Hints and Tips
 

Hi all,
I'd like to see a thread on hints and tips you have picked up or devised
while developing circuits.
I'll give you one to start;
While involved in the development of a couple of class E amplifier products
the collector voltages peaked at over 600 volts The scope was only capable
of
displaying 400 volts. I put an attenuator together that made the probe a X20
probe,
while still keeping the HF response.
Parts used;
BNC T
BNC to F connector adapter
F connector
920k Resistor
100 pf capacitor
Heat shrink
Brass shim stock to make a cover
I'm sure other parts could be used, these are what I had available.
See the attached drawing for more details.
The resistor and capacitor values may need some adjustment for you probe.
I used the internal calibrator and adjusted R and C values until I had a
sharp
square wave and the proper voltage reading
I made a shield from brass that corrected some ringing (ISTR).
I do recall the shield was important.
Be sure to insulated the lead that passes through the F connector.

Yes, I know the probe cable has a limit to the voltage before it arcs.
Yes, the internal probe components have disipation limits.
I never found these limits to be a problem.

Let's see some more Hints and Tips.
Mike

Hints and Tips
 

I made a high voltage probe with a string of 10meg resistors added to an
existing x10 probe. For frequency compensation, I only used a 'gimmick'
capacitor. This was made by twisting two pieces of 26 awg wire loosely
together. To trim the response, we started with a much higher capacitance
than necessary and kept cutting off the end till the response was right.
Then brushed on corona dope to keep the cut ends from arcing.

"amdx" wrote in message
...
Hi all,
I'd like to see a thread on hints and tips you have picked up or devised
while developing circuits.
I'll give you one to start;
While involved in the development of a couple of class E amplifier
products
the collector voltages peaked at over 600 volts The scope was only capable
of
displaying 400 volts. I put an attenuator together that made the probe a
X20 probe,
while still keeping the HF response.
Parts used;
BNC T
BNC to F connector adapter
F connector
920k Resistor
100 pf capacitor
Heat shrink
Brass shim stock to make a cover
I'm sure other parts could be used, these are what I had available.
See the attached drawing for more details.
The resistor and capacitor values may need some adjustment for you probe.
I used the internal calibrator and adjusted R and C values until I had a
sharp
square wave and the proper voltage reading
I made a shield from brass that corrected some ringing (ISTR).
I do recall the shield was important.
Be sure to insulated the lead that passes through the F connector.

Yes, I know the probe cable has a limit to the voltage before it arcs.
Yes, the internal probe components have disipation limits.
I never found these limits to be a problem.

Let's see some more Hints and Tips.
Mike