Film-Tech Forum ARCHIVE: Kinonton Dowser Won't Open

This is topic Kinonton Dowser Won't Open in forum Film Handlers' Forum at Film-Tech Forum ARCHIVE.

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Posted by Ken Lackner (Member # 1002) on 09-27-2003, 10:52 AM:

Kinoton FP-23C. Dowser closes just fine, but won't open unless given a little push. The strange thing is it doesn't have to be pushed all the way open. Just enough to get it started. Suggestions?

Posted by Steve Guttag (Member # 268) on 09-27-2003, 11:19 AM:

Ah the sea-saw douser...what a load of crap that was!

Depending on vintages...there are various circuits...one has a boost voltage to open the douser and another voltage for holding it open. There are also 6V and 24V varieties.

I would first find out if your douser is mechanically clean. Then I would determine if it has a boost circuit and verify the cap is charging properly. Kinoton also offers a douser speed-up circuit (essentially a boost circuit that hits the douser with a higher voltage to get it moving).

Steve

Posted by Ken Lackner (Member # 1002) on 09-27-2003, 02:18 PM:

If you could please post detailed instructions on how to go about troubleshooting this, I will print it out and take it to work with me.

I did clean the shaft and lubricate it. These projectors are very old and there is a lot of junk accumulated on/in them. Mabe it just needs to be cleaned a little more.

Posted by Ken McFall (Member # 845) on 09-27-2003, 02:44 PM:

I may be wrong.... but lubricating the shaft is possibly the wrong thing to do. The assembly is in a very warm area and it can get quite dusty. Dust and lubricant makes a goo that will make things worse... it's fine for a while then starts sticking again. I've not got a manual to hand but I'm sure they are not intended to be lubricated. I'm sure Steve will correct me on this if needed.

The later versions use a rotary solenoid.... which has the same tendancy to stick from what I've seen.

Posted by Peter Hall (Member # 695) on 09-28-2003, 08:19 AM:

I agree with Ken. We have rebuilt dozens of FP20s with the original 6v push - pull solenoids and have had no problems with 6VAC supplied. Srrip the assembly completely, clean and if necessary use a very small round file to make sure movement is free. Make sure you really have 6VAC RMS - measure it on an AVO or use a digital meter and convert (8v P to P = very roughly 6V RMS). We hate the original Kinoton lx

Posted by Larry Shaw (Member # 388) on 09-28-2003, 08:26 AM:

I can only agree with the clean, don't lubricate comments. Often just a few squirts with "tuner cleaner" will do the trick. I'd have to do some research, but I don't think the FP-23C's had 6V coils, only 24V. None of them had rotary solonoids.

Posted by Ken Lackner (Member # 1002) on 09-29-2003, 05:25 PM:

Larry,

Page 25 of the manual that shows the diagram for the "Dowser blade and changeover coil," one of the items listed is "dowser coil assembly 24VAC." There is no mention of a 6V coil. Also, the page (no number on the page) that lists the spare electrical parts does list a "Picture change over solenoid."

So, just how do I troubleshoot this? ("Measure with your volt meter and make sure you really have 24VAC." OK, how do I do that?)

Posted by Gordon McLeod (Member # 33) on 09-29-2003, 10:36 PM:

THere are 3 wires going to the change over
One is common and one is open and one is close
The common will be connected to the common terminal of the system and is probably easiset to find on the automation
measure acros it and the coil to determin the voltage when energized
On the FP20's it is usually dirt on the shaft that makes them stick