I don’t intend making any of the material on Kevin Chants disc publicly available.

The schematic is such poor quality and virtually unreadable. I don’t think Kev would mind if viewed privately by experts who might be able to make some sense of it.

Photo uploaded to Post 44.

I just checked with Kev and its ok to show the 552 Series schematic here.

Eclipse 552 Circuit Diagram

Document uploaded to Post 48.

I see what you mean about unreadable.

I don't know what you need more to view that - a sense of imagination or a sense of humour!

Looks like a 'join the dots' puzzle!

Might give that a go.

Fred.

Yes Fred, I was thinking along the same lines.

The bonus is that the valve line-up and IF for this schematic is already known.

Please pass on my thanks to Kevin (and thanks MonochromeTV for chasing that up).

I am in the process of trying to enhance the image and trace anything obvious to see how close it appears to what the radio I have.

Much appreciation to all who have weighed in.

More ignorance to display here...

I have begun tracing the image of the circuit out (I will email Brad an image of the current state of play to put up here) but am a little confused about the valve symbology used.

Looking at the diagram (and squinting really hard ), the 1st valve (1C4) appears to have the screen and suppresor grids drawn as being internally connected - am I imagining this or in my ignorance (of which I have heaps), am I misinterpreting the valve diagram?

Why would the suppressor grid be at the same potential as the screen grid? Wouldn't that defeat the purpose of the suppressor grid? Or is the suppressor grid not drawn (or is it too feint) on the diagram and the screen grid drawn as 2 parts around the anode?

Eclipse 552 Circuit Diagram

Hi Jonk, the guy drawing the circuit may have been used to drawing tetrodes.
With no suppressor the screen grid just 'surrounds' the plate.
A pentode symbol may not have been in his mind yest,
Fred.

In some cases I can (and have) darkened lines to make things clearer before converting to PDF, though in this case there first has to be ink on the original. If there winds up being another source for this circuit, please send it and I will update it here.

Yes Fred is correct.

The screen grid surrounds the plate in this case. The suppressor grid, which is tied to one side of the filament, is not shown.

Document uploaded to Post 55.

Hi Brad, that enhancement helps.
I had a go tracing over the fainter original and got most of the circuit out except for the area around the vibrator.
I'll have another go on the enhancement.
This is not helping jonk that much bit I always like a challenge!
Fred.

Ok done!
I'll scan my effort and send to Brad.
I had to use my imagination in the power supply area.
I have not attempted to put in any values just tried to get the ciruit to a working model.
Fred.

Eclipse 552 Circuit Diagram