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Dave Platt[_2_] Dave Platt[_2_] is offline
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Default Antenna longer for C. Crane Witness how?

In article ,
inter naughtfull wrote:
Hi,

I have a C. Crane Witness radio. It came with a short wire FM antenna
that plugs into the headphone jack. It doesn't receive that well, and I
was wondering how to get a longer one. I've looked online and can't
find one. The antenna has a little
half length mini plug that doesn't cut the speakers out when you plug it in.
I want to use this radio because it has a record feature.

I was considering cutting off the end of the original antenna and splicing
on another wire. I'm not sure what type of wire to use though.
Can I use an old pair of ear bud wires? Does it have to be a special
type of wire for an antenna?


No, nothing special is required. You'll probably want to use a
stranded-conductor wire rather than solid-conductor, so that it's
flexible, but aside from that there's not much to say. Earbud wire
would probably work, but this is often of a "tinsel" construction
which is difficult to solder successfully. You can try using just a
length of ordinary low-voltage "hookup" wire (22 or 24 gauge, PVC
insulated).

I suspect that the FM section in this sort of multi-function MP3
player is rather an afterthought... probably a single-chip AM/FM
receiver. These are generally useful for listening to strong local
stations under good-signal conditions, but aren't really designed for
weak-signal ("DXing") use.

A radio which is intended for serious FM listening is going to have a
dedicated antenna input jack, usually with either a 75-ohm or 300-ohm
impedance, which you can hook up to an antenna of the proper
impedance... this helps provide good matching of the radio-frequency
energy into the tuner front-end circuit. Table and portable radios
usually don't have this, and the signal coupling from wire antenna to
tuner circuitry is often rather hit-or-miss. As a result the radio
doesn't get as much (or as clean) a signal as it might.