On 2 feb, 00:00, Neil wrote:
i have a 80 foot longwire, attached to the center conductor of a coax
which then leads into my house and to my reveiver (NRD 545). The coax
shield is grounded at the entry point into my house..

I have no balun between the longwire and my coax. So my question is
would a 9:1 balun give me any SIGNIFICANT improvement in signal level
or in noise reduction?

Hello,

On the longer wavelength ( 150m), where the total impedance of the
wire is far above 50 Ohms (absolute value), you will get more signal.
It does not guarantee better S/N ratio as external noise may increase
as much as the signal.

I believe, but not tested it, that on the shorter wavelength signal
can both go up or down, as at several frequencies the wire itself will
be closer to 50 Ohms. For reducing noise, you may experiment with
changing the ground connection (if strong interference is generated in
your house and gets into your antenna via the ground connection).

Best regards,

Wim
PA3DJS
www.tetech.nl