Here's a really simple sampler/signal pick off device.
1 - Use a UHF TEE connector. Shown below.
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Female >---------------< Female
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Male
2 - Remove the center male pin by unscrewing it from the connector.
Not all center pins will be able to be removed by simply unscrewing
the center pin. Find one that will. The remaining female to female
center pin will be floating free in the connector dielectric.
3 - Use a UHF Female to Female barrel connector, and screw it into
the Male port you just removed the center pin from.
4 - Connect your amplifier or rig output to one of the Female ports and
the other Female port to a dummy load.
5 - Connect the "Tap Point"(the Male port on the Tee which now has a
Female barrel screwed into it) to your measuring device(ie: scope).
6 - As measured on an HP8753C VNA, the tap port is better than 90 dB down
from the main line at 28 MHz with a 50 dummy load connected to the
thru line.
7 - The stray coupling capacitance between the main line and the center pin
on the inserted female to female barrel provides a capacitive pick off
point for connection to a measuring instrument. The signal is not
calibrated relative tot he main line but can be used for monitoring
at reduced mainline amplitudes.
Karin K3UU
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