If the complaint for NEC P8000 printer would be a missing line across the printout, immediately we will suspect the printer head or the ribbon perhaps sometime the ribbon hide. Among so many brands of dot matrix printers, only this model has tend not to fault which is the printer head and the printer driver ic's pampered.
If resolve replace the printer head without changing the main board or checking the printer driver ic any kind of short circuit, then chances are good high that after you switch it on the printer, the printer head would immediately breakdown again.
Thus it's wise for you, if you ever comes across this connected with printer, besides replacing the printer head, you must check the six printer driver ic on comprise board. When it comes to printer head, you can a 1 or send to an experienced person to refurbish it. The real question is, how do we check or test the printer driver ic's? It's simple, take out the main board and you will see that couple of different methods six ic's that have similar part number which will be the STA476A.
If at least one shorted, it will short the printer head pin. Each printer driver ic control 4 pins thus six printer ic would thanks 24 hooks! That's why in the market, they named it as 24 pin dot matrix model.
Normally I would personally use huntron tracker to evaluate the signature between the perfect and wrong ic. It's very easy to look for the culprit if you possibly could compare them. Using an analog meter also can do activity. Compare the resistance of all printer driver ic's leg, if your current any shorted printer driver ic, the meter would register the reading normally the needle would kick to most far true.
Sometimes enthusiastic about more than a single ic shorted. Once you have determined which ic that gave way, solder versus each other and replace with a 1 and you could have just completed a printer repair occupational.
Whether a person checking the NEC P8000 printer or any brand of dot matrix printers, use the procedure above to try out all the printer driver ic to be able to switch around the printer. This not only saves your new printer head, it could help you save money of not having to buy a good solid mainboard.