Easy Receiver Kit - Pete WK8S

Easy Receiver Kit 

Sold by qrpkits.com ––– Pacific Antenna

Features:

·       Easy to build and use.

·       Inexpensive at $25

·       No toroids to wind and only one adjustment to set the receive frequency range.

·       Assembles in 1-2 hours.

·       Covers approximately 75kHz of the 40M band.

·       Direct conversion design with a bandpass filter, NE602 mixer and LM386 audio amp. 

·       Mates with Easy Transmitter and Easy Audio Filter to make a QRP station. 

This kit is perfect for a beginner and fun for the more experienced. Its low price won’t strain even a modest budget. I built this for a friend and really took my time to enjoy the experience. I spent maybe 3 hours total to construct and adjust it. The downloadable manual provides clear, concise construction steps with lots of pictures and diagrams. No guessing needed here.

The Easy Receiver is a simple Direct Conversion circuit using the venerable NE602 as a mixer. The mixer receives signals from the antenna after passing through a bandpass filter to limit them to the 40 Meter range. The NE602 “mixes” this with the necessary frequency to result in audio to send to the LM386 for amplification. There are two external potentiometers. The R1 pot controls the voltage to D1 varying its capacitance which in turn controls the NE602 oscillator to “tune” the desired resultant frequency for mixing. C6, a trimmer capacitor, follows after D1 and is adjusted to set a 75 kHz receive range this circuit provides. The second pot R2 controls the amount of amplification the LM386 provides. 

I found the Easy Receiver was quick and easy to construct. It hears quite well as is characteristic of Direct Conversion receivers. The LM386 provides plenty of amplification for headphones or a small speaker. The audio is clear and pleasant.  Selecting a desired signal requires slow and careful tuning. This is expected with such a simple circuit but not difficult.  A bit more precision is required in adjusting the C6 trimmer to select the range for the receiver for optimal results.

This is great value and fun simple DC receiver to build and listen to.