What are these boards from? Who can make use of them? - Page 1
Forum section: electronics / general

author: 1audio
author_rank: Frequent Contributor
timestamp: November 26, 2018, 01:19:57 am
content: In cleaning a pile of stuff in my shop I saw these boards I had picked up at some swap meet or???They are out of some IET instrument. Probably an earlier version of a resistance standard. I really don't have use (I have a JRL and an ESI resistance standard box) but they should not go into e-waste, especially with all those relays.

author: Vgkid
author_rank: Super Contributor
timestamp: November 26, 2018, 01:32:24 am
content: Who made the resistors , they look interesting.

author: 1audio
author_rank: Frequent Contributor
timestamp: November 27, 2018, 03:34:43 am
content: They are large and seem to be wirewound. There are no mfr. markings just some numbers and a value. The whole PCB is conformally coated so its not easy to connect to the resistors. The inductors are all marked Dale. The resistors are in a binary sequence 1,2,4,8 to 128 it seems.if you have the instrument and need one of these boards I'm sure IET would get a bundle for them. I have realized they aren't a lot of use for me.

author: cdev
author_rank: Super Contributor
timestamp: December 08, 2018, 05:54:16 pm
content: Are all the yellow boxes relays?

author: alm
author_rank: Super Contributor
timestamp: December 08, 2018, 08:20:04 pm
content: Looks like a bunch of inductors / resistors switched by relays to me. Given the binary sequence, likely a variable resistor / inductor, which might be part of an automated bridge. GenRad (and by extension IET) made quite a few of those. This is just speculation; I've never seen the insides of such a bridge.

author: Edwin G. Pettis
author_rank: Frequent Contributor
timestamp: December 09, 2018, 07:07:21 pm
content: Sorry, the resolution is insufficient to 'read' any part numbers, can you do a zoom in on some of them or just write the numbers down. Even the board numbers are a bit difficult to make out. Without more information I can't make any identifications.

author: umkumiut
author_rank: Contributor
timestamp: December 10, 2018, 10:57:14 am
content: Quote from: cdev on December 08, 2018, 05:54:16 pmThey look like Aromat (Panasonic) ones.

author: 1audio
author_rank: Frequent Contributor
timestamp: December 14, 2018, 06:02:16 am
content: A few more details.The boards are conformally coated and the connectors are eurocard-esque but use hollow sockets, 200 ea, and must be really expensive.Boards have part numbers and serial numbers Common is a serial number starting with 85350XXX Pt. No. 002(6404120 1) or similar.!) Aromat DS2E-ML2-DC24V relays2) Resistor markings. They all look like wirewound but I can be fooled . Marked for example:141938521 CNRWR78S3201FR3) Inductors are Dale marked TE4 or TE5If someone can make use of these please contact me.

author: Edwin G. Pettis
author_rank: Frequent Contributor
timestamp: December 14, 2018, 06:03:07 pm
content: The resistor is a MIL-PRF-39007 style RWR78, date code is 8521 CN, the part number 14193 is a house number, these are power resistors, not precision. They are 1% and come in a variety of TCRs, may have been made by Dale as well. You can find general data sheets on the RWR78 on line, they have commercial versions as well.