2-tube, 1930's radio mystery - UK Vintage Radio Repair and Restoration Discussion Forum

FStephenMasek · 16th Dec 2014, 3:32 am

What do you think of this? Does anything look familiar? Any suggestions?

http://i269.photobucket.com/albums/j...adioclosed.jpg

Unknown British radio dials, red label reads CAMCO casework
http://i269.photobucket.com/albums/j...itishdial1.jpg

Unknown British radio back
http://i269.photobucket.com/albums/j...hradioback.jpg

Unknown British radio chassis - valves are PM1LF and PM22
http://i269.photobucket.com/albums/j...isasfound1.jpg

Unknown British radio close-up of transformer
http://i269.photobucket.com/albums/j...merasfound.jpg

I drew this today (The moving contact is a piece of copper riding onto a on a semi-circular metal piece behind the dial.):
url=http://s269.photobucket.com/user/FStephenMasek/media/UnknownBritishRadioschematic.jpg.html]http://i269.photobucket.com/albums/j...oschematic.jpg[/url]

FStephenMasek · 16th Dec 2014, 4:44 am

I do not know how to edit the post above, so have to do another.

I have modified the schematic:
http://i269.photobucket.com/albums/j...icvsrsion2.jpg

I found this article on a radio with some similarities: to this unit:
http://www.eddystoneusergroup.org.uk...Two%201931.pdf

Herald1360 · 16th Dec 2014, 1:29 pm

Various makers used that sort of oval panel presentation- GEC, Lotus, Graves etc. Nearest in appearance I could find is this Nicholls 3 valver in RM.

http://www.radiomuseum.org/r/nichols...valve_set.html

AC/HL · 16th Dec 2014, 9:24 pm

It looks to be home constructed, or from one of the many small local manufacturers that sprang up in the early days, many of which disappeared without trace once the boom was over. I'd guess Birmingham for obvious reasons, dating from the late 20's, early thirties when the Regional scheme was introduced.

Eddystone and Camco (and Mullard of course) supplied components and cabinets to the home constructor market. The moving contact may be a form of "Extensor" to enable the stations to be separated on the dial, difficult in those days with simple detector-amplifier radios. Is it open when one of the marked stations is tuned and closed for the other?

FStephenMasek · 17th Dec 2014, 2:34 am

AC/HL, yes, the fixed part of it is a semicircle behind the upper half of the dial

FStephenMasek · 30th Dec 2014, 9:46 pm

The little radio plays, but is only receiving one station ,KFI at 640AM, a 50,000 watt station with a high antenna which is the most powerful signal to reach our location. I have no idea how good the tubes/valves are, just that the filaments work. I replaced a 2 meg resistor which was multiples of that. I also repaired the tube socket for the output tube. Three of the four spring connections from the movable tube socket to the base of the assembly had broken, so I soldered them. Disconnecting the wire from the center tap of the coil to the metal semi-circle behind the dial causes it to stop receiving.

16th Dec 2014, 3:32 am	#1
FStephenMasek Pentode Join Date: Jul 2011 Location: Mission Viejo, California, USA Posts: 144	2-tube, 1930's radio mystery What do you think of this? Does anything look familiar? Any suggestions? http://i269.photobucket.com/albums/j...adioclosed.jpg Unknown British radio dials, red label reads CAMCO casework http://i269.photobucket.com/albums/j...itishdial1.jpg Unknown British radio back http://i269.photobucket.com/albums/j...hradioback.jpg Unknown British radio chassis - valves are PM1LF and PM22 http://i269.photobucket.com/albums/j...isasfound1.jpg Unknown British radio close-up of transformer http://i269.photobucket.com/albums/j...merasfound.jpg I drew this today (The moving contact is a piece of copper riding onto a on a semi-circular metal piece behind the dial.): url=http://s269.photobucket.com/user/FStephenMasek/media/UnknownBritishRadioschematic.jpg.html]http://i269.photobucket.com/albums/j...oschematic.jpg[/url]

16th Dec 2014, 4:44 am	#2
FStephenMasek Pentode Join Date: Jul 2011 Location: Mission Viejo, California, USA Posts: 144	Re: 2-tube, 1930's radio mystery I do not know how to edit the post above, so have to do another. I have modified the schematic: http://i269.photobucket.com/albums/j...icvsrsion2.jpg I found this article on a radio with some similarities: to this unit: http://www.eddystoneusergroup.org.uk...Two%201931.pdf

16th Dec 2014, 1:29 pm	#3
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,536	Re: 2-tube, 1930's radio mystery Various makers used that sort of oval panel presentation- GEC, Lotus, Graves etc. Nearest in appearance I could find is this Nicholls 3 valver in RM. http://www.radiomuseum.org/r/nichols...valve_set.html __________________ ....__________ ....\|____\|\|__\|__\_____ .=.\| _---\__\|__\|_---_\|. .........O..Chris....O

16th Dec 2014, 9:24 pm	#4
AC/HL Dekatron Join Date: Nov 2003 Location: Heckmondwike, West Yorkshire, UK. Posts: 9,642	Re: 2-tube, 1930's radio mystery It looks to be home constructed, or from one of the many small local manufacturers that sprang up in the early days, many of which disappeared without trace once the boom was over. I'd guess Birmingham for obvious reasons, dating from the late 20's, early thirties when the Regional scheme was introduced. Eddystone and Camco (and Mullard of course) supplied components and cabinets to the home constructor market. The moving contact may be a form of "Extensor" to enable the stations to be separated on the dial, difficult in those days with simple detector-amplifier radios. Is it open when one of the marked stations is tuned and closed for the other?

17th Dec 2014, 2:34 am	#5
FStephenMasek Pentode Join Date: Jul 2011 Location: Mission Viejo, California, USA Posts: 144	Re: 2-tube, 1930's radio mystery AC/HL, yes, the fixed part of it is a semicircle behind the upper half of the dial

30th Dec 2014, 9:46 pm	#6
FStephenMasek Pentode Join Date: Jul 2011 Location: Mission Viejo, California, USA Posts: 144	Re: 2-tube, 1930's radio mystery The little radio plays, but is only receiving one station ,KFI at 640AM, a 50,000 watt station with a high antenna which is the most powerful signal to reach our location. I have no idea how good the tubes/valves are, just that the filaments work. I replaced a 2 meg resistor which was multiples of that. I also repaired the tube socket for the output tube. Three of the four spring connections from the movable tube socket to the base of the assembly had broken, so I soldered them. Disconnecting the wire from the center tap of the coil to the metal semi-circle behind the dial causes it to stop receiving.