Illustrations #HB2
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Schematic of Parts&Kits NE602/612 1st mixer - this mixer was designed to be used with a super-het circuit with an IF of 5.0688MHz with a crystal ladder filter. I will change the crystal to 7.030 to work with the direct conversion receiver design. the L and C componenets connected to SA612AN pins 5 and 4 will be eliminated and will be coupled to the LM386 audio amp. The finished direct conversion receiver is shown in the 2nd schematic below. (602 and 612 mixer ICs are used interchangeably. )

Rf Mixer from

Schematic of receiver we built.

(Click on pix below to enlarge.)

this pix is out of order but it's something else I was working on at the same time. This is my N3ZI DDS2 signal source fixin' to go into this enclosure.