It is important to distinguish between the two types of connector "loss":
1. Dissipation loss, which would cause connector heating.
2. So called mismatch "loss" IE reflected power.
For #1, I would suggest running 1,500W through the connector in question
for a while and seeing if there is any significant heating.
For #2, terminate the cable with connectors in an ACCURATE 50 ohm
termination and measure the VSWR with a calibrated VNA.
Below 200 MHz, I would venture to say that loss of either type should be
virtually unmeasurable. The tests above are more of the "sanity check"
type to detect improperly installed connectors, or offshore connectors
that are complete junk, or connectors that got water inside. Even if
some mismatch is detected (like 1.1 to 1) it likely doesn't matter for
ham radio.
Rick N6RK
On 8/23/2025 12:19 PM, Jim Brown wrote:
On 8/23/2025 11:08 AM, john@kk9a.com wrote:
I mostly agree. Connector loss is minimal.
Yes. About 15 years ago, I made up a lot of cables for a DXpedition,
with soldered 83-1SP on 100 ft lengths of Commscope 3227, an RG8-size
cable with a solid #10 copper center and foil/tinned copper braid that
is superior to LMR400. For final test, I spliced all 13 of these cables
together and measured loss by substitution using HP generator and
spectrum analyzer. That's 12 barrels and 26 83-1SPs.
Loss at 200 MHz (as high as I went) was slightly less than the mfr's
spec for the cable.
73, Jim K9YC
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