What is this? looks RAF? - UK Vintage Radio Repair and Restoration Discussion Forum

HamishBoxer · 2nd Jan 2019, 7:24 pm

Had it years but no idea where it came from or what it is.

ex seismic · 2nd Jan 2019, 7:38 pm

VR65 is indeed RAF nomenclature.

turretslug · 2nd Jan 2019, 8:26 pm

Interesting, I like a bit of mystery chassis but it won't stop me being wildly wrong sometimes.

The style of construction and mains transformer, rectifier, choke and smoothing capacitor (all supposition) at top right suggest a base-station unit, maybe rack use. Demodulator valve under the big bottom left can? Perhaps a pre-adjusted single-frequency monitor receiver feeding line distribution, or a variable capacitor under the chassis making it tuneable across, say, the LF beacon band?

M0FYA Andy · 2nd Jan 2019, 8:37 pm

Whilst VR65 is indeed AM/RAF nomenclature, the ZC numbers on the IF transformers(?) are Army numbers.

A picture underneath would be useful, please.

Andy

G6Tanuki · 2nd Jan 2019, 9:08 pm

It does look more ground-station than airborne. I'm guessing that it's some sort of receiver or IF-strip.

I'd think the can on the left is the front-end: the rusty protruding spindle with the screw-thread - could it be the spindle of a capacitor?

I'd say the valve on the right with the brown Paxolin top-cap I'd guess is the detector or 1st-audio?

VR65 is the same as SP61 which was a 6-volt variant of the 4-volt-heater SP41 originally designed in the late-1930s as a RF-amp for Band-I TRF TVs - it was used in a lot of WWII gear in roles similar to the EF50, and I gather it proved to be rather more-reliable in service than its better-known metal-cased companion.

HamishBoxer · 2nd Jan 2019, 9:21 pm

Thank you all so far,I will get a picture of under chassis Thursday.

PS It is cold and dark out there tonight!

Heatercathodeshort · 2nd Jan 2019, 9:23 pm

It is possible that in it's present form it may have been modified for use as a sound channel in a home constructed television receiver.

VR [valve receiving] 65. As HE has mentioned, Mazda SP61. J.

turretslug · 2nd Jan 2019, 9:23 pm

Yes- perhaps that can could be the front-end of a relatively "local" performance receiver, there were things like SBA at ISTR around 30-40MHz or so. Were there such things as Gee monitor/check ground sets?

M0FYA Andy · 2nd Jan 2019, 10:26 pm

Is that a part number on top of the 'mains' transformer? The picture is too low-resolution and fuzzy to make it out, blowing it up doesn't help.

Andy

David Simpson · 3rd Jan 2019, 12:12 am

Well David, its nothing I recognise from my RAF Air Wireless/Air Comms days(1960's/70's). More than likely something from a ground installation. The valves are not secured enough for aircraft use, for a start.

Regards, David

ex seismic · 3rd Jan 2019, 9:35 am

The varnished screw heads is an Army thing. The WS38 uses the same style of IF can, I've just checked mine but it has no numbers on it.

Techman · 3rd Jan 2019, 1:49 pm

Quote:

Originally Posted by David Simpson

Well David, its nothing I recognise from my RAF Air Wireless/Air Comms days(1960's/70's). More than likely something from a ground installation. The valves are not secured enough for aircraft use, for a start.

Regards, David

Would those valves possibly be marked as for ground use only?

I certainly have some Air Ministry VR and VT valves that are actually labeled on the glass "for ground use only".

HamishBoxer · 3rd Jan 2019, 4:13 pm

Enclosed photo,s.

M0FYA Andy · 3rd Jan 2019, 4:54 pm

Again, an Army reference number on the transformer.

Andy

G6Tanuki · 3rd Jan 2019, 7:33 pm

Interesting that it's got a Belling-Lee coax socket in one place and a couple of Pye coax-connectors elsewhere - this hints that it's been 'got-at' post-WWII.

I'm still wondering what's under the big can with the rusty screwdriver-slotted bit sticking out the side.

HamishBoxer · 3rd Jan 2019, 9:20 pm

Mains transformer?

M0FYA Andy · 3rd Jan 2019, 10:36 pm

Quote:

Originally Posted by G6Tanuki

I'm still wondering what's under the big can with the rusty screwdriver-slotted bit sticking out the side.

I think there is a valve inside there, its holder is visible on the under-chassis view, along with an IF transformer or similar.

Andy

Refugee · 3rd Jan 2019, 11:19 pm

That can is marked "V6 VR65" so at least we know what valve is supposed to be in it.

turretslug · 3rd Jan 2019, 11:36 pm

Maybe a test jig, with a fixed frequency amplifier strip into some measurement/indicator device? Even if that bit seems to be essentially complete, quite a bit else is missing!

ms660 · 4th Jan 2019, 1:00 am

https://www.americanradiohistory.com...on-1951-10.pdf

https://vk2bv.org/archive/museum/rdf1.htm

https://vk2bv.org/archive/museum/k-files/rdf1.gif

Any use....?

Lawrence.

2nd Jan 2019, 7:24 pm	#1
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,935	What is this? looks RAF? Had it years but no idea where it came from or what it is. Attached Thumbnails __________________ G8JET BVWS Archivist and Member V.M.A.R.S

2nd Jan 2019, 7:38 pm	#2
ex seismic Heptode Join Date: Sep 2009 Location: Tonbridge, Kent, UK. Posts: 686	Re: What is this? looks RAF? VR65 is indeed RAF nomenclature.

2nd Jan 2019, 8:26 pm	#3
turretslug Dekatron Join Date: Nov 2011 Location: Surrey, UK. Posts: 4,397	Re: What is this? looks RAF? Interesting, I like a bit of mystery chassis but it won't stop me being wildly wrong sometimes. The style of construction and mains transformer, rectifier, choke and smoothing capacitor (all supposition) at top right suggest a base-station unit, maybe rack use. Demodulator valve under the big bottom left can? Perhaps a pre-adjusted single-frequency monitor receiver feeding line distribution, or a variable capacitor under the chassis making it tuneable across, say, the LF beacon band?

2nd Jan 2019, 8:37 pm	#4
M0FYA Andy Nonode Join Date: May 2007 Location: Preston, Lancashire, UK. Posts: 2,511	Re: What is this? looks RAF? Whilst VR65 is indeed AM/RAF nomenclature, the ZC numbers on the IF transformers(?) are Army numbers. A picture underneath would be useful, please. Andy

2nd Jan 2019, 9:08 pm	#5
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 14,005	Re: What is this? looks RAF? It does look more ground-station than airborne. I'm guessing that it's some sort of receiver or IF-strip. I'd think the can on the left is the front-end: the rusty protruding spindle with the screw-thread - could it be the spindle of a capacitor? I'd say the valve on the right with the brown Paxolin top-cap I'd guess is the detector or 1st-audio? VR65 is the same as SP61 which was a 6-volt variant of the 4-volt-heater SP41 originally designed in the late-1930s as a RF-amp for Band-I TRF TVs - it was used in a lot of WWII gear in roles similar to the EF50, and I gather it proved to be rather more-reliable in service than its better-known metal-cased companion.

2nd Jan 2019, 9:21 pm	#6
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,935	Re: What is this? looks RAF? Thank you all so far,I will get a picture of under chassis Thursday. PS It is cold and dark out there tonight! __________________ G8JET BVWS Archivist and Member V.M.A.R.S

2nd Jan 2019, 9:23 pm	#7
Heatercathodeshort Dekatron Join Date: Jun 2005 Location: Warnham, West Sussex. 10 miles south of DORKING. Posts: 9,147	Re: What is this? looks RAF? It is possible that in it's present form it may have been modified for use as a sound channel in a home constructed television receiver. VR [valve receiving] 65. As HE has mentioned, Mazda SP61. J.

2nd Jan 2019, 9:23 pm	#8
turretslug Dekatron Join Date: Nov 2011 Location: Surrey, UK. Posts: 4,397	Re: What is this? looks RAF? Yes- perhaps that can could be the front-end of a relatively "local" performance receiver, there were things like SBA at ISTR around 30-40MHz or so. Were there such things as Gee monitor/check ground sets?

2nd Jan 2019, 10:26 pm	#9
M0FYA Andy Nonode Join Date: May 2007 Location: Preston, Lancashire, UK. Posts: 2,511	Re: What is this? looks RAF? Is that a part number on top of the 'mains' transformer? The picture is too low-resolution and fuzzy to make it out, blowing it up doesn't help. Andy

3rd Jan 2019, 12:12 am	#10
David Simpson Nonode Join Date: Mar 2008 Location: Aberdeen, UK. Posts: 2,857	Re: What is this? looks RAF? Well David, its nothing I recognise from my RAF Air Wireless/Air Comms days(1960's/70's). More than likely something from a ground installation. The valves are not secured enough for aircraft use, for a start. Regards, David

3rd Jan 2019, 9:35 am	#11
ex seismic Heptode Join Date: Sep 2009 Location: Tonbridge, Kent, UK. Posts: 686	Re: What is this? looks RAF? The varnished screw heads is an Army thing. The WS38 uses the same style of IF can, I've just checked mine but it has no numbers on it.

3rd Jan 2019, 4:13 pm	#13
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,935	Re: What is this? looks RAF? Enclosed photo,s. Attached Thumbnails __________________ G8JET BVWS Archivist and Member V.M.A.R.S

3rd Jan 2019, 4:54 pm	#14
M0FYA Andy Nonode Join Date: May 2007 Location: Preston, Lancashire, UK. Posts: 2,511	Re: What is this? looks RAF? Again, an Army reference number on the transformer. Andy

3rd Jan 2019, 7:33 pm	#15
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 14,005	Re: What is this? looks RAF? Interesting that it's got a Belling-Lee coax socket in one place and a couple of Pye coax-connectors elsewhere - this hints that it's been 'got-at' post-WWII. I'm still wondering what's under the big can with the rusty screwdriver-slotted bit sticking out the side.

3rd Jan 2019, 9:20 pm	#16
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,935	Re: What is this? looks RAF? Mains transformer? __________________ G8JET BVWS Archivist and Member V.M.A.R.S

3rd Jan 2019, 11:19 pm	#18
Refugee Dekatron Join Date: Apr 2012 Location: Worksop, Nottinghamshire, UK. Posts: 5,554	Re: What is this? looks RAF? That can is marked "V6 VR65" so at least we know what valve is supposed to be in it.

3rd Jan 2019, 11:36 pm	#19
turretslug Dekatron Join Date: Nov 2011 Location: Surrey, UK. Posts: 4,397	Re: What is this? looks RAF? Maybe a test jig, with a fixed frequency amplifier strip into some measurement/indicator device? Even if that bit seems to be essentially complete, quite a bit else is missing!

4th Jan 2019, 1:00 am	#20
ms660 Dekatron Join Date: Apr 2011 Location: Cornwall, UK. Posts: 13,454	Re: What is this? looks RAF? https://www.americanradiohistory.com...on-1951-10.pdf https://vk2bv.org/archive/museum/rdf1.htm https://vk2bv.org/archive/museum/k-files/rdf1.gif Any use....? Lawrence.