Spy Radio? - UK Vintage Radio Repair and Restoration Discussion Forum

HamishBoxer · 31st Oct 2020, 9:43 pm

This I received recently and I am undecided whether or not it is WW2 spy radio or what.

The odd thing is the valves appear to have been sprayed to remove the type,not checked yet if 6 or 12volt .Possibly TCS Collins type.

The frequency (on the lid) is a bit odd 0.7---1.8 and 1.8---2.4Mhz.

Fitted with a 2 pin mains plug. Pictures to follow.

Despite a L and H switch (low/high?) there is an on/off plus another pull switch.

A Halloween mystery!

trh01uk · 31st Oct 2020, 11:52 pm

Is there an antenna connection?

Richard

Radio Wrangler · 1st Nov 2020, 3:06 am

I wonder...

Running over many years there has been a thing going in G-QRP circles of making spy-style transmitters and sometimes transceivers. I've seen almost perfect replica B2s, things built into fag packets and all points in-between.

Aspects of that look a bit too clean, a bit too recent for the era of those parts... bright solder joints, PVC sleeving. It would be mischievous to flog one on a rally junk stall, but maybe it got on the loose via an SK sale?

Methinks you might find the circuit in Sprat.

David

Terry_VK5TM · 1st Nov 2020, 4:16 am

I had a look through the Sprat index and several issues of Sprat based on what was in the index and nothing obvious stood out.

Hard to tell from the photo if the valves are glass or metal, if glass may be 6v6's?

trh01uk · 1st Nov 2020, 10:39 am

I note that WftW Volume 4 now has a further 300 (!!) chapters which are available for free download from Louis Meulstee's website. Its possible that this set is a little known spy set which has been captured in one of those chapters - but I'm afraid I don't have a spare day to sit there and go through all of them!

And if David is right about it being a reconstruction - that only begs the question "reconstruction of what?"

Richard

G4XWDJim · 1st Nov 2020, 10:57 am

David,
Would you include some more pics please from other well illuminated angles.

Jim

Silicon · 1st Nov 2020, 1:11 pm

Can you read the markings on the transformer?

The valves could be series filament types i.e. 0.1 or 0.2 Amp.

HamishBoxer · 1st Nov 2020, 1:33 pm

David ,(RW) it came from a collector who had a lot of German stuff I understand,I think I can say safely I bought it on Ebay and nobody or the seller did not have a clue as to what it might be.
The odd thing is there are a lot of old waxy and mica caps in parallel.Plus reses in series.
Yes,there is an aerial socket and earth.
No,the valves are not 6V6 etc as too small I think.Though why no markings on them with possibility of being re sprayed.

Yes,I will get the transformer markings .Here we are 120V and 12.6 V.

More photos to follow,I had a right job last night both with poor light and trying to load the pictures,normally no problem.

This gets more interesting ,there does not seem to be any coils!

BR815 is the code on the electrolytic caps.All smells very old and waxy.

Julesomega · 1st Nov 2020, 2:01 pm

I'm not seeing any RF components in there..?

Station X · 1st Nov 2020, 2:16 pm

I thought that too. Are there any variable capacitors?

HamishBoxer · 1st Nov 2020, 2:59 pm

Just realised, no tuning cap as well as no coils. So, I could be wrong re A and E socket.

Station X · 1st Nov 2020, 3:23 pm

Looks like a bit of reverse engineering is called for. The construction has a symetrical appearance. Multivibrator perhaps?

Radio Wrangler · 1st Nov 2020, 3:35 pm

Agreed!

No RF components and maybe what look like crystal sockets on the panel may be simple connectors for cables.

So that's the spy radio idea out the window. It was fun while it lasted.

David

HamishBoxer · 1st Nov 2020, 6:01 pm

Still wonder why the frequency was written on the lid and also a number 6, as if one of 6?

All very odd I admit.

G4XWDJim · 1st Nov 2020, 6:02 pm

The sockets on the panel have unequal size pins which are fairly common connectors. The valves are 6SK7, 6J5 or similar size not output valves of the 6V6 size.

Maybe it’s a pre-amp.

Jim

Cobaltblue · 1st Nov 2020, 6:16 pm

AF Sig Gen Maybe ?

Interesting Who Dunnit

Cheers

Mike T

HamishBoxer · 1st Nov 2020, 6:25 pm

Also a 2 pin mains plug with very tarnished pins,so certainly not been plugged in for many years.

newlite4 · 1st Nov 2020, 7:13 pm

I think that this could be medical. The RF frequencies that are marked on the lid may well be selectable carrier frequencies for a Phrenic Nerve Stimulator, the receiving coil would be just under the skin, the modulation frequencies being in the low audio range. Alternatively this may be an early TENS treatment unit.
Neil

HamishBoxer · 1st Nov 2020, 8:19 pm

Good thinking Neil. Still the mystery of why no valve markings though?

Station X · 1st Nov 2020, 8:43 pm

The markings just wear off. I've got several like that. It's not easy to identify an unknown valve in a metal envelope! In your case the components connected to it should help.

31st Oct 2020, 9:43 pm	#1
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,932	Spy Radio? This I received recently and I am undecided whether or not it is WW2 spy radio or what. The odd thing is the valves appear to have been sprayed to remove the type,not checked yet if 6 or 12volt .Possibly TCS Collins type. The frequency (on the lid) is a bit odd 0.7---1.8 and 1.8---2.4Mhz. Fitted with a 2 pin mains plug. Pictures to follow. Despite a L and H switch (low/high?) there is an on/off plus another pull switch. A Halloween mystery! Attached Thumbnails __________________ G8JET BVWS Archivist and Member V.M.A.R.S Last edited by HamishBoxer; 31st Oct 2020 at 9:54 pm.

31st Oct 2020, 11:52 pm	#2
trh01uk Octode Join Date: Nov 2010 Location: Ross-on-Wye, Herefordshire, UK. Posts: 1,652	Re: Spy Radio? Is there an antenna connection? Richard

1st Nov 2020, 3:06 am	#3
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,867	Re: Spy Radio? I wonder... Running over many years there has been a thing going in G-QRP circles of making spy-style transmitters and sometimes transceivers. I've seen almost perfect replica B2s, things built into fag packets and all points in-between. Aspects of that look a bit too clean, a bit too recent for the era of those parts... bright solder joints, PVC sleeving. It would be mischievous to flog one on a rally junk stall, but maybe it got on the loose via an SK sale? Methinks you might find the circuit in Sprat. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

1st Nov 2020, 4:16 am	#4
Terry_VK5TM Nonode Join Date: Oct 2010 Location: Tintinara, South Australia, Australia Posts: 2,339	Re: Spy Radio? I had a look through the Sprat index and several issues of Sprat based on what was in the index and nothing obvious stood out. Hard to tell from the photo if the valves are glass or metal, if glass may be 6v6's? __________________ Terry VK5TM https://www.vk5tm.com/

1st Nov 2020, 10:39 am	#5
trh01uk Octode Join Date: Nov 2010 Location: Ross-on-Wye, Herefordshire, UK. Posts: 1,652	Re: Spy Radio? I note that WftW Volume 4 now has a further 300 (!!) chapters which are available for free download from Louis Meulstee's website. Its possible that this set is a little known spy set which has been captured in one of those chapters - but I'm afraid I don't have a spare day to sit there and go through all of them! And if David is right about it being a reconstruction - that only begs the question "reconstruction of what?" Richard

1st Nov 2020, 10:57 am	#6
G4XWDJim Octode Join Date: Oct 2008 Location: Littlehampton, West Sussex, UK. Posts: 1,465	Re: Spy Radio? David, Would you include some more pics please from other well illuminated angles. Jim

1st Nov 2020, 1:11 pm	#7
Silicon Nonode Join Date: Jun 2007 Location: Coulsdon, London, UK. Posts: 2,163	Re: Spy Radio? Can you read the markings on the transformer? The valves could be series filament types i.e. 0.1 or 0.2 Amp.

1st Nov 2020, 1:33 pm	#8
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,932	Re: Spy Radio? David ,(RW) it came from a collector who had a lot of German stuff I understand,I think I can say safely I bought it on Ebay and nobody or the seller did not have a clue as to what it might be. The odd thing is there are a lot of old waxy and mica caps in parallel.Plus reses in series. Yes,there is an aerial socket and earth. No,the valves are not 6V6 etc as too small I think.Though why no markings on them with possibility of being re sprayed. Yes,I will get the transformer markings .Here we are 120V and 12.6 V. More photos to follow,I had a right job last night both with poor light and trying to load the pictures,normally no problem. This gets more interesting ,there does not seem to be any coils! BR815 is the code on the electrolytic caps.All smells very old and waxy. __________________ G8JET BVWS Archivist and Member V.M.A.R.S Last edited by HamishBoxer; 1st Nov 2020 at 1:46 pm.

1st Nov 2020, 2:01 pm	#9
Julesomega Nonode Join Date: Dec 2012 Location: Stockport, Greater Manchester, UK. Posts: 2,102	Re: Spy Radio? I'm not seeing any RF components in there..? __________________ - Julian It's good here

1st Nov 2020, 2:16 pm	#10
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,288	Re: Spy Radio? I thought that too. Are there any variable capacitors? __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

1st Nov 2020, 2:59 pm	#11
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,932	Re: Spy Radio? Just realised, no tuning cap as well as no coils. So, I could be wrong re A and E socket. Attached Thumbnails __________________ G8JET BVWS Archivist and Member V.M.A.R.S Last edited by HamishBoxer; 1st Nov 2020 at 3:06 pm.

1st Nov 2020, 3:23 pm	#12
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,288	Re: Spy Radio? Looks like a bit of reverse engineering is called for. The construction has a symetrical appearance. Multivibrator perhaps? __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

1st Nov 2020, 3:35 pm	#13
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,867	Re: Spy Radio? Agreed! No RF components and maybe what look like crystal sockets on the panel may be simple connectors for cables. So that's the spy radio idea out the window. It was fun while it lasted. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

1st Nov 2020, 6:01 pm	#14
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,932	Re: Spy Radio? Still wonder why the frequency was written on the lid and also a number 6, as if one of 6? All very odd I admit. __________________ G8JET BVWS Archivist and Member V.M.A.R.S

1st Nov 2020, 6:02 pm	#15
G4XWDJim Octode Join Date: Oct 2008 Location: Littlehampton, West Sussex, UK. Posts: 1,465	Re: Spy Radio? The sockets on the panel have unequal size pins which are fairly common connectors. The valves are 6SK7, 6J5 or similar size not output valves of the 6V6 size. Maybe it’s a pre-amp. Jim

1st Nov 2020, 6:16 pm	#16
Cobaltblue Moderator Join Date: Dec 2010 Location: Exeter, Devon and Poole, Dorset UK. Posts: 6,864	Re: Spy Radio? AF Sig Gen Maybe ? Interesting Who Dunnit Cheers Mike T __________________ Invisible airwaves crackle with life or at least they used to Mike T BVWS member. www.cossor.co.uk

1st Nov 2020, 6:25 pm	#17
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,932	Re: Spy Radio? Also a 2 pin mains plug with very tarnished pins,so certainly not been plugged in for many years. __________________ G8JET BVWS Archivist and Member V.M.A.R.S

1st Nov 2020, 7:13 pm	#18
newlite4 Octode Join Date: Nov 2003 Location: Bath, Somerset, UK. Posts: 1,805	Re: Spy Radio? I think that this could be medical. The RF frequencies that are marked on the lid may well be selectable carrier frequencies for a Phrenic Nerve Stimulator, the receiving coil would be just under the skin, the modulation frequencies being in the low audio range. Alternatively this may be an early TENS treatment unit. Neil __________________ preserving the recent past, for the distant future.

1st Nov 2020, 8:19 pm	#19
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,932	Re: Spy Radio? Good thinking Neil. Still the mystery of why no valve markings though? __________________ G8JET BVWS Archivist and Member V.M.A.R.S

1st Nov 2020, 8:43 pm	#20
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,288	Re: Spy Radio? The markings just wear off. I've got several like that. It's not easy to identify an unknown valve in a metal envelope! In your case the components connected to it should help. __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.