Posts: 4,027
Threads: 172
Joined: Aug 2005
Hi, David; are you well?
Both possibilities are valid. I am not completely aware of how is the HP82162A (HPIL standard printer, right?) head connection, but it seems to me it is not too different of the one found in the HP82143A (HP41 standard peripheral printer). The 82143A has a flat circuit connecting the printer head to the mainboard. The connection is achieved by some sort of "metal clippers" that firmly hold the fex edge to the mainboard connector. I used a small piece of nonconductive, ESD "aware" plastic to "produce" a small clearance between the flex circuit and the "clipper" connectors (Gee, I hope yopu can read this and understand... where are the English terms when I most need them?) so I could remove it. I'd guess: (the order does not mean "preference" order or the like)
1 - cold, broken soldering;
2 - bad connection;
3 - broken cooper trail in flex circuit (today this is easy to repair);
If none, maybe (just maybe) either the printer head or one of the drivers (some 8-pin DIP guys closer to the head connector) are bad. I'd not take this last possibility as the most likely to be because you mentioned there are "some" blank horizontal lines. I'd not go for more than one burned driver or head thermal dot (resistor). At least I'd not.
Anyway, other printer experts (or gurus) surely will give you better guidance.
Hope you succeed.
Luiz (Brazil)
Posts: 1,788
Threads: 36
Joined: Aug 2007
Your printhead is almost certainly bad. Check the resistance of each pixel with an ohm meter. Two pins are tied together (common). The other pins are the dots. Should be around 100 ohms each.