lagasse@biomed.UUCP (Robert C. Lagasse) (09/13/85)
In a previous article, Paul Kube asks about using a 5 Ohm microphone with modern systems which are at a much higher impedence. The answer that I can provide is probably not useful, but.... It might be easier to find a new microphone element that is of an impedence that matches your radio set if the old one can be surgically removed neatly , and the new one of a (hopefully ) smaller physical size implanted. A new element is bound to be smaller than the one in a vintage headset. Matching impedences through a transformer will introduces some losses which may not be tolerable without additional amplification. A small audio transformer with one of the windings at a 5 ohm impedence is an animal I have never seen in any of my many catalogs. If you could find one, additional amplification is no big deal and could be added to the headset at the earphone area and potted in place witha resin, or it could be added to the guts of your radio set. You might want to post your original question in net.analog which will no doubt unearth the audio gurus.