LOTS of truth here. There are two applications notes on my website, two
about stubs for harmonic suppression (one is text, the other a Power
Point), another about bonding, that are also required reading. The one
about bonding was the jumping off point for Ward's book, and the one
about stubs offers important insights that George missed.
http://k9yc.com/LocatingStubs.pdf
http://k9yc.com/StubPlacement.pdf
http://k9yc.com/GroundingAndAudio.pdf
Another issue that W3LPL reminded us of is Passive Intermod which can be
both inside and outside our stations. One common place it occurs is at
the junction of the boom and mast via the rotator, and is solved by
bonding around the rotator. It also happens in electronics of all
sorts, most notably switch-mode power supplies. If the harmonics/spurs
you hear are "growley" sounding, it's probably passive intermod.
73, Jim K9YC
On 3/21/2018 7:15 PM, Tim Duffy wrote:
As AC0C points out - making multiple stations work is not easy. Bonding is
important (much more than most station owners realize) and using high
performance filters and quality interconnect cables (with good quality
properly installed connectors) is mandatory. Connectors MUST be tight. The
recent N0AX book on grounding and bonding is a good read on this subject.
What was a state of the art station design 20 years ago will not cut it with
the high performance SDR RX platforms of today. The epic W2VJN book is a
MUST read for anyone wanting to make SO2R or multiple stations at a single
QTH work properly.
Bottom line - there is no free lunch.
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