VK2-16 very old analog electrometer from Minsk. - Page 1
Forum section: electronics / general

author: bsw_m
author_rank: Frequent Contributor
timestamp: November 13, 2020, 02:34:53 am
content: I got myself a toy like VK2-16. It was purchased not for work, but as history and to see how the development of the design went, etc. My device was produced in 1976, i.e. the device is already 44 years old.The device was developed in the 60s (presumably in the period 64-66, but I do not have exact data), at the SKTB at the Molotov plant(later named BELVAR), Minsk. In 1971 this SKTB was separated from the plant and transformed into MNIPI itself.Perhaps this is the first electrometer from Minsk, alas, I have no information about the presence of earlier devices.The device is built on a DRK-3 dynamic capacitor, developed by Konstantin Sergeevich Shuklin.It can measure voltages 1mV-30V and currents, with a lower range of 1E-15A.The resistors are switched by a ring on the VIB unit (remote measuring unit) and have ratings 1E12, 1E10, 1E8 Ohm.For charge measurement this device using custom 100pF air capacitor.The device was bought as non-working, after a small and supposed even before receiving the device, repair (all the parts remained native, the DRK-3 required restoration). Has earned and has shown very good results in metrology. After repair I have tested the device on the 1pA range and got very encouraging results. The error was only 3% with the declared error in the specification 10%I'll do the teardown later.

author: bsw_m
author_rank: Frequent Contributor
timestamp: November 13, 2020, 02:43:36 am
content: Quote from: shodan@micron on November 13, 2020, 02:41:05 amThat no problem!there are only 2 components: pure alcohol, dynamic capacitor DRK-3

author: bsw_m
author_rank: Frequent Contributor
timestamp: November 13, 2020, 12:19:14 pm
content: For first test I use 1pA current. This is very big current.What about 1fA current and range? No problem!Next I try 0.1fA and 0.01fA currents. But I need connect other differentiator to NK4-1 for generate that currents

author: bsw_m
author_rank: Frequent Contributor
timestamp: November 13, 2020, 12:53:58 pm
content: So, I'm changed differentiator on NK4-1 and generate test currents 100aA and 50aA.Measurement results:

author: bsw_m
author_rank: Frequent Contributor
timestamp: November 13, 2020, 03:36:40 pm
content: Teardown of the DRK-3 dynamic capacitor. The heart of this metter.Amber is used as an insulator for central pin.

author: Vgkid
author_rank: Super Contributor
timestamp: November 14, 2020, 04:17:44 am
content: Thanks for the teardown.

author: the_light
author_rank: Newbie
timestamp: July 13, 2022, 08:36:32 pm
content: Thank you for this post ! I've been looking for the manual for the VK2-16 all over the internet. Is there any change you might share (if you have it ).

author: guenthert
author_rank: Frequent Contributor
timestamp: July 13, 2022, 11:53:38 pm
content: Quote from: bsw_m on November 13, 2020, 03:36:40 pmInteresting. There's plenty of amber to be found at the coast of the baltic sea and it's much easier to work with than sapphire, I'd think. And it's just fitting to use ēlektron in a current measurement tool.

author: bsw_m
author_rank: Frequent Contributor
timestamp: July 14, 2022, 08:26:32 am
content: Quote from: the_light on July 13, 2022, 08:36:32 pmUnfortunately, my search for any documentation on this device was not successful. This device was mentioned in the book "Electrometry Technique", but the circuit diagram given there does not correspond to reality. After getting acquainted with this device and satisfying my curiosity, the device was given to the Belvar museum.

author: bsw_m
author_rank: Frequent Contributor
timestamp: July 14, 2022, 08:31:03 am
content: Quote from: guenthert on July 13, 2022, 11:53:38 pmAmber has better insulating properties than sapphire. But it also has its disadvantages - first of all, it is fragile. But if it is easier to access than sapphire, it can be used and achieve good results.

author: the_light
author_rank: Newbie
timestamp: July 14, 2022, 06:34:42 pm
content: Thank you for your responses to my post guys. I looked at the "technique of electrometry" . O dear !!! This instrument had a sensitivity of less than a femtoamp while being built with vacuum tubes !!!?Beautiful !!! If I had a VK2-16 I would pray to it and burn incense to it every day !! I know it doesn't get better than the V7-45 and V7-57 but the pure analog nature of the VK2-16 just does it for me!! Cheers !!

author: bsw_m
author_rank: Frequent Contributor
timestamp: July 14, 2022, 08:34:59 pm
content: I think you can try to find a Cary 401, which I suspect will be just as good as the VK2-16, and probably better.

author: ZhuraYuk
author_rank: Regular Contributor
timestamp: August 19, 2022, 08:52:44 pm
content: Here are photos of input commutator of external measurement block. Gold plated needles are touching gold plated rod which goes directly into vibrating capacitor. All insulation is amber.

author: the_light
author_rank: Newbie
timestamp: September 09, 2022, 01:11:28 am
content: Gorgeous !! Beautiful !! Thank you for posting this.