Pye 4311 export TV - service manual wanted

[dazzlevision]

Hello,

Pye 4311 export TV - service manual wanted

Does anyone, particularly our overseas members, have a service manual for this set?

I have just acquired this model, which has been modified for UK 625 UHF use by removing the original four pushbutton valve VHF tuner and replacing it with a UHF transistor type. I need to find out what sort of VHF tuner was originally fitted, as I hope to restore it to its original condition. It also has provision for a side mounted rotary UHF tuner, as fitted in many Ekco UK sets.

Looks to have been made around 1964 and has a very "Ekco" look to it inside.

Many thanks,

Dazzlevision

[German Dalek]

Hi,
I have a big schematic library for australian TVs, incl. a lot of PYE and HMV stuff.
I check for the number this evening.

Best regards

The German Dalek

[dazzlevision]

Hello German Dalek,

Many thanks for looking and I hope you are successful!

Regards,

Dazzlevision

[AndrewM]

Sounds like it may have been a New Zealand market set. Most Australian models had rotary VHF tuners.

A few English Pye based sets were sold here but your model number does not match any of the local models, however, the chassis may have been used under a different model number locally.

Can you post a picture of the chassis? I may be able to match it up to one of our imported models.

[dazzlevision]

Hello Andrew M,

The chassis is very similar to the one in Glenz32's Pye set in this thread:
https://www.vintage-radio.net/forum/...ad.php?t=78143

However, it's not exactly the same, as the VHF tuner in my set only has four pushbuttons. The set also has provision for fitting a side of cabinet mounted rotary type UHF tuner. The basic chassis looks very similar to Geln's.

Pye also made an FCC standard version of this chassis, for North America (probably Canada), with different IF frequencies and 50/60Hz frame timebase switching.

Thank you for taking the time to post here.

Regards,

Dazzlevision

[AndrewM]

Thanks for the link, pictures make things much easier.

We didn't get to see any of the imported chassis sets by the early to mid 1960's.

The only 4 channel push button tuner used in Australia was on Bush-Simpson TV's. Tuner was a Bushmatic T91.

Hopefully one of the NZ members may be able to help.

Andrew

[Synchrodyne]

Originally Posted by dazzlevision

Pye also made an FCC standard version of this chassis, for North America (probably Canada), with different IF frequencies and 50/60Hz frame timebase switching.

Interesting that the field timebase of that version was switchable and not just set to 60 Hz. Possibly the same model was also intended for sale in those South American countries that had adopted the System N 625-line variant, such as Argentina and Uruguay. Field frequency would likely be the only parameter that needed switching between System N (625) and System M (525). System N used the same channel frequencies as in North America, the same FM sound parameters (+/-25 Hz deviation and 75 µs pre-emphasis) and I should guess the same receiver IFs (45.75 MHz vision, 41.25 MHz sound).

One may wonder though whether the UHF tuner in the American version followed North American or British/European practice, which seemed to be markedly different back in the valve and early solid-state days.

Cheers,

[dazzlevision]

Hello,

Here are some pictures of the TV. Note that the red lens "mains power on" indicator is a mod; it was originally a window for a light dependant resitor (auto contrast adjustment with room illumination). There was also a side mounted valve UHF tuner (Ekco rotary type).

The original VHF (four) push button tuner has been replaced by a transistorised UHF tuner unit (and the original valve rotary UHF tuner removed, I suspect).

The "UHF" push button operates a Bowden cable that switches the VHF tuner between VHF (reception) and UHF (extra common IF amp stage) operation.

The set has an Octal remote control socket at the rear and can operate on 110 or 230V mains supplies.

The valve line up is:

IF panel: EF183, EF184, PCF80, EF85, EF80 (or may be EF85 - valve marking indistinct), PCL84 (video output), PCL82 (x2 - push/pull audio output stage).

Timebase panel: ECC82 (x3), EH90 (noise cancelled sync separator), PL504, PY800.

The EHT rectifier is DY86/7.

CRT is a Mullard twin-panel type (A59-16W).

Regards,

Dazzlevision

[Tazman1966]

Look interesting Dave. I look forward to reading the ressurection of this highly unusual (well by UK standards!) television.

[German Dalek]

Yepp, I took a look at the australian PYE sets of my schematic library and
they have all different tube line-ups.
Australian built sets have the information PYE-Tecnico written on the back.
Last, australian PYE sets (and of course all others aussis) can be switched to
230 and 240V AC, but not to 110V AC!
So we are back in Europe?!.
My youngest spanish TV, early 60s, has the 110/220 Volts AC option, too.
I have 2 argentinian TVs, as I remember right they have no 110 Volt option.
But I have now more information on italian PYE sets, so please read soon
my thread about PYE around the world.

Best regards,

The german Dalek

[German Dalek]

Now I' m a little closer to the problem, the TV in question has a 110 Volt option,
the italian sets (please read my other posts) are made for 125 and 220 Volts
AC.
110/220 Volts sets are maybe made for another european country, eastern
communist country, South America, Asia or Africa.
I have a friend in Finland who owns a PYE tube portable which has a plastic
shield on it, where all knob functions are discribed in about 8 languages.
Yes including arabian letters.
So why not for these countries?
What I've found out is that the tube line-up of the italian PYE L 233 is very
close to the set in question.
It has EF 80, EF 85, EF 183, EF 184, EH 90, but unusual, the line output is
a PL 36! The other PYE sets of this time have the PL 36 (an older but longer
lasting tube than the PL 500) in operation, too!
Anyway, with the schematic of this set it will be easier to fix it.
But the country of dedication for this set is still a big question!

Best regards,

The german Dalek

[dazzlevision]

Hello,

I've been doing some more work on this TV and have established that it is a CCIR (only) standard set (38.9 MHz vision IF and 5.5MHz sound IF), after checking the internal components in the IF transformers/coils and comparing them with circuits for similar Pye and Ekco export sets of the mid 1960s.

However, I still need the exact circuit for the Pye 4311, in order to determine exactly what version of VHF four push button tuner was originally fitted (and its IF output matching/coupling components - usually a low value resistor - around 33 ohms and a small value capacitor - around 39pF).

I'm pretty sure the VHF tuner in the Pye 4311 was an export version of the Plessey four pushbutton tuner fitted to several Pye and Ekco UK 405/625 sets in the Pye 11U and Ekco T418 series (and in some pre-KB era Regentone and RGD sets).

In the Pye/Ekco export TV circuits that I do have, there are several variations in the detailed circuitry of this tuner and some versions have five pushbuttons, whereas the 4311's has only four holes in the front control panel.

In addition, some versions of the Plessey export tuner have a Bowden cable linkage (from a separate "UHF" pushbutton on the set's front control panel, not on the VHF tuner itself) to a UHF/VHF slider switch on the VHF tuner (like some of the Pye/Ekco UK TV11U/T418 series sets had), but others use one of the five tuner pushbuttons to mechanically set the mixer stage of the VHF tuner to the IF frequency range and avoid the Bowden cable switching arrangement.

I have now fitted a five pushbutton Plessey VHF tuner in place of the non-original Bush (Plessey made) UHF pushbutton tuner (with Bowden cable UHF/VHF changeover switching) and I am getting pictures but they are not very good (instability and smearing/"plastic" effects on the test card). I will examine the tuner for dry joints and clean the slider switch contacts, to see if that helps.

There is a more serious problem though, the LOPT exhibits the classic progressive overheating symptoms after it's been on for more than ten minutes or so. As it's an export LOPT (625 only), I doubt I'll be able to source an exact replacement (Pye/Ekco part number AN00002). I will try to remove the wax on the EHT overwinding, to see if that helps (as it has done for other sets mentioned in this fourm).

Oh, and the Mullard A59-16W twin panel picture tube is pretty poor too!

Still looking for a service manual/circuit for the Pye 4311.

Regards,

Dazzlevision

[Tazman1966]

Good progress so far sir for this potentially very rare set.

[dazzlevision]

Originally Posted by Tazman1966

Good progress so far sir for this potentially very rare set.

Hello Tas,

Yes, apart from the LOPT and the CRT!

However, I have replaced all the old TCC and Hunts paper dielectric capacitors, as they were all less than 1MOhm insulation (even the ones in hermetically sealed metal cans), as well as quite a few resistors that had gone very high. I've also cleaned up the surfaces of the two PCBs, chassis and wiring as I go along. It looks a lot more respectable now, apart from the outside!

Whoever fitted the Bush/Plessey transistor UHF tuner used some tin snips to cut away the unwanted part of the controls panel metalwork that the original VHF tuner was fitted to. So, I'll need to do some metal bashing myself to fit the correct Plessey four pushbutton VHF tuner.

The Bush/Plessey UHF tuner was screwed to the bottom of the cabinet with two long screws and several large cup washers used as spacers. The insulating small wooden square covering over the screw in leg captive threaded stud was removed to allow it, so if legs were fitted and metal, one could become live!

I've also removed the red mains on indicator and refitted the Mullard ORP12 LDR assembly, but the front lens/window is long gone.

There must be a service sheet or manual out there somewhere...........

Regards,

Daz

[Billy T]

Originally Posted by AndrewM

Sounds like it may have been a New Zealand market set. Most Australian models had rotary VHF tuners.

It bears no resemblance to any NZ chassis, and in particular, we did not have any PYE sets with multiple-tap dropper resistors, and all PYE models with PC boards had mains transformers. Push-button tuners were also conspicuously absent.

I'm not 100% sure, but I think that we had no multiple-tap dropper resistors period.

Cheers

Billy

[dazzlevision]

Hello,

Well, I now have a reasonably good picture on the set, albeit until the LOPT starts to get hot!

I have attached some pictures of the UK market Pye TV23UF 405/625 TV Plessey VHF four pushbutton tuner I have found in my stores and the export Plessey five pushbutton tuner removed from my Pam export TV.

Comparing the two, they seem virtually identical electrically (apart from the aerial input matching balun on the export tuner) and have the same external connections, UHF tuner IF input signal Belling-Lee coax socket and three pole UHF/VHF slider switch assembly (mounted on the small bracket with an IF can and coax socket on it).

I think it should be possible to swap over the pushbutton mechanisms between the two tuners, thereby providing me with a four pushbutton unit that will fit into the 4311 set. All I need to do then, is make up two mounting brackets to fix the tuner to the TV's metal control panel. It looks as if two flat (either square or triangular) plates either side of the tuner should do.

I may need to adjust the tuner's IF output coupling components (C & R) and realign its IF output coil and the input coil of the first IF stage on the main chassis.

Regards,

Dazzlevision

[Brigham]

Is there any significance to the tuner panel numbering, which seems to suggest that (in British terms) channel 1 isn't used, and that channel 5 is in Band III?

[dazzlevision]

Quite probably.

Looking through a listing of world TV channels, I cannot find one that uses only the channel numbers printed on my Pye 4311 TV's control panel escutcheon. The closest I can find (in a 1978 JVC technical guide to their VHS VCR system) is the Western European "E" channels: 2 to 4 (Band 1) and 5 to 12 (Band 3).

The 5 button VHF tuner I have (pictured in an earlier post here) came from another Pye group export TV, branded "Pam", which has 1 - 4 and 5 -12 printed on the control panel escutcheon.

Regards,

Dazzlevision

[hans]

We had channels 2-4 in band 1 and 5-12 in band 3. I think channel 12 wasn't defined in the beginning and came later. That might be the reason for the "5-11". This set is from the 50's?

[dazzlevision]

Hello Hans,

The Pye 4311 was made around 1964-5.

Regards,

Dazzlevision