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Radio1950 · 5th Nov 2018, 3:36 am

Power Meter Diodes.

Within the context of the original post.
For HF powers over 5 watts, Schottkys eg 1n5711, HP5082-2800 (this is a Vintage Forum!).

For HF powers less than 5 watts, and without amplification, you may get better results with .....
Germanium diodes, OA95 etc, but select pairs for dual reflectometers.

In practice, I have gone full circle, OA95 to 1N5711, BATx, and back to OA95 for better sensitivity at the lower power levels.

Even the VHF/UHF reflectometer section (200-500 MHz) of my Power Meter uses OA95s after trying some BAT42 and BAT85 schottky diodes at low power levels.

In practice, you probably have some adjustment control in the meter for cal, and you can just compensate for the diode sensitivity.

If in doubt, calibrate at the high end of the power scale, where diode sensitivity has less effect.

5th Nov 2018, 3:36 am	#58
Radio1950 Hexode Join Date: Apr 2017 Location: Buderim, Queensland, Australia. Posts: 428	Re: RF power meter calibration Power Meter Diodes. Within the context of the original post. For HF powers over 5 watts, Schottkys eg 1n5711, HP5082-2800 (this is a Vintage Forum!). For HF powers less than 5 watts, and without amplification, you may get better results with ..... Germanium diodes, OA95 etc, but select pairs for dual reflectometers. In practice, I have gone full circle, OA95 to 1N5711, BATx, and back to OA95 for better sensitivity at the lower power levels. Even the VHF/UHF reflectometer section (200-500 MHz) of my Power Meter uses OA95s after trying some BAT42 and BAT85 schottky diodes at low power levels. In practice, you probably have some adjustment control in the meter for cal, and you can just compensate for the diode sensitivity. If in doubt, calibrate at the high end of the power scale, where diode sensitivity has less effect.