03-03-2017, 12:02 PM
We did get very close back at post #81.
We got a bit of a distraction from the Russian transistor sellers and it has taken us a little time to get back to it again.
I tried to recreate the collector currant and HFE curves for some transistors out of those bags of cheap bits that were on sale in the 1970s.
I basically built a small part of a curve tracer that required 25 measurements to get a low def display on a bit of graph paper.
In those days electronic calculators were expensive and in most places were worshiped and guarded. Pens used to run out fast.
I still have the gadget I built at the time and it still works.
I could offer to do a full service on it and ultimately add an internal DVM to replace the external meter it was originally made for use with.
It is still used to test large audio transistors for matching. and selection.
We got a bit of a distraction from the Russian transistor sellers and it has taken us a little time to get back to it again.
I tried to recreate the collector currant and HFE curves for some transistors out of those bags of cheap bits that were on sale in the 1970s.
I basically built a small part of a curve tracer that required 25 measurements to get a low def display on a bit of graph paper.
In those days electronic calculators were expensive and in most places were worshiped and guarded. Pens used to run out fast.
I still have the gadget I built at the time and it still works.
I could offer to do a full service on it and ultimately add an internal DVM to replace the external meter it was originally made for use with.
It is still used to test large audio transistors for matching. and selection.
