Hello. A friend gave me a 12" monochrome CRT with its circuits that was taken off an injection molding machine (most likely from the control console Sandretto Selec 90). As I haven't been able to find documentation I started reversing the circuit to understand the meaning of the 10 pins on the card edge connector.
There is the PSU, the HV generator and two ICs TDA1175P (vertical deflection) and TDA1180P (horizontal processor). I write here in hope someone was into these circuits and can help me understand what I need to get it working. Checks completed so far: fuses don't blow, CRT filament glows, there's a 14 kHz whine (I cheated using an audio spectrum App), 12Vdc is present. Nothing on screen. The closest documentation I could find is this service manual http://oz1db.dk/hp/omnivision_man_lp06xx_rev0_0611.pdf, however I'm missing something. The 10-pin connector has 3x GND, 1x 12Vdc (output), the 3 contacts for (what I think is) the remote brightness control, 1x not connected. I am left with one contact going to a 2N2222 which should be "video input" and another going to the TDA1180P horizontal processor. Where is the VSYNC input? Not needed? I've assembled an Arduino with the TVout library and got no reaction from the CRT both with just the [video signal] and [video signal + TVout sync output to the contact going to the TDA1180P]. The only difference between the two input configurations is that when I add the sync signal I hear a very low frequency buzz coming out of the screen circuits. I haven't been lucky enough to find a schematic diagram with both these ICs and just one sync input, and I've finished my guesses. I wonder if someone in this great community has experience with this circuit configuration and can suggest what kind of signals it is expecting. Also, should it show something with no input signal, or at least some noise? I know the dangers of EHT and I would try all low-voltage checks first. Thank you, Paolo -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to neonixie-l+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/CABj2VaZqsUbWbGVfA7SATQutdJgzUDFEW2eEd8WY23F2e3fZFQ%40mail.gmail.com.
