From jwbruce at ece.msstate.edu Tue Feb 10 12:35:24 2009 From: jwbruce at ece.msstate.edu (J. W. Bruce) Date: Tue Feb 10 12:35:28 2009 Subject: [ece1002] soldering instruction In-Reply-To: <14898489.572701234290538685.JavaMail.root@zimbra.ece.msstate.edu> Message-ID: <3646454.572751234290924927.JavaMail.root@zimbra.ece.msstate.edu> We will be starting our soldering instruction in ECE1002 on MONDAY, Feb. 16th. You will need to bring your soldering irons to class on that day. You will also find it useful to have a tool or tools to strip insulation (16AWG and smaller) and cut wires. A pair of small needle nose pliers would also be very useful. You should be able to buy these things almost anywhere reasonable: Lowe's, Wal-mart, Radio Shack. Even Fred's, Dollar Tree, CVS and Krogers have them, but of lower quality. The soldering parts kit will be available after class tomorrow. The cost is $10 even. CASH ONLY. Try to bring a $10 bill or two $5s so we do not have to make change. The soldering kits will also be available before class on Monday. Every student must purchase their own soldering parts kit. You will submit your completed soldering for a grade. See you. jwb ------------------ J.W. Bruce, Ph.D., Associate Professor Department of Electrical and Computer Engineering Mississippi State University 406 Hardy Road, Simrall 335 Mississippi State, MS 39762-9571 Office: (662) 325-1530 FAX: (662) 325-2298 From jwbruce at ece.msstate.edu Tue Feb 17 09:55:20 2009 From: jwbruce at ece.msstate.edu (J. W. Bruce) Date: Tue Feb 17 09:56:01 2009 Subject: [ece1002] Re: [ece1002-01] soldering instruction In-Reply-To: <14847814.605711234884945202.JavaMail.root@zimbra.ece.msstate.edu> Message-ID: <1326264.605901234886120617.JavaMail.root@zimbra.ece.msstate.edu> ----- Original Message ----- > To: "J. W. Bruce" > Sent: Monday, February 16, 2009 10:35:02 PM GMT -06:00 US/Canada Central > Subject: Re: [ece1002-01] [ece1002] soldering instruction > > Where would you expect students to complete their > soldering? In the dorm rooms? Back in room 308 > at any time? The point of having your own equipment is that you can do your work wherever you choose. You can solder at home; I've done it many times. Just take extra care if you have children or pets around. You may want to spread something over your mahagony dining room table to protect it from burns or solder spatter. * Don't use something flammable! Old sheets or newspaper are very bad ideas. A big glass or ceramic platter is great. A cutting board works nicely too. Just do NOT use these things for eating EVER AGAIN! Another good place to solder at home is on the back patio. The weather can be quite nice this time of year; you get lots of good ventilation outside. Plus, it requires a special talent to catch concrete on fire! * Don't do anything to lose your security deposit! Otherwise, you may use the labs in Simrall. But, be mindful of the labs that are scheduled for those rooms. You can use an unoccupied chair during a scheduled lab, but be unobtrusive and let the TA know what you are doing. If a lab seat is need by a scheduled lab student, then you will need to move on. * No matter where your work, leave your workspace cleaner than you found it. This is just old- fashioned professional courtesy. JWB PS: Be sure your clean and tin your soldering iron tips often and regularly. This is especially important with a new iron. Irons are a bit like cast-iron cookware. The tips will "season" with use and require less vigilant care, while giving better and better results. My iron practically tins itself nowadays. ------------------ J.W. Bruce, Ph.D., Associate Professor Department of Electrical and Computer Engineering Mississippi State University 406 Hardy Road, Simrall 335 Mississippi State, MS 39762-9571 Office: (662) 325-1530 FAX: (662) 325-2298 From jwbruce at ece.msstate.edu Tue Feb 17 10:23:43 2009 From: jwbruce at ece.msstate.edu (J. W. Bruce) Date: Tue Feb 17 10:23:50 2009 Subject: [ece1002] soldering safety In-Reply-To: <19057033.606021234887564112.JavaMail.root@zimbra.ece.msstate.edu> Message-ID: <6632778.606151234887823138.JavaMail.root@zimbra.ece.msstate.edu> After a couple of questions yesterday, I thought I would address soldering safety. Soldering is done by tens of thousands of people everyday. It is very safe if you use common sense. Smoking a single cigarette is far more harmful to your body than an entire afternoon of soldering. PCB manufacturing, chip-stuffing, and soldering do involve some nasty chemicals. In general, your soldering kit has omitted the worst offenders. In fact, we don't even stock some of the common (nasty) soldering chemicals in Simrall anymore, even for use in our research programs. The hazmat regulations from EPA and OSHA were too expensive, so we disposed of them and use alternative means. In general, pregnant women are encouraged NOT to solder. Mostly due to the remote chance of lead poisoning to the fetus. Your kit has no-lead solder so this danger is gone. Even with leaded solder (I use leaded solder), you would get very little lead exposure in ECE 1002 as your total soldering time in ECE 1002 (~8 hours max) is probably less than a manufacturing tech would spend soldering in a typical workday. Rules are simple: Don't ingest solder Don't inhale any by-products of soldering Minimize skin contact with anything nasty, and Thoroughly wash your hands/clothes afterwards. Then: no problems! Engineers need to know how to solder to build the occasional prototype and to understand the limitations of manufacturing. In practice, engineers do not do a great deal of soldering. That is left to the workers in the manufacturing facility. The biggest danger to you in soldering in ECE 1002 is the chance of a nasty burn. If you have a specific concern about safety or the affects to you personally, contact me. We can meet and talk about it. JWB ------------------ J.W. Bruce, Ph.D., Associate Professor Department of Electrical and Computer Engineering Mississippi State University 406 Hardy Road, Simrall 335 Mississippi State, MS 39762-9571 Office: (662) 325-1530 FAX: (662) 325-2298 From jwbruce at ece.msstate.edu Tue Feb 17 11:07:31 2009 From: jwbruce at ece.msstate.edu (J. W. Bruce) Date: Tue Feb 17 11:07:41 2009 Subject: [ece1002] more soldering In-Reply-To: <12866808.606641234890297605.JavaMail.root@zimbra.ece.msstate.edu> Message-ID: <4399904.606661234890451852.JavaMail.root@zimbra.ece.msstate.edu> If you want more soldering hints, Expert Village has a few videos. Try these videos. You can search Expert Village for some more..... Soldering Safety.... This guys looks a little bit like Mike Nosser! http://www.expertvillage.com/video/49416_soldering-safety.htm Basic skills http://www.expertvillage.com/video/4890_electronic-circuit-tinning-iron.htm http://www.expertvillage.com/video/31175_repair-cables-solder-iron.htm http://www.expertvillage.com/video/4918_electronic-circuit-reflowing-connection.htm http://www.expertvillage.com/video/4915_electronic-circuits-solder-connections.htm Using solder wick/braid: http://www.expertvillage.com/video/49419_soldering-wic.htm In this one, Ross uses a manual "solder-sucker" to desolder. My solder- sucker is electric. Regardless, you must use the solder wick/braid to remove the majority of solder first..... http://www.expertvillage.com/video/4909_electronic-circuit-desoldering.htm In this one, you can how "helping hands" are really useful. http://www.expertvillage.com/video/4897_electronic-circuit-solder-lead.htm Check out his homemade wire-holding jig in this video.... I wish I had one of these! http://www.expertvillage.com/video/31178_repair-cables-prepare-wires.htm Here's a really good video from YouTube: http://www.youtube.com/watch?v=I_NU2ruzyc4 This video wins the award for the NASTIEST iron. It's too big to boot. I also strongly discourage "flicking" solder off... very dangerous. http://www.youtube.com/watch?v=BLfXXRfRIzY Finally, there is tons of "bad form" in this video, but you might aspire to be one of these athletes someday: http://www.youtube.com/watch?v=-gFJ2QfQcb4 ------------------ J.W. Bruce, Ph.D., Associate Professor Department of Electrical and Computer Engineering Mississippi State University 406 Hardy Road, Simrall 335 Mississippi State, MS 39762-9571 Office: (662) 325-1530 FAX: (662) 325-2298 From jwbruce at ece.msstate.edu Thu Feb 19 10:02:15 2009 From: jwbruce at ece.msstate.edu (J. W. Bruce) Date: Thu Feb 19 10:02:18 2009 Subject: [ece1002] schematic error In-Reply-To: <17567202.623851235059264630.JavaMail.root@zimbra.ece.msstate.edu> Message-ID: <12034274.623871235059335619.JavaMail.root@zimbra.ece.msstate.edu> The schematic on page 8 of your SP-3B instruction manual has an error. At the bottom of the page, R18 should be 100k R17 should be 120k R20 should be 470k R19 should be 680k If you have already soldered these resistors in, it won't make a big difference: The resistance checks at the bottom of page 11 will not be correct. JWB ------------------ J.W. Bruce, Ph.D., Associate Professor Department of Electrical and Computer Engineering Mississippi State University 406 Hardy Road, Simrall 335 Mississippi State, MS 39762-9571 Office: (662) 325-1530 FAX: (662) 325-2298 From jwbruce at ece.msstate.edu Fri Feb 20 13:36:23 2009 From: jwbruce at ece.msstate.edu (J. W. Bruce) Date: Fri Feb 20 13:36:27 2009 Subject: [ece1002] more soldering tips In-Reply-To: <31056266.628321235158475387.JavaMail.root@zimbra.ece.msstate.edu> Message-ID: <22609519.628341235158583797.JavaMail.root@zimbra.ece.msstate.edu> As you finish your PCB, here are two more useful tips gleaned from years of experience: * When soldering anything rectangular (like the 16-pin socket U1), place the device in/on the PCB. Solder WITH THE ABSOLUTE MINIMUM AMOUNT OF SOLDER the pin #1, usually at the top left. Use just enough solder to keep the little part from falling off. We will redress this pin later... With that one pin "tacked" down, you can gently pivot the device to get perfect alignment with the PCB holes/pads. With the device perfectly placed, solder the OPPOSITE CORNER pin (pin #9 at the bottom right in our case). Now the device can't move and should be just perfect. Solder the remaining pins. Go back and reflow the first pin to relieve the mechanical stress induced by pivoting the part at the beginning. Add more solder to pin #1 to bring it up to snuff. * When attaching "flying" leads like the battery connector to your PCB, you must provide some mechanical strain relief. Our SP-3B PCB has a hole next to the battery solder point to pull the battery leads through. This helps, but you can go one step further to keep from yanking your battery leads off the board with rough handling. (You will have to desolder your battery leads to do this, but I highly recommend it). Pull your battery leads through the hole next to the switch. The lead ends should be on the component side with the battery clip on the solder side. Go back about 1cm from the lead ENDs, take the pair of leads and tie a simple knot so that the ENDs can't slip back through the hole. Now, turn the board over. Take the battery clip end and tie another knot on the solder side of the PCB. Slip the two knots toward each other until they rest on their respective side of the PCB just a couple mm away from each other. Now the battery leads should have very little play as it slips through the hole in the PCB. Now, solder the battery leads to the PCB. Now, yanking on the battery itself will impart nearly ZERO force on the very delicate solder joints! Cool, huh? ------------------ J.W. Bruce, Ph.D., Associate Professor Department of Electrical and Computer Engineering Mississippi State University 406 Hardy Road, Simrall 335 Mississippi State, MS 39762-9571 Office: (662) 325-1530 FAX: (662) 325-2298 From jwbruce at ece.msstate.edu Mon Feb 23 12:05:01 2009 From: jwbruce at ece.msstate.edu (J. W. Bruce) Date: Mon Feb 23 12:05:19 2009 Subject: [ece1002] Amateur (ham) radio exam THURSDAY 7PM In-Reply-To: <18075420.633311235411956770.JavaMail.root@zimbra.ece.msstate.edu> Message-ID: <25781747.633331235412301092.JavaMail.root@zimbra.ece.msstate.edu> W5YD, Mississippi State University's historic Amateur Radio Club, will be hosting an exam session for FCC amateur radio licensing on Thursday (February 26th) at 7PM. The exam will be hosted in the Simrall Electrical & Computer Engineering Building rooms 102 and/or 104. The Simrall Building is typically locked at night, so people will need to enter through the main lobby entrance. We'll post a doorman there to let people in. The following items are MANDATORY. There will be NO EXCEPTIONS! Bring to the test session: 1. $15 __CASH__ in correct change (No checks, $20's etc. We can't make change.) 2. A photo ID or 2 non-photo ID's 3. The original and a copy of your license (if you have one). 4. The original and a copy of any current CSCE's (if you have any) If you need some last-minute study aids or practice exams, surf over to http://w5yd.org.msstate.edu/new_site/license.php MFJ (located on Industrial Blvd) also sells study guides. If you want more info about W5YD and/or amateur radio, please contact Jarrod Marsh, W5YD president, at jcm177@msstate.edu. Also, if you plan on taking an exam on Thursday, please let Jarrod know so he can have your exam prepared. Thanks, JW BRUCE (AE5GO) Faculty Adviser, W5YD Amateur Radio Club PS: W5YD members will be monitoring the W5YD 2m repeater (146.805-) Thursday evening if you need assistance or directions. Feel free to check in on the repeater as you make your way to the building. ------------------ J.W. Bruce, Ph.D., Associate Professor Department of Electrical and Computer Engineering Mississippi State University 406 Hardy Road, Simrall 335 Mississippi State, MS 39762-9571 Office: (662) 325-1530 FAX: (662) 325-2298