Recent content by westal_sage

PM sent - I'll take it for 30 shipped

Thanks Andrew! PM sent.

I just rebuilt a Pac-Man joystick and put a new grommet in, but it just feels too loose to me. Its snap back to center works flawlessly - I don't have any doubt it's a brand new grommet - but again I don't like the feel of it. I've noticed that people often complain about the opposite - having...

Perhaps a silly endeavor, but I'd like to be able to pause my Pac-Man game. I read something on this the other day, and it talked about wiring up remote switches to the pause dip switch and the speaker. But it then said something like "as for turning off the monitor to avoid screen burn, I'm...

Here was my silly little idea that has turned out to be pretty handy. https://dl.dropboxusercontent.com/u/25747163/joust_voltmeter.jpg I have a switcher in a couple of my Williams games (along with an NVRAM for the high scores - works great). With a switcher that can drift over time, I like to...

SOLVED! Problem was chip 1B connection. I just started probing pins and found 1B-4 to be dead. Schematics showed that pin to go to 1G-2 via the Data Buss. Continuity check showed no connection. Reflowed solder at 1B and problem is solved.

Hi all - I'm hoping you guys can follow my logic here and give me some pointers. Problem - my Robotron upright is working great except that the screen background has suddenly turned red. Some things I've tried: Swap Q2 and Q3 - no change Was hoping to see the problem go from red to blue...

Sorry guys - b4 someone says "jeez dude don't ya read around a little bit b4 you ask a question?".... I found the whole tube donor db, etc. So I think I'm good now on my original ???s. :)

So let's say I have a Galaga with an almost great monitor. The chassis is recapped with a new flyback, the colors are stunningly bright and the image is rock solid. Only problem is, the tube has bad pac-man burn on it, and I'd like a nice burn-free tube in there. So I think, no problem - I'll...

Just a quick update to this thread. Everything is up and running fantastic with the original linear power supply - woohoo! I did a rebuild with the kit from Bob Roberts, redid the connectors to molex and put some new header pins on. As I suspected, the problem I was having with audio...

Oh ya know what I think the IND indicator lights might be the rank lights. Those pinball-style (SCR controlled even?) lights that show what rank you are thru the game (warrior, avenger, etc.)

Thanks Robotron! Well I just checked the big transformer and all the voltages are there - woohoo! They're all running a little hot - maybe about 1.3V or so higher than stated. But I'm thinking that's OK. Also, the input side connector looks to be intact - although pin 1 (center tap) is...

Original Linear PS - Output Side OK so yep this is where my questions really start coming up. I guess that makes sense, since it's the final output and that's what we now have to work with to start powering things up. Proof's in the pudding. Well, I'll start with what I'm understanding to be...

Thanks Robotron! OK yep that A011 diagram is the one I've been looking at for awhile now. And ah yes you pointed out something I wasn't seeing - the fact that we're getting those negative voltages on the output side from that 12V line coming in. But the output side of the linear is where my...

Original Linear PS - Input Side Whereas the switcher's input is super simple (just the 3 wires of the power cord), the linear's input gets more complicated. The input side of the linear PS doesn't "see" the 3 lines of the power cord at all, but rather it sees the outputs of the big...