These instructions go part by part, section by section. Includes information for identifying parts, placing parts on the board, and checking your work.
Board 1 includes all the front end sections of the receiver - VFO and Amps, TV & FM Filter and Bandpass Filters, First mixer, Post-mixer Amp and Xtal Filter.
Board 2 is the tail end of the receiver - Second Mixer, Crystal Oscillator, 455 IF Strip, BFO and amp, product detector, and the Audio Amplifiers.
The boards are intentionally large to help construction.
Construction aids are the following: large board size, definite breaks between different circuits, wide circuit traces, enlarged soldering pads, slightly enlarged hole sizes, and plenty of ground plane area.
When building a receiver of this complexity, self diagnosis of the receiver was a very high priority. Every LED on the board tests circuit functions. It is like having a built in oscilloscope.
In all the amplifiers, the LED is in the drain/source circuit of the MOSFET, showing the current flowing in that amplifier. If improper current is flowing through the MOSFET, it is quickly observed by the LED. The Mixer LED brightness is a direct indication of oscillator drive, and automatically tests the output of the oscillators and the mixer circuit readiness.
The only sections not covered by the LEDs are the Input Board (TV & FM Filter, RF Amplifier, and Bandpass Filters), the Crystal Filters, and the Audio Amplifiers. LEDs at the Bandpass Filters and the Crystal Filters indicate which one is active for operator convenience.
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