The circuit has the traditional configuration that can be found elsewhere on this site. This is from 80s documentation and the LM350 can be used for higher current.
In fact, we can say that this circuit found in documentation from the 90s, consists of an intercom...
The basic integrated circuits of this 1988 multimeter are no longer very common today, but if...
This circuit is from an old publication of the 70's. It can be implemented with modern transistors like the...