[Ron Ramirez]

With needed parts now in hand from Sal Brisindi and Mouser, the work on the 70 now resumes.

First of all, I need to point out an error in the under-chassis drawings in Service Bulletins 57 and 57-A.

In these drawings, the 13K, 1 watt resistor (16) is shown as connecting from the plate of the 27 oscillator tube to the end of the 5K resistor (14) which also connects to the cathode of the 27 oscillator tube. This is incorrect. The correct hookup is shown in the revised drawing, made by me, from Bulletin 57 as shown below.

   

Please note that the higher numbered parts in Bulletin 57 do not match up with the information in Bulletin 57-A (which our modified schematic is based on). However, resistors (14) and (16) do match up.

I replaced bakelite block (12) with a newer "universal" type block, as I needed a ground lug to attach the grounded end of the added 270 ohm resistor from the front end cathodes. I kept bakelite block (5) stock. Both have been restuffed with new capacitors.

I've rewired the cathode circuit of the front end tubes to match Ed's revision.

Here's this evening's progress.