BB66C Input Impedance

According to specifications, the BB66C should have an input impedance of 50 ohms.
Using a 50 ohm output signal generator (Agilent 33220A), an output frequency of 10KHz is selected with an output level of -20dBm.
The signal generator is TEED with an oscilloscope (high input Z) and the BB66C.
If the BB66C has an input Z of 50 ohms, the scope should read a -20dB level, but it does not.
Using just an ohmmeter, the input R of the BB66C is >1M ohm with or without power.
Using the same above test procedures with the USB-SA44B, all is normal (as expected).
I just want to verify that the BB66C does or does not have an input Z of 50 ohms?

Hello Roger,

Thank you for calling in. Hopefully we were able to fully answer your questions. If you need anything further please let us know.

Regards,
A.J.

For anyone else that is curious, The BB60C has a 50Ω input impedance and AC input coupling so it won’t look like 50Ω using a multimeter but at RF frequencies it is 50Ω. The SA44B has a DC coupled input so it will look like 50Ω to a multimeter.

Bruce

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