Hello TEA folks,
this is a follow-up to my
Rohde & Schwarz UGZ BN 1100 voltmeter.
Today, this manual showed up at my doorstep:
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:
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!
This is a description of the display and which lamp does illuminate which digit/symbol.
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.
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.
This is the block diagram and as you can see on the lower right, the meter has been synchronized with the 50Hz mains.
This is one of two timing diagrams, this one is for calibration.
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.
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.
And last but not least, the module with the voltage reference, made by two Ge-zeners (the two black blocks on the left).
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.