leo@duttnph.tudelft.nl (Leo Breebaart) (02/20/91)
A few days ago the PowerKey device was recommended here. I am thinking of buying one for my SE/30, but I am a complete electrical novice and am wondering if the thing can be used for a 220V/50Hz environment. (As you may have noticed from my name and my path: I live in the Netherlands.) Can anybody enlighten me? -- Leo Breebaart (leo @ duttnph.tudelft.nl)
leo@duttnph.tudelft.nl (Leo Breebaart) (02/25/91)
Last week, I wrote: > A few days ago the PowerKey device was recommended here. I am thinking > of buying one for my SE/30, but I am a complete electrical novice and > am wondering if the thing can be used for a 220V/50Hz environment. Some time later I received the following reply from Alan Cooney, who cannot post to the net himself, and asked me to do it for him. ----- Here begins Alan's article ----- I've been using a PowerKey with my SE/30 for a couple of months now, and I really love it. Your question intrigued me, so I called Sophisticated Circuits Inc., in Washington, and asked them what they'd recommend for you. The engineer I spoke with says he has sold lots of PowerKeys to European customers with the understanding that they have to use a 220:110 step down transformer to power the unit. To help you understand your options, let me explain what the PowerKey is and how it works: It has a 120Vac line cord attached, four relay-controlled (also filtered/ de-spiked) ac outlets, and a 15 amp circuit breaker. The unit has a six foot (roughly 1.8m) ADB cable with a combination ADB plug/jack at one end so you don't lose an ADB port (the dual jack also serves another purpose for SE users: the jack pin used for the "power up" button on ADB keyboards isn't connected internally on the SEs, and so the PowerKey wouldn't receive the power command if it were plugged into a different ADB port than the keyboard -- in other words, SE users *must* plug their keyboards into the jack of the plug/jack combination for their PowerKey to work -- users of the II series machines should be ok with any configuration, as their machines have all ADB pins connected). PowerKey contains a MicroChips PIC16 processor which handles not only ADB communications, but has a real-time clock in firmware which uses the ac line frequency as its reference. More on that later. Pressing the power request key on your ADB keyboard pulls the "power request" pin of the ADB connector low. PowerKey senses this and waits a prescribed debounce interval to be sure you actually pressed the key (rather than it being a random noise pulse), and then energizes a relay to provide power simultaneously to all four outlets on the unit. This thing would be great even for Mac II owners, as it'll power their peripherals at the touch of the same key that energizes their Mac. When you select "shut down" from the Finder, a PowerKey CDEV intercepts the command and sends a powerdown signal over ADB to the PowerKey hardware unit. It then responds to the command by killing power to all four outlets. The inclusion of a real time clock in the PowerKey unit is an attractive feature in itself. A CDEV user interface allows you to set PowerKey to turn your Mac system on or off at a prescribed time. A menu offers schedules of "once only", "daily", "weekdays", "weekly", or "monthly". When you set a turn-on schedule from the CDEV, it sends that schedule over ADB to the PowerKey device. The PowerKey's clock is set to match your Mac's internal clock via code also sent to it over ADB. PowerKey will adhere to the set schedule(s) as long as a power failure doesn't cause it to lose its memory. In addition, you can have the CDEV simulate pressing a key combination at any time. To take full advantage of this, a simplified version of QuicKeys, called "QuicKeys Lite" ships with the PowerKey. By having the CDEV imitate a key combination that selects a macro, you could have PowerKey switch on your system late at night, and initiate a backup process or file downloading (while the phone rates are low). You can also use the CDEV's timed "keypress" to initiate an unattended shut down. The salesman where I bought mine says he uses it to automatically switch on his Mac at the office just before he arrives each morning, and shut it down just after quitting time. That way he never forgets and leaves his Mac on all night. Another friend uses it to shut down his system each morning at 2 am to keep him from playing on his Mac until dawn :-) Although I find the timer feature a neat idea that may be quite useful to some people, I personally have yet to really *need* it. As the PowerKey's clock is derived from the line frequency, it's timed power-on operation wouldn't be useful to you unless you were willing to do some calculations to compensate for the 17% or so frequency difference in your 50Hz environment. If you use a 220:110 step down transformer to supply power to the PowerKey, you'd be able to plug in your Mac and likely any peripherals designed for the U.S. domestic market. A step up transformer could be used on the output of the PowerKey to run European devices, or you could connect a 110Vac relay to one of the PowerKey outlets, and then switch your 220V equipment with its contacts. The engineer at Sophisticated Circuits said that they're currently talking with a British company about a European marketing deal. As the U.S. version is constructed very compactly, a new case would have to be designed to fit the much larger European mains outlets. He said the major problem there is the enormous costs involved in making the tooling for the plastic molds (the unit has a very tough and attractively designed injection-molded case). They're not likely to reach an agreement for at least a month, and he expects it would then take another five or six months before a "Euro-PowerKey" would ship. This, of course, assumes they *did* reach an agreement. I wouldn't hold my breath. In addition to the PowerKey, Sophisticated Circuits offers a tiny box that will turn your computer equipment on when the phone rings (I saw this at the Mac show in San Francisco). This could be very useful for remote control or access to your Mac from afar without having to leave it on all the time. It works by detecting the ring signal and grounding the ADB power request line to activate a PowerKey or any Mac II. Should you decide to buy a PowerKey, the outlet "Mac's Place" here in the U.S. (800-367-4222 from U.S.or Canadian phones, or 206-883-8312 from locations abroad) has them for $64 (not inclusive of shipping), and has the ring detecting "wake-up cable" for $34. I always felt sort of gypped by Apple for not getting a functional power request key, even though the SE/30 is really just a Mac II in a small box. Heck, we even get the pleasant Mac II chime on power up! The PowerKey makes life a little more convenient, since my Mac, printer, modem, and external drive all come on when I touch the button Apple put on my keyboard for that purpose. Although my apparent praise of this product may make it seem otherwise, I am *not* in any way affiliated with Sophisticated Circuits Inc. I *am* an enthusiastic EE student who believes good designs deserve high praise, and the PowerKey has proven itself to be a *very* good design. ----- Here ends Alan's article ----- I would like to publicly thank Alan for his trouble: I think it was pretty neat of him to call Sophisticated Circuits, and then type the whole thing in, just to answer a question from a total stranger... -- Leo Breebaart (leo @ duttnph.tudelft.nl)
davisson@milton.u.washington.edu (Gordon Davisson) (03/09/91)
In article <leo.667489719@galaxy> leo@duttnph.tudelft.nl (Leo Breebaart) quotes Alan Cooney about using PowerKeys outside the USA: >Although my apparent praise of this product may make it seem otherwise, I am >*not* in any way affiliated with Sophisticated Circuits Inc. I *am* an >enthusiastic EE student who believes good designs deserve high praise, and >the PowerKey has proven itself to be a *very* good design. I forwarded your message to some friends who work for SCI, and they'd like to thank you for your praise. They had, however, one minor correction: >As the PowerKey's clock is derived from the line frequency, it's timed >power-on operation wouldn't be useful to you unless you were willing to do >some calculations to compensate for the 17% or so frequency difference in >your 50Hz environment. This isn't a problem. The software that comes with the PowerKey times the PowerKey's clock against the Mac's, figures out whether the line frequency is 50 or 60Hz, and compensates automatically. (If it's not one of the two, *then* you'll have this problem.) -- Gordon Davisson Westwind Computing (206) 632-8141 4518 University Way NE, Suite 313, Seattle WA 98105