Solartron JM 1860 Time Domain Analyser and ZM 1162 Nixie tube

[Ken G3XSJ]

I recently acquired this lovely instrument dating from about 1969 according to the ceramic chip date codes. I do not know what it was used for but bought it as it reminds me of the very first DVM that I used.

A long shot, does anyone have a manual or more information?

It looks like it may be working but one of the ZM 1162 Nixie tubes is cracked. These are plug in devices, not the usual wire ended tubes. Any chance of a potential replacement please?

Thanks, Ken

[karesz*]

Hi Ken,
please select one source for your Nixi`s and here is some citation over JM-1860, than such article "what Time-Domaine_Analysis is"...
rgds, Karl

[buggies]

Originally Posted by Ken G3XSJ

I recently acquired this lovely instrument dating from about 1969 according to the ceramic chip date codes. I do not know what it was used for but bought it as it reminds me of the very first DVM that I used.

It was often used in conjunction with the JM1861 Pseudo Random Signal Generator. I never did really understand what the beast did - see the 3 pages of "introduction" attached. Note that the chips used are DTL not TTL.
The service manual is a bit "well used" with the odd coffee stain and pencilled notes. It is over an inch thick and weighs about 1.2kg so would be about £3 postage.
I found a NOS ZM1162 - only have one, the others are ZM1162A which do not have the two NC pins in the middle. Tested ok with 250v and 100k on each pin.
I was going to auction the manual but will hold off if you send me a PM for details.

[mark_in_manc]

A manual containing pages full of integrals I like it...must be something like a non-graphical Fourier analyser?

[buggies]

Urmm... probably.
Pic from shortform catalogue along with its 1861 mate.

[mark_in_manc]

Blimey, that's ringing some vague, vague bells. I think it's (and here's a sentence you don't get to say too often) a physical manifestation of the Wiener- Khinchin theorem

I would guess that it came about because doing it that way might consume fewer computational resources than doing it in the frequency domain as a (Fast) Fourier Transform. I think it's a bit earlier than the earliest Bruel & Kjaer FFT analyser I can remember from the place I used to work.

Before that it was all 1/1 or 1/3 Octave Band analysis. And now we can do really long FFTs for free in share-ware. And people don't know how to interpret the data

[Ken G3XSJ]

Thank you everyone for your help. I didn't hold out much hope on receiving any response on this one as it is clearly very specialised and the market was probably limited. But there we are, there's usually someone out there who has knowledge of obscure equipment.

I'll try to PM George shortly regarding the offer of a manual and tube and thank you all again for the interesting views and advice. It is appreciated, as is this superb platform for sharing our passions !

Regards, Ken G3XSJ

[mark_in_manc]

It claims to be able to measure the impulse response of an LTI (linear, time-invariant) system. So when you get it going, see if you can use a series RLC circuit as a test network. You should get a decaying sinewave as a result, whose period is 1/{(1/(2pi))*sqroot(1/LC)}. As R gets smaller the length of the decaying sinewave will increase - that is, the decay rate will reduce.

[buggies]

As there is a bit of interest in the operation, I scanned the Principles of Operation section - but the 7 page pdf was too large for the forum (and probably minority interest anyway) so it is here:-
https://www.dropbox.com/s/1sucwraxr1...0_001.pdf?dl=0