If you don't have feedback on the intercom function, you have an RF feedback
problem. The shielded battery box says that 's what Lightspeed thinks too.
Transistors are a bunch of diodes that just love to rectify your RF. Since
you have a Europa, moving the antenna is not very attractive as suggestions
go. Try placing some .01 capacitors around the system to short out the RF.
If possible, in the battery box between the audio wires and the ground wire
and between + and - on the box terminals. Another good spot is on the
headset socket, do both if possible. As a test you could wrap a long strip
of aluminum foil around the headset wires and ground it to the earphone
socket with a short wire with alligator clips.
Hope this helps. RF shielding is really a black art.
Leo Corbalis
> > ----- Original Message -----
> > From: "Paul McAllister" <paul.mcallister@qia.net>
> > To: <europa-list@matronics.com>
> > Subject: Europa-List: Feedback problem with the radio
> |
> > | I have an odd problem with my GX60 when trying to transmit. I found
it
> > would start oscillating, it would start with an echo and then break
into
> > full audio feedback, similar to as what a PA system does when the
> microphone
> > is too close to the speaker. I fooled with the problem for the longest
> time
> > and I finally narrowed it down to my LightSpeed headsets. I called
> > LightSpeed and sure enough they knew about the problem. They invited me
to
> > send the headsets back and they would fit a new shielded battery box.
> They
> > came back and they "sorta" worked, but unfortunately they would still do
> it.
> > |
> > | A this point I resigned myself to using my Telex 3500's. These always
> > seemed to work, but today they started to exhibit the same problem...
now
> I
> > am in a bit of a quandary on how to trouble shoot this problem. I do
not
> > have an audio panel at this time, I am using the internal intercom in
the
> > GX60.
> > |
> > | Does anyone have any ideas where to head with this.
> > |
> > | Paul
> > |
> > |
> > |
> > |
> > |
> > |
> > |
> >
> >
>
>
|