Re: My Apple ][+ is now very, very sad...

["Michael J. Mahon" <mjmahon@aol.com>]

John wrote:
> This is such a disappointment. After putting in all that time to get
> my ][+ nice and clean and looking new, and having spent hours
> disassembling and reassembling the keyboard to get it working just
> right, it dies on me, mostly dead anyway. At least I got a few days of
> fun with it after I cleaned it up.
>
> Anyway, yesterday afternoon I trekked down to the basement to align
> and calibrate my Disk ][s. I turned on the lights, shut off the
> dehumidifier (its so loud!) and booted up the ][+. At first I freaked
> out because I wasn't getting any video, then I noticed that the
> Monitor ][ was just turned off, so I sighed a sigh of relief and
> turned it on. And then I started to freak out. I was greeted with a
> very icky looking screen, instead of the normal APPLE ][ with the
> little ] prompt, I got this:
>
> http://i12.tinypic.com/6c2xh6p.jpg

There is no doubt--this is *definitely* a monitor problem,
and it is the horizontal hold.

The horizontal sweep frequency is set by a number of components,
and any one of them can drift in value, leak DC, or fail open
and produce this symptom.

However, from the appearance, the frequency is off by an amount
which is usually within the range of a horizontal hold control.

If the horizontal hold control is not brought outside the case,
it may be a screwdriver adjustment through a hold in the back
or the bottom, or it may be an internal adjustment requiring
the monitor case to be opened to reach it (with a screwdriver).

If the problem is just a "stable" drift, then adjustment may
be all it takes to fix it for a long time.  But if the component
that changed changes back again, then you'd be better off
replacing it so that you don't have to fiddle with the horizontal
hold adjustment whenever the temperature or humidity changes.

BTW, anyone who has worked on TVs is well qualified to work on
this monochrome monitor.

-michael

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Home page:  http://members.aol.com/MJMahon/

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