Worked on the juke a bit today.
One of the problems with it that there was a pretty loud hum, even when there was nothing playing. The cause was quickly found: The fluorescent ballasts (esp. the one on the front). The originals were still in there. These are of course the old-fashioned transformer type. Transformers can start humming at their supply voltage (f.i. because of age) and this indeed was a clear 50 Hz hum.
So I had been thinking about replacing them with modern-day electronic ballasts.
The advantages are clear enough:
1) no more hum (most important one in this case)
2) saves energy
3) longer tube life
4) no starter required anymore
5) "instant" start, no flashing
6) the tube is run on a high frequency (f.i. 50000 Hz instead of 100 Hz) which gives a more steady light
7) a bit more light
So...I searched and searched and searched for 30W electronics ballasts but couldn't find them. Except for this one:
http://www.ebay.com/itm/Electronic-Energy-Saving-Fluorescent-Light-Ballast-30W-/230718596170?pt=LH_DefaultDomain_0&hash=item35b7e6644a#ht_1544wt_1297It was so dirt cheap (and also looked that way) that I ordered three. They arrived last week. They were smaller then I had expected. I opened one and was amazed with the extremely simple electronics required.
It was screaming China all over the place. Engrish names on the box (the boxes looked like firework boxes). The "schematic" on the label indicate that the left two (white) wires are Ground....mmmm weird.....well they're not of course, they are actually the 230V mains connection :S
The PCB quality wasn't that bad, but I am the entire thing wouldn't pass any UL or European safety norms......
Soooooo, what to do....
Well I thought I'd give them at least a chance. I replaced the worst humming original one and .......I was impressed. Of course, because no more starter is needed I needed to re-arrange the wiring a bit but that was easy enough.
Anyway, it worked great right away, indeed no flashing start-up.
I had the jukebox turned on for an hour or two and nothing bad happened. Then I checked the temperature (by hand) of the electronic ballast and it was completely cool (room temp.). This was a HUGE difference with the original ballast which got pretty damn hot....
Then I checked the tube temperature and this was also running much cooler than the tubes which still had the original ballasts.
It's very clear that this seriously saves energy, esp. if you have 3 tubes running....I mean, this box looks so cool that I'll want to have it turned on just for the cool lighting...
So.....because I will NEVER let the jukebox powered on when I'm away, I decided to use the little Chinese fellows...
Everything is originally fused so...let's say little can go wrong
Oh and of course, the hum had completely disappeared after I had replaced all three ballasts. Me like !
In fact, the less generation of heat if a very good thing for the artwork on the several glasses in the jukebox, and this made me think further, that this would also be a good solution for our cabs. Of course, because we mostly will not have these games on for very much hours, the power consumption difference is not that big, but generating little (or at least much less) heat right behind the (precious) marquee is a very good thing.....
It also saves the worries about starters etc.
It's not like I will now go exchange all the original ballasts in my cabs, but I think I will consider doing it on my next restoration(s).
