Slow Motion drives.

[G6Tanuki]

Originally Posted by Cruisin Marine

[I]
Perhaps a slo mo drive and an added edge wise thumbwheel connected to a varicap may give the answer?

I think my idea of a slo-mo drive to the multiturn pot for the whole thing is easier.

15 turn pot and 6:1 slo-mo gives 90 turns to cover 300KHz, which sounds like a nice slow tuning rate.

[high_vacuum_house]

Just my thoughts.

How about fit the largest knob you can fit onto the receiver?. This will also help the physics of moving the knob I.E a greater torque would be developed which will mean less force required to overcome the grease in the mechanics compared to a small knob, and also with a large knob the circumference of the side of the knob is also longer and therefore easier to fine-tune than a knob with small dimensions.

Christopher Capener

[Julesomega]

Jackson made a dual ratio 36:6:1 with heavy grease allowing slip between the two ratios. They fit behind the panel with the output also brought through to the front to carry a pointer. They were supplied with an enamelled bezel about 5×4 in.

[Julesomega]

I have here a Muirhead drive as shown in Wendy's picture

without the surrounding scale shown in another Muirhead thread

and without either type of locating slots which are shown in yet another Muirhead thread

- but you've probably moved on by now