Hi All,

I just joined a few weeks ago with a Count-Down. It's given me nothing but trouble!

Starting with no key for the back box. Had to break in....that was fun! Then I replaced the lock, but with the head locked, the nut on the back of the cam fell off, so I had to break in a second time! Oh, yes, the third time was when the door closed and the bottom hook dropped on it's own.... I'm getting pretty good at fishing with a wire hanger.

I've re-pinned the connectors, fixed an issue with the power supply, re-faced the drop targets, cleaned acid damage to the MPU and replaced a few IC's, even though I think they were good, cleaned switches, pf, cabinet etc., rebuilt flippers and probably some other stuff that escapes me now.

The main issue(s) right now is(are) that the blue drop target reset coil locks on, while the other drop target banks won't reset. I've checked transistors, they appear fine. I even bought a replacement MPU, but that didn't fix the problem.

Any thoughts where to look next? and does anyone need a replacement MPU? If my original is actually good, I'll either keep it and sell the new replacement, or keep the replacement and sell the original, not sure yet. 1st have to get this beast working.

Oh, does anyone have a Count-Down back glass to sell?

Yes, did the mods and Brand new MPU. Good idea to check outputs at the boards. Ty

It's PNP

Hi all,

I'm having trouble with my Count-Down. Two coils are locking on. I've changed transistors, but they remain locked. I have a new driver board coming, hopefully that will take care of the issue, but of course don't want to blow out any transistors on the new board.

here's a question....

I'm checking the under pf transistors as per Clay's site. I've disconnected the wires that run to the driver board, using a DMM, putting red lead on the case, 1 of the transistors checks as Clay describes, .5 from Collector to Base, and .5 from Collector to Emitter. The other transistor measures .5 from collector to base, but OL from Collector to Emitter. However, When I remove it from the machine, the transistor tests good.

Any thoughts?

TIA

Yes

The blue and yellow drop target reset coils.

I've also noticed locked on lamps.

Already done

I haven't added pull up resistors yet, any suggestions as where to take the 24v from? The fuse block is not near the under pf transistors on Count Down.

Thx

Thank you, all the other pics I saw ran 24v from the fuse bus.

looking for descent Count-Down BG

I'm assuming you meant hard one

and yes they are.

sweet

Hi All,

So I just received my new driver board. Is it still recommended to install a pull up resistor, or it it unnecessary with after market boards?

THX

Thanks

Hi All,

I've been banging my head against the wall for about 6 weeks now trying to get my Count-Down running.

Fixed power supply issue, re-pinned connectors, re-faced the drop targets, new rubber, cleaned pf and cabinet, new lamps, Cleaned and attempted repair of original CPU (it actually may be good, as it boots), added a new Ni-Wumph CPU, lots of transistors for the original driver board and under pf, a new rottendog driver (to find out the day it was ordered that, while they will work with the Ni-Wumph CPU, it's better to use a Ni-Wumph driver board with their CPU), a new Ni-Wumph driver board....

Well, I've got the machine going. Turned out to be and issue with the CPU --> Driver board harness.

Sooooooo....... I'm selling my brand new, never opened, still in shipping package Rottendog driver board if anyone here needs one.

I may also be selling the Ni-Wumph board. It should be arriving at my house next week.

Also, I would sell the original CPU, I'm pretty sure it's either working or certainly salvageable, but I don't have a tester and plan on keeping the new Ni-Wumph.

PM if interested.

-Thx

argggggg,

New self induced issue.

I had 1 CPU lamp that does not light (L28), I had the bright idea of swapping ground wires between that lamp and the one next to it since I couldn't be certain if there was a bad socket on the lamp that wouldn't light as well as possibly a bad transistor. It confirmed that there is something wrong with the circuit, probably the transistor, I'll need to pull the board and check it. However, something happened, and I don't know what, but now the 5a sb lamp fuse keeps blowing as soon as I try the lamp test. I've even unsoldered the grounds to both of those sockets and it still blows the fuse. Rectifier checks good.

HEELLLLLPPPPPP!

TY

OK, Disregard that last post.

I'M AN IDIOT!!!! I'll say it loud and in front of the whole group.

The fuse blew, and I replaced it several times, removing the possible short each time in order to isolate the issue. As it turns out I was accidentally replacing the 5a sb fuse with a 2a

Put in 5a and all is well, except for the issue of L28 not working.

Lesson learned, maybe someone else can learn from this as well. At least I didn't put in a higher valued fuse.

SO, that brings me back to the original issue. L28 not lighting. There is continuity from the wire at the socket to the transistor (Q36). Q36 tests ok while still in the board.

Any ideas? Replace Q36 just in case? As a side note.... I'm pretty sure it's not the transistor, as when I had a different driver board in, the same thing was happening.

or higher, most of my stocked fuses are 10a or 25a

Maybe Digi-Key ?

3d printed perhaps?

I did, it didn't, but the socket is questionable too. I'll order some new sockets from PBR next week.

Update: I changed Q36, even though it tested good on the board. That fixed the issue, except for the bad socket part.)

Here’s something odd.

I’ve spent about 6 weeks getting my ‘new’ Count-Down to work. Lots of trouble, also my 1st system 1 game so I didn’t have any expertise with it.

After much trouble shooting, I swapped out the CPU to Driver board harness and the machine works now.

Here’s the odd thing. When I checked the old harness, btw the wires are all re-pinned, the connectors are correctly pinned and there is continuity on each wire. The harness checks out just fine and in theory should work, but when I use it in the game, I get locked on coils and lamps.

Thanks, I used Molex 05-50-0106 pins.

Thanks, It's a new CPU. I've swapped harnesses and the game works, so I'm not terribly concerned.

Hi All,

I went to play my Countdown last night for the first time in about a month. Everything was playing well the last time it was booted, this time the player 1 display was flickering and players 2, 3 and 4 displays were dim.

Ant thoughts? It has a brand new NiWumph CPU.

Thanks

I haven't checked anything yet, as I'm away from home for a few days, will check when I'm back.

Hi all,

My Countdown's displays are starting to pulsate and the ball in play / number to match displays aren't lit at all.

Any thoughts?

Power supply, connectors anything else?

thx

Hi guys,

Does anyone know what Q30 controls on Count down?

My yellow drop target bank coil locks on. Q30 appears to test badly (in circuit). I thought the pre driver was Q17, which tests good. I have not tested the under PF transistor yet.

Thanks.

It does. Thank you.

Is that on your site?

That was the culprit. OL across all legs. Removed and replaced. All is right with the world again.

Great, Thank you.

Hi,

Does anyone have the dimensions of the Countdown back glass?

TIA