Good morning everyone,
Posting here to reach a broader audience than on the CFTBL owner thread.
For quite a while I've been encountering a random issue, now much more persistent, with the ejector in the VUK of my Creature. This ejector is powered by a coil, driven by a transistor on the power board, and the 70V power rail. The issue is that the VUK does not have enough force to propel the ball into the wire ramp (at least 4 out of 5)
I've cleaned up the mechanics, changed the sleeve, even replaced the coil, to no avail. So I started to try to debug at the power board level and took an oscilloscope shoot of both end of the coil, picture attached.
From this scope shoot, you can see the drive transistor is working perfectly, the curve is a nice inversed square.
The other curve however is the 70V rail, which "should" stay flat (at least in theory).
So I changed BR3 rectifier and C8 capacitor, as these are pretty much the only components in the schematics between AC and the coil itself, at least with regards to 70V rail, but this did not change the behaviour one bit.
Given that C8 is a relatively low value capacitor (150uF), I'm starting to believe that this curve is actually normal given the huge power drain when the coil energize, and I've been looking at the wrong direction
Could someone therefore please comment on whether such a curve is expected for a 70V power rail on a WPC89 power board ?
If not, then I will keep focusing on the power board
If yes, then this means the issue is at the coil, mechanical or otherwise
Thanks and regards