Crawls Backward (When Alarmed)

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I'm Astatic

A quick diversion from the Surfcaster. A buddy from work plays sax in a working band. He brought me his late 40s Astatic model 77A microphone to take a look at. It was on and off the bench so fast I didn't take pictures while it was apart, but here are some 'after' shots.

This is a low-impedance dynamic mic. The intended use was PA and amateur radio. These things are really the bees knees. Astatic is still in business and still makes PA gear, but nothing as cool as this.

The best known Astatic mic is the D-104, which is extremely popular with amateur radio operators (aka 'hams').

My buddy wanted an XLR connector put on the cable. It came to me with the vintage Amphenol MC3M 3-pin connector on one end to connect to the mic, and a 1/4" phone jack on the other. It didn't work at all. I wound up opening up the mic where I found the wiring had been re-jiggered pretty sloppily. I resoldered it, and sussed out the leads for the shield and the two signal leads. Then I opened up the MC3M and discovered only ONE signal lead was connected! No wonder it didn't work. Rewired and soldered those up and put the XLR on the other end.

Tested it into my rebuilt Champ 600/5F1 (that post is coming here too...) and it sounds amazing! I put the impedance switch (see the pic) on "M" (middle? medium? meat?) and that was the best match for my amp.

He's overjoyed with the mic and is going to use it on a gig tomorrow. Should be a real conversation piece. As with a lot of old gear, it's built like a tank and with a little service, will keep running for another 40 years.


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