Woodo wrote:
Would an expandable coupling work here.
https://www.homedepot.com/p/Hillman-3-8 ... /204775505 Some fancy threads may be required.
The main requirements of the coupling are to allow flexibility/ stop vibration and shock and a controlled twist to stop any shear forces on the control potentiometer. I have seen other flexible couplings and might have a look.
So any fixed coupling wouldn't work. If the chassis moves even slightly due to expansion then the alignment between the shaft and the Pot can move with no "give" in the drive chain that causes stress on the Pot shaft.
The motor drive is working well at the moment with enough "slip" on the drive belt to give a clutch effect so you can turn the Volume manually and still motor the Pot all the way to each end of the stop. The striker plate has to be cut to size to match the ends of the Pot track so you don't get overdrive past the end points but still get full operation. So the stop is a single point and the striker represents the gap in rotation between the two end points IE the pot isn't 360 degrees so the coupling can only be allowed to rotate as far as the Pot does. But there can be no "slip on the coupling" the coupling must always match the pot position to the coupling stop position.
So its nothing special its just the same as any positional control on a machine or CNC.
The PWM is better than a straight LM317 I can control the motor speed down to a crawl, the Velleman IR allows for toggle action or pulse so I selected the pulse which allows for a 1.5-2sec pulse that gives steps, but the pulse stops if you release the control so you have variable toggle time but a maximum of 1.5-2sec that represents about seven steps from one end of the pot travel to the other.
NB using the pulse means the dog stands on the remote it won't drive to full volume because the pulse toggle just times out.
I have loaded the TV settings etc and IR volume into a programmable handset from the velleman control fob.
It would be interesting to do proportional control with a control pot on a handset and as you turn the pot on the handset it motors the pot to mirror it but I don't have the time at the moment. There is lots that could be done with something like a Arduino but I didn't want to spend time programming..
So standard servo control would also work well the same as RC cars or planes. You could do volume, balance, bass, treble ,tilt etc.. LMAO and not use electronic control just Pots. I guess it depends on how you feel about TV set type SS tone stacks.
Its interesting that it would be just like a control desk in a mixing studio.
I should add that the shafts touch each other inside the coupling there is no air gap. So only the slightest flexibility.
Regards
M. Gregg
Login
Register
FAQ
). I also have some copper in oil Audio note from a previous build that I quite like the sound of but I'm interested in the reviews for the copper and wax.