gotcha... well good job. The only thing I can think of right now is maybe there is still a cap in the psu that was installed backwards. or there is a solder bridge on the bottom side some where.
maybe check the 'optoisolator' ? http://68kmla.org/forums/viewtopic.php?f=7&t=22630#p223860 Charles MacCaps.com On Feb 27, 2014, at 6:28 PM, Keith Jamison wrote: > Hi Charles, I've already recapped the PSU, Analog Board and Logic Board > electrolytics. Should I maybe recap the metal films? (C260, C267, C268, C272, > C273, C274, C280) I have ordered replacements for C151 and C158 on the HV > side. > > BTW, two metal films went bad on me in my Mac Plus (C36 and C37 - I replaced > C33 at the same time as C36). Two metal films also went bad (split tops) in > the Classic but I don't recall the exact component labels. They were white > and on the HV side. > > I replaced the caps on the SE/30 logic board first and everything worked > fine. Then I replaced the caps on the analog board and it still worked fine. > > Only after I recapped the PSU did the problem show up. > > The analog board (minus PSU) was given dishwasher treatment after a dose of > IPA. It was the difference between night and day. When I remove caps, I > remove all of the previous solder using a desoldering pump and then some > solder wick. Then the pads get a clean with IPA to remove excess flux resin. > After soldering the new component in place, I use a Q-Tip/cottonbud soaked in > IPA to remove excess flux resin again. > > None of the caps in the SE/30 appeared to have leaked but as a precaution I > used the IPA to remove any contamination. > > The method I use has so far worked on a Classic, a Classic II, an LC and a > Mac Plus. > > The Mac Plus did go awry but I replaced CR1, CR5, CR20, CR21 and Q2 based on > some internet searching, with the recommended new beefier components. Larry > Pina's Dead Mac Scrolls prompted me to change CR29 and the Plus is working > like a charm. > > Try as I might, I haven't found out about the SE/30 PSU - maybe because it's > SONY and discrete from Apple. I have most of the knowledge, I just need to > organise the time to trace it and build a schematic. I did all this at Uni > but that's like 22 years ago now - sheesh! > > Anyway, I really appreciate all the help I'm getting, it helps to rule more > stuff out to narrow it down. It's 23.30 here so I'm going to hit the sack. > > Cheers, > > Keith > > > > On Thursday, 27 February 2014, 22:20, Hardware Mack <hardwarem...@gmail.com> > wrote: > whoops, you did change the caps... > > have you tried to unplug the hard drive? > also was there cap goo, when you removed the old caps in the psu? > you really have to get all that cap goo, it is a conductive fluid!. > > you might want to check your solder job on the se/30 mainboard as well. > maybe you have a solder bridge some where... or a cap that was installed > backwards. > > wash the mainboard... and maybe dump some IPA in the psu and then , blast > both the psu and the main-board off with the air compressor. > > > > On Thu, Feb 27, 2014 at 5:10 PM, Hardware Mack <hardwarem...@gmail.com> wrote: > replace all the LV electrolytic caps. they appear bad. > All the caps on the HV caps are probably ok. > they can be bad + leaking and you would never know until you remove them. > they can be bad even if they are not leaking. > > > > > On Thu, Feb 27, 2014 at 4:38 PM, Keith Jamison <keithjamison...@yahoo.co.uk> > wrote: > Hi Guys! > > Thanks for all the tips and things to look out for. > > I pulled the PSU and opened it on my bench. Under a magnifying lens, I > visually checked the solder joints I made when I replaced the caps. I > reflowed them to be certain. I also checked that the caps were correctly > polarised. > > I reassembled it apart from the metal lid and there was only the slight hum > of the supply when I turned it on. > > With my meter, I recorded the following voltages against what they should be > and again after 5minutes. Then I adjusted RV251 (V ADJ) and checked again. > > V# Pin Colour Expected Recorded After 5min After Adjustment > V1 #4 Orange + 5V + 5.56V + 5.39V + 5.84V (Max) > V2 #9 Orange + 5V + 5.56V + 5.39V + 5.84V (Max) > V3 #5 Yellow +12V +14.42V +10.91V +10.92V (Max) > V4 #10 Red +12V +13.83V +10.31V +10.53V (Max) > V5 #6 Green -12V - 8.81V -8.11V - 8.85V (Max) > > (I hope the table lines up okay) > > By maxing out RV251, I heard the clicking sound again, more of a 4Hz or 5Hz > rapid cheep or chirrup. > > The noise is coming from the LV side rather than the HV Supply side. Seems to > be coming more from the second heatsink with the medium and small > transformers under it. > > So, in summary, the PSU fires up and gives wildly out of tolerance readings > for 3-5 minutes, then settles down to lower readings. By adjusting RV251, the > readings cannot be made to achieve their expected values. The green cable > does not reach the -12V output state. All of this is accompanied by a > characteristic 4-5Hz chirrup when RV251 is turned to the max. > > Where might we go from here, please? > > Cheers, > > Keith > > > > On Wednesday, 26 February 2014, 3:15, Doug McNutt <dougl...@macnauchtan.com> > wrote: > At 18:39 -0800 2/25/14, Peter R wrote: > >Sounds like you might have a short somewhere after the harnesses. > > Yep. Check the solder joints on the connectors that probably got unplugged > during the work. > > I can't prove it but I really believe that the larger solder joints don't get > quite hot enough during the wave soldering operation which has a bunch of > much smaller connections to get right. > > > -- > --> The best programming tool is a soldering iron <-- > > > -- > -- > ----- > You received this message because you are a member of the Vintage Macs group. > The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our > netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml > To post to this group, send email to vintage-macs@googlegroups.com > To leave this group, send email to vintage-macs+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/vintage-macs > > Support for older Macs: http://lowendmac.com/services/ > --- > You received this message because you are subscribed to the Google Groups > "Vintage Macs" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to vintage-macs+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- > -- > ----- > You received this message because you are a member of the Vintage Macs group. > The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our > netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml > To post to this group, send email to vintage-macs@googlegroups.com > To leave this group, send email to vintage-macs+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/vintage-macs > > Support for older Macs: http://lowendmac.com/services/ > --- > You received this message because you are subscribed to the Google Groups > "Vintage Macs" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to vintage-macs+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/groups/opt_out. > > > > -- > Charles > > > > -- > Charles > -- > -- > ----- > You received this message because you are a member of the Vintage Macs group. > The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our > netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml > To post to this group, send email to vintage-macs@googlegroups.com > To leave this group, send email to vintage-macs+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/vintage-macs > > Support for older Macs: http://lowendmac.com/services/ > --- > You received this message because you are subscribed to the Google Groups > "Vintage Macs" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to vintage-macs+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/groups/opt_out. > > > > -- > -- > ----- > You received this message because you are a member of the Vintage Macs group. > The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our > netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml > To post to this group, send email to vintage-macs@googlegroups.com > To leave this group, send email to vintage-macs+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/vintage-macs > > Support for older Macs: http://lowendmac.com/services/ > --- > You received this message because you are subscribed to the Google Groups > "Vintage Macs" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to vintage-macs+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/groups/opt_out. -- -- ----- You received this message because you are a member of the Vintage Macs group. The list FAQ is at http://lowendmac.com/lists/vintagemacs.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to vintage-macs@googlegroups.com To leave this group, send email to vintage-macs+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/vintage-macs Support for older Macs: http://lowendmac.com/services/ --- You received this message because you are subscribed to the Google Groups "Vintage Macs" group. To unsubscribe from this group and stop receiving emails from it, send an email to vintage-macs+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
