Thread: Noise Threshold
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Old 22-Jan-2016, 8:08 PM   #5
Retired A/V Tech
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,565
Thanks for the Net NM Calculator.

I had trouble downloading it and using it because its file had a php extension, but it was listed as an xls file in the attachment name. The solution was to change the file extension to xls, and it worked well for me.

I used line 7 for the balun loss.

One minor criticism; line 15 says Net NF. I think it would more correct to call it Net NM. Andy Lee calls it Net Residual Noise Margin.

Here is the System Noise Figure calculation.

I used the System Noise Figure calculator by holl_ands and majortom.
Attached Images
File Type: png NetNMforDX.PNG (36.2 KB, 5164 views)
File Type: png SysNFDX.PNG (34.0 KB, 5130 views)
File Type: png NMdiagDX.PNG (51.0 KB, 7444 views)
If you can not measure it, you can not improve it.
Lord Kelvin, 1883

Last edited by rabbit73; 11-Sep-2017 at 9:26 PM.
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