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-   -   Philips T-Vette (https://www.vintage-radio.net/forum/showthread.php?t=10803)

Kat Manton 24th Aug 2006 12:25 am

Philips T-Vette
 
Hi,

A while ago I was offered an unidentified dual-standard portable set. No mention of make/model has been made apart from a rough description by email. But, after a spot of google image-searching for pictures of portables, I strongly suspect it's the Stella version of the Philips T-Vette. It'll be interesting to see if I'm right when it's dropped off on Friday... ;D

As I'm unfamiliar with the set, I'd be interested in any comments, stock faults, etc., which anyone knows about. Even if I've misidentified the set this will still be of interest as I might pick up a T-Vette anyway.

Regards, Kat

Steve_P 24th Aug 2006 12:46 am

Re: Philips T-Vette
 
These are Dual Standard Portables, with only one valve (EHT Rectifier - DY51) oh, and a tube of course. They were made by Philips and sold under the Stella name.

The tube heaters tend to go open circuit, and the system switch sticks. Check the mechanics carefully and dont start it up for the first time with the tube base on. The Power Supply stages tend to go a bit high, especially the tube voltage. Which is why the heaters go pop.

Nice sets when they work (Aren't they all) but can be nasty when they don't!

Cheers,

Steve P

Kat Manton 24th Aug 2006 2:27 am

Re: Philips T-Vette
 
Hi Steve,

Thanks for the tip - that could make the difference between a "Wanted - CRT" posting and a set perhaps only needing something more readily available :)

I'll mention this in an email, suggesting not to try the set out after retrieval from a loft before delivery. Whether it's a T-Vette or not, that's possibly a good suggestion.

I like this forum; there seems to be a good chance someone here will know something about anything :)

Cheers, Kat

Paul_RK 24th Aug 2006 7:54 am

Re: Philips T-Vette
 
Hi Kat,

As though you haven't enough encounters with their kind in the pipeline, there are a couple of AF115s and an AF117 in residence ;) One of the 115s was responsible for sudden complete lack of signal on one of my three T-Vettes. The sets have been remarkably free of trouble otherwise.

Paul

Focus Diode 24th Aug 2006 10:32 am

Re: Philips T-Vette
 
I obtained a mint condition Philips model years ago and is the only set I have that's never had a component replaced. Has very little use though.

Watch out for dry joints, these can cause peculiar effects such as frame collapse on a blank channel and full scan on a locked station! (Dry joint on frame output transistor).

Also watch the rear three pin plug- a poor design akin to a 3-pin plug without a cord grip. The wiring can break easilly.

What I find irritating is the single line hold control which needs re-setting when selected between 405 and 625. Does anyone know if there's a pre-set control internally? Both my examples are like this.

The ability to replay images from a VCR is a complete write off ,(don't know of any mods here), but stable with non Macrovision protected DVDs.

I have another example which suffers from low gain and frame cramping but havn't got round to looking at it yet.

It was "Simply Years Ahead". Incredible to think the sets dates from as early as 1966.

Cheers,
Brian

Steve_P 24th Aug 2006 11:39 am

Re: Philips T-Vette
 
Line Hold on these has two internal controls. L2050 and L2051.

L2050 is for 625 line operation. L2051 for 405 (To me it looks like both!). L2050 is out of circuit on 625 Lines. Switch to 405, adjust L2051, go to 625, adjust L2050 to bring in 625.

Cheers,

Steve P

Stewart 24th Aug 2006 1:16 pm

Re: Philips T-Vette
 
PaulRK's comments about AF11x transistors reminds me....I'm sure this model needlessly uses one as an audio pre-amp? A strange choice if I'm correct!

Kat - I've got the original Philips manual if you need a scan!

Kat Manton 24th Aug 2006 4:55 pm

Re: Philips T-Vette
 
Hi,

Well, I sent an email with a link to this page in it; the reply confirms I got the right set.

I gather there's full service information coming with the set; but thanks for the offer, Stewart :)

Ah, more AF11x transistors... excellent :-D

Hopefully tomorrow I'll be posting a pic or two and an initial report. I suppose there's a chance it might be AOA in which case all I'll be able to do is use it ;)

Regards, Kat

ppppenguin 24th Aug 2006 5:22 pm

Re: Philips T-Vette
 
Quote:

Originally Posted by Kat Manton (Post 74815)
Ah, more AF11x transistors... excellent :-D

Haven't got the schematics to hand but it's quite likely that this set uses the AF118. This is nothing like the AF114-7 series as it's a video output transistor which can withstand relatively high voltages while still having good HF response. That was a difficult trick way back then. Probably liable to tin whiskers and not so easy to substitute.

Paul_RK 24th Aug 2006 6:10 pm

Re: Philips T-Vette
 
Quote:

Originally Posted by ppppenguin (Post 74819)
Haven't got the schematics to hand but it's quite likely that this set uses the AF118...

The circuit's in the '67-8 R+TVS. It must just have been sound that was lost in my set (about ten years ago now), as the two AF115s are sound IF stages and the AF117, as Stewart mentions, is the AF amplifier. There's no AF118 used.

Paul

Steve_P 24th Aug 2006 6:25 pm

Re: Philips T-Vette
 
There is a Transistor AF181, but I don't know if it gets the PROBLEM though. I think I'd have heard of it if it did. Does anyone know one way or't'other?

Cheers,

Steve P

Focus Diode 24th Aug 2006 8:56 pm

Re: Philips T-Vette
 
Thanks Steve P. I should've remembered the line osc. coils!
Cheers again!
Brian

Kat Manton 27th Aug 2006 5:15 am

Re: Philips T-Vette
 
Hi,

It's arrived, it's a Philips T-Vette (not the Stella version) and it's very unwell.

But the poor little thing has competition and might have to wait a little while for attention... :-)

Regards, Kat

Steve_P 27th Aug 2006 7:38 am

Re: Philips T-Vette
 
Just tell me what appears to be wrong, I'll get the manual out and have a think.

Cheers,

Steve P

Kat Manton 25th Jan 2007 4:54 pm

Re: Philips T-Vette
 
1 Attachment(s)
Hi Steve,

Belated reply...
Quote:

Originally Posted by Steve_P (Post 75179)
Just tell me what appears to be wrong

Not a clue electrically, that's the least of its problems hence the "Wanted" post...

What I know so far:
  • Control escutcheon missing, hole in case front section.
  • One telescopic aerial broken but all the bits are there.
  • CRT replaced in 1980, reciept came with the set.
  • Solid-state EHT rectifier fitted in place of DY51.
Cheers, Kat

Steve_P 25th Jan 2007 5:57 pm

Re: Philips T-Vette
 
All the things listed are cosmetic, and somewhere in my garage (Ho Ho!) I've got a Philips T-Vette minus the tube. For why read above.

If you want to rob it for bits, I'll put your name on it. In the meantime, power it as above and see what is what. These aren't paticularly tricky to sort out. The solid state DY51 was common, as these are a bit tricky to get hold of. (I've got one somewhere!)

Hope this helps.

Steve P

P.S. Tube Volts- 11.0 V 66mA. Make sure the spark gap is clean!

Heatercathodeshort 27th Jan 2007 10:06 am

Re: Philips T-Vette
 
Hello Kat,
This was Philips answer to the little Sony 9-306 and 9-90 together with others from Japan. In comparison it was a poor performer both from operation and reliability. I remember visiting Philips service dept at Croydon in the late 60's [The set dated from 66/67] and they had a mountain of them stacked on Dexion racks awaiting service. The rack must have been 50ft long and 8ft high!
The 405 performance is quite good but 625/UHF seemed to produce a milky result lacking any punch. They did vary and of course and there were always the good ones. I have two of them. One works very well and the other is about average. Very well made sets but a bit dated in design even for the mid 60's. Hope you get it sorted. Regards John.

DoctorWho 3rd Feb 2007 1:43 pm

Re: Philips T-Vette
 
Quote:

Originally Posted by Steve_P (Post 99364)
Tube Volts- 11.0 V 66mA. Make sure the spark gap is clean!

Just to clarify, do you mean the CRT heater is 11 volts Steve? If it's too high how do you suggest lowering the voltage, the use of a resistor, or another method?

Peter.

Steve_P 3rd Feb 2007 8:39 pm

Re: Philips T-Vette
 
Yes, CRT Heater is 11 Volts. Follow HeaterCathodeShort's advice here...

https://www.vintage-radio.net/forum/...ad.php?t=14556

Saves me writing it all out again!

Cheers,

Steve P

Kat Manton 3rd Feb 2007 9:52 pm

Re: Philips T-Vette
 
Hi Peter,
Quote:

Originally Posted by DoctorWho (Post 100800)
If it's too high how do you suggest lowering the voltage, the use of a resistor, or another method?

As I suspect you're more familiar with circuitry of older valved sets, I think a little clarification is in order. The "HT" rail on this set is an electronically regulated 11V DC which also powers the CRT heater.

So if the heater voltage is too high, the supply to the entire set is high, probably due to a fault in the power supply circuitry. Alternatively it could just be out of adjustment but my experience is that things don't usually drift much.

But, if this supply is significantly more than 11V, the most likely suspect is that transistor T1513 (AD149) has failed short-circuit. The set (and CRT heater) would then be run from whatever unregulated voltage is present after rectification and smoothing, probably around 13V or more. While the rest of the set is likely to survive over-voltage, the CRT heater is unlikely to fare so well.

Hope that makes sense,

Regards, Kat


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