On Mon, 03 Oct 2005 02:05:29 -0400, SR wrote:

I notice something interesting about this radio. Their are terminal for
6 meters. Throughout the last 10 years when I had scanned the 6 meters
on my scanner, I do not think I had never picked up any hams. (BTW I am
in the New York City area) Yes it is a very short band and it might be
more related to 2 meters, I would think.

So why would Hammarlund go through the effort to add terminals on the
rear of this radio. My only guess is that at the time hams were using
the 6 meters a lot more.

Also, this radio does not seem to pick up much on the 21-21.6 and 28-30
bands.

I have a reprint copy of the manual. I was reading the part of the SEND
RECEIVE CAL button. And somehow this has something to do with something
called BREAK-IN RELAY. (There is a relay female chassis connector at
the rear.)

Because of this can this radio make some kind of transmission?

Could someone please explain this to me in layman terms.

Most likely the CAl position turns on small quartz crystal osciallator
with a 100Khz crystal. It generates harmonics at 100Khz intervals, and
isued to calibrate the dial on the radio. Turn it on, set the receiver
to CW, and zero beat the calibrator signal, adjust the tuning dial
accordingly. It makes the dial readout more accurate.

You don't want it on all the time, because it will wipe out any signal
you reall want to hear that is close to a multiple of 100Khz.

Many receivers have a provision to put them into standby by remote
control. The remote control was often provided by a relay.
In a PTT or VOX operationg, the transmitter would provide a signal to
either activate a relay, or command the receiver into standby when the
transmitter came on, and take it out of standby, back into receive
when the transmitter went off. This was frequently called break-in
operation, and is much easier and faster than turning the receiver to
standby, turning on the transmitter (even with PTT), turning off the
transmitter and turning the receiver back on.

.. Even with a T/R switch in place, it would be rare to be able to
provide enough isolation to prevent the receiver from 'hearing" the
transmitter, hence the need to take the receiver effectively offline
in standby..

'Send' just puts the receiver in standby usually