HP 33321SB aka 33321-60026 Attenuator: HP 8662A Synthesized Signal Generator fix

Finally, I received the attenuator set for the HP 8662A repair. The very special 5+40+40 db attenuator with a side connector (rather than the usual design of these attenuators with two top SMA connectors).
However, a quick test showed that the 5 dB step is not working right. The “through” path is fine, but when I engage the 5 dB attenuator, is is something like 45 dB, unstable. Maybe a blown segment? That would be an easy fix.

So, I opened it up carefully, and found a broken contact. It seems the side connection is pushing a bit on the contact, and over the year, this design caused the plastic to fail. Tough to fix without precision drills and machine tools. So it will need to wait for the virus to clear, and for me to go to the German workshop again, to attempt an repair.

There are two small plastic studs, and they broke off, maybe the plastic got brittle over time with the pressure of the side contact pushing.
Let’s think about how to fix it, if at all possible.

Note – the seller was kind enough to refund half of the price, without having me to ship back the part, fair enough. At least some spare coils and segments should I need to fix other attenuators in the future.

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