OK, we're making progress.

There were 3 different chassis used in the R31C-A models so we need to narrow it down some more.

Here is the list of all possible model numbers that match your TV, now you can see why it can be hard to identify models.

R31C-A/2-C
R31C-A/2-R
R31C-A/3-C
R31C-A/3-R
R31C-A/4-Y

If you have another look at the back of the Astor chassis, somewhere should be an extra number and maybe also a letter. These will be the rest of the model number. Otherwise, I'll need to see a picture of the chassis to see if I can work out if it is a Series 2, 3 or 4 type.

I'll send you the HMV P1 chassis diagram tomorrow.

I know you have the diagram already, but can you let me know what the full model number of the HMV Trent is please. It should be PU3-something. I'd like to know what case model it is.

Ok, but I am afraid of damaging tubes while opening it, but I will get the service data and ill analyse it tonight

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"I'd rather have a CRT than nothing" - me
"people just throw working CRTs out, it is NOT FUNNY!" -me

It is a PU3 V6 but it also has the PU4 service data for it, I have a schematic for it here, I'll post a pic to Brad now

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"I'd rather have a CRT than nothing" - me
"people just throw working CRTs out, it is NOT FUNNY!" -me

I tried sending you the circuits at the email address on your profile page but they are not being delivered.

You'll need to check that it is correct, otherwise, email me and I'll reply.

With your HMV Trent you don't need to take the back off to see the model number. There should be a little square hole marked model number on the back. If you shine a torch in there you should be able to read the model number.

PU3 and V6 are chassis types and your TV is either a PU3 or a V6, it won't be both.