1-Locate R133 (470 ohm between pin 7 of V105 and fround) and replace with a 430 uh choke.

2-Locate C193 (1000 pf feedthrough button into antenna relay/neutralizing capacitor compartment) and remove.  Install a new buss wire between T21 and C189.  Connect one end of a 500 pf disc ceramic to the buss wire as it enters the compartment and the other end to ground.

3-Locate R172 (15K 2W on terminal board TB3 near V108) and parallel with a 10K 2W resistor now called R220.

4-Locate the blue wire between pin 6 of V107 and the coil of relay K102 and replace with a 7K 5W resistor now called R219

5-Locate R142 (3900 1W near power transformer between TB8 and the bias control and paralle with a 1K 1W resistor now called R217.

6-Locate R212 (180 ohm 1/2W on TB2 near V108) and replace with a 22 ohm 1/2W resistor.

7-Locate R213 (1.5K 1/2W between pin 8 of V107 and ground) and replace with a 680 ohm ½ W.  Measure the idle current  and  change the 680 ohm with 1K if the idle current is over 3ma.

8-Locate R214 (91K 2W on TB2 near V108) and replace with 50K 10W or 2x 25K 5W in series.

9-Locate R174 (1K 1W and replace with 470 ohm 2W.

10-Locate the blue wire between L113 (2.5 mh) and the bias source (junction R172, R220, R177) on TB3.  Remove this blue wire and replace it with a 15” length of blue wire from L113 to the arm of R143 (the bias adjust pot).  Remove the jumper installed between  the arm of the pot and the end of the pot which has the blue wire running to the bias source tie point on TB3.

11-Mount a single lug tie strip so the lug is near pin 5 of V109.  This tie strip is now TB9.

12-Disconnect the three red wires from pin 5 of V109 and connect them to the new TB9.

13-Locate C162C and disconnect the two white/rewd wires.  Re-route the one which comes from TB7 (junction of R141 and R157) and connect it to pin 5 of V109.  Cut the other wire close to where it enters the cable bundle.

14-Locate R156 (4.7 ohm 2W) on TB2 near V108 and remove it.

15-Remove the white/red wire from TB2 and cut it back to where it enters the cable bundle.

16-Add R218 (12K 10W) from C162B to TB9.  Add zener (value unknown) from TB9 to ground (cathode to TB9).
(NOTE: This last modification…adding the zener…can be omitted if the second OA2 tube is installed in its place).

See the diagram on the next page for details of installation.

After the above modifications it will be necessary to re-set the bias control and re-neutralize the final.