K0HB:

Suppose the aliens are running their evil "Confabulator?"

How would a guy ever know then?

John

On Fri, 12 Aug 2005 20:13:09 +0000, KØHB wrote:


wrote


You don't need a noise generator, lab full of gear or an EE to know if
your receiver is sensitive enough. Just do this simple test:

1) Tune the rx to an unoccupied frequency, using the mode and bandwidth
you intend to use.

2) Turn off the AGC and turn up the gain until you hear the background
noise roaring away.

3) Disconnect the antenna.

If the noise drops way down, or disappears, you have all the
sensitivity you can use in that application.

You're joking, of course. You can't even get an approximate measure of your
receiver sensitivity/noise floor from that test. Suppose, for example, that an
active electrical storm is brewing and you're tuned to a 40M QRG. All but the
most stone-deaf receivers will give you some room-filling background noise which
will disappear when the antenna is removed.

Beep beep
73, de Hans, K0HB