Re: VECTOR: Need Help with Electrohome G05 XY monitor

Ok, I think I've fixed my problem.  This might be another noteworthy item on
somebody's tech page.  If you order a 15ST4730R 15" B&W picture tube for a
G05 monitor from Hawkeye picture tubes (or any place for that matter) and
you can't seem to get rid of the faint retrace lines and the small dot in
the middle, what you can do is lower the resistance of R518 a little bit.
Perhaps replace this 470k resistor with a 400k 1/2W resistor.  I happen to
have a 330K 1/2 watt resistor on hand so I used that, but I would recommend
being as conservative as possible when lowering the resitance.  Now I have
much more control over the brightness.  So far it's working like a charm.

Matt

----- Original Message ----- 
From: "Mike Watson" <[email protected]>
To: <[email protected]>
Sent: Thursday, June 09, 2005 7:32 PM
Subject: Re: VECTOR: Need Help with Electrohome G05 XY monitor


>
> I recently did a B/W tube swap on a 9" raster monitor at work with the
same results - turns out the tube was not the correct cross. In this case
there were retrace lines even with the screen all the way down. This was
with Video Display Corp - they did find the correct tube on the second try
with no problem.
> Mike
>
>
> -----Original Message-----
> From: Matt Rossiter <[email protected]>
> Sent: Jun 9, 2005 9:05 PM
> To: [email protected]
> Subject: VECTOR: Need Help with Electrohome G05 XY monitor
>
> This is kind of an interesting question.  I have two working 15"
Electrohome G05 monitors from Asteroids Cocktail games.  One of them had a
pretty bad tube so I decided to buy a replacement  from Hawkeye Picture
tubes.  It works great except with this tube I can't get the brightness to
come down enough.  After it warms up, I can start to see a dot in the middle
with retrace lines.  Even when I have both the contrast and brightness all
the way down I still get a picture.  I've already determined it's not the
EHT or the deflection board because they work fine with the older picture
tube.  The voltages are all correct too.
>
> So, my question is, is there a good way to modify the circuit so the
brightness voltage (G1 ?)  isn't so high?  Perhaps change the value of R516
or R518?
>
> http://www.arcadehelp.com/manual/monitor/electrohome/G05-802.pdf
>
> Thanks
>
> Matt
> --------------------------------------------------------------------------
-
> ** Unsubscribe, subscribe, or view the archives at
http://www.vectorlist.org
> ** Please direct other questions, comments, or problems to
[email protected]
>
>