Headphone/microphone hearness for # 19

[Bob Carriere]

Found a "minute" wisker of copper that WAS formerly connected to the voice coil..... broken....and so small as to make it impossible to mend..... copper wire is finer than a human hair.

So there were no continuity acroass the two ear piece..... which explains why only one earphone worked.

Much like when I dissected frogs in class I could never put the frog together again.... so that earphone is Kaput!!

Now will turn my attention to a more complete NO 1 set with chamois covers..... it also only works on one earphone..... but will tread lightly and not do a full irreversible dissection.

Meanwhile I have opened up the control box and using the previous schematic I beleive that I can installattach a more modern earphone, so looking at installing a 1/4 male/female jack. This should allow me to test further the rec/trans. and see if it work properly.

I fear that most of the rubber bellshaped connectors have corroded contacts and the rubber is as hard and brittle has hard wood. They may look OK for a static display but for actual use very impractical. I know of no means to make the rubber soft again. Installing a jack or having a female jack hang out of the control box is relatively easy as the boxes already have two soft rubber plugs to pass the wired through.

Bob