>> Hi Gang,
>>
>> I was wondering what the pundits do to look at transmitter output with
>> their scopes. Obviously, one doesn't put the output of even a 5W rig
>> directly into the scope input, let alone trying that with a 100watt rig.
>> Right?
>Connect Rig to 50 ohm dummy load and connect low C scope probe to output of
>rig. P=ExE/R so with 100 watts output voltage across 50 ohm load is 70.7
>Volts, well within the scope's rating. A good rule of thumb to remember is
>that 50V across 50 ohms is 50 watts.
I'm quoting out of a digest so please excuse any misquotes. The only
time I have ever wacked a scope was a Tek 465 when a transformer shorted
on a servo amp out of a radar. I shoved 3500+ volts down the scope when
I was expecting 300 or so. The attenuater pad popped on one setting.
The nifty super expensive HP digial VOM just blanked its display. The
reason that I know that I was 3500+ is that was the rating on the VOM
(to 100 MHz!).
You should be able to measure just about any transmitter output into
a 50 ohm load with any reasonable scope.
Dave
KB2YWT - ex 22L20 Nike Test Equipment Repairman
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