"Ralph Mowery" wrote in message
...

"Dave" wrote in message
...

Hey Ralph, thanks for coming in. I am wondering though if I can't tune
out some of the noise,and eliminate more with a directional antenna
(which I currently don't have.) Would an IF stage not help me here? Or
a second tuning function, on the output? Just wondering.

Do appreciate your comments. If I'm wrong I'm wrong, I was just thinking
these things might help. No? The signal I am trying to clean up is at
9335 kHz.


Dave you started with a simple whip 40 some inches long. As I mentioned ,
no mater how much amplification you have , the local and not so local
noise will limit the ammount of amplification you can use. All you will
amplify is noise. Lets say you have a noise floor of .3 microvolts and a
signal is picked up from the antenna of .4 microvolts. Your signal will
be higher than the noise and you can hear it to some extent. If the noise
is .5 microvolts and you get the same signal , then you will not hear the
signal. If you add an amplifier (one that has no noise of its own , which
is impossiable bu the way) you may get .8 uv of signal, but you will then
have 1.0 uv of noise and you will still not hear the signal. The amp may
add .1 uv of noise so you then get 1.1 uv of noise and only .8 uv of
signal.

You may change the antenna to a tuned loop. Take a couple of sticks about
3 feet long and make an X out of them and wrap a few turns of wire around
the outside of the X so you have a loop about 3 feet square and tune it
with a capacitor to the frequency you wish to hear and it will be somewhat
directional. That may help.

The main thing is that a 3 foot whip in the house is not going to be a
very good antenna for shortwave.



Huuuuhhhh. Okay, I think I am beginning to understand. At least, when you
put it in those terms.

I had thought about using a loop, but for some reason decided to try the
whip first. I guess 'cause that's what I had handy, and I wasn't sure how I
would mount a loop. Until I can figure that out, I am going to try tuning
the output of the RF amplifier the same way I tune the input. If I can work
out the last detail of doing that.

Your words, and numbers, are much appreciated. And your patience.

Thanks, Ralph.

Dave