|Wierd HP-87 Problem|
Message #1 Posted by Mike on 21 June 2003, 10:28 p.m.
I have an HP-87 that has a sweep problem. I've looked around for obvious damage and have also looked for horizontal sweep adjustments. Can find neither.
Anyone have a schematic for the HP-87?
Problem: Each line starts about 2" from the left border with the cursor shown in the first photo.
Then as characters are typed, the letters are shown reversed and move from the cursor position toward the left border. After 4 characters, the charcters are displayed left to right, from the border. These characters overwrite the first 4 characters. The 2nd photo shows the result. I typed "Sweep problem".
I have used the down arrow, after the 4th character, to show what the screen is doing.
Here is the way it looks, if I don't use the down arrow after 4 characters.
It really looks like the horizontal sweep starting position is moved way to the left. Typing a whole line ends too far from where it should on the right.
I can just poke around till I find the problem but a schematic would help locate this problem.
Anyone ever see this before?
Edited: 21 June 2003, 10:40 p.m.