Re: [Elecraft] Cleaning solder flux
In all of the places I worked beginning with the Air Force we used isopropyl alcohol to remove flux from repairs on boards with the exception of one. At I believe General Radio(GenRad) in Rockville, Md we used banana oil for flux removal. Has anyone else used something other than alcohol?? Jim/W3FA On Sun, Jan 2, 2022, 10:13 Dr. William J. Schmidt wrote: > During my under-graduate and graduate school careers, I worked at > Honeywell's circuit board fabrication shop for about a year and a half. We > had two machines in the shop that dealt with flux: a reflow machine and a > parts set machine. The reflow machine was used to reflow the solder after > plating so that it looked shiny. The board was emersed in a 601-type flux, > heated to about 425F, cooled down, and then scrubbed (brushed) with > Isopropanol alcohol three times (stages) with a water rinse and force-air > dried (all automagically). The solder was beautiful and shiny at the end > of > this process. The parts-setting machine was similar... the whole > (pre-reflowed) board was fluxed, the parts set, heated, and then cleaned. > All fluxes come off with Isopropanol alcohol (remember IPA is polar like > water and works that way). > > > > Fluxes come in various forms... some are more corrosive and some not... so > you should follow the directions (right off the website). Rosin can remain > on a board, but also can be problematic because it can collect debris (dust > and other unwanted materials) because its plastic (flows at room > temperature) sticky. Many of the water-soluble fluxes are more acidic, and > will tarnish the solder joints if not removed. > > > > On the subject of using water on electrical components... most components > (particularly if they might be mil spec) are made for water emersion (NOT > ALL!). In my office lab we routinely clean circuit boards by scrubbing > them > with just water and force-drying them. Works fine. About a decade ago, I > used to buy up surplus AM/ broadcast band transmitters for repurposing to > other countries (mainly south America) for the Christian broadcasting > markets. Once back at my shop, the first stop was a good through power > washing in the driveway (paper and other water damaged goods removed of > course) followed by a good drying (leaf blower). Works fine! > > > > > > Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ > VP2EHZ > > > > > > -- > This email has been checked for viruses by AVG. > https://www.avg.com > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to jimw...@gmail.com > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
[Elecraft] Rx QTC issue
I am able to send QTC fine. Both times receiving QTCs in WAE I can click on the header and it populates but no QTCs populate the individual QTC blocks. When clicking on a QTC it tells mwe format is incorrect. I have the original QSOs for each QTC block so I can find where to add them for the appropriate calls. I did a screen copy of the info so I have the QTC info. Can this info be entered manually into the QTC window and have it enter the log, which doesn't seem to work unless it's me. Any ideas to get these Rcv QTCs into the log? Thanks, Jim/W3FA __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Inverted L for 160 meters
For mine I have 1/4 wave wire for 160, goes up 35-40 ft and over to pole in corner of the yard with the remainder of the wire. I use mostly random length ground radials on top of the ground, some 1/4 wave, some sorter, some longer, mostly shorter,(someway shorter thanks to the lawn mower height), 12 so far and I add more when I get extra wire. 100 watts I work from here in Maryland to US west coast, Caribbean and into Europe and north Africa. I am happy for now but want to get more vertical height some day. Radials are sections of free 2 each 1000 foot rolls of 4 pair cat 5 cable. Jim/W3FA On 8/25/2020 19:23, kevinr wrote: From what I can find, and what I can calculate, five wires, each ~130 feet long, could make a nice inverted L for 160 meters. One leg for the vertical and horizontal portion of the antenna. Four legs for the counterpoise (ground plane). There are many broken wire antennas stored in my shed which are fodder for the radials. Do all of the legs for the counterpoise need to be 1/4 wavelength or can I substitute some shorter lengths? The feedpoint should somewhere above 50 ohms impedance. As I add more radials that number will reach 50 ohms asymptotically. I can get the vertical part up to 70 or 80 feet above ground with the rest of it horizontal. Most of the radiation should take place from the vertical part since it is closer to the feed point. But there should be some effect from the direction of the horizontal portion. How strongly does the direction of the horizontal portion effect the radiation pattern of the antenna system? My property allows me to point it from 300 degrees around to 200 degrees so I have plenty of options. Between 200 and 300 degrees there is a road used by loggers, and the folks maintaining the towers at the top of this mountain. They can break any antenna lower than 80 feet above ground. Spar poles and cranes clear out any dead limbs across the road. Inquiring minds... Kevin. KD5ONS __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to jimw...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Earpads Shedding
I went online and got packs of the cloth headphone earmuff covers for mine. Work good, washable, stretchable, several in a pack, inexpensive. I got a small pack and large pack. large covers the yamaha 500 headphones well. Smaller ones cover the cheaper music headphones. Jim/W3FA On 5/6/2020 13:58, Tommy Judson via Elecraft wrote: ...earpads are flaking pretty badly, leaving little back bits around the home office/shack… Took me a while to realize it was my earpads shedding, glad to read this isn’t an isolated occurrence. Now how to remedy that problem? __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to jimw...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
