Teardown: Russian/USSR LCR-bridge (warning: large pictures) - Page 1
Forum section: electronics / testgear

author: mzzj
author_rank: Super Contributor
timestamp: March 20, 2013, 08:31:37 pm
content: Time for something different, CCCP LCR-bridge. "IMMITTANCE METER E7-14"Manufactured in 1992, came here as a part of some surface-to-air missile systems deal.http://www.kalibr.com/en/ria-e7-14.shtmlAfter the collapse of soviet union the factory is now in the BelarussiaFront panel of the meter. Note "BNC-like" connectors that are almost identical to western BNC connectors but hardly mate between.Rear panel connectors. Possibly clone of GPIB-connector and bus ?Inside: plentiful of ceramic smd chips, pretty high-end.Some shielding boxes... full of worms

author: larry42
author_rank: Regular Contributor
timestamp: March 20, 2013, 09:41:04 pm
content: Wow, I'm always fascinated by the old USSR-era stuff , although if this is from '92 then they were using early-mid 70s technolgy (by Western standards). Amazing.PS I'd love to see a Russian VNA or spectrum analyser, if anyone has one...

author: mzzj
author_rank: Super Contributor
timestamp: March 20, 2013, 10:04:33 pm
content: Quote from: larry42 on March 20, 2013, 09:41:04 pmNot really a surprise.Story goes that quite often you had to design your equipment around whatever parts happen to be available. Sometimes this meant making logic circuits with thyristors....Anyone here familiar with those hermetic surface mount chips in ceramic packages?Must be crazy expensive.

author: casinada
author_rank: Frequent Contributor
timestamp: March 20, 2013, 10:14:48 pm
content: I'm sure is totally unobtanium to get replacement parts

author: Hydrawerk
author_rank: Super Contributor
timestamp: March 20, 2013, 11:24:50 pm
content: I have the Soviet H313 5MHz oscilloscope from 1982. It is crap so I do not use it.GoogleAnd picture I found on web... Because my H313 oscilloscope is buried somewhere in my cupboard... Note the small screen.Somebody made a video. Note the problems with synchronisation. It must be quite common at these scopes. The video was not made by me.H313??

author: Hydrawerk
author_rank: Super Contributor
timestamp: March 20, 2013, 11:32:42 pm
content: In Czech Republic, Tesla produced the BM595 LCR meter in the late 1980s. It is much more modern.

author: SeanB
author_rank: Super Contributor
timestamp: March 21, 2013, 05:11:26 am
content: Mzzj, careful of those ceramic packages, looks like most are from missile control boards and onboard computers, and have Beryllium oxide ceramic cases. From the build quality it probably will last until close to eternity, or until you get frustrated and hit it with a hammer.

author: mzzj
author_rank: Super Contributor
timestamp: March 21, 2013, 07:28:02 am
content: Quote from: SeanB on March 21, 2013, 05:11:26 amYup, I was thinking of beryllium oxide also. And some of the capacitors may as well be PCB-oil-in-paper typesLuckily beryllium oxide is not that bad unless you hit it with hammer.Why would I do that? Well, wait a second... This boat anchor stopped working 1 or 2 years ago and repair looks "challenging" so to say.While it was working it was reasonably nice piece of equipment to use.

author: SeanB
author_rank: Super Contributor
timestamp: March 21, 2013, 08:24:26 am
content: If it is not working post it to me, I need a nice boat anchor.

author: ConKbot
author_rank: Super Contributor
timestamp: March 21, 2013, 11:37:10 am
content: Quote from: mzzj on March 20, 2013, 10:04:33 pmThe chips (and most the other workmanship) looks spot on for what I was trained on for NASA-STD-8739. The chips come with the leads sticking straight out, and we had to use a rather expensive lead-forming machine to form the leads and trim them to the desired length. It was the only SMT part that we were trained on hand soldering.The wire loops holding down big components is a bit odd, the NASA std requires staking compound instead. (and who knows how much a the low outgassing staking compound they would require for space flight would cost ), and there are some smaller items which arent secured which could be, but this thing is definitely made to last.

author: GK
author_rank: Super Contributor
timestamp: March 21, 2013, 11:55:34 am
content: I have a piece of Australia made (AWA) test equipment from about the same time with very similar looking, white ceramic/beryllium? SMD chips on a logic board.

author: firewalker
author_rank: Super Contributor
timestamp: March 21, 2013, 12:01:08 pm
content: Any known semiconductor parts in the LCR?Alexander.

author: GK
author_rank: Super Contributor
timestamp: March 21, 2013, 12:14:23 pm
content: Quote from: GK on March 21, 2013, 11:55:34 amOK, I just went out to the shed and pulled the cover. Strange package for an otherwise rather plain and boring TTL board. The blue/purplish rectangle under each chip is actually a piece of cardboard. They are part of a 4-digit BCD up/down counter. Won't know for sure how they're wired until the service manual for this thing turns up.

author: SeanB
author_rank: Super Contributor
timestamp: March 21, 2013, 01:01:24 pm
content: Like this?crDSC01484bySeanB_ZA, on Flickr

author: peter.mitchell
author_rank: Super Contributor
timestamp: March 21, 2013, 01:18:41 pm
content: i want to see the transformer on the russian lcr bridge, is it potted or something?

author: mzzj
author_rank: Super Contributor
timestamp: March 21, 2013, 03:21:04 pm
content: Quote from: peter.mitchell on March 21, 2013, 01:18:41 pmYou can see it in the 6 th. picture. Large green lump on the left side.It looks like its potted, dipped in green "paint" or varnish or something like that.SeanB, what is that board?That board material looks similar to CCCP lcr-bridge. Can easily see traces inside the board and the entire board is more or less see-through.

author: SeanB
author_rank: Super Contributor
timestamp: March 21, 2013, 03:34:11 pm
content: Memory card for an avionics computer. Has one slightly faulty IC on it, guess which one it is.

author: PA0PBZ
author_rank: Super Contributor
timestamp: March 21, 2013, 09:58:12 pm
content: Quote from: SeanB on March 21, 2013, 03:34:11 pmJust guessing here.... the one with the guts on display?

author: reagle
author_rank: Unknown
timestamp: March 22, 2013, 03:55:26 am
content: The thing has 92 datecodes all over but is indeed looking like a much older design that they probably kept building forever.The micro chipset by the way is KR580VM80, a Russian 8080 clone, plus the peripheral chips 8055/8053 etc.

author: SeanB
author_rank: Super Contributor
timestamp: March 22, 2013, 06:43:37 am
content: Quote from: PA0PBZ on March 21, 2013, 09:58:12 pmThat is right, killed by a slight overvoltage when the 5V regulator went short and gave the full unregulated 14V to the whole unit. Overvoltage crowbar also failed to operate, dead thyristor on it. Irony is the chip is a SN5406PM3 high voltage open collector device.