Flasher problem – replacing some components on the Power board
Back to my flasher problem today. As reported earlier I’ve got a flasher problem and having enquired on flippermarkt.de and RGP, based on inputs received, decided to replace the 20V supply components (Bridge Rectifier BR4 and Capacitor C11) and also the ground switching circuits for the affected flasher circuits (Transistors Q39 through to Q42). I also took the opportunity to replace the pin connector for the GI lights (J121) on the board, which had been badly burnt in a previous life.
I haven’t desoldered components for a long time and a double sided board makes the job that much harder. I managed to remove all the components, but in the process ruined the through-hole plating in numerous locations – especially around the transistors. So having replaced the components in the board I needed to do some patch work:
The complete patchworked Power board
The patchwork around transistors Q39 to Q42.The TIP102s were the worst affected
The patchwork around BR4 and C11 - just to be on the safe side!
Some patchwork to the GI circuitry from a previous life - the green cable is new (mine)
With all these new components and patches, I was a bit concerned about putting the board back into the pinball machine. But I did and having plugged all the plugs back in to the board, I gingerly switched on – and the pinball worked – a miracle.
So I went straight to the test menu to test my new flashers. First the flashers – yes they all worked and seemed brighter! I was on a high! So I went to the “all lamps and flashers” test and………….
……….nothing had changed!!!!! I had exactly the same problem as before! Well at least I hadn’t broken the Power board!
But let’s look at the positives……I’ve eliminated the supply and ground switching circuits from the equation.
Or have I?