There was a standard 10-pin interface on video monitors back in the 1980's, so you probably have that. I know the video, vert-sync, and horiz sync were on the connector. Check pin 7; I recall that was for power and usually had a fuse on the PCB board. You should be able to find a pinout on the web.
On Saturday, April 22, 2023 at 4:29:26 AM UTC-7 Paolo Cravero wrote: > 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 [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/f895b69e-6cd6-43ca-a69c-02cc88e55412n%40googlegroups.com.
