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Main => Monitor/Video Forum => Topic started by: castlesteve on July 18, 2007, 11:32:37 pm

Title: Converting K7501 to STD res?
Post by: castlesteve on July 18, 2007, 11:32:37 pm

Has anyone tried this with success?  I have a 27" K7501 that I want to down convert to STD res.

I bought an 8liners chassis... and all the specs line up fine.  Just, when I plug it in, the chassis only ran for a second and quit.  NO poof.  No sound.  Now, the chassis just pulses once a sec (whine from large transformer).  I dont have the schematics for this so it is tough to know why and where.

Anyone have any input?

Thanks,
Steve

Title: Re: Converting K7501 to STD res?
Post by: Ken Layton on July 18, 2007, 11:51:14 pm

You'd have to change the yoke.

Title: Re: Converting K7501 to STD res?
Post by: castlesteve on July 19, 2007, 06:55:14 am

ok.  So why then?

Here's my logic... i may be missing something.

1) If the H and W coil impedance is the same as a STD res yoke... so then another board should work.  Now, it may/could have some alignment problems, but should technically work without overloading the chassis.

2) If 1 is not correct, then why? And what is so different about multi-sync monitors?  The yoke?  The Tube? or The chassis?   

I thought the tube is just a big drawing board for an electron gun... and the yoke just steers the electron dot ... where the chassis controls and generates the fine grain linear horizontal and vertical current.

So if you go from a higher resolution chassis to a lower res chassis, all you are doing is reducing the ability to control the yoke inbetween dots.  The frequency changes, but does the yoke care about that? 

Title: Re: Converting K7501 to STD res?
Post by: Ken Layton on July 19, 2007, 10:23:55 am

The inductance and impedance of the medium res yoke (such as the k7500) is lower than a standard res yoke. It would be like connecting a short circuit to a standard res chassis.