Heathkit ol-1 oscilloscope help. Can't get solid spot during setup procedure.

[jasonguitar]

My uncle gave me this cool Heathkit OL-1 scope years ago and I never used it. I obtained all the documentation, cleaned, re-capped it and fired it up and everything seems to work. Problem is that following the start up instructions I can't get a solid spot. All settings are per the instructions with the vertical and horizontal gains zero-ed of course. I get a 3/4" diagonal line like a forward slash. Anybody have a suggestion?

[Enzo]

OL-1 or O-11?

[jasonguitar]

OL-1 or O-11?

Its an OL-1. Wish it was an O-11

[jasonguitar]

Here's a pic of what I'm getting. A nice old tech I met at the YMCA told me to adjust the astigmatism setting but this unit doesn't have one. How can I fix this?

[JHow]

Hell. Just curious, but I didn't see the attachment?

[jasonguitar]

Hell. Just curious, but I didn't see the attachment?

That's strange. Its showing in my browser on both my macbook and pc.

[bob p]

I can't see it either. I guess that explains why you can't get a solid dot during setup.

[bob p]

the problem is that you hyperlinked to an image on a secure mail server at gmail. one has to be logged into your account to see the image. notice the "https" prefix in the link.

why not upload the image here as an attachment?

[jasonguitar]

Attached it above. Thanks.

[jasonguitar]

I assume that what would be an astgmatism control is set by a fixed resistance on this unit. I started replacing resistors which had drifted a bit in value and the problem has improved quite a bit. Guess I'm gonna have to go all the way now! Wish I knew what resistor I could replace with a pot to add the control I need? Anybody?

[Enzo]

The sure doesn;t look like an astigmatism problem to me. Astig is like a focus, the beam will look fat or smeared.

SO I can;t see the whole panel, are there V and H size controls? Do they affect the image? Does turning the H and/or V gain up and down affect the image. Does slowing the sweep speed way down affect the image? And H and V position controls, what do they do?

We don't know yet what we are looking at. For example, what if the tube is partially rotated in its holder, and that is a short horizontal line now at an angle? If the position and size controls move along the line and perpendicular to it, then we have that. If the image moves horizontally and vertically in response to the controls, then the display really is an angled line.

If you slow the sweep speed down, then the line ought to resolve into a bright dot sweeping back and forth. Whether it does that or not is a clue.

ANy chance there is an X-Y switch on this thing, on the back if not the front?

If this is an actual 45 degree trace with no input, perhaps a poper supply has large ripple and we are seeing an X-Y plot of that ripple.

[jasonguitar]

Yes there are V and H gain controls which function properly. H and V position controls function properly. The H gain will stretch that line out straight across the screen and the V will raise the image straight up so the crt tube seems to be positioned correctly. As you can see from my two pics, the line has become shorter after replacing some resistors. I will have to go to the local shop tomorrow and get more replacements as I didn't have all I needed to finish the job. All electrolytics have been replaced. This image is with no input and all controls in their initial positions according to the startup procedure in the OL-1 manual. The switch on the back is int/ext sync switch.

[Enzo]

OK so you can get the trace to go all the way across horizontally. Still at that angle, or does the vertical dimension stay the same?

How about that sweep speed question. Turn the sweep CCW, is it still a steady line or do you now get a spot moving back and forth?

[jasonguitar]

Yes its stays at that angle. If I just adjust the V and H position, that same shape moves around accordingly and does not change its shape. If I adjust the H gain it stretches out and becomes sort of a parrallelogram from left to right and raising the V gain just widens that shape from top to bottom. Adjusting the sweep gives a steady line unless I raise the H and V gains, then I get some movement.

[Enzo]

Set the sync switch on the rear to internal.

Lower right control is the horizontal selector, where is it set?