parts wanted section looking for a replacement, should be a standard Philips I suspect.

ronbryan 22nd Nov 2019 8:58 pm

Re: Philetta BD 244U
 
The missing knob should operate the tone control, its shaft is concentric with the volume pot. Your photo of the set internals shows that the original dual pot is fitted.

Ron

Cathode Ray 23rd Nov 2019 12:03 am

Re: Philetta BD 244U
 
Quote:

Originally Posted by ronbryan (Post 1193720)
The missing knob should operate the tone control, its shaft is concentric with the volume pot. Your photo of the set internals shows that the original dual pot is fitted.

Ron

Indeed it does Ron, stripping it down now and I can see the spindle is dual.

Several cracked capacitors spotted and a few blackened resistors, but no show stoppers yet.

The absence of a component layout diagram is making this slow work :-]

Cathode Ray 2nd Dec 2019 9:57 pm

Re: Philetta BD 244U
 
1 Attachment(s)
Hi folks,

I beleive these NTC resistors are bad, the circuit shows them as NTC 220 and 240 Ohms. But they are reading 2.6k and 8.8k respectively, even when heated to 100deg they only drop to about 50% of their ambient values.

Any advice on sourcing replacements?
The manual doesn't provide a wattage rating.

These are in series with the heaters for the UF89 and UY85.

The series dial lamps are also across the 240 Ohm one.


edit: Nothing jumping out at me on the web, I'm wondering if I can just use lower value 'normal resistors' and accept a slow warm up time...???

ms660 2nd Dec 2019 10:21 pm

Re: Philetta BD 244U
 
I would have thought that was about right, especially for the one across the scale lamps, as that one only has any significant purpose when any of the scale lamps go open circuit, if you do the ohms law for their respective hot values given in the schematic you will find that everything tallies up voltage drop wise for the dropper resistors and heater string for the mains voltage selected (the resistance given for the one across the scale lamps being the hot resistance with one or both of the scale lamps open circuit)

For instance look at the hot and cold resistances for the VA1009, VA1010, VA1011 etc here for 100mA series heater chains:

http://www.electrojumble.org/DATA/Mu...o%20VA1040.pdf

Lawrence.

Cathode Ray 2nd Dec 2019 10:27 pm

Re: Philetta BD 244U
 
Ah ha! thanks Lawrence, indeed they don't 'look' fried at all.
I shall leave them alone so, and I'm glad I asked.

Cheers!

ray

Cathode Ray 5th Dec 2019 2:24 pm

Re: Philetta BD 244U
 
1 Attachment(s)
Any thoughts on this silver mica poly, its buried deep so hard to remove. But does that poly case look cracked ?

cathoderay57 5th Dec 2019 3:47 pm

Re: Philetta BD 244U
 
Hi Ray, the clear plastic casing of these polystyrene caps often crazes with age and heat and in principle the cracks could let moisture in and change the value. However, I've usually found them OK. As it is so hard to get at without causing collateral damage I'd leave it alone and see if the set performs acceptably. If you find a fault that you can blame it for then, by all means, have a go! Cheers, Jerry

Cathode Ray 5th Dec 2019 7:36 pm

Re: Philetta BD 244U
 
Cheers Jerry,
Yes that's probably the best way to go, I dont fancy removing it unless necessary.

Thanks

Cathode Ray 6th Dec 2019 9:52 pm

Re: Philetta BD 244U
 
1 Attachment(s)
Well folks, its working a treat.
All bands tuning in well, FM is nice and mellow.

Rustoleums Antique Cream did the job for the case.
Rear knobs are 3d printed then sprayed cream.

About 15 components needed replacement, mainly caps and a few resistors.
Valves were all good, lucky me.
Original flex is in good shape so I'll keep it.
Toothpaste polished up the perspex and removed light scratches.

All in all a nice little set.

Thanks for the help👍


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