lostinlodos wrote:
This stuff varies considerably and judging from photos is difficult.
Generally speaking you’re looking at midgrade or peripheral for most boards like this.
It depends on the amount of flashing and trace, and what the trace material is.
These Olson often have copper sheets in between the polymer board layers. Though rarely solid sheets; usually strips where large amounts of through hole connections are made.
Silver trace copper boards normally get peripheral.
Unfortunately boards like this the ONLY way to class them is to hand it to someone for a quote. Eg, send them in.
I have a lot of these too from tearing apart vintage testing equipment. Your info helps a lot.