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DESW Dead Flippers.

DanLewell

DanLewell

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Joined
Jul 21, 2011
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Location
Northampton, UK
I've got a DESW that I'm trying to resurrect, Andy Netherwood came a while ago and got everything else working but thought it needed a new flipper board as both flippers were dead.

I was expecting one to be dead as I had swapped this board with one from LW3 years ago when one flipper stopped working on LW3. I was a bit surprised that both were dead but figured I might be remembering it wrong so I've got a replacement flipper board and put that in but still no good. Both flippers still dead. So, I don't think it's the flipper board, although I'm planing on confirming this by trying the flipper boards in LW3 but that is at my mates house so I can't do it until later in the week.

Both flipper switches are working, because I can see them when I press the buttons during switch test.

Any ideas what I should try next?
 
Hi, Dan,

If this game is a similar set-up to L/W 3, then I saw one with a problem like this. The l.e.d's on the flipper board lit up when the buttons were pressed, but the coils wouldn't work. Bear in mind that they're still subject to the flipper enable relay on the main Cpu/Driver board.
 
Yeah, that is what's happening here. The leds on the flipper board come on but the coils don't do anything.

I'm going to try the flipper board in LW3 tomorrow, so that will confirm that's ok hopefully.

What did you have to do on the LW3 that had the problem Jay?
 
Yeah, it looks possible it is something on the main board. I'll get my multi meter out tomorrow and report back...


  • The CPU Board Flipper Relay RY1.
    The flippers are only enabled during game play (and in diagnostic mode games Frankenstein and before). The flipper enable relay turns the ground off and on for the flipper coils. The flipper enable relay is located on the CPU board at RY1, and is activated by transistor Q80 (2N4401). When entering diagnostic mode (Frankenstein and before), the flipper relay should "click" on (activating the flipper buttons; this does not happen on Baywatch and later Portal diagnostic games though). This relay is a 6 vdc, 5 amp, 4 pole relay with four SPST switches. These switches are wired into 2 pairs (this is done because there can be up to 2 pairs of flippers). It connects through transistor Q80 (2N4401) and a 7402 at 12A and 12B and a 7406 at 12E and 12F, a 555 timer at 1C, and ultimately the 6821 PIA at 11D. If any of these components are bad, the relay may not activate the flippers. Test transistor Q80 first, as this fails the most often.
 
Dan,

That particular one had all the 'Game On' logic, which enables the 'Special' solenoids (Jet bumpers & slingshots) and operates the flipper relay, inoperative due to a faulty PIA chip. The other coils also being out was a good clue.

To prove the flipper board, you could energise the relay manually. The relay will have a diode nearby, for containing back e.m.f. from the relay winding. Taking care, use a jumper wire to earth the cathode anode (plain end) of this diode. The relay should energise.
 
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Got this fixed today. :clap:

I got the parts to switch out components for the flipper enable relay. Switched out the transistor first but it still didn't work.

The 7402s had been replaced previously so we're socketed and easy to change. Still didn't work.

So, although I had the 7406s I decided to wait and get sockets for them. The sockets arrived today, desoldered the old chips, put the sockets in and boom! Back to life. :clap::clap::clap:

I then went on to fix the old flipper board (that I was expecting one flipper to be dead on) and put that back in, and that's all working now. It's probably not too hard but I was really happy working out which transistors needed replacing without help.
 
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