Framing is it a lost art ?

[Harry Dalek]

I have been reading past newsletters as you do

I came across the same circuit motor control circuit as in issue 14 number 3 Gary told me about.

but in issue 16 number 2 talks about the framing issue and says you need a movable adjustable opto fork ....sounds simple mmmm wonder if it is this simple as i said forgotten knowledge.

btw issue 16 number 4 is another good one on motor control for the record.

Does it mean the fork needs its own adjustment ?

Perhaps 2 forks a distance apart from each other via a bistable switch adjusted that way .

from the sounds of it there are 2 ways to do it the main motor and the fork.

[kareno]

Hi Harry,

You do have to adjust the opto fork position for the club motor controller (as you have to for most motor controllers). BUT, the speed adjustment behaves like a fine framing control when the disk is locked so you can get the last few degrees by adjusting this.

There is also some lattitude for opto fork placement because you can choose which sync hole you cover over to generate the missing sync pulse on the opto signal. By positioning the disk so that the scan hole for the first line is just coming into the viewing area, you can see which sync hole is closest to your desired opto position and put a piece of tape over it. (that's what I do anyways!)

I actually have an article submitted to the newsletter on these sorts of matters. It might not get into the next issue because, for once, Jeremy was overwhelmed with copy.

[Harry Dalek]

Hi Harry,

You do have to adjust the opto fork position for the club motor controller (as you have to for most motor controllers). BUT, the speed adjustment behaves like a fine framing control when the disk is locked so you can get the last few degrees by adjusting this.

There is also some lattitude for opto fork placement because you can choose which sync hole you cover over to generate the missing sync pulse on the opto signal. By positioning the disk so that the scan hole for the first line is just coming into the viewing area, you can see which sync hole is closest to your desired opto position and put a piece of tape over it. (that's what I do anyways!)

I actually have an article submitted to the newsletter on these sorts of matters. It might not get into the next issue because, for once, Jeremy was overwhelmed with copy.

Hi karen

Thanks i am very close to seeing this for my self , my second go..now using the hall effect sensor instead of the optical fork .

Just finished it i took what you said in and gary ,mines tested up to the mosfet i will be using for the motor ...just a touch more than your circuit
2 ic's and the transistor.

The framing part and speed control part never really gets shown until its been worked which is understandable but i think its good to see a projects evolution for others.

So for me and others the fork once adjusted thats it ? its not an every time thing i gather ...

I have not removed a magnet yet for the missing hole used in the optical fork idea i just want to see first how it gos...but it sounds like i would have to do the same thing.

I will look forward to the newsletter see thoughts on all this ,and the stuff you mentioned above on the fine tuning of the framing was new to me thanks for that .