Re: K6100 T901

You can get one here:

   http://www.cinelabs.com/wg6100/

which has link to here:

   http://arcadeshop.com/wgxy-fb/wgxy-fb.htm

$79, and comes with extra protection components and a new focus assembly.

Note, I've never ordered or used one of these flybacks, I just remmeber
seeing it recently while searching for other parts to bring a 6100 back
to life.

___
Ken

akswanson@ntelos.net wrote:
> I had suspected the triple nickel (555), and indeed it was fried. It
> also took out Q905, AND T901.. I verified this by trying T901 in a
> known good HV unit. I got smoke, and another blown Q905.. So if
> anybody knows where I can get a replacement T901 thatd be swell!
>
>
>
> > I'm not saying that you don't have a bad T901, but can you verify that
> > IC901 (555 timer as a simple oscillator) is running. A scope would show a
> > nice square wave coming out at pin 3. If it is stuck in the high state,
> > it would keep Q904 and Q905 turned on constantly and that would certainly
> > cause your problem. Of course in this state, there would be no HV output
> > at all. Check ZD900 for 13V across it. ZD900 is the voltage regulator
> > for the 555 chip. If the zener is partially shorted and there isn't
> > enough voltage across the 555 chip, then the 555 chip output might be
> > stuck even if there's nothing wrong with it. If the zener is
> > open-circuit, the 555 chip will likely have blown.
> >
> > You should remove R917 and leave it out until you can verify that
> IC901 is
> > running okay and that the transistors Q904/905 are both switching. To
> > functionally test Q905, you can add a temporary 10k (to 47k) resistor
> > (1/2W to 1W) from +Vsupply (+28V) to Q905 collector. If scope shows a
> > good square wave, remove the temporary resistor and return your focus to
> > T901.
> > If you do not have a scope but you have a voltmeter, connect your meter
> > (-) to ZD900 anode or IC901 pin 1. Use the meter(+) to measure voltage at
> > ZD900 cathode and IC901 pin 8. Both should be about 13V. Measure IC901
> > pin 3. If it is running, it should be around 6.5V plus/minus around 0.5V
> > roughly. The point here is that pin 3 should be outputting a square wave
> > having roughly a 50% duty cycle so the voltmeter should show
> approximately
> > one half the chip supply voltage.
> >
> >
> > William Boucher
> > http://www.biltronix.com
> > ----- Original Message -----
> >
> From: akswanson@ntelos.net
> > To: vectorlist@vectorlist.org
> > Sent: Sunday, August 28, 2011 9:20 AM
> > Subject: VECTOR: K6100 T901
> >
> >
> > One of my 6100s had a fire on the HV board, took out R917 and Q905. I
> > replaced those, and got smoke again.. Comparing the resistance of the
> > primary of T901 to a known working T901 I get 9.5 Ohms on the suspected
> > bad one and 17 ohms on the known good one. I get the feeling I melted
> > the varnish on the wiring and shorted them together.. Does anyone know
> > where (or have) and extra T901? Also, Is there a secondary cause, such
> > as a flyback failure that would cause this kind of failure? I dont
> > want to blow the dang thing again..
> >
> >
> >
> > Andrew
> >
>
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Received on Sun Aug 28 22:17:17 2011