Hello Tom, I may not have caught all that went in the thread, did anyone mention this already?
Powerswitch Tail - $25 https://www.adafruit.com/products/268 I like it because it is self-contained — I am all for hacking, but setting a house on fire is not the cool part of hacking. So, when using more than 18V, I do like things that come properly packaged…. cheaper than having them installed by a certified electrician, anyway :) When using relays, one still must take care not to overload the circuit — it is rating for some top load that, I am sure, is not adequate to start your dryer remotely. Just saying. Best -F On Nov 12, 2012, at 2:22 PM, Tom Metro wrote: > Jack Coats wrote: >> http://www.fullcompass.com/product/366255.html?utm_source=googleps&utm_medium=shopping&utm_campaign=googleps&gclid=CKSL0re7xLMCFao7MgodIWcA7Q >> -- Interesting device for controlling and monitoring 2 audio lines in >> and out. USB controlled and powered for $30 > > This is a USB sound card, much like hundreds of others, although it > claims to use 48-bit converters, which is a bit different. > > In any case, not particularly relevant to the question at hand. > > >> http://procontrol.com/products/pro-relay-4/ -- professional looking, 4 >> relay, ethernet or IR interface, POE or 1A 12V external power, no >> price on page at first glance > > Looks like it is aimed at high-end home automation and home theater > integrators. Probably not priced to be hacker friendly. > > >> http://www.sigma-shop.com/product/7/usb-relay-controller-one-channel-box.html?&CurrencyID=1 >> -- 1 relay, USB controlled, nicely packaged > > Agreed, nicely packaged. USB-B connector on one side. 3 screw terminals > for form-C relay contacts on the other. No relay specs provided. > Emulates a serial port. $30. > > >> http://numato.com/2-channel-usb-relay-module -- 2 relay, USB >> controlled, board with exposed components assembled > > No case, but you get two relays here. The down side to this one is that > they require you attach a 12V supply (not included) to power the relays. > (Discussion thread below the product info indicates the vendor is > working on a version that is fully USB powered.) > > The product description says the relays can handle 10 A, but the manual > cautions that for anything over 2 A they recommend you thicken up the > PCB traces to the relay contacts with solder. They might have well just > used low-current reed relays, and kept it USB powered. > > Nowhere do they mention what the voltage rating is on the relay. While > most relays will handle 120 V, some don't have adequate contact spacing, > so you can't just assume. I have a feeling they left off this spec to > avoid any liability for inadequate high voltage isolation and lack of UL > approval. (All of this applies to the other relay product above, as well.) > > This device also emulates a serial port. The command language they > designed seems rather clumsy, but adequate. > > The manual says, "On board ICSP header makes it easy to be used as a > development system as well." What's an ICSP header? (Aside from being a > 6-pin header?) Ah...In-circuit serial programming: > http://en.wikipedia.org/wiki/In_Circuit_Serial_Programming_%28ICSP%29 > > Not sure how that applies to this device. There's no indication that you > can reprogram the micro on the board. Are they using it like an I2C > interface? Based on the Wikipedia page, it looks like it is only used > for programming, so I guess the intent is that hackers can customize the > firmware. > > > Thanks for digging these up. I have a bookmark folder full of serial and > USB controlled relay products. Others include: > > http://www.j-works.com/jsb315.php > http://canakit.amazonwebstore.com/CanaKit-4Port-USB-Relay-Controller-with/M/B004JWW1GQ.htm > > They're both more expensive than the ones you found. > > >> Now $30 isn't cheap (under $2 is in my book), but these options are >> not bad for $30 equipment. > > Agreed. > > >> Tell us what you choose, and how it works for you in your application. > > I'm still in the mood to build something, so I'm pursuing that avenue. > But I've saved the above for future reference. > > I found one of my solderless breadboards that I haven't used in a long > time, and the parts with it - a DB25 with some 22 AWG solid wire leads > soldered on, and some optocouplers - suggests my last project with it > was another parallel port interfacing project. > > >> I use an earlier version of http://www.digital-loggers.com/lpc.html >> that cost about $130. > > Yes, you wrote about that on the list before as part of the PC watchdog > thread. I never did get the Trip Lite UPS with built-in watchdog reverse > engineered. The device I was planning to use it on worked with adequate > reliability on a simple timer that forced a daily power cycle, so I > didn't have adequate motivate to spend the time on it. Maybe someday, as > it would be nice to have a $40 UPS that includes a watchdog that's > supported by Linux. > > -Tom > > _______________________________________________ > Hardwarehacking mailing list > [email protected] > http://lists.blu.org/mailman/listinfo/hardwarehacking _________________________________________ -- "'Problem' is a bleak word for challenge" - Richard Fish (Federico L. Lucifredi) - flucifredi at acm.org - GnuPG 0x4A73884C _______________________________________________ Hardwarehacking mailing list [email protected] http://lists.blu.org/mailman/listinfo/hardwarehacking
