I was playing with some headphones today. I have an old and cheap pair
of Lafayette 8 ohm 'phones as well as a nice but bit set of 20 ohm Telex
phones. All of my radios including the Scout will deliver a watt or two
into a low Z load, so with these headphones the radios are capable of
blowing my brains out.
The simplest fix is to add a 220 or 330 ohm resistor in series with the
headphones. If the phone plug shell unscrews, add the resistor inside.
If it is molded on, cut it off and install a ne w plug or make an
adapter. The adapter can be made using a phone plug and inline jack. If
you can't find the inline phone jacks, use a panel mount jack installed
in a 35 mm film container.
The resistor knocks down the signal to a comfortable level and improves
the signal to processor noise level in the Scout, and it will help save
your hearing if you accidentally turn the volume up too high.
220 and 330 ohm resistors worked for me, but select what's comfortable.
This is best done by setting the cw sidetone to a comfortable level with
the speaker and the try different series resistors to get the same
comfortable level in the headphones.
Of course, older phones like my trusty (and painful) Trimm magnetic
phones (used only when I'm feeling nostalgic) or the more modern surplus
phones like the Telephonics types, don't need the resistor fix.
WARNING: Don't iron clothes while wearing them and don't wear headphones
while driving.
73,
Bob WB2VUF
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