Echoes from a distant past
Part six - The Nordmende digital multimeter DIVO 3355 (with Nixie tubes!)
Part one - Siemens Rel. send. 22bPart two - The Two TransformersPart three - The Rohde & Schwarz NGU laboratory power supply unit for vacuum tubesPart four - The Rohde & Schwarz Vacuum Tube Meter URI BN 1050Part five - The Rohde & Schwarz UVN BN 12001 NF MillivoltmeterPart six - The Nordmende digital multimeter DIVO 3355 (with Nixie tubes!)
Hello,
today I'd like to introduce the Nordmende DIVO 3355 digital multimeter. I think, DIVO stands for DIgital VOltmeter, but the 3355 is able to measure voltages, currents and resistance.
It is a four-digit meter with a polarity display. The AD converter is a dual-slope type and the voltage reference is a 1N825 diode. The newest date code I was able to find dates from 7508, so my instrument has been built earliest mid of 1975.
The measurement ranges are:
Voltages:
1V, 10V, 100V, 1000V with a resolution of 0.1mV, 1mV, 10mV, 100mV
Input resistance is: AC 3MOhm, DC 50MOhm
Current:
1mA, 20mA, 100mA, 1000mA, 3A with a resolution of 0.1µA, 1µA, 10µA, 100µA, 1mA
Resistance:
10kOhm, 100kOhm, 1MOhm, 10MOhm, 100MOhm with a resolution of 1Ohm, 10Ohm, 100Ohm, 1kOhm, 10kOhm
The Nixie tubes are 4x ZM1000 and one ZM1001 for the + and - sign.
The manual with all schematics and calibration instructions can be found here:
https://elektrotanya.com/nordmende_divo_3355_digitalvoltmeter_sm.pdf/download.htmlBut now for the pictures:
Front side with the power cord, back side, some input jacks for connecting earth buried under dust, the serial number #2570
Top and bottom view.
Mains transformer, PSU with looking-good electrolytic cap, some other electrolytic caps hiding under the transformer
1MHz crystal oscillator, some TTL logic, Nixie tubes with driver ICs
Input with fuse, some thermocoupled transistors.
And how does it perform?
I did a quick check with my DMMCheck to find out.
input shortened 0V, 5V and 1mA from the DMM check.
Resistance: 1kOhm, 10kOhm, 100kOhm
The meter is a bit off in all ranges. I think, some calibration and checking for drifted parts are on order.
Replacing the electrolytic capacitors as well. The meter contains also lots of ugly carbon resistors which needs to be checked. Ungh...
![Tweak :-/O](https://www.eevblog.com/forum/Smileys/default/smiliey_cal.gif)
But it is a nice bench meter with some sexy-glowing Nixie tubes. In my opinion a showpiece for every bench.
![Azn ^-^](https://www.eevblog.com/forum/Smileys/default/azn.gif)
I hope you've enjoyed this teardown.
Thank you for watching.