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Electronics => Projects, Designs, and Technical Stuff => Topic started by: oz2cpu on April 21, 2022, 09:24:06 am

Title: HP 8690B sweep generator, why 2kV regulated supply, teardown video links
Post by: oz2cpu on April 21, 2022, 09:24:06 am

i just made a deep teardown of an HP 8690B sweep generator
the main unit is Tube-Transistor based hybrid
a thing that i found very special is the regulated 2kV supply made by two large pentodes
really ??
no other way existed at the time ? to make this product work ? but to use VERY high voltages ??
the resulting voltage control sweep signals used by the rf plug in, is very low.. so that is why i found this very off, and very complex.
feel free to post comments here, or on the video

part 1
https://youtu.be/IhKC49kEaXg

part 2
https://youtu.be/WrdIDoIJBvk

part 3 (plug in module 0-110MHz)
https://youtu.be/c_Z2QxXNruA

Title: Re: HP 8690B sweep generator, why 2kV regulated supply, teardown video links
Post by: woodchips on April 21, 2022, 06:42:17 pm

Didn't they use backward wave oscillators to start?

Not nice to work on.