German Test Meter - Age?

[Sparky67]

Hi all,

I have had this test meter in a drawer for many years and have always wondered what it is exactly, its approximate age - and its history.

Can anyone tell me what it is, and how old it could be please?

Many thanks.

Martin
G4NCE

[G6Tanuki]

It looks like a battery-testing meter for testing single cells. The button on the side would appear to apply a resistor (the big circular black piece on the back, with curly wires going to it) across the load, and the health-or-otherwise of the battery is then indicated by seeing how far the needle drops back.

I'd say it dates from the early-1930s.

[David G4EBT]

Yes, I think it was to check the state of charge of a 2 Volt accumulator, as used for pre-war battery valves with 2 Volt heaters.

I've just checked the literal translation of the wording on the dial from German into English and it is:

German: knopf gedrückt pfeile geben die untere grenze an neues element.

English: 'button pressed arrows indicate the lower limit of a new element'.

I take that to mean that when the meter is connected across a 2 Volt cell and you press the button, it will indicate the 'new' (ie, 'present') state of charge.

Quite a useful little gizmo in it's day I guess, though I think most radio owners tended to have a spare fully charged accumulator to hand, and knew when the one in use needed recharging due to the fall off in volume, so in effect, used the radio itself as an indication as to when the accumulator needed to be recharged.

Hope that helps a bit.

[eddie_ce]

Seasons greetings to all,

further to David's post, the 3rd line of text states that "the arrows denote the lowest (acceptable my addition) limits". The red arrow when the button is pressed (with load). The black arrow with no load.

Hope this helps.

[ms660]

A similar one here. dated 1916 apparently:

https://www.tmatlantic.com/upload/ib...6voltmeter.jpg

https://www.tmatlantic.com/e-store/i...EMENT_ID=18102

Just wondering if that logo is Siemens & Halske….

Lawrence.

[Joe_Lorenz]

Hello folks,

this instrument is definitely made by Hartmann & Braun, abbreviated H&B. Please see the logo here:

https://www.alte-messtechnik.de/hub/hub-6.htm

So the instrument is of the era 1901 to 1933, and I assume it's of the early 20s.

It is a battery tester, and the button gives load (resistor) to the test object, so you can read idle voltage and load voltage. Here is even more to read about it:

https://www.radiomuseum.org/r/hajose...iepruefer.html

I have always been a fan of H&B gear because of sturdy design and good quality. It is similar a fine quality as Rohde & Schwarz makes.

Kindest Regards,
Joe

[Joe_Lorenz]

Hello again,

I have just figured out that - believe it or not - the H&B company had taken record of every item until 1954. The engraved number on the dial can tell the time of manufacture!

See here what we find out:

https://www.alte-messtechnik.de/hub/skalennummer.php

Putting the serial number in here, it tells us the instrument was made in 1915 March!

So still older than I assumed!

A nice piece of history!

Kindest Regards,
Joe

[Sparky67]

Thank you all for your input on this meter and the translations of the text on the scale. My initial thoughts were 1940s so I am very surprised to hear it is much older - that serial number/date link was an excellent find Joe.

The meter feels very solid in the hand and the engraving on the rear is a nice touch. It has not been tested since I acquired it so that's now on the list of things to do. And then have a think about its longer-term future. It seems a shame to put it back in the drawer for another 20 years...

Thanks again.

All the best,

Martin
G4NCE

[Barnmead]

Thank you Joe for the serial number link. I now know my H&B insulation tester was made in October 1913 Brilliant!

[Silicon]

I thought the voltage of a single lead acid accumulator cell was 2.2V.

This is probably more suitable for zinc carbon dry cells or Leclanche wet cells.

Leclanche wet cells were used for doorbells and servant signalling systems.

[paulsherwin]

Similar 'pocket watch' meters seem to have been very popular in the first half of the 20th century. The commonest design was used to measure the voltage of a car battery.