[Lowfer] Strange 185300 signal

Sat, 25 Oct 2003 00:06:00 -0500

I wish I could post a lit light bulb right now. LOL!!! Glad my minor
suggestion sparked your mind into overdrive. Sometimes the simplest things
will get the ball rolling.

I transmit into dummy loads to get it down as well as insert resistance into
the VCC line until I get the signal buried low enough for ARGO for what I am
experimenting on. I guess that is why an Engineer can work well with a
Technician as together the well trained mind and the less trained mind come
up with better things than one does by themselves.

Now about that kit.........

You Da Man Bill...

Mike>WE0H

-----Original Message-----
From: [email protected] [mailto:[email protected]]
On Behalf Of Bill Ashlock
Sent: Friday, October 24, 2003 11:57 PM
To: [email protected]
Subject: RE: [Lowfer] Strange 185300 signal

>How about a receiver with no antenna connected and look at
>it in your house?

Mike, I think I just figured it out as I was reading your suggestion!
Disconnecting the antenna IS what I do to monitor my signal, but even with
the antenna disconnected, I still have to reduce the ARGO Sensitivity
adjustment to almost full off - and then there's no noise to simulate a
marginal receiving condition. What I just did was to reduce the transmitted
signal to about -60db by inserting a 10k pot in series with the Vcc running
to the final. Now I can set the Sensitivity to the normal amount and I can
see background noise that is close to the real-life amount. Thanks!

By thinking about this I also just now came up with the reason why a 1 to 2
db signal level cannot be seen, on average, with QRSS - even though I can
indeed prove the opposite right at this minute. Because the received signal
is randomly varying at least 2 db in a skywave situation, there is no
defined threshold in which to detect a small signal level change. If the
signal were constant, as it is in my setup with ARGO looking at WA, right
now, I can show that there IS a sharp threshold, and 1 db makes a lot of
difference.

I also came up with an idea to simulate a randomly varying signal. There's a
random number generator in BASIC and I can use this to apply a 2 bit (4
level) power level control to the transmitted signal and view the results
right here. Thanks again!

Bill A

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