To that list, you could add: * Internal nicd battery is dead and being charged rather than merely maintaining/floating at the time
* Any/all the ports could draw a little more from having something actually connected. The barcode, bus, and option rom sockets have actual 5v power supply pins besides just signals, which will have some maximum current they promise to support, or a combined maximum. But also signal lines can draw a little too. It isn't a lot, but there can be a worst-case condition or combination of factors which draws more than average or more than when idle or no device connected. like all bits high on the parallel port and the connected device having low-ohm pull-down resistors, or all bits toggling as fast as it can, etc. * Code that is exercising everything as much as possible, cpu tight loop, writing and re-writing the entire contents of ram continuously, generating signals on all ports, updating the lcd, etc * Current draw goes up as supply voltage goes down. If the power supply is under-voltage, then the same load will draw more current than if it was connected to full 6v. There will be some theoretical worst case where everything possible is maxxed out at the same time, and all the tiny things will add up to be a little more than that 182ma below. Let's say that theoretical max condition is 200ma. For a 200ma actual load you might spec a power supply for twice that, because if you have a power supply that can deliver 200ma, and you load it down with 190ma all the time, the power supply will just run hot and burn out in a short time. Having a power supply capable of more current doesn't hurt. Over-voltage hurts, and under-voltage hurts, as in they both burn out parts in the computer. Under-current doesn't hurt the computer hardware, but the computer will simply run unstable and crash and corrupt data, and will hurt the power supply hardware. Extra current capacity in the power supply just means the ps is not working very hard to supply the load, so it runs cooler and lasts longer and never burns out, also a lightly loaded supply generally maintains a cleaner more stable output with less AC ripple and less dips from changes in the load or changes in the wall power. So ideally you want a 6v supply rated 400ma or more. 400ma is probably already about twice what the theoretical worst case draw is, and so that's why that's what's specced. And you want 6v not 5v, ideally, for a couple different reasons. A 5v supply will need to supply more current, and the first few components in the m100 after the power input will draw more current than usual and thus run hotter and could burn out sooner than they would have (which may still be many years). And if you need 5v for all the internal ttl logic (he said redundantly, like "vin number"), then you need to supply a bit more than 5v to the input of a simple linear regulator. A modern switch-mode supply rated 6v and anything around 400ma or more is fine. 500ma is fine, 2000ma is fine. Even more ma is fine, just pointless. A 1000ma or more supply could be shared and supply several things at once. A M100, TPDD, and CCR-82 tape drive all take the same 6v and all spec 400ma supply or less each, so a 1500ma supply could supply all three at once and still be comfortably over-sized and not over-taxed supplying the actual load. I don't know about a printer. TRP-100 runs on 6v but needs 2000ma all by itself. I like Radio Shack 273-1763 with adapta-plug M. 1800ma, and it's tiny with a long thin wire. Very portable. But you have to find old ones or NOS on ebay. https://ebay.com/itm/401121147466/ Then, with 1800ma on tap, and seeing as both the tape drives and disk drives take the same center-negative 6v plug, you can use a splitter cable to power 2 or 3 devices all from the same tiny wall plug, without soldering or splicing. Go on ebay and search "5.5x2.1mm splitter" https://ebay.com/itm/141110777775/ They also make extensions and right-angle adapter cables, and even polarity-reversing cables. If you had one device that was not center-negative it could still share the same single wall plug. Several of the other common tape drives are 6v center-negative too, same size plug. At least CTR-41, CTR-80, and CCR-81, besides CCR-82. So are all 3 related computers 100, 102, 200, and both TPDD1 and TPDD2 disk drives. So that makes it pretty handy you can use the same power pack on everything. -- bkw On Mon, Jan 13, 2020, 9:37 PM Hank Riley <[email protected]> wrote: > > Related data for the M100 (under 100 mA most often). I'm not sure where I > found this; it could well be from this list's archives. Author was Robert > Briggs, 1987. > > > * Mode 32kRAM 96kRAM* > > * Power Switch OFF .75 mA .75 ma* > * Switch on,POWER OFF 1.60 1.60 * > * Switch on -- MENU 62 96 * > * TELCOM 88N1D 60 94 * > * TELCOM M7I1E(Modem) 147 182 * > * Cassette on/SOUND ON 110 140 * > * Cassette on/SOUND OFF 108 137 * > * Bar Code Wand On 109-114 157-170* > * Printer OFF 72 116 * > * Printer ON 63 107 * > * R/S Disk Drive 61 100 * > > > > On Monday, January 13, 2020, 07:14:19 PM EST, Josh Malone < > [email protected]> wrote: > > In practice, the 102 won't draw anywhere near 400mA under most > circumstances. Just about any DC battery pack rated in the 6v range will do > the job. If you feel like adding a fast blow fuse, more power to you. >
