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USB to Serial Port problems--Prolific Drivers Aug 3rd 2012, 18:27 2 3,118 on 26/12/15
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Latest Posts

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QST archives or not KG5OOU 5 days, 8 hours ago
Understanding SWR ralphm 1 week, 1 day ago
Our original archive allows the download of older articles.

Zack W1VT
ARRL Senior Lab Engineer
how can you measure the rx noise floor at your qth KK4BHS 2 weeks ago
In theory, it is just a matter of looking at a panadapter display that goes down to -130 dBm or so with a 2 kHz bandwidth. In theory, the thermal noise limit is -174 dB/Hz so with a 2kHz bandwidth the maximum sensitivity of a receiver with that bandwidth is -140 dBm. Most people are very good at picking out various signals and ignoring them when making an estimate of the noise floor--it may be a little tougher to program an automatic system to make that distinction. It is very easy to introduce common mode noise generated in the ham shack while making his measurement. Tom, W8JI has some suggestions on this web page.

Zack Lau W1VT
ARRL Senior Lab Engineer
QST archives or not KG5OOU 2 weeks ago
Login to
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Zack Lau
ARRL Senior Lab Engineer
fldigi WF button bug W3HBM 3 weeks, 3 days ago

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