I am happy to report that I did personally enjoyed 90s too
I was twenty years old and even analog electronic components among RF tubes they was looking as magic.
Today First December 2019, I was researching Oscilloscope Curve Tracer circuits and found the SOURCE of the oldest 50Hz EUROPEAN Curve Tracer and this is no other than the German HAMEG.
HAMEG in this decade it is taken over by Rohde & Schwarz , but this is another story.
HAMEG HZ56This is a product born in Western-Germany (date unknown) then it was refreshed two times, second revision marked as HZ56-2 and latest revision was HZ56-3.
From the first version of HAMEG HZ56 up to the latest only the shape of pilot-light changed and the printing on the box, because HAMEG become German brand after the unification with East Germany.
Product design it is tremendously simple,
so simple that Kids stolen it and name it as
octopus curve tracer.
Most octopus schematics that I came across they are filled with design errors and poor additions.
I even found a comment that
octopus curve tracer it is electronic design with roots at 60's , but I was not able to confirm it.
The standard design this using a small transformer among with Sense Current resistor among with one limiting current resistor.
R1 & R2 values. They are 10 Ω for R1 (Sense Current) and 1 kΩ for R2.
The switches for transistor testing they simply select the testing pair (nothing special to it either).
I did manage to collect few pictures of the European (discontinued) Oscilloscope Curve Tracer for safe keeping for as long the ITTSB Blog this is alive.
And the PDF file of the latest
HZ56-3