XPost: sci.electronics.components, sci.electronics.design, sci.e   
   ectronics.equipment   
   XPost: sci.electronics.repair   
   From: excretatauris@invalid.invalid   
      
   On Fri, 08 Feb 2013 08:55:32 +0200, Tauno Voipio wrote:   
      
   > The scan system is resonated on the third harmonic to the line rate to   
   > create the S-correction for the scan, slower on the edges and faster at   
   > the middle.   
      
   That's yet another version of the widely-held misapprehension about   
   horizontal output harmonic tuning.   
      
   The *leakage inductance* of the flyback transformer is resonated at either   
   the third (monochrome), or fifth (color) harmonic of the "flyback   
   frequency", which is the reciprocal of twice the flyback time, somewhere   
   around 3, or 5 times 50kHz for NTSC/CCIR 525/625 line TV, assuming 10   
   microsecond flyback.) This has the effect of flattening the peaks of the   
   (half-sine) flyback pulses, and can be seen as either one or two small   
   dips in peak flyback voltage. In early tube designs, this was done with a   
   small winding underneath the HV winding, which was resonated with a   
   capacitor. In later designs with diode-split windings, it was done by   
   carefully controlling interwinding capacitance.   
      
   S-correction is a separate issue, achievable with a suitable capacitor in   
   series with the actual scanning current.   
      
      
   --   
   "For a successful technology, reality must take precedence   
   over public relations, for nature cannot be fooled."   
                                          (Richard Feynman)   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)