Ferranti Type 31 receiver - UK Vintage Radio Repair and Restoration Discussion Forum

Techman · 21st May 2017, 12:18 am

A radio buddy of mine who I told about the last surplus equipment junk electronics sale bought this radio complete with horn speaker. I had looked at the radio before the sale but not looked inside it as the back was on. I had thought about bidding for it if there had been little interest, but when I saw my pal put his hand up, I decided not to bid, and luckily it was knocked down to him. There was a round of applause from everyone in the room when he bought it

I hadn't seen any more of it until last night when he said he was having a loft clear out and that there were some 'free gifts' to be collected if I wanted them - not including this radio, I hasten to add! So I popped over and had the chance to have a closer look at the radio that he'd bought. I have to say that it's not often you find one of these 1920s TRF sets in such original and totally complete condition. He hasn't attempted to apply any power to it and doesn't intend to. I had warned him at the time that these horn type speakers are often open circuit, and he tells me that he's metered this one and it is indeed open circuit - this wouldn't have been the original speaker for this set anyway.

I've only ever seen a more original and un-messed with one of these type of sets once before, and it was many years ago and again, belonged to another CB radio operator. This was a battery set in a much more upright case with a purpose made fitted cover and it was absolutely mint, unfortunately, a couple of the valves had o/c heaters when I did some tests on it at the time. I didn't do any checks or testing on this latest radio other than removing one of the valves for a closer look - I really don't think anyone's touched this set in many years.

It's my opinion that these type of very early sets in this untouched sort of condition are really almost museum pieces, and any electronic restoration, if done at all, needs great care and time taken as I've seen far too many of these sets ending up like a dogs dinner!

This particular model is quite attractive in that it has the 'house roof' type top, rather than the flat top that some others of this model had - the downside being that you can't stand a speaker or anything else on the top of the cabinet.

There's no current plan for the set other than him having it as a display item for the time being. I have a feeling that I may eventually get asked to do the work on this set, but as I said to him, it will involve a lot of time, which I don't seem to have much spare of these days.

Pictures of the set taken at his house:-

Techman · 21st May 2017, 12:21 am

Pictures of the speaker:-

Ed_Dinning · 22nd May 2017, 8:22 pm

Hi, It should be an easily repairable set, windings could be one of the main problem areas. It has a fairly simple circuit.

As it is a mains set you will need to check the mains transformer for leakage very carefully.

Ed

Herald1360 · 22nd May 2017, 9:00 pm

Searching for Ferranti 31 schema turned up a circuit for the Ferranti 32 which looks like it could be very similar electrically though the physical layout is different.

Techman · 23rd May 2017, 1:12 am

Thanks chaps.

I did warn him at the time he bought it that open circuits on inter stage transformers were a common problem on these old sets, so we'll have to see if he's been lucky or not.

Paul_RK · 23rd May 2017, 1:16 pm

Doesn't seem likely that the radio will have been partnered by the 'speaker since new, as the radio dates from 1931-2 - Ferranti's first model, or at least the earliest one they saw fit to acknowledge in their 1956 valve and TV tube pocket book - and the horn is unlikely to be from much later than 1925, when they fell precipitately from favour. Plenty of good moving-coil units around by 1931 that would have enabled the set to give a much better account of itself.

A wonderful relic, though, and I fully agree it would be a great shame to sacrifice its internal condition for the sake of getting it going. I've a similarly untouched - beyond missing a couple of unobtainable valves - 1929 Columbia radiogram which won't be restored while it's in my custody unless I decide I've an unlimited number of hours to devote to doing it properly.

Paul

Gridiron · 23rd May 2017, 1:32 pm

The horn is a ATM Claritone from around 1925, as has been said, anyone who could afford the radio in 1931 would have most probably bought a later better speaker, Ferranti made moving coil ones at the time.
Mike.

21st May 2017, 12:18 am	#1
Techman Dekatron Join Date: Nov 2009 Location: Lincolnshire, UK. Posts: 5,000	Ferranti Type 31 receiver A radio buddy of mine who I told about the last surplus equipment junk electronics sale bought this radio complete with horn speaker. I had looked at the radio before the sale but not looked inside it as the back was on. I had thought about bidding for it if there had been little interest, but when I saw my pal put his hand up, I decided not to bid, and luckily it was knocked down to him. There was a round of applause from everyone in the room when he bought it I hadn't seen any more of it until last night when he said he was having a loft clear out and that there were some 'free gifts' to be collected if I wanted them - not including this radio, I hasten to add! So I popped over and had the chance to have a closer look at the radio that he'd bought. I have to say that it's not often you find one of these 1920s TRF sets in such original and totally complete condition. He hasn't attempted to apply any power to it and doesn't intend to. I had warned him at the time that these horn type speakers are often open circuit, and he tells me that he's metered this one and it is indeed open circuit - this wouldn't have been the original speaker for this set anyway. I've only ever seen a more original and un-messed with one of these type of sets once before, and it was many years ago and again, belonged to another CB radio operator. This was a battery set in a much more upright case with a purpose made fitted cover and it was absolutely mint, unfortunately, a couple of the valves had o/c heaters when I did some tests on it at the time. I didn't do any checks or testing on this latest radio other than removing one of the valves for a closer look - I really don't think anyone's touched this set in many years. It's my opinion that these type of very early sets in this untouched sort of condition are really almost museum pieces, and any electronic restoration, if done at all, needs great care and time taken as I've seen far too many of these sets ending up like a dogs dinner! This particular model is quite attractive in that it has the 'house roof' type top, rather than the flat top that some others of this model had - the downside being that you can't stand a speaker or anything else on the top of the cabinet. There's no current plan for the set other than him having it as a display item for the time being. I have a feeling that I may eventually get asked to do the work on this set, but as I said to him, it will involve a lot of time, which I don't seem to have much spare of these days. Pictures of the set taken at his house:- Attached Thumbnails

21st May 2017, 12:21 am	#2
Techman Dekatron Join Date: Nov 2009 Location: Lincolnshire, UK. Posts: 5,000	Re: Ferranti Type 31 receiver Pictures of the speaker:- Attached Thumbnails

22nd May 2017, 8:22 pm	#3
Ed_Dinning Dekatron Join Date: Jan 2004 Location: Newcastle upon Tyne, Tyne & Wear, UK. Posts: 8,194	Re: Ferranti Type 31 receiver Hi, It should be an easily repairable set, windings could be one of the main problem areas. It has a fairly simple circuit. As it is a mains set you will need to check the mains transformer for leakage very carefully. Ed

22nd May 2017, 9:00 pm	#4
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,535	Re: Ferranti Type 31 receiver Searching for Ferranti 31 schema turned up a circuit for the Ferranti 32 which looks like it could be very similar electrically though the physical layout is different. Attached Thumbnails __________________ ....__________ ....\|____\|\|__\|__\_____ .=.\| _---\__\|__\|_---_\|. .........O..Chris....O

23rd May 2017, 1:12 am	#5
Techman Dekatron Join Date: Nov 2009 Location: Lincolnshire, UK. Posts: 5,000	Re: Ferranti Type 31 receiver Thanks chaps. I did warn him at the time he bought it that open circuits on inter stage transformers were a common problem on these old sets, so we'll have to see if he's been lucky or not.

23rd May 2017, 1:16 pm	#6
Paul_RK Dekatron Join Date: Nov 2003 Location: Fakenham, Norfolk, UK. Posts: 4,256	Re: Ferranti Type 31 receiver Doesn't seem likely that the radio will have been partnered by the 'speaker since new, as the radio dates from 1931-2 - Ferranti's first model, or at least the earliest one they saw fit to acknowledge in their 1956 valve and TV tube pocket book - and the horn is unlikely to be from much later than 1925, when they fell precipitately from favour. Plenty of good moving-coil units around by 1931 that would have enabled the set to give a much better account of itself. A wonderful relic, though, and I fully agree it would be a great shame to sacrifice its internal condition for the sake of getting it going. I've a similarly untouched - beyond missing a couple of unobtainable valves - 1929 Columbia radiogram which won't be restored while it's in my custody unless I decide I've an unlimited number of hours to devote to doing it properly. Paul

23rd May 2017, 1:32 pm	#7
Gridiron Heptode Join Date: Apr 2010 Location: West Midlands, UK. Posts: 662	Re: Ferranti Type 31 receiver The horn is a ATM Claritone from around 1925, as has been said, anyone who could afford the radio in 1931 would have most probably bought a later better speaker, Ferranti made moving coil ones at the time. Mike.