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Information on Racal 9065A RF attenuator?
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EC8010:
Today at an amateur radio rally, £15 bought me a Racal 9065A 1U rackmount RF attenuator. Input and output are on N connectors, three decade front panel knobs go from 0 to 200dB in 1dB steps, and taking the lid off suggests a pair of 0 - 100dB attenuators controlled by an alarming 5" x 6" logic board having 50 (!) discrete transistors and some pre-74 series logic. I'm guessing it's to convert the denary code from the three front panel rotary switches into appropriate relay controls for individual attenuators. Mains comes in on a fairly lethal connector and the safety earth bond to chassis is the worst I've ever seen.

It will clearly need a certain amount of remedial work, so any information that would help justify the time (or help fix faults) would be much appreciated.

PS. I did search...
EC8010:
Well, I was impatient. So I made a mains lead, fixed the earth bond (1.3 ohms and variable) and PAT tested.

And it LIVES! I am astonished. I squirted 1kHz square waves through it from a function generator, terminated it properly and saw all the attenuations I expected between 0dB and 80dB. More importantly, I didn't see any low frequency noise/spikes on the square waves or variable leading edge shape (did with an aged R&S purely passive attenuator). Despite what the single reference on the Internet says, it does not go to 200dB. Maximum attenuation is 130dB. I'm guessing that it should be good to 1GHz given the N connectors. No doubt a pair of N to BNC adaptors will each cost as much as the attenuator. But I'll still be happy.  :)
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