This installment will complete the compensation adjustments on the CA plug-in.
Here's an internal view of the CA plug-in. The compensation variable capacitors are all neatly arranged on the far right in a row. Channel A top, channel B bottom.
![](https://imagizer.imageshack.com/v2/xq90/921/K1UMme.jpg)
The test set up. Heath IG-4244 Scope Calibrator set to fast rise time 1Khz square wave and the Fluke 1900A Frequency Counter connected to the 535A Vertical Signal Out as a monitor.
![](https://imagizer.imageshack.com/v2/xq90/922/TTfYwV.jpg)
Of all the attenuators the only one was slightly off. Channel A, 0.5V/div.
![](https://imagizer.imageshack.com/v2/xq90/921/OtsYzJ.jpg)
Fixed.
![](https://imagizer.imageshack.com/v2/xq90/924/iONyGN.jpg)
Now the IG-4244 set to 1MHz.
![](https://imagizer.imageshack.com/v2/xq90/922/m2DbXF.jpg)
Amazingly good 1MHz waveform. The bandpass of the CA plug-in is 27MHz while the 535A is only 15MHz. So the 535A sets the total system response.
![](https://imagizer.imageshack.com/v2/xq90/924/hCTFrE.jpg)
Next up......a more involved frequency response check.