paryavi@harris.cis.ksu.edu (Saiid Paryavi) (10/02/89)
A while back I posted a request for information about placing a hard disk inside a Mac Plus to make it portable. I received many requests for a summary of the info. So, here it is. By far, the best suggestion was given by Mike: "Hack first, ask questions later." ------------------------------------------------------------------------------- ---------------------------- SUMMARY ------------------------------------------ ------------------------------------------------------------------------------- No, the Mac Plus really shouldn't have a hard drive inside it. The big problem is space and (more importantly) cooling. The convection cooling inside the Plus is bad enough without adding a hard drive. If you want an internal hd, you'd best upgrade to an SE. eric ------------------------------------------------------------------------------- > Does the power supply have enough juice to handle the extra load? Depends on the power requirements of the disk, and on how much memory you have in the box. The power supply is a weak spot in the Plus, 512k, and 128k machines. You should check the power-supply cables, jacks, and pins for signs of overheating or defective solder joints (a common problem); you should also check the power-supply voltage after installing any new equipment, and if necessary adjust it to +5 volts. > Is there room inside the Plus for a hard drive? I believe there's room for a 3.5" half-height drive, if you squeeze it into the proper place. > How will the SCSI connection be made? I believe that the SCSI cable which runs between the logic board and the external SCSI port can be unplugged from the logic board; you'd then plug in a short cable running between the logic board and your internal drive. It might be possible to daisy-chain the SCSI so that you could use both the internal drive and external SCSI peripherals. > Does one need special brackets? Yes. > Is a fan necessary? It's a VERY good idea. > Is there a company that might sell an installation kit or something? Dunno... a quick glance through the back pages of MacWorld didn't turn up _any_ internal drives for the Plus. My impression is that putting an internal drive into a Plus is generally considered to be a Bad Idea, due to the limitations of the power supply, heat, the nonstandard mounting required, etc. Several companies make hard-disk accessories for the Plus which mount on the back of the case... in effect, increasing its depth by a couple of inches (or less). These external-but-tightly-coupled drives contain their own power supply, and plug into the external SCSI port; they require no modification to the Mac itself. Jasmine had/has one of these (the BackPack), and I seem to recall that someone else (Rodime??) was marketing one. Jasmine's versions list for anywhere between $650 (20 megs) and $1300 (100 megs). This sort of drive might be your best bet... it would give you "luggability" (no separate case) and would not overstress your Plus's power supply. Dave ------------------------------------------------------------------------------- I have seen ads for the Jasmine Backpack: Adds about 1 3/4" to the back of the Mac, piggy backs on the scsi port, and (I think) also is powered through teh same power cord as the Mac. No experience with the Backpack; just saw one of their ads. Mike "Hack first, ask questions later." ------------------------------------------------------------------------------- LaCie used to sell kits for SE's. Perhaps they also made a MacPlus version? I think the Plus power supply is NOT powerfull enough, so you need to add another power supply. The original "HyperDrive" for the MAcplus did this. ------------------------------------------------------------------------------- >Does the power supply have enough juice to handle the extra load? No, you will have to figure out how to run off of 120V. >Is there room inside the Plus for a hard drive? Yes, but the packaging is not trivial. You *don't* want any of your additions to work loose, get too close to the high voltage of the CRT, etc. >How will the SCSI connection be made? You will probably want to securely clamp onto the SCSI chip. It leaves fewer marks than the alternatives if you ever need to pull out the addition before sending the Mac in to be repaired. Apple repair people don't like to work on machines which have been modified. You want to be able to remove your work without obvious marks. >Does one need special brackets? Absolutely, you will be on your own. >Is a fan necessary? Another absolutely, the Plus gets hot enough as is. >Is there a company that might sell an installation kit or something? General Computer Corporation used to sell the internal HyperDrive, and Apple even sanctioned it, but they had such trouble that they abandoned it. This was early on, before the Macintosh Plus, when disks were low capacity and delicate--I mean worse than now--but they did give up. They even changed their name to GCC. >I'd like to hear your thoughts on this matter. If there is any >interest, I will summarize and post the responses to the net. Open up your Macintosh Plus and look around. Figure out how you will mount the drive, and whether it will stay there. Figure out what power supply you can find which will fit, and where you will put it. Figure out how you are going to tap onto the SCSI bus. Figure out where and what fan you will use. If you are up to solving these problems, go for it. If they seem like too much or you are not sure about the problems are about, don't do it. Would I consider putting an extra 3-1/2 drive into my Plus? Yes. Have I actually done anything other than consider it? No. Are there better ways? Well, maybe you want an SE? Apple already solved the problems you will face. Or, seeing as how a Plus doesn't travel very well without a carrying case, and most carrying cases will also hold an external disk, it might do as well. Besides, external drives are more flexible than internal drives anyway. Kent ------------------------------------------------------------------------------- I'm not sure if a internal 3 1/2" drive will work in your Mac+. Fitting it in may not be a problem but connecting through the SCSI port may be! The only suggestion I have is looking into the Jasmine BackPac Hard Drive. The drive is available in 20MB to 100MB and attaches to the back of the mac. You only have one power cord since the drive itself plugs into the mac's power inlet and it also has a SCSI port on the drive so you can add other devices. The drive will add about an inch or so to the depth of the mac but it seems to be a good idea in making the mac portable. One word of caution, I've been reading the network a lot about what drives are good and bad and Jasmine has it's share of problems. Maybe if someone who is using a BackPac can respond and tell us if the unit is reliable or not. Anyways, I hope this suggestion is helpful. John -- Saiid Paryavi Computer Science Dept. Internet: paryavi@harris.cis.ksu.edu Nichols Hall BITNET: paryavi@ksuvax1.bitnet Kansas State University UUCP: {rutgers, texbell}!ksuvax1!harry!paryavi Manhattan, KS 66506