Pye PCR2

[Joe]

Right, that's all the waxies and electrolytics restuffed.

   

As for performance, MW isn't very good and LW is barely working. I can JUST hear the Home Service, though at 1250m, not 1515m, so maybe the alignment has been got at.

- Joe

[pwdrive]

Oh stuff....Like a lot of things it's a personal choice, sometimes I do and sometimes I don't, I suppose it can help to preserve the original capacitors manufacturers liason with the company that built the set thus helping to preserve any historical connection.

Lawrence.

[Skywave]

Right, that all the waxies and electrolytics restuffed.
As for performance, MW isn't very good and LW is barely working. I can JUST hear the Home Service, though at 1250m, not 1515m, so maybe the alignment has been got at.
- Joe

Possibly: perhaps the dial cursor is out of position. I wouldn't try to sort out any possible mis-alignment problems yet, though. [Aside: In sets of this age, I have known the mica caps. in the osc. cct. to be way off value]. However, I reckon that a general check of the values of all resistors is in order next. Don't forget to give the w/change switch a good squiring with switch cleaner. Then take voltage measurements: you may then find a tired valve or two. When all appears to be in order on all of those fronts, then I'd start thinking about investigating alignment, tracking, calibration, etc. - using appropriate test equipment, of course.

Al.

[Joe]

Yes, resistors, especially the big ones, are next on the list.

I've looked at the alignment instructions and can't make head or tail of it as it doesn't say what to twiddle in what order.

A couple of the cores look like they have been fiddled with before but adjusting these made no difference. I fully unscrews one and found that the cap has come adrift from the actual core.

The cursor is bang on on MW, by the way.

I'll take some voltage readings but they won't mean much to me - I'll post the results here. I'm not even sure which valve is which as three are the same type and I don't have a chassis lay-out diagram. That's a job for tomorrow when (hopefully) the light will be better.

- Joe

[Skywave]

Yes, resistors, especially the big ones, are next on the list.

Presumably, by the term 'big ones' you mean the ones that are 'big' in terms of Ohmic value, not 'big' as in physical size or wattage. It's high-Ohmic value resistors that are more prone to drifting high in value than lower value ones.

I've looked at the alignment instructions and can't make head or tail of it as it doesn't say what to twiddle in what order.

With a straight single-conversion superhet as you have there, the procedure is always first to check the alignment of the I.F. strip - for which a frequency-calibrated signal generator is needed as an absolute minimum item of test kit. Then proceed to the get the local oscillator running at the correct frequencies and getting the padding & tracking correct. Again, the appropriate test kit is essential to do this. The alignment of any L/C ccts. that are from the mixer grid to the aerial socket can come last of all.
[/quote]

A couple of the cores look like they have been fiddled with before but adjusting these made no difference. I fully unscrewed one and found that the cap has come adrift from the actual core.

In that case, I would suggest that you remove each I.F. can from the chassis and examine its internals. Trying to check the I.F. alignment if there are faults in the I.F. transformers will obviously be a waste of time.

The cursor is bang on on MW, by the way.

So presumably then you've checked the calibration and a few places on the dial. Did you use a sig. gen.?

Just trying to make constructive suggestions. Provided that you keep strictly to a logical method of working, keeping in mind the 'block diagram' of the set, which valve does what, and have some idea of what voltages look 'about correct' in certain places, you should make good progress. And when I say voltages 'look correct', what I have in mind are voltages that are obviously incorrect - such as 20v on an anode, 100v on a cathode and substantial positive voltage on a control grid.

Al.

[Joe]

Thanks, Al. I'll report back.

- Joe

[Joe]

I've had a look in one of the IFTs as the wire coming out of the top needed replacing anyway.

I don't think that there's any way that the cores are going to come out in one piece as they look just like lumps of rust.

I'll take some voltage measurements later in the hope that there's something else amiss but am not hopeful.

Alignment doesn't scare me as I've got an Advance E2 signal generator. I did my radiogram with it with no data at all.

Cheers

- Joe

[Joe]

Here we go. Measurements taken with digital meter while tuned to Radio Sheffield (290m):-

   

All pretty well Greek to me.

Don't anybody waste too much time a-pondering as I'm currently minded to list it for sale on The Dark Side; with Golborne coming up it may shift.

- Joe

[Skywave]

Joe - before you go any further with this, stop now! Having looked at the valve layout, under chassis view, that you've sent in, someone has been playing 'valve shuffling'!

If you look at the photo of the above chassis and the photos of the below chassis layouts, you can easily deduce what valves should be in the appropriate sockets.
The 6K8G is in the wrong socket. This socket is for the R.F. amplifier and should be an EF39. The EBC33 is in the wrong socket. This socket is for the mixer / oscillator and the 6K8G should be in there. The EF39, adjacent to the 6V6G is for the detector / AGC / 1st. AF amp.: the EBC33 should be in there.
So all in all, I'm very surprised that you were able to receive anything at all!

All that assumes that your 'Under-Chassis View' drawing is correct - and I assume that it indeed is - but just giving myself an 'escape route' for my declaration at the top of this post!

Al.

[Joe]

Interesting indeed, Al.

Actually I've just realised that the EBC33 and 6K8GT are reversed on the diagram. That still means that the former is in the wrong place but when I tried to put it in the base next to the 6V6 the top-cap lead wouldn't reach.

Only the 6K8GT has clear markings. The EF39s, or what I'm taking to be EF39s going by their size and shape, have lost most of there paint and hence the markings.

The EBC33 doesn't have anything on the bulb.

   

   

- Joe