Star Gazer
Stern Electronics, 1980I got a Star Gazer, but it will only go through 3 beeps on startup and then nothing. What should I look at? It has an Alltek MPU and Solenoid board. The rectifier was hacked up, but I replaced with a new one and repined all wires with new housings. I changed out the MPU and solenoid board with the same result. What does only 3 beeps tell you?
Thanks
Quoted from pinmike:3 beeps usually means a problem on sound board or sound rom.Did you check the main fuse to see if has blown?When you power up the game are the playfield lights on and cycling?
I did check all fuses and all were good. The GI is on but, no, the playfield lights don’t cycle.
Pull the ribbon cables from J5 on the MPU and disconnect the sb-300 sound board's power to take that out of the equation.
Quoted from slochar:Pull the ribbon cables from J5 on the MPU and disconnect the sb-300 sound board's power to take that out of the equation.
Did that, same result.
The displays don’t show anything. Is there something I should check there?
Quoted from frunch:Have you tried swapping PIA chips U10 and U11?
I haven’t, but I switched with another Alltek board. Is this something different?
Quoted from frunch:Well, it's doubtful you have 2 bad Alltek boards, so let's go back a couple steps.
You said you replaced and re-pinned the rectifier board. Did you verify proper voltages at the SDU and MPU since doing that?
The voltages are as follows on the rectifier board.
6.1 VDC
216 VDC
16 VDC
6.2 VAC
45.3 VDC
I have an Alltek MPU and Alltek Solenoid DB. Voltages are good there and I have green status lights. The sound and light boards are original Sterns. I did a swap with an Alltek light board, but same outcome. I could try a swap of the sound board, but will that work from a different game?
Quoted from phishrace:Remove all the connectors on the CPU board except J4, then power up and see if you get 8 flashes.
That changes things, but I only get 7 flashes, not 8.
First flash is more of a flicker. It booted properly. Something else is keeping the board from booting properly. Reconnect cables one at a time, reboot and see which connector is causing the problem.
Quoted from phishrace:First flash is more of a flicker. It booted properly. Something else is keeping the board from booting properly. Reconnect cables one at a time, reboot and see which connector is causing the problem.
J1 is causing the problem.
The manual for Star Gazer sucks, but if you look at a manual for a Bally game from that era (which can also use the same Alltek CPU), you'll find that J1 goes to the displays and lamp board.
Install all connectors on CPU, then disconnect all the connectors on the lamp board and see if it boots properly. If no, reconnect lamp board connectors and disconnect all display connectors and try booting. Lamp board is going to be the likely suspect. Look for cracked solder joints on the board.
The manual commonly available on IPDB for Stargazer certainly does suck. I'll add that to the list of things that needed to be scanned and uploaded. It's missing most of the schematics.
For the OP, do you have original plasma displays or LED replacements?
Quoted from slochar:The manual commonly available on IPDB for Stargazer certainly does suck. I'll add that to the list of things that needed to be scanned and uploaded. It's missing most of the schematics.
For the OP, do you have original plasma displays or LED replacements?
It has original displays. I actually thought it at might be the light board, but I switched it out with an Alltek board and it didn’t help. I’ll try what Phishrace says above and report back.
Ok, so on removing all connections from the lamp board, the game won’t boot, so I replaced those connectors and took off all the display connectors. The game won’t boot. By that I mean, I still get the same 3 flashes/beeps.
So, removing everything that the J1 connector connects to still freezes it up? Are you sure all the wires in J1's connector aren't shorted out to something?
Can you leave just J1 and J4 (left side connectors on) and take the J2/J3 (right side, switches) off? What happens then?
Since you get 3 dings which equate to 3 flashes, U10 would be the culprit - but nothing that plugs into U1 goes to U10. However, the dip switches and switch returns all go into that, so perhaps there's something on the playfield switches, or the cabinet switches, that is shorted and causing a register on u10 to be messed up, which would certainly cause the mpu to stop where it's stopping.
Pull the GI and solenoid fuses out, because it will still boot at least up until the 3rd flash (solenoid is needed for the last flash on bootup) - but this will take those 2 sources of stray voltage on the playfield out of the mix.
Quoted from slochar:So, removing everything that the J1 connector connects to still freezes it up? Are you sure all the wires in J1's connector aren't shorted out to something?
Can you leave just J1 and J4 (left side connectors on) and take the J2/J3 (right side, switches) off? What happens then?
Since you get 3 dings which equate to 3 flashes, U10 would be the culprit - but nothing that plugs into U1 goes to U10. However, the dip switches and switch returns all go into that, so perhaps there's something on the playfield switches, or the cabinet switches, that is shorted and causing a register on u10 to be messed up, which would certainly cause the mpu to stop where it's stopping.
Pull the GI and solenoid fuses out, because it will still boot at least up until the 3rd flash (solenoid is needed for the last flash on bootup) - but this will take those 2 sources of stray voltage on the playfield out of the mix.
Ok, I left in just J1 and J4, and won’t boot up. Not sure about shorting. I’ll look at cabinet switches.
When you say remove the GI and solenoid fuses, you mean just on the rectifier board correct? I did that and still the game won’t boot.
Something on J1 is causing it not to boot. I would check every wire on J1 for continuity to ground. J1 disconnected from CPU board, everything else connected to all boards and displays. If nothing grounded that shouldn't be, I would repin J1 one pin at a time to see which pin(s) are causing the problem. Could be a grounded wire or crossed wires.
Quoted from phishrace:Something on J1 is causing it not to boot. I would check every wire on J1 for continuity to ground. J1 disconnected from CPU board, everything else connected to all boards and displays. If nothing grounded that shouldn't be, I would repin J1 one pin at a time to see which pin(s) are causing the problem. Could be a grounded wire or crossed wires.
Cool, thanks. I will check it out today and report back.
Checked all around for grounding issues, and fixed a couple of spot that could have been grounding out. Still didn’t work, so I took off all connectors and reseated them. Lo and behold, it works. Not sure what it did. Maybe a pin on a connector wasn’t connecting? Not sure as I did reseat all connectors before. Well, anyway, all is good, except for a few things that need fixing like switches and such.
Thanks everyone for the help!
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