Posted on Feb 4, 2014

A friend and frequent event-production collaborator has been accumulating legacy Telex wireless intercom gear from various sources, and while the equipment arrives in a nominally working state it sometimes has a few little problems and tends to take a certain amount of wear and tear on gigs anyway. With enough annoying problems having built up ove

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r time across his pile of gear, he asked me to take a look at a bunch of it to see what could be fixed/improved/whatever. Some of it was pretty minor - broken XLR connector latches but he had spare parts for that; miscellaneous loose stuff; and a lot of dirty/corroded battery-pack contacts which 90+% of the time are behind flakey performance. [You`ll see my spraycan of de-ox-it in several of the pictures. ] The intercom-connectivity is easy to get wrong with mis-setting of a nine position DIP switch and a level selector, needed to adapt to any of *four* common wired-side standards. But some of the issues were more subtle, such as distorted audio or units that used to work together and since failed; these would require a little more investigation. One easy thing to miss when systems are set up is the fact that there can be either dynamic or electret microphone elements in the headsets, and the little slide switch in beltpacks or base stations needs to be set to match which type is plugged in. The headsets show absolutely NO external indication as to which is installed. Mismatches generally result in very low transmitted audio. The operation manual for the Radiocom TR-200 belt-pack transceiver specifically states "all headsets used with this intercom are dynamic microphones", which is clearly wrong since the small collection provided to me for testing turned out to be a mix of both types. Fortunately, it`s easy to test for...

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