Optiquest Monitor no HV
 

I have a 19" Optiquest Q95 monitor, model VCDTS21554-1M which has no HV.

The strange thing is that, when it first comes on, there is B+ on the
collector of the Horizontal output transistor. The collector waveform has
the usual well-formed spike with no extraneous smaller spikes which would
indicate a shorted windings in the flyback. The base waveform is also
perfect. But there is not a drop of high voltage.

After about 30 seconds, the B+ shuts down.

I suspect some sort of an open condition in the HV rectifier portion of the
output transformer but have no way of proving this.

Any ideas?

--

Bert Christensen, Toronto, Ontario
web: http://bertc.com
An Eclectic Collection of Fine Art, Weird Recipes,
Weird Art, Good Fun & Humour

Hi Bert,

There are a couple of simples tests you can subject the FBT to at
http://www.noahtec.com/fbtest.htm

Wayne

On Mon, 31 Jan 2005 08:42:22 -0500, "Bert Christensen"
wrote:

I have a 19" Optiquest Q95 monitor, model VCDTS21554-1M which has no HV.

The strange thing is that, when it first comes on, there is B+ on the
collector of the Horizontal output transistor. The collector waveform has
the usual well-formed spike with no extraneous smaller spikes which would
indicate a shorted windings in the flyback. The base waveform is also
perfect. But there is not a drop of high voltage.

After about 30 seconds, the B+ shuts down.

I suspect some sort of an open condition in the HV rectifier portion of the
output transformer but have no way of proving this.

Any ideas?

--

Bert Christensen, Toronto, Ontario
web: http://bertc.com
An Eclectic Collection of Fine Art, Weird Recipes,
Weird Art, Good Fun & Humour