Murphy A28C Service Data Wanted. - UK Vintage Radio Repair and Restoration Discussion Forum

DoctorWho · 12th Oct 2007, 4:36 pm

Can anyone help me with service data for a Murphy A28C console radio please? I haven't yet taken the chassis out, but I suspect it probably has a condenser block, which I will need datails of.

If anyone can help with data for this set I would be extremely grateful. Does the data for the A26C compare anything like the data for the A28C?

Thanks in advance for any help.

Peter.

Patrick Dixon · 12th Oct 2007, 4:45 pm

The schematic is here:- http://www.******************************/A28C.jpg

DoctorWho · 12th Oct 2007, 8:44 pm

Thanks Patrick, that's extremely helpful.

Has anyone got a component layout diagram and, most importantly, details of the condenser block, as I will need a diagram of the condenser block to be able to tackle the set.

Thanks again for the help,

Best regards,

Peter.

Paul Stenning · 13th Oct 2007, 6:54 pm

I now have data (from ERT) for the A28 which I assume is similar to the A28C. It has a basic layout diagram of the main and power chassis. The only info on the condenser blocks is which condenser numbers (circuit diagram references) are in them on the chassis layout diagrams.

Since the condenser blocks were intended to be replaceable components and not rebuilt, I doubt even the manufacturer's service manual would be very forthcoming with information.

Send me a PM with your email address and I'll send it to you FOC.

It will be on the next CD/DVD-ROM and by email in due course.

DoctorWho · 13th Oct 2007, 7:27 pm

Hello Paul,

That's very kind, thank you. Even knowing which condensers are in which block will be extremely helpful, at least I can then work out what goes where.

I've sent you a PM with my E-mail address. I shall also look forward to buying a copy of your next CD.

Thanks again Paul,

All the best,

Peter.

mickjjo · 13th Oct 2007, 10:46 pm

Hi Peter, There is an article by Mike Barker on Murphy condenser blocks in the BVWS Bulletin, Vol 20 No 6, December 1995, P104/5. I have attached an enlarged scan of the A28C condenser block diagram. This should be much clearer than the PDF version on the BVWS CD. Hope this helps

.

Regards, Mick.

DoctorWho · 14th Oct 2007, 2:28 pm

Hello Mick,

That is EXTREMELY helpful, many thanks for this!

There are 3 condenser blocks in this particular set, are the other two included by any chance?

Thanks again,

All the best,

Peter.

mickjjo · 14th Oct 2007, 2:40 pm

Hi Peter, There are 9 different condenser block diagrams in that article, apparently they are all stamped with a Murphy part No. beginning with "W", so if you can find the numbers I can check.

Regards, Mick.

.

DoctorWho · 14th Oct 2007, 3:18 pm

Thanks Mick, I have just sent you a PM about this.

Thanks again for the help,

All the best,

Peter.

Leon Crampin · 14th Oct 2007, 10:50 pm

Peter, It looks as though you should now have the information you need. If you look on the Murphy circuit diagram there are seemingly meaningless letters at certain points. For example, V1 cathode is denoted as "H". This is in fact the capacitor block terminal designation for C11 which is connected here. Note that there are two earth connections J & D which are detailed on the circuit.

Regards, Leon.

12th Oct 2007, 4:36 pm	#1
DoctorWho Rest in Peace Join Date: Apr 2005 Location: Devon Posts: 850	Murphy A28C Service Data Wanted. Can anyone help me with service data for a Murphy A28C console radio please? I haven't yet taken the chassis out, but I suspect it probably has a condenser block, which I will need datails of. If anyone can help with data for this set I would be extremely grateful. Does the data for the A26C compare anything like the data for the A28C? Thanks in advance for any help. Peter.

12th Oct 2007, 4:45 pm	#2
Patrick Dixon Hexode Join Date: Aug 2007 Location: Bristol, UK. Posts: 480	Re: Murphy A28C Service Data Wanted. The schematic is here:- http://www.******************************/A28C.jpg

12th Oct 2007, 8:44 pm	#3
DoctorWho Rest in Peace Join Date: Apr 2005 Location: Devon Posts: 850	Re: Murphy A28C Service Data Wanted. Thanks Patrick, that's extremely helpful. Has anyone got a component layout diagram and, most importantly, details of the condenser block, as I will need a diagram of the condenser block to be able to tackle the set. Thanks again for the help, Best regards, Peter.

13th Oct 2007, 6:54 pm	#4
Paul Stenning Administrator Join Date: Dec 2002 Location: Cardiff Posts: 9,071	Re: Murphy A28C Service Data Wanted. I now have data (from ERT) for the A28 which I assume is similar to the A28C. It has a basic layout diagram of the main and power chassis. The only info on the condenser blocks is which condenser numbers (circuit diagram references) are in them on the chassis layout diagrams. Since the condenser blocks were intended to be replaceable components and not rebuilt, I doubt even the manufacturer's service manual would be very forthcoming with information. Send me a PM with your email address and I'll send it to you FOC. It will be on the next CD/DVD-ROM and by email in due course. __________________ Paul Stenning Forum Admin/Owner and BVWS Webmaster

13th Oct 2007, 7:27 pm	#5
DoctorWho Rest in Peace Join Date: Apr 2005 Location: Devon Posts: 850	Re: Murphy A28C Service Data Wanted. Hello Paul, That's very kind, thank you. Even knowing which condensers are in which block will be extremely helpful, at least I can then work out what goes where. I've sent you a PM with my E-mail address. I shall also look forward to buying a copy of your next CD. Thanks again Paul, All the best, Peter.

13th Oct 2007, 10:46 pm	#6
mickjjo Rest in Peace Join Date: Jul 2004 Location: Dartford, Kent, UK. Posts: 1,661	Re: Murphy A28C Service Data Wanted. Hi Peter, There is an article by Mike Barker on Murphy condenser blocks in the BVWS Bulletin, Vol 20 No 6, December 1995, P104/5. I have attached an enlarged scan of the A28C condenser block diagram. This should be much clearer than the PDF version on the BVWS CD. Hope this helps . Regards, Mick. Attached Thumbnails

14th Oct 2007, 2:28 pm	#7
DoctorWho Rest in Peace Join Date: Apr 2005 Location: Devon Posts: 850	Re: Murphy A28C Service Data Wanted. Hello Mick, That is EXTREMELY helpful, many thanks for this! There are 3 condenser blocks in this particular set, are the other two included by any chance? Thanks again, All the best, Peter.

14th Oct 2007, 2:40 pm	#8
mickjjo Rest in Peace Join Date: Jul 2004 Location: Dartford, Kent, UK. Posts: 1,661	Re: Murphy A28C Service Data Wanted. Hi Peter, There are 9 different condenser block diagrams in that article, apparently they are all stamped with a Murphy part No. beginning with "W", so if you can find the numbers I can check. Regards, Mick. .

14th Oct 2007, 3:18 pm	#9
DoctorWho Rest in Peace Join Date: Apr 2005 Location: Devon Posts: 850	Re: Murphy A28C Service Data Wanted. Thanks Mick, I have just sent you a PM about this. Thanks again for the help, All the best, Peter.

14th Oct 2007, 10:50 pm	#10
Leon Crampin Octode Join Date: Nov 2005 Location: Surrey, UK. Posts: 1,870	Re: Murphy A28C Service Data Wanted. Peter, It looks as though you should now have the information you need. If you look on the Murphy circuit diagram there are seemingly meaningless letters at certain points. For example, V1 cathode is denoted as "H". This is in fact the capacitor block terminal designation for C11 which is connected here. Note that there are two earth connections J & D which are detailed on the circuit. Regards, Leon.