[Coco] Magnavox monitor

[Boisy G. Pitre]

Marty (and all the others who bothered to reply),

Thanks for taking time to help with this problem.

I was incorrect about something, and have to revise the description of 
the problem slightly.  It has been some months since I tried it to turn 
the monitor on, and I actually hooked it up a while ago.  Here's what 
actually happens:

When I press the power switch on the back of the monitor, I hear the 
high pitch wine, but as soon as I let the switch go, the whine stops.  
However, the front panel green LED (which indicates power on) NEVER 
comes on.

If I press the power switch again, it does the same thing.  As long as 
I hold the power switch down with my finger, I hear the high pitch 
squeal, but the LED does not come on.  Releasing the switch always 
causes the noise to go away.

If I recall correctly, this switch should keep the monitor on once it 
has been pressed.  This does not seem to be happening.

I've checked the fuse and it isn't burnt.  It may be that the switch 
has somehow been rendered ineffective.

I'll put a little more time in diagnosing the problem.  If I can't get 
it to work, then I'll junk it, or send it to someone who thinks they 
can fix it (and it will be theirs).

Boisy

On Feb 29, 2004, at 6:06 PM, Marty Goodman wrote:

> Hi there, Boisy!
>
> You PROBABLY are well acquainted with this, and it PROBABLY isn't the
> problem with the monitor you have, but...
>
> OLD Magnavox moniotor (8CM series) tended to have cold solder joints on
> their boards, especially those connecting the flyback transformer to 
> the
> circuit board.  If you meticulously solder-reflowed the contacts for 
> the
> flyback (and perahaps other large parts connected with the high 
> voltage and
> medium voltage circuits) it often would fix problems with those 
> monitors
> characterized by sudden onset of no picture.
>
> It's pretty quick and easy to reflow those contacts, so it may be 
> worth a
> try.
>
> Pity it's so hard to ship a monitor... I've a spare Sony KV1311CR that 
> I
> would like to get rid of!
>
> But your description of your problem... with the high pitched squeal...
> suggests you MAY have a dead component.  Perhpas a horizontal output
> transistor, and/or something driving it.
>
> Sadly, I have no tech data on the 1CM series.  I do have a service 
> manual
> for the 8CM series, tho.
>
> ---marty
>
>
>
>
>
> -- 
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco
>