[Nathan Slingerland]

Thanks for that clarification Arran. I was muddling together 'Neutrodyne Plus' with the other TRF sets.

One small correction though - the Model 86 still uses a pair of 71A tubes for output. Model 87 uses 45 tubes.

   

I have adjusted the hum control to minimize hum. It does do that, although there's still a minor audible hum present.
I don't really think it's a problem but Mike ran into issues with hum on his Model 86.