In my years in the radio and electronics hobby I have learnt that the magic smoke wants out as well
Fred VE3FAL Sent from my iPhone Fred VE3FAL/CIW649 > On Nov 20, 2018, at 19:40, John Simmons <[email protected]> wrote: > > Ha! I would venture to say that anyone that says they haven't done this kind > of thing would be fibbing. I've blown up lots of stuff: > > * When I was in high school electronics class, I wired an AC power > switch in some long-forgotten transmitter in PARALLEL with the power > line instead of SERIES. Fuse? Nah. > * I built a Heathkit SW receiver. I swapped the germanium diodes for > the RF detector with the silicon diodes for the power supply > rectifier. This time there was a fuse. > * I've put many transistors in backwards. The transistors protect the > fuse. > * Many times I've tried to work the local repeater without remembering > to connect the antenna to the radio. I've done this both in mobile > and home stations. I've never blown a final, though. > * Another Heathkit was a vacuum tube voltmeter. I wired all of the > resistors on the 10 position range switch EXACTLY one switch > position off. > * I blew up a $200 LDMOS transistor for an HF amp. I recorded the > whole thing on video and posted it to YouTube. I STILL don't know > how or why the transistor blew. RF Parts was happy to sell me > another one though. > * I had an old pickup truck that I used only for snow plowing. Both > battery cables were black (don't ask why). Every fall I would put > the battery in to prepare for the season. EVERY fall I would hook > the battery cables up backwards. BZZZT! > * I built my own house while working 60 hour weeks at a two-way radio > shop. I did all the electric wiring in the house. The first circuit > I hooked up was for basement outlets. By mistake I used the cable > for the water heater for the outlet string. BANG! GFI outlets don't > like 240V. > > That's just the electronic stuff I can remember right now. We had the kitchen > floor replaced THREE TIMES because the pipe for the self-installed > dishwasher leaked. > > Don't feel bad. > > -John NI0K > > P.S. Many, many years ago there was an article in 73 Magazine written by a > ham claiming that being a klutz was his specialty. He gave lots of examples, > but the crowning one described how he put out a fire in his car (which was in > the driveway) with the liquid from his septic tank that he happened to be > pumping at the same time. I saved the article. Every time I read it I get the > giggles. > > [email protected] wrote: >> Thanks Michael, Andy, and all for the original thread. It made me focus on >> proper use of my KPA500 which has really done a great job for me since I >> acquired it and a KAT500 over the summer. >> >> Retitled this message because I do not want to hijack/derail the original >> conversation. >> >> What I want to know... is there no repair for absent minded button pushing >> and thoughtless antenna positioning? >> >> So that I don't forget again... A hopefully instructional "mea culpa" >> follows: >> >> I have been using the IC-7000 for 2M APRS ops with a Diamond VX2000 >> vertical. Also have been experimenting with HF simplex D-Star and Free DV >> digital voice recently. The KPA500 has been instrumental for DV ops because >> of recent squirrely propagation... >> >> Mistake 1: Over the summer, I forgot to shut down the packet ops and ground >> 6/2/440 tri-band antenna while using a "nearby" halo with 350 watts 6M DV. >> That blew the 2M front end of the IC-7000. Matt at SARTS/ICOM in Michigan >> repaired it and I put together a protection relay circuit to ground the >> vertical if I forgot again. That should have solved the issue... >> >> Mistake 2: A relay contact was faulty (and I did not test it properly) and >> a month later, an adventure on 6M DV mode took the 7000 front end again! >> Matt was kind about fixing it ...again... >> >> Here I claim total stupidity along with absent mindedness - I rebuilt the >> protection circuit, tested it, it "seemed" to work fine... but it failed >> again a month later! >> >> Mistake 3: Failed, because I had removed the dummy load and *forgotten* to >> replace it along with a key ground strap, which again left the receiver 2M >> front end exposed. Kindly, Matt agreed to fix the 7000 a 3rd time... >> >> The 7000 will not go back into service until I have completely re-arranged >> the station set up because, to top off this comedy of errors... I totally >> ignored one basic issue: >> >> Original Mistake: the vertical and halo antennas were mounted on the same >> mast because "I never planned" to use them at the same time. This is where >> stupidity/laziness compounded with my absent minded operating practices to >> create the "perfect storm". Until I started using the KPA500, the halo >> antenna field strength was not such that the 7000's 2M receiver section was >> stressed by the signal strength from vertical, so I got complacent. Add in >> the KPA500 and smoke is let out of Q551 in the IC-7000. >> >> I am *sure* that no one on this group does this sort of sloppy engineering, >> but let it serve as a not-so-subtle reminder that a station layout should >> not be organically grown, but should be planned carefully with this sort of >> damaging interaction in mind. Enjoy the laugh at my expense. >> >> KD4IZ >> Jack Spitznagel >> FM19oo >> >> >> >> -----Original Message----- >> From: Michael Walker<[email protected]> >> Sent: Monday, November 19, 2018 19:52 >> To: ANDY DURBIN<[email protected]> >> Cc: [email protected] >> Subject: Re: [Elecraft] Killed the KPA500 :) >> >> Knowing what I did while transmitting at 100 watts of msk144, I’m surprised >> the damage isn’t worse. >> >> The protection circuits did the best they could of. >> >> If you own any amp, you always need to be aware of the risk. I would never >> rely on the automation to 100% protected any amp. >> >> If you are worried about your amplifier and anyway I highly recommend you >> have checklist handy every time you turn it on and change Bands. Never >> depend on the protection circuits. >> >> I know I’m preaching to the choir too many people, however it is imperative >> you understand exactly how your amp works, how it’s wired, and how it >> interfaces with any HF radio. >> >> Mike va3mw >> >> >> >> Sent from my iPad >> >>> On Nov 19, 2018, at 6:45 PM, ANDY DURBIN<[email protected]> wrote: >>> >>> "The support team at Elecraft got back to me and the required parts to >>> repair the board are on the way. Nice job guys." >>> >>> >>> But the question remains - Why didn't the designed-in protections work? >>> This new KPA500 owner would appreciate an answer from Elecraft. >>> >>> >>> Andy, k3wyc >>> >>> >>> ______________________________________________________________ >>> Elecraft mailing list >>> Home: http://mailman.qth.net/mailman/listinfo/elecraft >>> Help: http://mailman.qth.net/mmfaq.htm >>> Post: mailto:[email protected] >>> >>> This list hosted by: http://www.qsl.net Please help support this email >>> list: http://www.qsl.net/donate.html Message delivered to >>> [email protected] >> >> >> ______________________________________________________________ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:[email protected] >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html >> Message delivered to [email protected] > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:[email protected] > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to [email protected] > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
