🚀 go-pugleaf

A common misconception.

"no ripple" actually means very little in the overall scheme of things.

Your fault description puts the fault squarely on a bad electrolytic
somewhere. After checking all the PSU Caps by ESR/Substitution, move on the
the FBT drive circuit; a VERY common failure is the Electro smoothing the
~+12v rail to the the FBT Drive transistor's drive transformer.

    Craig

"Alan Liefting" <aliefting@ihug.co.nz> wrote in message
news:3CBF4DA2.95B9C167@ihug.co.nz...
> Thanks for the prompt reply Jerry.  The power supply output is stable
> and there is no ripple on the output.  This rules out the power supply.
>
> Alan Liefting
>
>
> "Jerry G." wrote:
> >
> > Check for caps with high ESR in the power supply and especially the
> > horiz scan and HV sections.  You must either do the ESR test on the
> > caps, or sub them to test them.  A standard cap meter will not do the
> > job.
> >
> > --
> >
> > Greetings,
> >
> > Jerry Greenberg        GLG Technologies GLG
> > ==============================================
> > WebPage         http://www.zoom-one.com
> > Electronics        http://www.zoom-one.com/electron.htm
> > Instruments       http://www.zoom-one.com/glgtech.htm
> > ==============================================
> > "Alan Liefting" <aliefting@ihug.co.nz> wrote in message
> > news:3CBF366B.18BBD04@ihug.co.nz...
> > Replace line o/p transistor and series fuse (used 1 ohm resistor).  Now
> > have a picture but from after about 3 seconds after turnon get a noise
> > bar travelling up the screen and the whole picture will flash on and off
> > at about a 1 second period.
> >
> > Managed to substitute the micro and EEPROM into another good monitor.
> > They worked fine.  The micro is putting out a video mute signal at a
> > guess.  5 volts is good at the micro.  The incoming sync is at the right
> > level.
> >
> > Any ideas?
> >
> > Alan Liefting