[TN Allen]

Yes, the yellow wire is to be cut and connected to a 3rd DC PS to power the R-18 radio section. I don't need that voltage though for the audio section #26 and #71-A tube filaments so I'll leave it out of the circuit. I'll cut the yellow wire before connecting the new audio section and insulate the ends.

I'll also connect a wire between one output/speaker banana jack/post on the PS to the junction of the blue/gray 2000 Ohm resistor and the black 30 Ohm resistors either side of it. This appears to be the correct location for that connection, looking at the schematic.

I think I have everything assembled and correctly soldered, I should try connecting it all together and providing power, though I must admit to some reluctance.

I have one other question regarding the center tap on the 700 Volt Hammond PS transformer, does it really connect to the chassis ground? I've soldered it to the ground lug on the 3 prong AC connector, which is connected to lug 9 on the terminal strip and to the chassis. In other words, the 700 Volt CT wire, and the ground lugs on the terminal strip and the AC input are all connected to each other and to the 1/4" Aluminum chassis plate.

Regarding using the new PS and audio units for instruction. The new campus radio club faculty advisor and I looked at the schematic yesterday. He knows about as much about the circuit as I know, but finds it interesting, the students may also. I've offered use of both if they do want to use them, as well as two Radiola 18s that need work. I'd lend them the one working R-18 I have as well. I suspect that if and when I have the new sections working and safely assembled they will go to the campus radio club and be used to explore tube technology. As I mentioned earlier I teach at Maine Maritime Academy, our Engineering Dept. students are working toward a Coast Guard license. They have varied interests and may appreciate an opportunity to work with tube radios.