Measuring RF power was always tough job. We are familiar with 1N94A or 1N270 RF probes.

Analog Device AD8307 is a small 8 pin IC having true V/DB characteristic making it an immediate choice for a simple but high quality signal measuring device for amateur station workshops.

This device requires 5V and a good PCB layout. I made this project based on application notes and IC datasheets provided by Analog Device. PCB is PTH Double Sided and except one AD8307, which is a SMT parts, all other components are thru hole type.

In view to have future expansion, Board has two BNC input Sockets & uses two AD8307s. 

To make kit builders happy, I will supply one AD8307 (Which is SMT) pre-soldered on Kits and the second AD8307  (a DIP package) may be inserted by user/kit builder, at later date.

Although, use of SMT capacitors and resistors are suggested & logical for the frequencies covered, I have used thru hole parts keeping in view simple home brewing PCB project which completes faster than with SMTs and keeping in mind the requirements of accuracy involved in amateur radio measurements.

+5V power for this board is Acquired from associated LCD Power Meter detailed below thru a 10 wire ribbon cable. 

If you are using this sensor as stand alone with a DVM as measurement unit, you will require to supply +5V to this board.

Uses:

Although designed to drive the associated LCD RF Power Meter detailed below, this sensor board may be used with your digital multi-meter to measure RF Power up to 500mhz.

By using suitable "Pick-up" unites or by connecting necessary attenuators, possibilities exist to measure RF power levels to 1 or even 10KW of RF.

Click the image to enlarge

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