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Macintosh Portable M5120 Coil Choke Inductor Pulse replacement
Posted by: macalle69 on 2015-07-13 12:18:01 Hy Everybody someone can help me, i'm not in the position to finding in Italy the same inductor PULSE PE-53082 8946 IP that has been damaged, I can not find the datasheet and I ask to you if you know a replacement part with the same characteristics thank you !!
Posted by: uniserver on 2015-07-13 12:42:47 did you check it with a meter?
Posted by: Ferrix97 on 2015-07-13 13:14:28 Ciao! Why do you think that the inductor is bad? is it open? usually it is very hard to measure inductance with a multimeter. It might lead you to think that the component is shorted. From what I remember, the inductor is part of a DC-DC "Boost"converter circuit, the main chip is a LT1070, looking at its datasheet, it looks like it uses a 150uH axial inductor. At this point, I did a quick search on RS (a large component supplier in Italy), and I found this: PE-52645NL. I am not sure that the PE-53082 is a 150uH inductor, in power supply designs, they usually choose a slightly higher inductance value than the one recommended by the datasheet. Once I get some free time, I will look at Portable Board and I will try to find a similar replacement part. EDIT: maybe this one or this one are suitable replacements, I found this document that lists all of the models from Pulse
Posted by: macalle69 on 2015-07-13 14:22:50 Ciao! Why do you think that the inductor is bad? is it open? usually it is very hard to measure inductance with a multimeter. It might lead you to think that the component is shorted. From what I remember, the inductor is part of a DC-DC "Boost"converter circuit, the main chip is a LT1070, looking at its datasheet, it looks like it uses a 150uH axial inductor. At this point, I did a quick search on RS (a large component supplier in Italy), and I found this: PE-52645NL. I am not sure that the PE-53082 is a 150uH inductor, in power supply designs, they usually choose a slightly higher inductance value than the one recommended by the datasheet. Once I get some free time, I will look at Portable Board and I will try to find a similar replacement part. EDIT: maybe this one or this one are suitable replacements, I found this document that lists all of the models from Pulse Hy Buddies! Very hard to do with Meter, mine is not the best , testing i report these values as in pics attached I've broken inductor legs desoldering it ( don't ask me why i've done it! I'm a real As..hole) Grazie Ferrix i'll get in touch with you in italian ( my english is not so good) ! Thanks Uni for your availability any suggestion about ?
Posted by: macalle69 on 2015-07-13 14:30:05 Ciao! Why do you think that the inductor is bad? is it open? usually it is very hard to measure inductance with a multimeter. It might lead you to think that the component is shorted. From what I remember, the inductor is part of a DC-DC "Boost"converter circuit, the main chip is a LT1070, looking at its datasheet, it looks like it uses a 150uH axial inductor. At this point, I did a quick search on RS (a large component supplier in Italy), and I found this: PE-52645NL. I am not sure that the PE-53082 is a 150uH inductor, in power supply designs, they usually choose a slightly higher inductance value than the one recommended by the datasheet. Once I get some free time, I will look at Portable Board and I will try to find a similar replacement part. EDIT: maybe this one or this one are suitable replacements, I found this document that lists all of the models from Pulse Hi Ferrix have you recapped macintosh portable original ac adapter? I have followed your videos on you tube and repaired 3 powerbooks 100 adapter ( of 5 not working) My Macintosh portable ac adapter is not working stable , now i use an aftermarket 1,5 amp but i'd like to repair the original one maybe the capacitors references are the same .
Posted by: uniserver on 2015-07-13 14:52:51 Ah, i see.. i have an extra i can send you, maybe i can throw it in a parcel back to you?
Posted by: macalle69 on 2015-07-13 15:06:18 Ah, i see.. i have an extra i can send you, maybe i can throw it in a parcel back to you? Keep it! Asap i'm considering to send you some MB to repair thanks UNI
Posted by: uniserver on 2015-07-13 15:10:51 ok sounds good buddy.
Posted by: techknight on 2015-07-13 15:51:11 your meter leads are in the wrong holes!
Posted by: Ferrix97 on 2015-07-14 01:17:04 I have never opened a Macintosh Portable Power Supply (because I don't own one), but I think it is repairable. You can also tweak a PowerBook 100 PSU to work with a portable, there is a current adjustment trimmer inside. I'll send you a PM (in Italian) soon
Posted by: macalle69 on 2015-07-14 04:09:15 your meter leads are in the wrong holes! Hi Techknight thank you , i have tried also in other holes but the only values i registered were those, not the right instrument .
Posted by: techknight on 2015-07-14 04:47:40 You need continuity check. Plus that meter is a piece of crap anyway. You need a good one.
Posted by: MikeatOSX on 2015-07-14 04:56:41 What's a good one?
Posted by: Ferrix97 on 2015-07-14 05:16:25 I usually recommend Fluke Multimeters, but they are quite expensive, about 100€ for an entry level auto-range model. If you are on a budget, you can get a UNI-T or Mastech for less than half the the price of the Fluke. just make sure they are auto-ranging meters. some meters are also able to measure inductors and capacitors, but usually this feature doesn't work that well.
Posted by: MikeatOSX on 2015-07-14 06:29:18 Thanks, good info! I'm also searching for a multimeter with very thin tips to measure the tiny connectors of PRAM batteries.
Posted by: techknight on 2015-07-14 16:51:48 Also another thing that will help here is a B&K Precision or the like LCR meter. that will measure the inductance and the Q rating of the coil. If I am not mistaken, I believe those measured out to be about 150uH.
Posted by: Ferrix97 on 2015-07-15 01:28:09 150uH is the inductance value recommended in the LT1070 datasheet for a 5V to 12V DC-DC Boost Converter They also recommend this inductor, but it is way bigger than the one mounted on the portable. But in the inductor's datasheet, they also specify a "C" size that matches with the size of the inductor in the portable, but they only go up to 100uH
Posted by: uniserver on 2015-07-15 14:07:58 Nice yeah data sheets are a beautiful thing.
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