Rescued Test Equipment
 

Following on from an earlier thread post in "General Vintage Technology" this morning("Sad Times") - Have had a chance to examine some old test equipment I've never seen before :-

a) Wee bakelite "Spike" Voltmeter - DC 3V - - Z4/ZD 00110 written on leather case. No maker's name.

b) Wooden cased "Test Set Demolition Mk.1 (W.G.P.)". From WW2 according to internet research. No maker's name.

c) Wooden cased "Capacity Measurer" made by The P & B Engineering Co. Ltd. of Crawley, Sussex. Bit of rust & corrosion due to ancient EverReady torch battery left inside. But hopefully it'll clean up.

d) Wooden cased (Variac ?) - just "Rotary Regavolt" written on central dial(0 - 110V), and there is a 4,8, & 30V selector switch. No maker's name.

Big crud, dirt & scratch removal project for the three wooden cases. I'm desperate to research & delve inside the demolition test set and the capacity measurer.

Any advice please, most appreciated.

Regards, David

Re: Rescued Test Equipment
 

More pictures.

Re: Rescued Test Equipment
 

Hello David, I think the Spike voltmeter is for measuring the voltage of lead acid cells.We had one similar to yours for check stacker truck batteries (1959 era) to see if they needed an equalising charge. Ted

Re: Rescued Test Equipment
 

the spike voltmeter is a cell testing voltmeter. It looks very much like the Evershed and Vignoles cell tester that was launched in 1902; but still in production well into the 40’s. saying that, normally the Evershed and Vignoles name would be on the scale plate. Are there any scale names or numbers?
I have one from 1933

Re: Rescued Test Equipment
 

The 'capacity measurer' looks like an AC bridge circuit to me.

Re: Rescued Test Equipment
 

Yep, I've used lead/acid cell testers in the past - big bulky wooden handled things, but nothing as neat as this wee bakelite tester.
The demolition tester & the capacity "measurer" intrigue me. Am dying to delve inside. Plus restoring the manky wooden cases is going to be quite a challenge.

Regards, David

Re: Rescued Test Equipment
 

Is that demolition tester not just a continuity tester for series connected detonators.
If so it should have a companion with a classic plunger to fire the charges.

Re: Rescued Test Equipment
 

I’ve got one of those demolition test set things too! They look really nice with the case all polished up.

Regards
Lloyd

Re: Rescued Test Equipment
 

Hi David, I have both the detonator test set and the spike voltmeter.
Spike used on GPO and FLT batteries etc.
Detonator tester is a low current device to check circuits without setting them off. Actual "exploder" is separate part.

Variac unit could have a limited range of "rotation" and taps on the winding to give a finer adjustment.

Cheers, Ed

Re: Rescued Test Equipment
 

I found the detonator test set interesting, since I do some engineering support for an explosives ordnance disposal co. particularly as I was called on to make an initiator a few years back. Mine is based on a Microchip PIC and combines line test prior to allowing the initiating pulse, which is required to be a minimum of 1 amp into a maximum of 200 Ohms. Things are a little easier with modern electronics!

Re: Rescued Test Equipment
 

Les, PM sent. David

Re: Rescued Test Equipment
 

The "Capacity Measurer" seems to be an ancient version of a TDR. Distances of up to 1000yds can be measured for cable damage. The ten taught strands act as a calibrated standard & the probe is stroked along them until a measured comparison is obtained. The battery compartment contains a simple buzzer signal source. Then there is the Brown's Earpiece - a null detector ?

Regards, David

Re: Rescued Test Equipment
 

Detonator tester, done that with a tester, sweat or what...8-o It happened when the electric dets failed to go off in a tunnel round I was drilling and blasting down a tin mine with the boss man, there was always two of us drilling using two machines side by side, a young early twenty something me as a relative newbie, and the boss man aka "the machine man" but only one of us was allowed to go in to test for a misfire...I was given the short straw! It was sweaty enough as it was, 2,000 ft down then a good quarter of a mile into tombstone granite via a pokey tunnel barely 6Ft high in places, temp. at the face somewhere around 80 F on a good day.

A typical tin mine tunnel blasting round where I worked back then would be about 33 holes so 32 dets for a five hole burn cut, used dets with different delays to get the correct breakout sequence from the reamer hole otherwise impressive bangs but everything hangs up so no pay dirt, usual fault finding procedure to find the offending culprit, this way that way, this way that way until it's found, only problem was sticking a new det into the charge, can only be done from the face end of the charged hole and not the back end when you are on contract and got a two man night shift mucking crew to support, that means the primer is no longer at the back of the hole 8-o.

Having said that it's not as scary as going to attend a misfire due to a safety fuse not going off, now that's really brow dripping stuff....

Lawrence.

Re: Rescued Test Equipment
 

Well, thought I'd concentrate on just the "Capacity Measurer" meantime. Hopefully, some Demolition/Explosives vintage enthusiast will take the Demolition Test Set off my hands, and I'll leave the Rotary Regavolt for while.
Capacity Measurer - I've drawn up a circuit diagram, & cleaned up the resistance "Harp" - quite tuneful actually. All wiring is intact with un-perished insulation. The buzzer works, but I've yet to test the earphone, or connect to some long lengths of wire an see how accurate the whole set-up is. I've sent an email to P & B(Yes - they're still on the go), to see what's in their archives, but no reply yet.
Biggest challenge will be the mahogany wooden case. The original hinge/stay assemblies are broken, and the exterior is badly scratched & filthy.

Regards, David

Re: Rescued Test Equipment
 

Help please. Back on the 16th Feb I posted a picture(post2, picture 2) containing a rotten Every Ready 4.5V battery, the old torch type.
There are plenty modern ones for sale on eBay - Energizer & Varta for about £5. And the RE WS19 Group has an excellent link for downloading Every Ready's range of vintage radio battery's replica scans. But, is there a download for these old torch/lantern batteries ? Maybe I need to go to specsavers, but haven't found one on the Forum's "Search".

Regards, David

Re: Rescued Test Equipment
 

The side bar on those batteries is that they contain three 1.5V cells in series. And each individual cell is the correct size for the battery in the oldest of the AVO multiminors.

So you buy one, split open the outer case and you get three batteries for Multiminors.

£3.62 from RS

https://uk.rs-online.com/web/p/speci...eries/7904697/

https://docs-emea.rsonline.com/webdo...6b81583229.pdf

Craig

Re: Rescued Test Equipment
 

Thanks Craig for the RS link. A bit cheaper than the eBay ones. Sadly, our local RS Depot has closed down, so might order by phone or online. Yep, right enough, those batteries do break down to individual cells for vintage AVO T/Eq, particularly the CT446 Tr. Tester which needs 16!
But, its the pdf download scan of the original Every Ready I'm needing - to wrap around an RS, or Varta modern version. As you can see from my picture, the original battery's cardboard is too far "manked" to re-stuff.

Regards, David

Re: Rescued Test Equipment
 

Before I can put the buzzer & a new battery back in the lid I'll need to do a heap of work on the wooden case. Earlier pictures will show how filthy & deeply scratched it is. Almost skip-able some might say. To my inexperienced eyes, its beyond "razor blading". So this afternoon I've made a start on the lid. Lovely mahogany underneath the stained & scratched surface. So lots of rubbing down with various grades of oxide & glass paper & wire wool. Much rubbing with meths soaked kitchen role paper between each change of abrasive grade. Still more to do, but a G&T beckons before dinner.
Picture 2 shows the lid on the right & the base(still to be done) on the left.

Regards, David

Re: Rescued Test Equipment
 

They don't make boxes like that any more! Good effort to scrub it up whilst maintaining patination. I have a similar box that someone has over-restored and it doesn't look..right.

Dave

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Right enough Dave, this wooden cased item & the other rescued ex Hydro-Electric Board ones have spent their entire life of 50 - 60 years in the back of a Landrover or 3ton Bedford, I suspect. Definitely not a pampered existence in a workshop.
I had a shufti through "Cabinet & Chassis Restoration" & saw a couple of recent threads which I would aspire to, but haven't the skills :- Murphy A40C owned by ukol & professionally restored, and a Murphy A242 restored by stuart R. Lovely jobs. I've had 3 Murphy's through my hands in recent times, but thankfully they only had minor-ish cosmetic problems.
However, these old items did belong to an old deceased HEB chum, I did work for the HEB for a few years, and the HEB do give me a fine pension in my retirement years. So if I cant find homes for them with keen collectors, I'll just keep them on a display shelf, having spent many enjoyable hours restoring them.

Regards, David