Hello TEA folks,
this is a follow-up to my
Rohde & Schwarz UGZ BN 1100 voltmeter.
Today, this manual showed up at my doorstep:
![](https://i.imgur.com/1aQnkkr.jpg)
It is in a very good condition, given it's age. The colouring of the top cover is a bit worn out and yellow-ish.
The paper in the inside has also this yellow-ish colour but the paper itself is really thick! I'd estimate
something around 100g/m²!
I'll do a proper scan of all pages but this could be a bit difficult because some pages are significantly bigger
than my A4-sized scanner. I think, gimp could merge the results electronically but I have to find out first
how to do that. In the meantime here are some examples of the inside as hi-res pictures.
Sorry, the manual is completely in German but I hope you'll get meaning of it.
Let's start with the specifications of this meter. Here are the data-sheets:
![](https://i.imgur.com/PPDZQlm.jpg)
Fault tolerance: +/- 0.02% from the measured value and +/- 0.01% full scale.
Not bad for a meter from
1958!
Edit: sorry, mixed this up with my R&S counter. The UGZ is from 1962/63.
This was a big advantage back in the days: once the meter has been calibrated, it doesn't need to be calibrated again!
![](https://i.imgur.com/9AUV1bM.jpg)
This is a description of the display and which lamp does illuminate which digit/symbol.
![](https://i.imgur.com/u4CYPZj.jpg)
The manual contains a lot of reasoning and explanations about how it is working. Here we have a desription of one
of the core parts: the so called "binary potentiometer". If you are looking at the schematics one can see at "Z" another
core part implied: the chopper amplifier.
![](https://i.imgur.com/a0iNETS.jpg)
While looking through the parts lists, this caught my attention: three silicon transistors have been used in this unit
from the late 50's! A BDY10, a BSY52 and a BFY19. Wow, I didn't thought that they were that old.
![](https://i.imgur.com/xn1fTcA.jpg)
This is the block diagram and as you can see on the lower right, the meter has been synchronized with the 50Hz mains.
![](https://i.imgur.com/Bs9E7YC.jpg)
This is one of two timing diagrams, this one is for calibration.
![](https://i.imgur.com/AfgHXkT.jpg)
As mentioned before, there has been used a chopper amplifier in the UGZ. This is the schematics of it.
It is made with a nuvistor (7895) which I've ordered two of them right away, because the manual states,
that these nuvistors should be replaced after some time.
![](https://i.imgur.com/OVDVM8S.jpg)
A lot of flip-flops have been used in this meter. This is one of the counter modules and I think the flip-flops are set up as a shift-register.
![](https://i.imgur.com/Mei0v5i.jpg)
And last but not least, the module with the voltage reference, made by two Ge-zeners (the two black blocks on the left).
![](https://i.imgur.com/OGmaeVR.jpg)
When I've done the scanning of this manual I'll upload it to KO4BB's website for easy access.
Hope, you've enjoyed this update, now I'm off, have to read a manual.
![Grin ;D](https://www.eevblog.com/forum/Smileys/default/grin.gif)