Paul,
The AC probe was effectively a "simple" half-wave rectifier circuit, but designed and constructed so that it could measure a signal up into the hundreds of volts (this product was made in the vacuum tube era) and into the hundreds of megahertz.
If you do a search on RF PROBES you will find many simple circuits that use various "modern" solid-state diodes, along with a few resistors and caps - built right into the probe. These probes are "self powered" and would only require a "hot(rectified output)" and "ground" connection to the 410. Building up the probe body itself would be the challenging part. The restrictions are the reverse voltage capability of the diode, and the "frequency response" of the homebrew probe "package".
If your intended "usage" is on solid-state equipment, with voltages not exceeding the 10's of volts, then most any of the circuits should work for you.
Maybe another DIYaudio'er has a favorite circuit they can share
I also remember that the kit companies like Heathkit and EICO made accessory RF probes for their various multimeters. These are probably available for next to nothing.
Charles
The AC probe was effectively a "simple" half-wave rectifier circuit, but designed and constructed so that it could measure a signal up into the hundreds of volts (this product was made in the vacuum tube era) and into the hundreds of megahertz.
If you do a search on RF PROBES you will find many simple circuits that use various "modern" solid-state diodes, along with a few resistors and caps - built right into the probe. These probes are "self powered" and would only require a "hot(rectified output)" and "ground" connection to the 410. Building up the probe body itself would be the challenging part. The restrictions are the reverse voltage capability of the diode, and the "frequency response" of the homebrew probe "package".
If your intended "usage" is on solid-state equipment, with voltages not exceeding the 10's of volts, then most any of the circuits should work for you.
Maybe another DIYaudio'er has a favorite circuit they can share
I also remember that the kit companies like Heathkit and EICO made accessory RF probes for their various multimeters. These are probably available for next to nothing.
Charles
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Hi thanks for the great info, just had some great news the guy I brought the HP410C from has found the AC probe and its in great condition. Have to just solve the earthing clip as its missing. Also the DC.probes not working because the wire is broken, anyone know what cable I need to replace it. And also what cable and accessories I need to make the earthing clip for the AC probe.
Hello,
The service manual is here:
- http://www.ko4bb.com/Manuals/HP_Agilent/HP_410/HP_410C.pdf
Page 5-14, you will find the schematic of the AC probe.
Regards.
The service manual is here:
- http://www.ko4bb.com/Manuals/HP_Agilent/HP_410/HP_410C.pdf
Page 5-14, you will find the schematic of the AC probe.
Regards.
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