Please Help with the Identification of this Part

There is no image in your posting so not possible to even know what you are referring to.

Hi Dave,

I will try again to post it here.

John

A nice 1982 vintage part. It does look like a resistor array but how it's configured is unknown.  If you measured side to side, what do you get or maybe Pin 1 to any of the others? The 1 to 12 indicates some kind of SIL type array but in a DIL package.

I suspect the marking on the top is a reference to a production number or version.

There are only 8 pins yet the numbers go from 1-9 so it makes no sense.

I don't suppose you've tried removing the paint or whatever coating it is?

Nice mystery though.

Mark

Mark, it is the production month or something similar. It does not go up to 9 but (next row) up to 12 (months). The black pin on the 10 means (suppose) it is the production lot of October.

Instead I think that HAMLIN 82xx is the model. Maybe a Reed relais array ?

Enrico

If you have 100 then I think one can be sacrificed to some destructive investigation.

Thank You,  Fred27 balearicdynamics  mcb1  DaveMcLaughlin ,

I have taken your advice and I have sacrificed a couple of the components to discover their mystery ID. Once the veneer was removed I could see that it was laid out as a resistor array.

Pin 16 comes in as a metal trace that runs down the center of the chips. Laid over the top are black resistive material to each of the remaining 15 pins. Except for the resistive material to pins 10 and 12 the material has been cut with a ? laser on all the other pins. The apparent intent here was not to produce good quality resistors or good quality cuts.. Here is a close up of the chip at the right.

If you look closely you will see that only Pins 10 and 12 do not show the cut extending across the material. Further the cuts that are across the material of the other pins are poorly done. Actual resistance can range from 200K all the way to OL and none of the readings are stable except the reading on Pins 10 and 12. When I tried to read these unstable resistances with the megger they all showed low resistance at 100 V. None of the resistances, even those on Pins 10 and 12 are consistent from chip to chip. Here is a chart that I made of 3 random chips to show the resistances between the common pin 16 and each of the other pins. The ohm readings are in black.

Sorry it isn't a little clearer but you can click on it to enlarge it. Note that the common to pin resistance in black is not consistent between chips including the pin 10 and 12 readings. My conclusion at this point was that the actual resistances do not matter as long as there is a large difference between the cut traces and the not cut traces. These chips are a form of cheap factory programmable DIP Shunt. I set up a test circuit where I tied the common of the three chips to ground and then I put a 10K pullup resistor between a 5 volt power supply and my meter DC voltage probe. I then probed each pin on each chip and took the readings and wrote them in red on the chart. All Pins read High (close to 5 volts) except the Pins 10 and 12 on each chip which read 0.06 Volts.

Perhaps a manufacturer determined that it would be cheaper to order programming shunts in this manner as opposed to using more expensive switches or more labor intensive punch out shunts. The answer is probably lost in the past.

Thank you to those who responded and gave me the help to pursue this to a more understandable conclusion.

John

Perhaps the links were opened with series of high-current pulses.

By the looks I think they have been trimmed to be some particular value. The fact they seem to be different makes me wonder if they are just releative to each other or  some such ..hey I'm just guessing!! ;-)

Hi Jon,

I reckon you're right or extremely close. Because the numbers on the top must be something that people could scratch off, or cover perhaps. They only go to 12 although there are 15 resistors, but since three of the numbers are underneath 1,2 and 3, maybe there was some convention for indicating the higher numbers, or the extra ones were some sort of parity check?