+++++++++++++++++++++++++ See also "Gary_Ss_Build_Tips" ++++++++++++++++++++ NOTE: See "Building_Desoldering_Notes" file also +++++++++++++++++++++++++ Extracted from one of Gary's Responses -------------- Hi, The most important thing IMHO, is to solder as well as possible and tin those toroid leads! Try to make your PCBs look like commercially wave-soldered boards. To many people do not put the effort into soldering the kits they should. This is a very important process, so don't rush through building the kit. I see more kit failures due to poor soldering and PTTL than any other reason. It accounts for probably 90-95% of all problems with the kits. Tom Hammond N0SS has written an excellent soldering tutorial that everyone should read: http://www.elecraft.com/TechNotes/tech_notes.htm It seems from the kits I work on here, that many people use way too much solder and do not heat the connections long enough to flow the solder and remove the flux. This results in cold solder joints, and excessive flux on the PCBs. Use as little solder as required to just fill the connection flush or form a small fillet of solder around the lead. See N0SS's photos. Don't build for too long at one time, or stay up until the wee hours of the morning! :-) 73, Gary Surrency AB7MY support at elecraft.com (Use this address for all official tech support questions, please). ++++++++++++++++++++++++++ Date: Wed, 2 May 2001 23:40:56 -0700 From: "Ron D'Eau Claire" Subject: RE: [Elecraft] pin identification and transistor heating Haines Brown asked: "...I'm being let down by the fact that my practical electronics assembly experience derives from pre-transistor days....don't know how to count the pins on ICs...I'm paranoid about heat when soldering them in. I try to keep the transistors about 1/8" away from the board and am managing to do a solder connection in a second or two...." You aren't alone, Haines. I built my first radio using a 250 watt soldering iron to assemble the circuit around three type 76 triodes. The only concern about heat was to avoid melting all the wax out of the paper capacitors... each one of which was nearly as big as the optical encoder in the K2. First, yes on the IC's. The diagrams in the Elecraft manual show how the pin count goes. It is as you said. And, yes, I had to go look once again to be sure it is there because it still isn't as automatic for me as counting the pins on a tube socket clockwise from the key. . Transistor are a LOT more rugged than they were in the 50's. Not only did we spend $10 for a single transistor that wasn't half as good as a 10 cent 2N2222 is today, today's solid state devices are designed to be hit with molten solder. The point is to limit the total number of calories of heat you pump into them. They take a good splash of hot solder for a couple of seconds just fine. Many commercial boards are soldered by 'wave' machines that actually run a wave of molten solder against the bottom of the board. The problem with hand assembly most often comes with using too COOL of an iron and trying to hold it there for a while to 'heat' the junction. By the time the lead and solder pad get hot enough to solder, you've turned the inside of the device to charcoal. The other extreme is using an uncontrolled temperature iron with too large of a tip. The whole thing gets too hot, and when you make good thermal connection to the lead, all the calories stored up in that fat, hot tip pour into the transistor before the solder has time to melt. A temperature controlled soldering station is a good investment. I use a simple grounded tip soldering iron that is uncontrolled, but I have developed the knack of testing the tip temperature on a wet sponge before attacking the joint. With a small mass tip, it's easy to adjust the temperature that way. For me it was a matter of survival. For years I repaired modern boards with surface mount parts and old gear filled with vacuum tubes on ships with nothing but a Porta-A-Sol butane soldering iron. Use enough heat to solder the joint in 1 or 2 seconds and you are fine. Whether you are using a temp controlled iron or not, if it has a small tip and you can solder in 3 seconds or less your solid state devices should be very safe. The problem with trying to attach heat sinks to the transistor leads is that you leave too much lead exposed in most cases. That will lead to problems with coupling between circuits that will drive you batty. Forget the alligator clips and the fancy flat-tipped heat sink clips designed to protect that transistor from 1950. Mount the transistors just as the manual says and then get them soldered in the 1-2-3 method. Counting slowly, 1 you put the heat on, 2 the solder melts and 3 you are off with the iron. About 2 or 3 seconds of heat total. One thing I did that was not according to the assembly manual was to put in the parts ONE at a time and solder them. I found it easier to do a good job soldering, easier to be sure that I had the right part and had it oriented correctly, and I found it easier to be sure every part was positioned properly against the board when I soldered it. It took longer, but no one was complaining about my taking extra time like they used to do on ships . Ron AC7AC K2 # 1289 ++++++++++++++++++++++++++++++++++ Date: Thu, 3 May 2001 07:31:43 -0400 From: "Don Wilhelm" Subject: Re: [Elecraft] pin identification and transistor heating Haines, IC pin counting proceeds from pin 1 (usually marked with a dot - on the left side of the end with the notch when viewed from the top) goes down the left side of the DIP, then wraps around the end and continues up the other side. Saying it another way, the highest numbered pin is straight across the DIP from pin 1. For transistors, most have the BCE straight line configuration, but there are about 5 different basing diagrams It is best to consult the diagrams to be sure. The ARRL Handbook has good basing diagrams in its Component Data section and there are many other publications with this information. I think your soldering technique may be just fine if you can get a good soldered joint in 2 seconds. Use a sufficiently hot iron so you can get in, get soldered and then get the heat off the joint. The thing that will hurt solid state devices is letting them 'heat-soak', and that will happen if the soldering iron is too cold. OTOH, if the iron is too hot, you will tend to lift PC board traces. I usually use an iron temperature of 650 to 680 degrees with success here, and I usually apply the iron first to the PC board to warm it (close to but not right on the component lead), then feed in a bit of solder and quickly slide the iron up against the wire sticking through the hole - as soon as the solder flows around the component lead, I am done and I remove the iron. If you find yourself lingering with the iron on the joint for longer than 3 seconds, you might worry about potential damage to the component. A soldering tip that is too cold can damage components! 73, Don Wilhelm -Chapel Hill, NC W3FPR home page: http://www.qsl.net/w3fpr/ QRP-L # 485 K2 SN 0020 mailto: w3fpr at arrl.net +++++++++++++++++++++++++++++++++++++++++++++++++ Date: Thu, 03 May 2001 07:59:05 -0700 From: Vic Rosenthal Subject: Re: [Elecraft] balanced tuner Julian wrote: > > Not only do I dislike doing metalwork, I seem incapable of making > the holes in exactly the right place, no matter how carefully I try to do > them. A little off subject, perhaps, but here's how: 1) Always use a center punch. Be sure to solidly back up the material being punched. I find the automatic type is easiest to use. 2) If you have a drill press, congratulations. If not, the trick is to hold the drill vertically. This takes some practice, but is necessary for using a handheld drill. 3) For holes 1/4" (8mm) or larger, drill a smaller pilot hole first. The pilot hole should be about the size of the 'edge' that appears at the point of the larger drill. 4) Use sharp drill bits. Sharpening them by hand against a grinding wheel is an art, so unless you have the time to become an artist buy a good sharpening machine (expensive) or new bits. 73, Vic, K2VCO Fresno CA +++++++++++++++++++++++++++++++++++++++++++++ Date: Thu, 3 May 2001 15:50:22 -0500 From: "Stuart Rohre" Subject: Re: [Elecraft] balanced tuner Vic makes several good points, and I will add my own hints. I make a paper layout on cross hatch squares paper. Thus, I know where all the holes to be drilled go relative to the edges of the metal by taping this pattern over the panel before center punching each drill hole right thru the paper with the Automatic Center Punch. Be sure to dial up enough spring tension, that when the punch fires, you make a big enough dent in the metal to hold the drill bit centered in subsequent drilling. Now there are low cost drill stands to hold a hand drill as a drill press for panel work. Sears and others carry them. Another trick is to see if the drill you have has a bubble level on the back end of the motor, such that when it is absolutely vertical, and thus so is the drill bit, the bubble is centered in the circle and you hold the drill to maintain that until the hole is finished. Another thing is to drill a pilot hole with small bit, and then go with the full size of the hole in the bit for final drilling. Be sure to use sharp bits, and resharpen them on an accurate gauge or buy new ones when needed. Special angles can be ground for drilling thin aluminum, but this is for those who really know how to sharpen bits. A deburring tool that has a greater than 90 degree angle point, that spins in the handle is convenient for cleaning the edges of the holes. These usually come with two bits, one for deburring inside, such as a hole into a box, and one for outside work. I have seen bubble levels for sale at larger hardware or industrial bolt and screw and tool companies that can be glued onto a drill motor that did not come equipped with one. Metal work is no harder than simple woodwork, once you have an understanding of layout and use the right tools. 73, Stuart K5KVH +++++++++++++++++++++++++++++++++++++++++++ Date: Thu, 03 May 2001 21:35:13 -0400 From: "Dave, KB2TQX" Subject: Re: [Elecraft] balanced tuner The Cobra brand Uni-bits are very useful tools when it comes to drilling this sheet metal. You can get them at Home Depot and other good hardware stores. They take all the anguish out of drilling relatively large holes in thin metal. One drill bit about 7 hole sizes. 72/3, Dave KB2TQX ++++++++++++++++++++++++++++++++++++++++++ Date: Fri, 4 May 2001 10:40:11 -0400 From: Tim ORourke Subject: [Elecraft] Drilling Aluminum Drill thin soft aluminum as found on most radio enclosures can be frustrating. I am a tool maker make my own bits that drill round and burr free holes, but you can get close with fish tail wood drills. Wood bits will work in aluminum if run on slow speed, 800-500 RPM should be OK. Use a center punch to locate hole, drill a very small diameter hole , 1/16 or less with conventional bit, then use a fish tail bit of final size to complete. Use cutting fluid, stick lube or plain water. The fish tail drill or one you sharpen your self will cut on the outside edge of bit first and cut through panel on this outside edge first leaving a burr free hole without wallowing out panel. A conventional bit has too much angle, typically 118 to 130 degrees, the point will break through panel before the outer diameter causing odd shaped hole. An alternative is step drills panel bits. They come in many sizes, have multiple diameters, and a are made to cut cleanly in thin stock, downer is they are expensive, and larger ones still need a clean pilot hole. You can find step bits at electrical supply houses or industrial supply houses. Tim O'Rourke KG4CHX ++++++++++++++++++++++++++++++++++ Date: Fri, 4 May 2001 13:02:23 -0700 From: Gary L Surrency Subject: [Elecraft] Warning! No PCB drilling, please! Hello kit builders, A number of kits I have serviced recently have shown signs of the PCB pads being DRILLED! Please, do not do this!!!!! This is very difficult to repair, and adds a lot of extra time, work, and cost to the servicing of the kits. Drilling the PCB pads will destroy the feedthrough connections (vias) that are used at many places on the PCBs to make connections between the top and bottom traces. Use a proper desoldering tool to remove solder from the pads if you need to, or push out the molten solder with a pin or similar tool. Edsyn makes an excellent pump-type desoldering vacuum tool that will easily remove solder from even the most difficult to remove components, such as the 10-pin Omron relays. I prefer the Soderpullt (tm) ESD safe model AS196 (about $25), since its chrome plated tube just works smoother than their other blue and yellow model which I also have. I have a Hakko 808 desoldering gun (about $180) for the really "challenging" work. :-) If you use Soder Wik (tm), be careful as it can lift pads easily if you apply heat for too long. Remember that the PCB is to be preserved at all costs, and a single component is a much preferred sacrifice if you put a part in wrong. Contact us for professional help and service if you are concerned about removing incorrectly installed connectors, R-packs, IC's, etc. We want to help you before you do something you'll regret later. Study the diagrams in the manual on how the PCB connectors are installed on the various PCBs, and you won't make a costly or serious mistake. So do not use drills, Dremel tools, hatchets, axes, chain saws, etc. on the PCBs...... You get the idea. Invest in the proper desoldering equipment or employ someone else who has the correct tools to do the work for you. We may return your kit unrepaired if PCB damage due to drilling is found. This falls into the same category as using acid core solder, soldering guns or propane powered soldering tools, etc. See our website for more precautions and tips on soldering. http://www.elecraft.com/Apps/construction_notes.htm Wayne will hopefully add a warning against this hazardous practice in subsequent manual revisions. We also have a new series coming soon on proper soldering techniques. Watch this reflector and the Elecraft website for information about this. Thanks. Gary Surrency AB7MY Elecraft Technical Support support at elecraft.com (use this email address for all support issues, not this juno account). +++++++++++++++++++++++++++++++++++++++++ Date: Wed, 09 May 2001 17:35:34 -0700 From: Eric Swartz WA6HHQ - Elecraft Subject: [Elecraft] New 'Tech Notes' Soldering Article by N0SS We have added a neat soldering article (pdf) to our 'Tech Notes' section at http://www.elecraft.com It is titled: 'What to do, and what NOT to do, to get excellent solder joints', By Tom Hammond, N0SS (Thanks Tom!) This is a great article and should go a long way to helping new builders (or those of us who need a refresher course) make perfect joints the first time. Tom includes color pictures of good, and BAD, solder joints and component mounting. Links to it are also on our Builder Resource Page. 73, Eric WA6HHQ ++++++++++++++++++++++++++++++++++++++++++++++++ Date: Fri, 11 May 2001 13:26:24 -0700 From: Eric Swartz WA6HHQ - Elecraft Subject: Re: [Elecraft] Solder Actually we now prefer regular old 60/40, 63/37 etc. solder like 'Kester 44'. We have found that the silver solder is harder to remove when sucking out solder to remove components. In addition to Kester 44, the Radio Shack solder works well. 73, Eric WA6HHQ Craig Nicholson wrote: > > Elecraft recommends Kesler 2% silver solder. Wonder what the basis for this > is? > > --Craig KW9R +++++++++++++++++++++++++++++++++++++++++++++++++ Date: Thu, 17 May 2001 18:18:34 -0600 From: "James E. Fuller" Subject: Re: [Elecraft] The Tools At 05:37 PM 5/17/01, Craig Nicholson wrote: >I'm expecting arrival of my K2 tomorrow and would like feedback concerning >the soldering tools I have. > >I plan to use a 25W Weller soldering iron with chisel tip. If you have a good touch with it, and if it has a small tip (~ 1/32 inch), then it should be OK. A temperature controlled "soldering station" is much better, in the sense that it is easier to make good solder joints without hurting anything. >Solder is 97/3 >(tin/copper) solder; .050 diameter. Not good. Bad. 63/37 (Sn/Pb) is best. Kester, Ersin, or Alpha Metals rosin core 63/37. .025, .020, or so. Some .050 or .062 is very handy for tinning the iron and for tinning leads, but it's awkward to use for the actual soldering because it's too big. - -- Jim Fuller +++++++++++++++++++++++++++++++++++++++ Date: Tue, 22 May 2001 02:44:15 -0700 From: "Ron D' Eau Claire" Subject: RE: [Elecraft] K2 Q7 & Q8 collector at 133 Ohms George, W6YR makes a great point: > I am sure that most of the old timers know this, but conventional > VOM types > of ohmeters usually are constructed to that the negative lead has a > positive voltage on it when in the resistance mode. Conversely, > most modern > DMM's have a positive voltage on the positive lead for resistance > measurements. I would add the if anyone has an old VOM, it's very smart to check the amount of voltage it is putting on the probes to measure resistance too BEFORE it's used on any modern gear. I used to have one that used 22 VDC for the resistance checks! That's no problem for old tube equipment but deadly in a rig like the K2. Also, even though some of them may use only 1.5 VDC for resistance measurements, they may not have adequate current limiting to avoid destroying a junction in a transistor or diode in the low-resistance ranges. Ron AC7AC K2 # 1289 +++++++++++++++++++++++++++++++++++++++ Date: Fri, 25 May 2001 12:33:37 -0400 From: Mark Dulcey Subject: Re: [Elecraft] Transistor collector question Gay Family wrote: > > The question (I'm a newbie at this) - how can I locate the collector on a > soldered in transistor? Can't find a clue in either the manual or the ARRL > Handbook. The answer depends on the type of transistor; different parts have the pins in different orders. The first page of Appendix B of the K2 manual has diagrams of the pin layouts of all the transistors used in the K2. For the final output transistors (the ones where you'll be doing resistance checks of the collector most often - you need to check every time you remove and reinstall the heat sink), it's even easier - the pin identities are silk-screened on the top side of the K2 circuit board. - -- Mark J. Dulcey mark at buttery.org Visit my house's home page: http://www.buttery.org/ Visit my home page: http://www.buttery.org/mark/ Big brother is listening... K2 #1984 +++++++++++++++++++++++++++++++++++++++++ Date: Fri, 25 May 2001 12:33:48 EDT From: N2EY at aol.com Subject: Re: [Elecraft] should I ...... To answer the question: Yes, you should. But be warned - building stuff is habit forming. In a message dated 5/25/01 1:15:42 AM Eastern Daylight Time, RES0AQDS at verizon.net writes: > You should get an anti-static mat, one of the controlled temp soldering > irons -- I use the Weller WCTPT with a 1/32" screwdriver shaped, 700 degree > tip, and Kester 245 solder (or the equivalent). Some folks use 2% Silver, > but this will make component removal much more difficult when you need to do > it. Also, get some soldering braid, and a good solder puller (I use the > ESD-safe SilverStat Soldapullt Model Number AS196). Good advice. I got the WCTPK version of the above. It's the military surplus kit that has the whole thing in an OD metal box, and the iron plugs in with a 4 pin Jones connector. It comes with a big set of tips, including a bunch of desolder tips and the special bulb-type sucker thingy. The gadgets alone are worth the price, and the case lets you put it all away neatly. But it doesn't include a sponge or the PTF-7 tip. I got two PTF-7s (digikey PTF7-ND) some 21 gauge 63/37 solder (KE1102-ND) and a wrist strap (SCP172-ND) to update the toolkit. The WCTPKs are available from several sources (www.tubesandmore.com has them for $99.95, plus shipping) but I got mine on eBay for less ($87 including shipping from AZ). You have to search eBay a bit to find them, because the sellers don't always know they are a WCTPK, or that they are made by Weller. The Xcelite cutter/pliers pair at Home Depot looked neat, but I've already got plenty of those. - -- K2 #2084 passed Phase 1 testing perfectly, powered by a couple of batteries salvaged from old Polaroid film packs. Those flatbatts must be 15 years old, but they still gave over 6 volts each open-circuit. Now to get it to play... 73 de Jim, N2EY ++++++++++++++++++++++++++++++ Date: Mon, 28 May 2001 19:29:29 -0700 From: "John Grebenkemper, KI6WX" Subject: [Elecraft] Setting Audio Levels in Spectrogram Recently a number of folks on the reflector have been using Spectrogram to make measurements of the K2's filter response. If the audio input level is set too high, clipping will occur in the sound card which will create intermodulation distortion and incorrect readings from Spectrogram. This problem is particularly apparent when measuring broadband noise which is done when making filter response measurements of the K2 filters. For making filter measurements, Spectrogram should be set to 11K Sampling Rate, 16 bit, Mono, and 512 FFT. You can set the other parameters where you want, but I would recommend using the 90 dB dynamic range since it will provide valid measurements as long as you don't overdrive the audio input. For some reason, v6.0.9 displays levels that are 10 dB less than v5.1.6 for the same audio input signal. All measurements given below are for v5; v6 users should set the following guidelines 10 dB lower. When making measurements with the SSB filter, intermodulation distortion will occur when the noise level exceeds -35 dB on the Spectrogram scale.. To leave some headroom, I would recommend taking these measurements with a maximum level of -40 dB. The narrower CW filters with a bandwidth <1kHz provide less noise power so one can measure to higher levels without clipping. These filters start to show intermodulation distortion when the Spectrogram level exceeds -30 dB. Again to provide some headroom, the audio level should be set so that the narrow CW filters do not exceed -35 dB in Spectrogram. A pure tone can be measured to somewhat higher levels in Spectrogram. One measurement I made showed that an over the air carrier received by the K2 started to show intermodulation distortion when the level approached -20 dB on the Spectrogram scale. Any sort of complex modulation would show intermodulation distortion at lower levels. To be absolutely safe, the Spectrogram levels for noise can be followed and you will be guaranteed not to have intermodulation distortion problems in the Spectrogram measurements. In summary, if you use Spectrogram to make K2 filter measurements, make sure that the displayed signal level in Spectrogram does not exceed -35 dB (-45 dB for version 6) for filter bandwidths less than 1 kHz and -40 dB (-50 dB for version 6) for bandwidths wider than 1 kHz. - -John KI6WX ++++++++++++++++++++++++++++++++++ Date: Wed, 30 May 2001 08:41:01 -0500 From: Tom Hammond =?iso-8859-1?Q?N=D8SS?= Subject: [Elecraft] "Soldering Tips"... Don, et al: W3FPR wrote: >I assume you already know how to read and follow the instructions, so I >submit that there are many other ways to hone your soldering technique - >such as getting a universal PC board from Radio shack and soldering in some >wires - when you can produce consistently good solder joints with that >combination, you are ready to solder the K2. I believe there is some >information on soldering either at the Elecraft website - if not there, >check out Tom Hammond's (N0SS) website. The subject article is available at: http://www.elecraft.com/TechNotes/N0SS_SolderNotes/N0SS_SolderNotesV6.pdf It is, however, NOT available on my web site: http://home.earthlink.net/~n0ss 73 - Tom N0SS +++++++++++++++++++++++++++++++++++++ Date: Thu, 31 May 2001 17:25:33 -0400 From: Subject: [Elecraft] Replacing standoffs for Q7 & Q2 of K2 A very minor suggestion, but I gather some folks have been frustrated trying to replace the washers and fiber standoff under the tab of the two power transistors, Q7 and Q8, after they have already been soldered in. The following method makes it easy. With the K2 on its side, slowly insert a long 4-40 screw the wrong way (from the bottom toward the top side of the PC board) with your left hand and, as you do, use tweezers to place the nylon shoulder washer, then the phenolic standoff, and finally the black fiber washer in its path, so that when it passes through the PC board hole the standoff components end up held in place by the screw. Then, with your left finger tip pressing gently on the screw head, turn the K2 over so that it lays in your left hand and the end of the screw is seen projecting up through the bottom of the PC board. Then take the proper screw in your right hand fingers and press it down against the original screw held in place by your light finger pressure. As the top screw pushes the bottom one out, the spacer assembly easily remains in place as the screw passes through the transistor's tab hole, and you are ready to proceed. The only "gotcha" here is that you need to be sure you are not inadvertantly pressing the screw against the tab instead of through its whole and bend its leads. - -- Haines Brown brownh at hartford-hwp.com www.hartford-hwp.com KB1GRM +++++++++++++++++++++++++++++++++++++++++++ Date: Wed, 06 Jun 2001 18:25:17 -0500 From: "George, W5YR" Subject: [Elecraft] WTCPT - One More Time Well, RadioShack.com finally came through and a brand new $89.99 Weller WTCPT soldering station is installed on the W5YR workbench with several kits piled up and waiting to "melt solder!' Thanks to all who recommended this piece of equipment and who advised on its availability, etc. One additional question: the iron comes equipped with the PTA7 tip. Is this the recommended tip to use for K2 assembly? I seem to recall reading on one of the Elecraft listings of a different tip. - -- 72/73, George W5YR - the Yellow Rose of Texas QRP-L 1373 NETXQRP 6 Fairview, TX 30 mi NE of Dallas in Collin county EM13qe Amateur Radio W5YR, in the 55th year and it just keeps getting better! Icom IC-756PRO #02121 Kachina #91900556 IC-765 #02437 +++++++++++++++++++++++++++++++++++ Date: Mon, 11 Jun 2001 13:56:47 -0500 From: "George, W5YR" Subject: Re: [Elecraft] K2 Front Panel Flathead Screw While flying bolts can be fun and exciting, there is a pretty easy way to ensure that (a) the bolt remains out of orbit and (b) it is cut where you want it to be and the threads are not hosed up. Simply run a nut down on the bolt leaving the amount to be removed exposed. Clamp the bolt in a vise with the exposed end accessible to the tool: file, Dremel, hacksaw, whatever. If the bolt tries to rotate, simply run another nut on as a lock-nut to secure the whole assembly. Remove the exposed material down to the nut surface. Run the nut back out over the cut-off portion to redress the threads. With a fine file or emery cloth, lightly chamfer the edges of the cut surface. That's it . . . 72/73, George W5YR - the Yellow Rose of Texas QRP-L 1373 NETXQRP 6 Fairview, TX 30 mi NE of Dallas in Collin county EM13qe Amateur Radio W5YR, in the 55th year and it just keeps getting better! Icom IC-756PRO #02121 Kachina #91900556 IC-765 #02437 Louis Hlousek wrote: > > < and > proceeded to a low geostationary orbit. >> > > I always find using my dremmel tool to cut down screws to be fun and > exciting. However, for the sake of accuracy I would like to point out > that there is only one altitude for which screws (or other satellites) > can be in a geostationary orbit. That is ~ 22,500 miles. Lower than > that and the orbit is faster than the rotation of the earth and higher > than that it is slower. > > Lou W7DZN ++++++++++++++++++++++++++++++++++++++++++++++++++ Date: Fri, 15 Jun 2001 07:37:40 -0500 From: Tom Hammond =?iso-8859-1?Q?N=D8SS?= Subject: Re: [Elecraft] K2 s/s 2066 Cap marking question Ed: >The C122, C24, and C20 are NPO 56pf units. I got two that are marked 560j >and one marked 56j. These markings are a both 56pf. Right? Correct... different manufacturers... some persist in using the 'older' numbering nomenclature... probably just to screw us up. >The C22 and C23 are NPO 3.3 or 2.7pf units. I got two capacitors marked >2R7. I >think that the R that I see is really a II for a 2II7. The manual says the >3.3pf could be marked as 3II3. Just wondering if anybody else saw 2R7 or >is it >just my eyes playing tricks on me. Actually, the 'R' is not an uncommon substitute for a decimal point. In fact, when operating CW, the letter "R" is very often substituted for a decimal... esp. in commercial CW settings. Much quicker than sending a 'period' (.-.-.-). The other decimal divider was more like a double split bar "||" instead of a double "I", but, again, was intended to replace the decimal point... 3||3 = 3.3 pF. I believe I've seen other characters used to replace decimal points, esp. in European numerical representations... unfortunately, I cannot for the life of me recall exactly WHICH characters (letters) were used.... Oh... I believe 3K3 is sometimes used to indicate 3.3k... and probably other similar formats as well. Tom Hammond N0SS ++++++++++++++++++++++++++++++++++++++++++++ Date: Sun, 17 Jun 2001 08:39:25 -0500 From: Tom Hammond =?iso-8859-1?Q?N=D8SS?= Subject: Re: [Elecraft] Flux cleaners? WARNING!!!!! Both Toluene AND Xylene (and others) will MELT plastics!!!!! NEVER use these strong solvents in the presence of ANY PLASTIC devices (knobs, shafts, relyy covers, painted surfaces). Use nothing stronger than alcohol (medical grade 99%-100%, or denatured, NOT rubbing alcohol). Tom Hammond N0SS Frank Kamp wrote: >Yes, remove the flux. It makes for a cleaner looking board but it is >only really necessary for high impedance circuits that could be degraded >by high resistance leakage to ground or to other circuits. > >I used to use Toluene, Xylene works just about as well, as does rubbing >alchohol. Dont forget to clean the board with something similar to 409 >after using the flux solvent. Then wash with plenty of warm water as >long as there are no coils or transformers involved. Need to use some >common sense here. If the components are potted or otherwise >encapsulated a hot water rinse will not hurt anything, but wait until >the board is dry before powering up. > >There are such products as solder containing water soluble flux. The >water soluble flux is conductive. It takes a LOT of water to rinse off >the conductive residue. +++++++++++++++++++++++++++++++++++++++++++++ Date: Sun, 17 Jun 2001 09:01:18 -0500 From: Tom Hammond =?iso-8859-1?Q?N=D8SS?= Subject: [Elecraft] Flux cleaners / water? Jerry: >Ok folks: I gotten serveral yes and a couple no. >Within it all the thing that really caught my attention was >washing the boards with water. >Help me out here!! >What about the latching relays, I. C.'s, etc. >Are you telling me that I can wash these parts with water and it won't >hurt them? >Obviously if I were to do this, I would allow ample time >for things to dry but this is not something that I would have >considered an appropriate act. While MOST(!) current-manufacture devices (incl. relays and ICs) are designed to be tolerant of water washing, I DO NOT recommend it for non-commercial construction. Water washing works well for commercial manufacturers, where they KNOW the exact limits of their designs and they have the equipment specifically designed to perform the process. We do not, and should not risk possible (INADVERTENT) damage to our kits caused by our ignorance of precisely HOW to wash the PC boards. Furthermore, in 90% of the instances, a water wash is not required. >The KNB-1 is complete for my K-1. I have cleaned the flux from it. >Made it look much better and true to some of the response's I got, you can >really see your solder work clearly. Agreed... if you feel it necessary to remove flux, find and use a flux remover which is RESIDUE-FREE. Generally, this can be tested by spraying a small amount onto a piece of white typing paper. If, when the flux remover dries, it leaves no translucent spot (indicative of a possible oily additive), then you can probably use it. Note that, unless you flush the PC board REALLY WELL with additional flux remover, there's always a chance that a thin layer of dissolved flux may remain once the flux remover has evaporated. This layer may dull in time, and may actually turn out to be a dust attractant. Certainly not what you intended either. Finally, note that gratuitous (overzealous) use of flux removers can also contribute to potential problems if not used properly... dissolved flux, running everywhere on the PC board can seep into friction-type joints, such as those on minature variable ceramic capacitors, where, when the flux remover evaporates, you wind up with a nice thin layer of insulative rosin between the rotating contacts of the cap. I've seen only a very few comments pass through the reflector wherein a problem was actually traced to a high impedance connection which may have been compromised by the presence of flux on the PC board. My personal recommendation is to 1) use a low-residue solder, 2) use a .020" to .025" diameter solder (so you can better control the amount used), and 3) be judicious with your use of solder on each joint. These three suggestions alone will contribute to better joints and less residual rosin when you're finished. >Now, do I wash this thing with water to remove any residue? >In disbelief but very curious: I'd not attempt to tell you what to do, but allow me to say that I'd certainly not wash my PC boards unless I had already managed to screw them up so badly that washing them could only make things better... and they'd have to be SOooo bad at that point that it'd not make any difference. As always, dissenting opinions are most welcome... as long as they're kept to a friendly note. 73 - Tom Hammond ++++++++++++++++++++++++ Date: Sun, 17 Jun 2001 09:11:53 -0500 From: Tom Hammond =?iso-8859-1?Q?N=D8SS?= Subject: [Elecraft] More on Flux Removing Although I forgot to mention it in either of my previous postings, the WARNINGS from Both Tim Raymer (KA0OUV), and Larry East (W1HUE/7), regarding the SPARING use of flux removers AND the use of tightly-wound cotton swabs for its application, are very WISE and SAGE COMMENTS! Take these gentlemen's words to heart... they know from where they speak. Tom N0SS +++++++++++++++++++++++++++++++++++++ Date: Sun, 24 Jun 2001 16:44:44 +0200 From: "Ingo DK3RED" Subject: [Elecraft] Re: C73 ? Hello Alan, > ... Does the "0" on the > 470 indicate a multiplier of some sort, or do I have the wrong caps? 470 is OK. The 47 is a capacity older production. The 470 means 47 with 0 extra zeros. 471 -> 47 with 1 zero -> 470 pF 472 -> 47 with 2 zeros -> 4700 pF = 4.7 nF etc. 72 de Ingo, DK3RED E-Mail: dk3red at qsl.net - Homepage: www.qsl.net/dk3red +++++++++++++++++++++++++++++++++++ Date: Sun, 01 Jul 2001 13:40:11 -0600 From: Larry East Subject: Re: [Elecraft] K1 rookie-builder needs help! At 11:34 AM 7/1/01 -0600, Rod Cerkoney, N0RC wrote: ...snip... > The only >thing I would add, get a "REALLY GOOD" slug tuning tool. The tool >supplied by Elecraft is OKAY, but it has a little flex. A good stiff >tool will help eek out that last little bit of performance. Some time ago someone ... perhaps it was you, Rod ... asked about ceramic tuning tools. There was some discussion, and the general consensus seemed to be that they were too expensive. Well, they are indeed a bit pricey. However, I decided to "spring" for the "four in one" tool sold by DigiKey (part # 243-1014-ND) for $28.97 (it has two Phillips and two flat blades). This turned out to be one of the best tool investments that I have ever made! (See note below for other good tool investments). I was a bit concerned about the ceramic blades being fragile, but they seem pretty sturdy. However, I wouldn't advise using one to "unstick" a "frozen" coil slug -- that is best done with a jeweler's screwdriver (carefully so as not to break the slug!). No more futzing with crummy plastic tools that bend and deform. No more playing "touch and try" with metal tipped tools on ungrounded trimmer caps! WHOOPEEEE!!! These will NOT work on coil slugs that require an Allen-type tool -- but I've had good luck with plastic tools on those. Metal tipped tools usually work OK on "notched" slugs -- but sometimes not (it's also easy to break a small slug by applying too much pressure with a metal tipped tool). Other good tool investments that I have made over the years (in no particular order): 1) Bench top drill press. 2) Two "step bits" (also called "unibits") -- boy, do they make clean holes in metal panels! 3) A good florescent bench lamp with magnifier. (Now I can see where those parts go!) 4) A Dremel tool. 5) A nibbling tool. 6) A good soldering station (Weller WCTP series). 7) Some assorted dentist's picks. 8) A good pair of tweezers. And of course, the usual assortment of screw drivers, Allen wrenches, cutters, etc. 72/73, Larry W1HUE/7 ++++++++++++++++++++++++++++ Date: Tue, 10 Jul 2001 17:35:28 -0700 From: Gary L Surrency Subject: Re: [Elecraft] K1 on order! Hi Brad, Other than the excellent points you made, the most important thing IMHO, is to solder as well as possible and tin those toroid leads! Try to make your PCBs look like commercially wave-soldered boards. To many people do not put the effort into soldering the kits they should. This is a very important process, so don't rush through building the kit. I see more kit failures due to poor soldering and PTTL than any other reason. It accounts for probably 90-95% of all problems with the kits. Tom Hammond N0SS has written an excellent soldering tutorial that everyone should read: http://www.elecraft.com/TechNotes/tech_notes.htm It seems from the kits I work on here, that many people use way too much solder and do not heat the connections long enough to flow the solder and remove the flux. This results in cold solder joints, and excessive flux on the PCBs. Use as little solder as required to just fill the connection flush or form a small fillet of solder around the lead. See N0SS's photos. Don't build for too long at one time, or stay up until the wee hours of the morning! :-) Good luck with your kit(s)!! Here's hoping you have zero problems!! 73, Gary Surrency AB7MY support at elecraft.com (Use this address for all official tech support questions, please). On Tue, 10 Jul 2001 15:09:11 -0500 "Brad Johnson" writes: > I just placed an order for a K1, KNB1, and KAT1. I have not assembled > a kit > since I was a kid in 1974...Heathkit DX60B (which fried the wire > harness on > first power up!) I want to assemble a K2, but am a little > intimidated by it > right now. Watching something I spent hours on go up in smoke was a > traumatic experience from which I still haven't completely > recovered. What > can I say...I have a long memory...still can't look at a bottle of > cherry > vodka without getting queasy (1977) . > > Be it resolved: > > I WILL carefully inventory the components > > I WILL read the instructions carefully before beginning > > I WILL NOT attempt to assemble the K1 in one sitting > > I WILL NOT consider toroids to be the devil's most heinous creation > > I WILL ask for help if I get confused > > I WILL NOT eat cheese dip over the work in progress > > Okay...I can do this....definitely maybe! > > 73, > > Brad > AA5CH ++++++++++++++++++++++++++++ Date: Wed, 25 Jul 2001 08:28:01 -0500 From: Tom Hammond =?iso-8859-1?Q?N=D8SS?= Subject: Re: [Elecraft] K2 # 1926 passes test part 2 but query re bfo settings Hi Vic: >I set mine up per the table in the manual (page 86), but these don't seem to >be anywhere near right for my radio. As set , all cw signals seem to be very >low pitched (and not very loud) but then disappear as I tune across the >signal. This suggests to me that the bfo settings are too high or too low >and that I am losing the signals out of the passband at the wrong point. Yeah... the table of settings is really only to enable you to get a 'ballpark' setting... more than anything, to ensure that you get the BFO set to the correct SIDE of the filter for the sideband being received. Actually, they're intended to be a bit closer than that, but in real life, they do leave a bit to be desired. >I was a bit short of time so I tried moving the bfo for FL1 . This improved >matters a lot and received signals are much better now. > >I am inclined to try this method again to get signals sounding right and not >worry about the bfo frequency. > >Any thoughts? > >Also I couldn't get ssb signals resolved at all despite some twiddling of >the bfo freq. > >Can I expect to resolve ssb with FL1 in its widest setting? YES! Absolutely! >I imagine that I should be able to although they might be rather tight on >audio response. > >Any thoughts appreciated. Yeah... download a copy of Spectrogram: http://www.monumental.com/rshorne/gramdl.html to run on our PC, with your sound card. Make up a patch cord to go between the SPKR/PHONES output of the K2 and the MIC INPUT of your sound card. Then download the Spectrogram alignment instructions from the Elecraft web site: CW Alignment http://www.elecraft.com/Apps/new_fil_docs/k2_cw_gram.pdf SSB Alignment http://www.elecraft.com/Apps/new_fil_docs/k2_ssb_gram.pdf If you find (as many have) that you can't obtain enough 'band noise' to adequately align your K2, consider building a broadband noise source (probably about 6 pounds your cost) from the schematic that is available at: http://www.elecraft.com/Apps/new_fil_docs/noise_source.zip PC boards are available, but there is no reason at all that you could not build the device using just about any assembly technique (point-to-point, dead bug, Manhattan, etc.). The components are NOT terribly critical in value AND should all be available in the UK. >PS "Lo Batt" message is appearing even though my psu is delivering 11.6v. Is >this normal - manual suggests the message kicks in at a lower voltage (11 v >I think) You will have something on the order of 0.6VDC voltage drop THRU the K2, by the time the voltage gets thru the reverse polarity diode and the solid state fuse. So you're seeing exactly what you should see. 73 - Tom Hammond N0SS +++++++++++++++++