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Test - Connect a speaker or headphones to the "SPKR" jack. Apply power to the board.
Connect an antenna to the upper-right pad of T4 or the pin 2 pad of where mixer M2 will be
installed. You should hear band noise, mostly static, at a very loud level and very restricted in
bandwidth due to the action of the crystal filters. As you are listening, rotate trim capacitor to
change the LO frequency being injected into mixer M1. Starting with the capacitor at minimum
capacitance, (the highest sounding static) rotate this trimmer until the lowest sounding static
occurs. This adjustment will be used to optimize the LO injection point to center the received
signal in the middle of the main crystal filter in the final receiver alignment.
Your Measurements/Observations - ______________________________________________
____________________________________________________________________________
VFO
[ ]
Wind and install inductor L13. Use the supplied shouldered nylon washers on either side of
toroid and the nylon screw and nut to secure it to the PCB. Tighten until the wound toroid is
snug, but do not over tighten and strip the screw threads. Cut off excess screw material
protruding through the nut.
[ ]
Install trim capacitor (orange color) TC6.
- Figure 16 -
17
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