Remote Field Strength Meter

Reprinted with permission from Rudolf Graf.
For this and over 1000 other electronic circuits, review and order Rudolf Graf's Encyclopedia of Electronic Circuits on CD-ROM Vol-1 McGraw-Hill ISBN0078528119

Fe29-1.jpg (44036 bytes)

FE29-1

Description:

This field strength meter consists of a tuned crystal detector producing a dc output voltage from a transmitted signal. The dc voltage is used to shift the frequency of a transmitter of 100-mW power operating at 1650 kHz. The frequency shift is proportional to the received field strength. This unit has a range of several hundred feet and is operated under FCC part 15 rules (100-mW max power into a 2-m-long antenna between 510 and 1705 kHz). (Reprinted with permission from 73 Amateur Radio Today, 3/92, p. 44.) From figure FE29-1 from Encyclopedia of Electronic Circuits Vol. 1.)