I set the dips to free play and powered on to steady cp lights. Virtually no voltage drop to aux board at 5.3v.
I checked for AC at the 10.3v on the ar, 0.0 steady
I pulled the board and reseated all socked chips and attempted to force test mode. No sounds from cp buttons, nothing happened when I hit tilt switch, Just steady CP lights...
Again verified all voltages good at ar and game board. Guess it's time to send it in...
Since I had my meter and Andy guide in hand, I opened up the back on my only other vector and checked the output of.x y, ac was good but x out was 1.9dc. Spot killer on (801). Game plays blind. Should I be sending this asteroids pcb along with it, or is that a monitor issue? Man, wishing I hadn't passed on all the cheap scopes through the years.
A few minor things:
- 5.30V is a little high for the main or aux. You want the aux at about 4.90 (relative to the GND on the aux), and the main should end up around 5.10-5.15(ish), relative to the GND on the main, depending on how clean your edge connector fingers are. Adjusting the AR will affect both main and aux at the same time, but the aux will always be a little lower than the main.
- AC at the 10.3 test point should not be zero. Something is up with that measurement. There should be some ripple, and a healthy big blue will result in between 0.200 and 0.350V AC usually. However there's also another known issue here: What meter do you have? Any of the sub-$25 'Harbor Freight specials' have a known problem in that they will not measure small AC values (under a volt) properly. You know if you have one of these because the range selector knob only gives you two options for AC, 200 and 600V, and all of the meters with this problem use the same chipsets. If you have one of these meters, you'll need to invest in a $25-40 one on ebay, which don't have this issue, and can be used to measure the ripple.
- Based on what you're saying, the CPU isn't running. It's probably watchdogging, which means it could be anything on the board. So that's something you're gonna want to send in, unless you want to get a logic probe and learn how to get more in depth (and even then there's no exact science to debugging these, but you could check a few more simple things).
- Regarding the Asteroids, if it's playing blind, that means the CPU and most of the digital side of the game board is working, which is something. There could be digital issues that are screwing things up enough to mess up the video output, as that 1.9V DC is a red flag. However that also could be caused by something bad in the video section as well (which is far more common, and the more likely case here). Unfortunately you do need a scope to know more here.
However, you should try the self-test trick on the Asteroids as well, as you might get different results, and hear beep codes in self-test if there are bad RAM, etc. Also, the crosshatch image in self-test is larger and stable, and might be good enough to cause the monitor to kick out of spot killer (or behave differently), so it's worth a try. My guess would be that you have analog issues on the game board, and likely monitor issues as well, as this is common for most Asteroids cabs , if they haven't been gone over. But the 801 is the most beefy of the b/w vectors, and is solid once rebuilt properly (and they have a whole host of common issues, but that's another topic).
Spot killer LED on (on any vector, color or b/w) means there is no deflection current happening in the yoke. This can be due to two things: 1) The game board isn't outputting valid XY signals to the monitor (i.e., one or both are missing, or one or both are distorted enough to not keep the spot killer happy), or 2) The monitor has issues with the deflection system. Or potentially also 3) Both.
Feel free to PM if you want details on sending anything in, but you're welcome to anytime.
