I populated the circuit board and made all remaining connections (... except one resistor which I just noticed from the picture is missing in the bias circuit).
Next, will be a lot of continuity testing, tightening up mechanical connections of the pots, switches, and other components. Then, I'll follow a power-up sequence and do some testing to ensure everything is in the right place. Rob Robinette has a sensible procedure I planned to review, but I also just found this one by one of the amp builders I like (retired FAA technician who claims to be a hobbyist but is clearly a master of his craft), and am relieved to discover that I have already followed all of his steps up to this point!
You may notice some of my components have a black mark on one end. These are capacitors, which are designed sort of like ... Drake's Cakes Yodels or home made jelly rolls: two sheets of paper or plastic stuff rolled up together with electrolytic cream filling between them. The two terminals sticking out are each connected to one of the two sheets. The sheet that ends up as the outer most layer acts as a shield in the same way cable shielding works, so you always want the terminal that is connected to the outer layer closer to ground in the circuit to bleed off any interfering radio signals. The thing is, not all capacitor manufacturers mark which terminal is connected to the outer layer, so one has to just listen to them to figure it out. By connecting test leads to each terminal of a capacitor and plugging them into an amp, you can almost always hear a slight hum just from ambient RF and nearby A/C circuits working. By reversing the connections of the test leads - switching them back and forth - you can hear which way is quieter and identify the terminal connected to the outer sheet. and mark it so it's easy to orient correctly when placing in the circuit.
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