Re: IJ BR's???

I had a BR go bad in about a year on a TZ. When I went to replace the
BR, I noticed that the heatsink was warped. I could tell by the
pattern the heat sink compound had left on the sink. I cleaned the
compound off and set the heatsink on a flat surface and sure enough the
heatsink could be rocked from side to side..

I sanded the heatsink down until it was perfectly flat, added a thin
layer of compound, screwed the BRs on and soldered the unit back into
place.

This is just one more thing to look for while working on these
boards...

John


garavaml wrote:
Yup.. I cleaned off the old compound and added new... After screwing it
down, I touched up the solder joints again... Guess I'll see how long these
last... Unless I should do the caps too...

Thoughts? Opinions?

Thanks,
MIKE

"Joseph A. 'Tony' Dziedzic" <tony@xxxxxxxxxxx> wrote in message
news:zqdHf.301$CZ4.214@xxxxxxxxxxx
When you installed the replacement bridges, did you clean the old heat
sink compound off the heat sink and apply heat sink compound to the
bridges?
Did you securely tighten the mounting screws that hold each bridge to the
heat
sink before you soldered the assembly to the PC board? Poor heat
dissipation
can lead to premature bridge failure, and tightening the mounting screws
AFTER
the bridges are soldered to the PC board can eventually lead to cracked
solder
joints (in which case the bridge probably didn't fail).

Joseph "Tony" Dziedzic

In article <k%bHf.11829$2O6.389@xxxxxxxxxxxxxxxxxxxxxxxxxx>, "garavaml"
<garavamll@xxxxxxxxx> wrote:
My wife was playing IJ today and hit both flippers during multi-ball and
bam -- reset... I replaced the BRs and am back up running again, no
problem...

Here's my question... The BRs were replaced less than a year ago and the
game probably has less than 200-300 plays on it since. Does it seem odd
that they needed to be replaced that quickly? Is there something else
going
on here causing the BRs to go go out fast? Any ideas? Are some BRs
better
than others? She always hits both flippers at the same time, but that
can't
possibly be it, could it?

Thanks for any info,
Michael



.

Relevant Pages

  • Re: WTB: Heatsink for BOP over BR1 and BR2
    ... The rule was that you didn't solder ... I like having both bridges sharing the larger mass of one large heatsink, ... how much heat would you have to apply to an aluminum heat sink ...
    (rec.games.pinball)
  • Re: IJ BRs???
    ... I noticed that the heatsink was warped. ... pattern the heat sink compound had left on the sink. ... Did you securely tighten the mounting screws that hold each bridge to ...
    (rec.games.pinball)
  • Re: Tech: TAF Bridge rectifier
    ... If anything I'd think the one heatsink bridging the two BRs would cause more thermal expansion problem than with them separated... ... As the heatsink heats up it will expand and cause more stress on the solder joints than the negligible weight of the heatsink ever could. ... This will make sure the heat sink sits flat on the BRs. ...
    (rec.games.pinball)
  • Re: Tech: TAF Bridge rectifier
    ... to cut that heat sink in half, and in a short time people started having ... As the heatsink heats up it will expand and cause more ... stress on the solder joints than the negligible weight of the heatsink ... screw the heatsink to the BRs before you solder the new ...
    (rec.games.pinball)
  • Re: Pioneer sx-727 radio dead
    ... Then suddenly today the radio went dead again. ... I took it apart and this time reheated one of the solder ... It worked flawlessly for about 3 days, then spontaneouslt theradio ... Before I could do anything the V shaped metal (heatsink?) attached to ...
    (sci.electronics.repair)