[Dan Pierce]

It is not quite as easy as stated by Michael if you want the speeds to match for track power and speed sensing. I have done 5 of these and here is what I had to do:

The non-sound block is by far the easier one to motorize as follows for aa analog track powered layout (non MTS/DCC):
swap out the non-sound truck for a powered one.
Find a 4 pin power connector and add at least 6 pairs of back to back diodes on one motor lead to equalize the power to match the A unit.
Tie the power leads to the 2 wire power cable coming from the A unit as well as the inner power block leads.
Add weight over the powered truck.

For the sound block, you need to reuse the sound sensing axle and add a gear to it, and move the sound sensing board to the new motor block, or move the guts from the new block to the old block.

 

[Dan Pierce]

Does the Jenny power block have the speed sensor special axle for the LGB B unit sound?

 

[Dan Pierce]

F7A units had motor blocks and gears only. The B unit dummy block had one special axle with the speed/chuff sensing 'magnet?' on it for the hall effect sensor in the dummy block.

It is my understanding that this one was different than the Mogul axle.

The Mogul rear axle had the gear, magnet, and steam wheels. The F7B did not have the gears on the axles.