Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!utgpu!water!watmath!onfcanim!dave From: dave@onfcanim.UUCP Newsgroups: sci.electronics,rec.aviation Subject: Re: headphone jacks for microphone input to aviation radios Message-ID: <15479@onfcanim.UUCP> Date: Sun, 22-Nov-87 12:15:50 EST Article-I.D.: onfcanim.15479 Posted: Sun Nov 22 12:15:50 1987 Date-Received: Wed, 25-Nov-87 01:31:58 EST References: <532@zehntel.UUCP> Reply-To: dave@onfcanim.UUCP (Dave Martindale) Organization: National Film Board / Office national du film, Montreal Lines: 34 Xref: utgpu sci.electronics:1566 rec.aviation:4363 No, you can't buy *aviation* mike plugs and jacks at Radio Shack, at least not any Radio Shack I've seen. Standard phone plugs/jacks, regardless of the number of conductors, are intended for plugs with a nominal diameter of .25 inches. Aviation mike plugs are .206 diameter, with the jacks being .210. The relevant Switchcraft part numbers are: S-260 3-conductor plug; standard quality (like you see on Telex headsets) S-230 right-angle 3-conductor plug; otherwise similar to S-260 480 3-conductor military-type plug (military designation PJ-068). This one is several times the price of the S-260, but its body and contacts are machined out of solid brass - this is what David Clark headsets use. S-12B panel-mount 3-conductor jack S-13B same as above, but with additonal contact that connects to the "tip" circuit when a plug is not present. C-12B military version of S-12B; the only difference listed in my catalog is that C-12B has an indexing pin to prevent rotation in the panel S-830 in-line 3-conductor jack (as you would use in an extension cable) Note that the S-260 and 480 jacks differ in the diameter of the "ring" contact - it is the same diameter as the barrel in the S-260 but smaller in the 480. You have to make sure that the mating contact in the jack is bent in sufficiently to make proper contact with the recessed ring of a 480. Otherwise, you'll have a jack that works properly with a Telex headset but poorly or not at all with a David Clark. In Canada, the only place I've found that carries them is Electro Sonic in Toronto. Of course, you local avionics shop will likely also have some.