[Ron Ramirez]

http://www.philcorepairbench.com/tips/svctip43.htm

I came up with that mod. Model 81 and 84 have the "gimmick" but Model 80 did not, so I tried it in an 80 and found that the "gimmick" cap improves the performance of the 80.

You need two wires. One gets soldered to the wiper arm of the volume control. Another is soldered to the cathode of the 36 det-osc tube. Make each wire long enough so that they will overlap by an inch or so where they meet. Twist these wires together where they meet with the insulation left on each wire so they do not actually make contact with one another. This gives the effect of a small value capacitor.

The voltage involved is low. Any old hookup wire will do.

The same link above mentioned my other mod of changing the 9K resistor to 13K, 3 watts.

These mods really do help the performance of Model 80 sets.

As to the speaker cone, I have a friend who brushes mineral oil on all of his speaker cones. You don't pour the stuff on the cone; put it in something that fits the brush, and then carefully brush it on the cone.