The connectors on the Autocontrol II are part of the inductive tank circuit. The manual uses threatening language about changing their length, which is likely overblown, but at the very least they are impedance matched.
They have a very fine coiled center conductor (a filament) that is susceptible to breaking. The main Motorola-style connector to the artificial horizon had been originally built (or perhaps repaired) in a rather sketchy manner. The braid pigtails had cold joints, the crimp connector was not crimped onto the center insulator, and the fine wire conductor was subject to strain (wiggling) during installation. It broke, making intermittent contact, and making the system unreliable. Probably part of why it was originally taken out of service...
The following repair should make the fix permanent. It, at least, isn't breaking in that manner again, largely because of the immense amount of strain relief involved. Now the filament is not exposed to any strain at all, and even the 22 ga. lead is protected from additional strain, and has a loop to provide some freedom of movement if it does occur.
It is interesting that the technology used to attach this rather important and mission critical extension was the same as used to connect car radios. Mr. Piper knew a deal when he saw one back in 1960.
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| Fine wire is broken at center conductor tab and cold joint on pigtail |
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| Solder on an extension of 22 ga milspec (aircraft) wire |
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| Run the insulated wire back into the center insulator protecting the filament |
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| Apply some adhesive filled shrink tube for strain relief |
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| Cut the center conductor with a bit of a loop and solder to connector |
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| Reattach braid pigtail (sanded, fluxed, preheated) on this side and crimp down |
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| Completed connector - probably overdid the tape |
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