When I turn it on I get a loud sound like a bullet ricochet and a slight flicker then nothing. But it boots up and plays fine. Everything seems to work.

I thought if the LED on the MPU is bad the game won't boot.

Should I replace the LED?

Thanks

Bob

Thanks Cody,

The credit knocker on this game is the old coil knocker - don't think that's the sound. I made a video of the boot up. As soon as I flip the switch it makes that sound. And notice the LED doesn't blink.

Could the LED be bad and it still boots?

Thanks

Bob

A little scary to touch a test point to ground but after a close look at the schematic I decided to give it a try. The LED did not come on. I tested it after the game was booted and in attract mode. I think it's dead.

I checked my parts drawer and I don't have a 5 MM LED. I do have a few 3 MM LEDs. Will that work?

Thanks

Bob

I put in a new 3 MM LED. I re-installed the board and only connected J4 to test. I got a loud buzz from the speaker and no flash. I don't think it booted. I pulled the board again and put it on the bench test. 5 volts at TP5 and 12 volts at TP2. No LED flash.

The LED is # HLMP1700 from GPE:

https://www.greatplainselectronics.com/proddetail.asp?prod=HLMP1700

Not sure I installed it correctly. Someone scratched a "+" on the back of the board so I installed the long lead into that hole. (looking at it from the top side the "+" is on the right.)

Now I got a real problem.

Bob

IMG_1130 (resized).JPG

IMG_1127 (resized).JPG

Thanks mb,

Good to know it's normal.

Now if I can only get the LED thing working.

Bob

I been looking over the schematics and the LED. The LED has a long lead (anode +) - (the short lead is the cathode -) Because someone scratched a "+" on the board that's where I stuck to long lead. According to the schematic the anode should connect to the R29. Looks like mine is connected to Q2. I think I have it installed backwards.

Can someone look at the photos and verify this?

Bob

led (resized).PNG

led 2 (resized).PNG

Thanks guys,

My LED doesn't have a flat side - neither did the old LED. But I installed a new one with the cathode (short lead) to the right and it works fine now. What screwed me up was someone scratched a "+" on the back side of board and it was on the wrong side.

The new LED flashes very bright during boot up but it stays on after boot up. Not as bright as the flashes but it's lit. I'm guessing it's because it's a smaller LED.

Thanks again.

Bob