Mystery metrology question - UK Vintage Radio Repair and Restoration Discussion Forum

The Philpott · 10th Nov 2016, 6:32 pm

...What is it?

I am advised that (a) former owner was connected with the GPO and also with Tank warfare.

Gun laying? cable laying? Depth measurement? (Probably not the latter as it has no ad.patt. reference)

It is quite small and has an FSD demand of 1mA. When protected with 8.2kohm it gives an FSD of 9volts, and is likely to end up in use as a voltmeter or a petrol contents gauge

paulsherwin · 10th Nov 2016, 7:28 pm

It could be from a GPO reflectometer. Was GPO kit of that era marked with a broad arrow?

Herald1360 · 10th Nov 2016, 7:39 pm

AP..... suggests airforce.

Radar rangefinder readout?

The Philpott · 10th Nov 2016, 8:41 pm

Could be radar (but a ground based set as it has no backlighting?)

Time Domain Reflectometry a possibility.

The compactness, light weight and surface mount flange hint at portable equipment and simplicity of quick testing by substitution..

bluepilot · 10th Nov 2016, 8:44 pm

If you google model 909 meter you'll find all sorts of examples with various scales. This one appears to have been part of a range finder. Maybe it was used to find the range of your enemy so a tank could shoot at him?

AC/HL · 10th Nov 2016, 8:55 pm

I thought AP meant Admiralty Pattern, but Airforce and Army also fit! Either way it's possibly for test equipment of some description. 7000 yards is about 6.4km or 4 miles.

Station X · 10th Nov 2016, 8:58 pm

Quote:

Originally Posted by paulsherwin

It could be from a GPO reflectometer. Was GPO kit of that era marked with a broad arrow?

I can't remember any GPO equipment being marked with a broad arrow.

Nymrod121 · 10th Nov 2016, 8:59 pm

Might the reference be associated with an 'Air Publication' document?
Richard (trh01uk), perhaps you can advise ...
Best wishes
Guy

bluepilot · 10th Nov 2016, 9:24 pm

Quote:

Originally Posted by AC/HL

I thought AP meant Admiralty Pattern, but Airforce and Army also fit! Either way it's possibly for test equipment of some description. 7000 yards is about 6.4km or 4 miles.

Here's a model 909 for measuring up to 5v
http://picclick.co.uk/Vintage-Volts-...104615814.html
and here's one for 10 mA which also indicates it was manufactured by Ernest Turner
http://www.ebay.co.uk/itm/DC-Milli-A...p2047675.l2557

It still doesn't tell us what the above one was for but 4 miles sounds about the right range for a tank shooting at something. It's a bit short for a naval gun.

M0FYA Andy · 10th Nov 2016, 10:35 pm

I am totally confident that 'A.P.54959' on the dial means 'Admiralty Pattern 54959'.

'A.P' meaning 'Air Publication' is never seen as a reference on an item of hardware, but as the reference (with accompanying digits) on a document.

The Stores Reference for an Air Ministry or RAF meter would be typically 5Q/xxxx or 10A/xxxx

Andy

The Philpott · 10th Nov 2016, 11:44 pm

Andy I suspect you are correct. I was looking for AD PATT at the very least but as the meter is very small AP is understandable. Finding a reference to 54959 is proving a challenge though. There is a good reference to WW1 numbers but later ones, no such luck.

I am winging it a bit, but Gunlaying wise this might correspond to the range of the guns on a small vessel- eg corvette.

Oldelectronics · 11th Nov 2016, 12:04 am

Don't think its off a tank early on it was normally done with mk1 eyeball most early tanks had a limited maximum range against another tank on a Sherman for example about 800 metres. Then on more modern tanks like Chieftain they then used a ranging gun and today laser and ranges increased (starting with Centourian and its 105mm gun) after Centourian and onto Chieftain ranges were measured in metres (Certainly at the start of the 70s) not much help sorry!

The Philpott · 11th Nov 2016, 12:38 am

IF we take the Admiralty connection as a good one, the other possibility is testing of cables destined for underwater signals/comms. The date is right in the hot part of the cold war, and elements of passive listening devices and submarine shenanigans were of course kept very dark.

Radio Wrangler · 11th Nov 2016, 8:26 am

perhaps a display of expected range of a shell from a large gun, whether a self-propelled land one (E.G. Abbot SPG, which looks like a tank) or a naval one?

David

Andrewausfa · 11th Nov 2016, 10:16 am

I can't recall seeing something like that in a British AFV, to any gunnery it would be like putting a 1/4" dial on a Short Wave set.

Andrew

M0FYA Andy · 11th Nov 2016, 10:22 am

I would imagine that a small meter like this one is likely to have come from a Test Set for some item of Admiralty equipment.

Andy

G4YVM David · 11th Nov 2016, 4:54 pm

Could it be wire paid out when using a wire guided torpedo?
D

Skywave · 12th Nov 2016, 1:17 am

I'm putting my bet on the suggestion in post #3: to be used to supplement a 'scope trace in a ground-based Radar station, e.g. Chain Home. It's a pity M.G. Scroggie isn't with us any more: he would have known with certainty.

Al.

G4YVM David · 26th Jan 2017, 2:47 pm

I was reminded of this thread when I watched a short fim today. Have a look at the link (its a youtube film) and go to time 2:36. There's a device there which is new to me...where is it from?

https://www.youtube.com/watch?v=UTO0ogdNMdY

The film is a little odd...you dont have to watch it all

david

ms660 · 26th Jan 2017, 4:50 pm

I think this might be the original:

http://pa0pzd.com/airforce/aaf-altit...vers/bc-788-c/

Don't ask me how I found that.

The AR88 knobs were a clue.

Lawrence.

10th Nov 2016, 6:32 pm	#1
The Philpott Dekatron Join Date: Aug 2016 Location: Colchester, Essex, UK. Posts: 4,108	Mystery metrology question ...What is it? I am advised that (a) former owner was connected with the GPO and also with Tank warfare. Gun laying? cable laying? Depth measurement? (Probably not the latter as it has no ad.patt. reference) It is quite small and has an FSD demand of 1mA. When protected with 8.2kohm it gives an FSD of 9volts, and is likely to end up in use as a voltmeter or a petrol contents gauge Attached Thumbnails

10th Nov 2016, 7:28 pm	#2
paulsherwin Moderator Join Date: Jun 2003 Location: Oxford, UK Posts: 27,970	Re: Mystery metrology question It could be from a GPO reflectometer. Was GPO kit of that era marked with a broad arrow?

10th Nov 2016, 8:41 pm	#4
The Philpott Dekatron Join Date: Aug 2016 Location: Colchester, Essex, UK. Posts: 4,108	Re: Mystery metrology question Could be radar (but a ground based set as it has no backlighting?) Time Domain Reflectometry a possibility. The compactness, light weight and surface mount flange hint at portable equipment and simplicity of quick testing by substitution..

10th Nov 2016, 8:44 pm	#5
bluepilot Heptode Join Date: Feb 2010 Location: Duffort, Gers, France Posts: 714	Re: Mystery metrology question If you google model 909 meter you'll find all sorts of examples with various scales. This one appears to have been part of a range finder. Maybe it was used to find the range of your enemy so a tank could shoot at him? __________________ Stuart The golden age is always yesterday - Asa Briggs

10th Nov 2016, 8:55 pm	#6
AC/HL Dekatron Join Date: Nov 2003 Location: Heckmondwike, West Yorkshire, UK. Posts: 9,642	Re: Mystery metrology question I thought AP meant Admiralty Pattern, but Airforce and Army also fit! Either way it's possibly for test equipment of some description. 7000 yards is about 6.4km or 4 miles.

10th Nov 2016, 7:39 pm	#3
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,536	Re: Mystery metrology question AP..... suggests airforce. Radar rangefinder readout? __________________ ....__________ ....\|____\|\|__\|__\_____ .=.\| _---\__\|__\|_---_\|. .........O..Chris....O

10th Nov 2016, 8:59 pm	#8
Nymrod121 Nonode Join Date: Apr 2012 Location: Worcestershire, UK. Posts: 2,052	Re: Mystery metrology question Might the reference be associated with an 'Air Publication' document? Richard (trh01uk), perhaps you can advise ... Best wishes Guy __________________ "What a depressingly stupid machine." [Marvin: HHGTTG]

10th Nov 2016, 10:35 pm	#10
M0FYA Andy Nonode Join Date: May 2007 Location: Preston, Lancashire, UK. Posts: 2,511	Re: Mystery metrology question I am totally confident that 'A.P.54959' on the dial means 'Admiralty Pattern 54959'. 'A.P' meaning 'Air Publication' is never seen as a reference on an item of hardware, but as the reference (with accompanying digits) on a document. The Stores Reference for an Air Ministry or RAF meter would be typically 5Q/xxxx or 10A/xxxx Andy

10th Nov 2016, 11:44 pm	#11
The Philpott Dekatron Join Date: Aug 2016 Location: Colchester, Essex, UK. Posts: 4,108	Re: Mystery metrology question Andy I suspect you are correct. I was looking for AD PATT at the very least but as the meter is very small AP is understandable. Finding a reference to 54959 is proving a challenge though. There is a good reference to WW1 numbers but later ones, no such luck. I am winging it a bit, but Gunlaying wise this might correspond to the range of the guns on a small vessel- eg corvette.

11th Nov 2016, 12:04 am	#12
Oldelectronics Heptode Join Date: Jan 2016 Location: Nottinghamshire, UK. Posts: 676	Re: Mystery metrology question Don't think its off a tank early on it was normally done with mk1 eyeball most early tanks had a limited maximum range against another tank on a Sherman for example about 800 metres. Then on more modern tanks like Chieftain they then used a ranging gun and today laser and ranges increased (starting with Centourian and its 105mm gun) after Centourian and onto Chieftain ranges were measured in metres (Certainly at the start of the 70s) not much help sorry!

11th Nov 2016, 12:38 am	#13
The Philpott Dekatron Join Date: Aug 2016 Location: Colchester, Essex, UK. Posts: 4,108	Re: Mystery metrology question IF we take the Admiralty connection as a good one, the other possibility is testing of cables destined for underwater signals/comms. The date is right in the hot part of the cold war, and elements of passive listening devices and submarine shenanigans were of course kept very dark.

11th Nov 2016, 8:26 am	#14
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,902	Re: Mystery metrology question perhaps a display of expected range of a shell from a large gun, whether a self-propelled land one (E.G. Abbot SPG, which looks like a tank) or a naval one? David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

11th Nov 2016, 10:16 am	#15
Andrewausfa Octode Join Date: Dec 2010 Location: St Ives, Cambridgeshire, UK. Posts: 1,180	Re: Mystery metrology question I can't recall seeing something like that in a British AFV, to any gunnery it would be like putting a 1/4" dial on a Short Wave set. Andrew __________________ Invisible airwaves crackle with life. Or they should do. BVWS Member

11th Nov 2016, 10:22 am	#16
M0FYA Andy Nonode Join Date: May 2007 Location: Preston, Lancashire, UK. Posts: 2,511	Re: Mystery metrology question I would imagine that a small meter like this one is likely to have come from a Test Set for some item of Admiralty equipment. Andy

11th Nov 2016, 4:54 pm	#17
G4YVM David Heptode Join Date: May 2014 Location: Salisbury, Wiltshire, UK. Posts: 998	Re: Mystery metrology question Could it be wire paid out when using a wire guided torpedo? D

12th Nov 2016, 1:17 am	#18
Skywave Rest in Peace Join Date: Jun 2006 Location: Chard, South Somerset, UK. Posts: 7,457	Re: Mystery metrology question I'm putting my bet on the suggestion in post #3: to be used to supplement a 'scope trace in a ground-based Radar station, e.g. Chain Home. It's a pity M.G. Scroggie isn't with us any more: he would have known with certainty. Al.

26th Jan 2017, 2:47 pm	#19
G4YVM David Heptode Join Date: May 2014 Location: Salisbury, Wiltshire, UK. Posts: 998	Re: Mystery metrology question I was reminded of this thread when I watched a short fim today. Have a look at the link (its a youtube film) and go to time 2:36. There's a device there which is new to me...where is it from? https://www.youtube.com/watch?v=UTO0ogdNMdY The film is a little odd...you dont have to watch it all david

26th Jan 2017, 4:50 pm	#20
ms660 Dekatron Join Date: Apr 2011 Location: Cornwall, UK. Posts: 13,454	Re: Mystery metrology question I think this might be the original: http://pa0pzd.com/airforce/aaf-altit...vers/bc-788-c/ Don't ask me how I found that. The AR88 knobs were a clue. Lawrence. Last edited by ms660; 26th Jan 2017 at 4:58 pm.