Help to further identify these plug-ins (Ru)

[JM2]

Looking farther afield, has anyone experience of the apparatus these were(/are) used on.
Asking for a friend, be interested if we found the photos/references of the original kit.

The are simple resistors inside the easy to handle plug-in modules (large pins about 1½" apart), albeit I think way off their original marked values now.

They are not series resistors for a test meter setup (at least the values don't fit for moving coil meters), I supect they are for a demonstation/student use PSU setup. I can approximate the printed values c.f. resistance if an constant current OP Amp setup was used (although with the values measured seem rather approximate).

Box marked up in Cryllic - not my forte but from the Moscow State Univ. dated 1970 (but suspect a somewhat older design).

20190202_101602smr

• JM2
• 5 Feb 2019

MSU-1 (r)

 

[JohnW2]

... The are simple resistors inside the easy to handle plug-in modules (large pins about 1½" apart), albeit I think way off their original marked values now. .... They are not series resistors for a test meter setup (at least the values don't fit for moving coil meters), I supect they are for a demonstation/student use PSU setup. I can approximate the printed values c.f. resistance if an constant current OP Amp setup was used (although with the values measured seem rather approximate). Box marked up in Cryllic - not my forte but from the Moscow State Univ. dated 1970 ...

Interesting! What sort of resistances are we talking about?

Kind Regards, John

 

[JM2]

The DCs 7.7Ω to 23.1kΩ (there is a foreigner in there - 2x 25v), the AC plugs 0Ω (1v is s/c) to 20.1kΩ.

This chart is Ω (Y) against V (X) labelled plugs.

MSU Plug Chart

• JM2
• 5 Feb 2019

Plug restistance vs voltage labels

 

[JohnW2]

The DCs 7.7Ω to 23.1kΩ (there is a foreigner in there - 2x 25v), the AC plugs 0Ω (1v is s/c) to 20.1kΩ.
This chart is Ω (Y) against V (X) labelled plugs.

Thanks.

I'm not sure why you don't think that they might not be series resistances for voltage measurement - the DC ones would be almost dead right to give the indicated voltage at FSD with a meter with 1mA FSD, and similarly for AC with a ~2.5mA FSD meter. In the later case, it's interesting that 2 x sqrt(2) is ~2.5, which could possibly be relevant.

Kind Regards, John

 

[JohnW2]

The DCs 7.7Ω to 23.1kΩ (there is a foreigner in there - 2x 25v), the AC plugs 0Ω (1v is s/c) to 20.1kΩ.
This chart is Ω (Y) against V (X) labelled plugs.[/GALLERY]

Please see my reply in this thread (click here) .

I don't pretend to understand what is going on, but maybe I am not meant to be able to understand!

Kind Regards, John
Edit: Ah - my original reply now seems to be visible to everyone. I continue not to understand

 

[DetlefSchmitz]

I must admit I assumed it was the word 'foreigner' which set it off but, odd that the original use of the work wasn't flagged.

it might have been triggered by the preponderence of special characters, in the original post, and when it was quoted, which are unusual. Both were picked up. But the swift and efficient mods approved them in minutes.

You're welcome.

Another mod.

 

[JohnW2]

I must admit I assumed it was the word 'foreigner' which set it off but, odd that the original use of the work wasn't flagged.

Ah. It looks as if the "original use of the word" probably was 'flagged' ....

MOD: It was the quoted text, also moderated. End.

I confess that I hadn't originally considered the possibility that the quoted text could have been an issue but, frankly, even if I had considered that possibility, I don't think that it would have occurred to me that that particular word (rather than a derogatory 'synonym') would, in itself, be regarded as being a particular problem.

I suppose the test is the message you've just posted, and my reply here which quotes it, since both contain 'that word'.

Kind Regards, John
Edit: well, this one does not seem to have triggered the alogirithm (maybe it's been 're-trained?!), even though it quoted your use of 'that word',

 

[ericmark]

I would have guessed some sort of Wheatstone bridge?

 

[JM2]

Thanks.

I'm not sure why you don't think that they might not be series resistances for voltage measurement - the DC ones would be almost dead right to give the indicated voltage at FSD with a meter with 1mA FSD, and similarly for AC with a ~2.5mA FSD meter. In the later case, it's interesting that 2 x sqrt(2) is ~2.5, which could possibly be relevant.

Kind Regards, John

Err, my maths went a bit off there when I found a mismatch at 25v (dc - only worked with the dc plugs) [Oh to have had a 50v to use.]
So indeed, error withstanding, meter resistors. Meter in question is 1mA (fsd) approx 300Ω device (quite normal I'd have thought for a student's demo kit).

Does anyone have any pics/names/experience of the setup used ? Pins ~ 35mm spacing.
And if anyone has a 50v (dc) serial group 3103 I'd like to hear from them! [the rest match with the box]

 

[JohnW2]

Err, my maths went a bit off there when I found a mismatch at 25v (dc - only worked with the dc plugs) [Oh to have had a 50v to use.] So indeed, error withstanding, meter resistors. Meter in question is 1mA (fsd) approx 300Ω device (quite normal I'd have thought for a student's demo kit).

Indeed - as I said, at least for DC, the resistors are almost dead right for voltage measurement with a 1 mA meter. As you say, a 1 mA movement sounds very credible for 'classroom' work - analogue moving-coil multi-meters typically had 50 μA FSD meters, but that could well have been regarded as too 'fragile' for students to play with!

Kind Regards, John

 

[bernardgreen]

from a forum about East German computors and electronics

I would also say measuring range connector for a school voltmeter which had a slightly larger design, for the purpose of recognizability. I also own similar devices from GDR production, where with the measuring range plug the appropriate scale was brought into the device.