Drop on high pass filter measure
If your oscilloscope was at the 1MOhm input state (1:1), then the input impedance would form a 1MOhm load to the 200kOhm. 

If you switch your scope to 1:10, then its input impedance will go to 10MOhm!

Also, the bandwidth of the probe will improve noticeably when using the 1:10 position.

Corollary: Always use the probe at 1:10, unless the signal is really too weak.