[Elecraft] K2 filter alignment problem
I have aligned my K2 crystal filters with Spectogram many times, but this time I've run into a problem that I can't figure out. Using Don's [and the manual's] instructions, I can align F1,F2,F3 in decreasing bandwidths. All works as per expectations. On F4, the alignment goes "ok," [as per Spectogram] but when I use it with on-the-air signals, the signal "disappears" and shows up about 900 cps lower and in "reverse" orientation [BFO on opposite side]. When the signal disappears, I can change filters [F1/F2/F3] and it's right there where it should be with the bandwidth getting narrower as expected. But, switching to F4, it's gone. I have tried changing the BFO frequency throughout its whole range when in F4, thinking that I've aligned it on the "wrong" side. No luck. I'm stumped. Any and all suggestions welcomed. ...robert -- Robert G Strickland, PhD ABPH - KE2WY rc...@verizon.net.usa Syracuse, New York, USA __ 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
Re: [Elecraft] Measuring SWR (Long)
It was a feeble attempt at humor, given the nearly countable infinity of posts here on baluns over the last few years including but not limited to what they are, what they aren't, how they work, do they even work?, and do they even exist at all. Perhaps my attempt was more feeble than I thought. [:-) And, yes I know that "near infinity" is meaningless. 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County On 4/10/2019 11:13 AM, Bob McGraw K4TAX wrote: Hu...see: http://www.dj0ip.de/balun-stuff/ I seem to think this fellow has a good grasp about the "alien origin" of baluns. 73 Bob, K4TAX On 4/10/2019 12:23 PM, Fred Jensen wrote: It also spawned the "balun," a mysterious device that may be of alien origin since no one seems to know exactly what it does or how it does it. __ 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
Re: [Elecraft] Measuring SWR (Long)
What? You mean the guvmint has classified Carlsbad Caverns now? 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County On 4/10/2019 11:36 AM, K8TE wrote: We have one in NM, however I am not allowed to talk/write about it. No, it has nothing to do with Roswell. 73, Bill, K8TE __ 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
Re: [Elecraft] SWR - does it matter?
At a given operating point, there is always some load Z that will minimize amplifier dissipation (and probably another that minimizes IMD). The problem is, we don't normally know what it is, so guessing about it is pointless. Hence specs like X watts into Y SWR (nominal). Andy provided three data points. Changing the sign of the reactance will leave the same SWR, but more than likely different amplifier response. In fact, 50 +j0 might not be optimum. Who knows, maybe some point on the 1.5:1 circle on the Smith chart is better :-) Adding to this uncertainty is the fact that with the typical measurement circuitry in our PAs and tuners, we don't know the real SWR either. I, and others, discussed this in an earlier thread :http://elecraft.365791.n2.nabble.com/K3-SWR-Numerical-Indication-td7643839.html Wes N7WS On 4/10/2019 6:59 AM, Andy Durbin wrote: As a counter to those who are asserting that SWR 1.5:1 is a good enough match for an antenna system I offer measured data for the KPA500. At 14.005 MHz my KPA500, when connected to a 1.44:1 SWR load (R37, X9), had a PA dissipation of over 500 watts when producing 400 watts RF output. When the load was changed to 1.30:1 (R39, X3) the PA dissipation was about 410 watts. When the load was changed to SWR 1.07:1 (R49, X3) the PA dissipation was reduced to under 400 watts. (The plots are far more informative than a text description but I can't post them here). If you don't mind your KPA500 running hot, and are prepared to accept it shutting down with PA DISS fault, then 1.5:1 SWR may be good enough for you. I'd rather know the complex impedance of the antenna system load and avoid loads that result in high PA dissipation. 73, Andy, k3wyc __ 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
Re: [Elecraft] SWR and Power Output
I think that this was covered. You don’t run a solid state unit into a mismatch. The antenna tuner in effect takes the place of the output network that existed with tube rigs. Sent from my iPhone > On Apr 10, 2019, at 11:39, Eugene wrote: > > The reason SWR should be of concern is the effect it has on what is presented > to the solid state output device(s) in your radio. > The output power and final stage current is determined by the load presented > by the antenna/tuner and the output matching network. > The output power is, P= supply voltage squared divided by 2xR(load). A 2:1 > SWR could present a load either half or twice the design load for the 1:1 (50 > ohm) SWR match or some where in between those two points with a complex > impedance being presented to the output device(s). > Thus, the output power delivered by your radio and the final output device > current and efficiency is directly related to the "match" presented to your > radio by your antenna and/or tuner. > > Gene, N5LDX > > Sent from my iPad > __ > 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 > __ 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
Re: [Elecraft] Measuring SWR (Long)
I believe I run the highest SWR of anyone here. It is close to 100:1 in normal operation according to EZNEC (I have never tried to measure it). The line is open-wire line made with no. 12 (2mm) wire, only about 10m long. The highest SWR is on 40 meters, and I calculate the loss as around 1 dB. I calculated the peak voltage at around 7 kV. You know how the specs on vacuum relays have to be derated for RF? Believe them. After using various more or less complicated matching arrangements, I settled on an old Johnson KW Matchbox. It does the job on all bands from 40 through 10m, with just a little external help on 30m. The antenna is a simple rotary dipole whose total length is 10m. 73, Victor, 4X6GP Rehovot, Israel Formerly K2VCO CWops no. 5 http://www.qsl.net/k2vco/ On 10/04/2019 20:23, Fred Jensen wrote: Or 10:1 or even 20:1. However ... there's always a "however" or a "but" ... it doesn't matter. The dielectric constant of air [the insulator between open wire conductors] is very close to 1 whereas it is much larger for various forms of coax. Very high SWR creates very high voltages along the line. The energy storage with high dielectric constants is much higher than with air, and dielectric losses go up dramatically. In prehistoric times when we used vacuum tubes and resonant tank circuits, we coupled power to the line with a 2-3 turn link coil adjacent or in the middle of the resonant tank. If the line exhibited reactance, it detuned the tank which we just retuned to resonance ["Dip the plate, increase the coupling, repeat"]. The PA tank circuit became a thoroughly mis-named "antenna tuner." It didn't matter what the SWR was on the open wire transmission line, and in fact no one paid any attention to it. Then flexible coaxial cable was invented. It was much more convenient than open wire line, however in reasonable physical sizes, it had very low characteristic [surge] impedances ... 50 and 75 ohm impedances were the result and now, SWR mattered. The dielectric constant inside the cable was very much higher, and the higher voltages from high SWR resulted in much higher dielectric losses. Then, someone invented the Pi-network [for all of you with fingers poised over the keyboard to pounce on my description of history, relax and breath deeply. I'm making some of the non-technical stuff up to help hold your attention]. The Pi-network would transform the 50 or 75 ohm impedance at the end of the coax to the several thousand ohm plate circuit impedance of the PA stage and power would flow to the antenna unimpeded. It was at this point that sales of SWR indicators soared, SWR became a household abbreviation in the ham community, and an SWR of 1.000:1 became the Nirvana of ham radio. It has been thus ever since. As electronics progressed [?] from the vacuous to the solid state, SWR took on an enhanced importance since the solid state was far less tolerant of overvoltage and energy dissipation than the 807's, 813's, and 250TH's of the previous era. The resonant tank circuit faded, amplifiers now feed non-resonant filter networks and expect to see a 50+j0 ohm load ... or else! This made open wire transmission lines much more difficult to use, requiring some way to adapt a PL259 to connect them to the radio which is both mechanically and electrically hard, and sparked the incorporation of "SWR Alarms" into our radios. It also spawned the "balun," a mysterious device that may be of alien origin since no one seems to know exactly what it does or how it does it. I hope this helps. [:-) 73, Fred ["Skip"] K6DGW ex KN6DGW 1953 Sparks NV DM09dn Washoe County On 4/9/2019 7:21 PM, W2xj wrote: I agree except that even at 500KW a 2:1 or greater is the norm with open wire line. Sent from my iPhone On Apr 9, 2019, at 19:10, Fred Jensen wrote: Well, the reflected power is created by a "virtual transmitter" at the feedpoint of the antenna and heads down the coax which has a surge impedance of Z0 ohms. It meets the SO-239 at the TX and sees an impedance of Z1, the impedance presented by the PA and output filters. If Z1=Z0, the power is dissipated as heat in the PA and associated RF circuitry. If Z1<>Z0, some is dissipated and some is reflected, where some is radiated, and some is reflected [virtual transmitter again]. Ad infinitum, and when forever is over, it is all gone and everyone lives happily ever after. SWR and all the associated measuring equipment and concern with it only became an issue when: 1) Coax replaced parallel lines and; 2) Resonant output circuits were replaced by solid state amplifiers with non-resonant filters. When I sat for the Extra in early 1956, the only question that involved standing waves was one about how Lecher Lines could be used to measure transmitter frequency. It's important today but calculating it hasn't changed. At 10 W, a 2:1 SWR will probably work ok. At 1500 W, a solid state amplifier
[Elecraft] SWR and Power Output
The reason SWR should be of concern is the effect it has on what is presented to the solid state output device(s) in your radio. The output power and final stage current is determined by the load presented by the antenna/tuner and the output matching network. The output power is, P= supply voltage squared divided by 2xR(load). A 2:1 SWR could present a load either half or twice the design load for the 1:1 (50 ohm) SWR match or some where in between those two points with a complex impedance being presented to the output device(s). Thus, the output power delivered by your radio and the final output device current and efficiency is directly related to the "match" presented to your radio by your antenna and/or tuner. Gene, N5LDX Sent from my iPad __ 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
Re: [Elecraft] Measuring SWR (Long)
And for that reason as Roy stated, those components that are rated "legal limit" are done so under MATCHED conditions. Use a legal limit component in a condition where SWR is 2:1 or 3:1 or higher and one is likely to find it becoming a smoke generator at legal limit or even less. Case and point, the KAT500 ATU is rated at 600 watts, 3 - 30 MHz, 5 oh On 4/9/2019 7:56 PM, Don Sanders wrote: From memory now, at 2 to 1...feedline voltage nodes and current nodes can double -- no small thing when power is 1500 watts; can stress antenna system components. 73, RoyK6XK __ 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
Re: [Elecraft] Measuring SWR (Long)
Hu...see: http://www.dj0ip.de/balun-stuff/ I seem to think this fellow has a good grasp about the "alien origin" of baluns. 73 Bob, K4TAX On 4/10/2019 12:23 PM, Fred Jensen wrote: It also spawned the "balun," a mysterious device that may be of alien origin since no one seems to know exactly what it does or how it does it. __ 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
Re: [Elecraft] Measuring SWR (Long)
We have one in NM, however I am not allowed to talk/write about it. No, it has nothing to do with Roswell. 73, Bill, K8TE -- Sent from: http://elecraft.365791.n2.nabble.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
Re: [Elecraft] My "MFJ Posting"
Folks - We commented strongly on the post in question and closed this topic several days ago. Thread is CLOSED. I also posted that discussions criticizing others about race./culture etc. along with posts or direct emails criticizing those who made inappropriate posts are outside of list guidelines. See my earlier post, or email me for a copy if you did not see my earlier posting on our position on the original offensive post and these topics. Also if you you have complaints about any posting please email me as the moderator and I'll address it. Since I do not always read the list in real time, direct emails work best. 73, Eric Moderator, COO, etc. /elecraft.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
Re: [Elecraft] Measuring SWR (Long)
Or 10:1 or even 20:1. However ... there's always a "however" or a "but" ... it doesn't matter. The dielectric constant of air [the insulator between open wire conductors] is very close to 1 whereas it is much larger for various forms of coax. Very high SWR creates very high voltages along the line. The energy storage with high dielectric constants is much higher than with air, and dielectric losses go up dramatically. In prehistoric times when we used vacuum tubes and resonant tank circuits, we coupled power to the line with a 2-3 turn link coil adjacent or in the middle of the resonant tank. If the line exhibited reactance, it detuned the tank which we just retuned to resonance ["Dip the plate, increase the coupling, repeat"]. The PA tank circuit became a thoroughly mis-named "antenna tuner." It didn't matter what the SWR was on the open wire transmission line, and in fact no one paid any attention to it. Then flexible coaxial cable was invented. It was much more convenient than open wire line, however in reasonable physical sizes, it had very low characteristic [surge] impedances ... 50 and 75 ohm impedances were the result and now, SWR mattered. The dielectric constant inside the cable was very much higher, and the higher voltages from high SWR resulted in much higher dielectric losses. Then, someone invented the Pi-network [for all of you with fingers poised over the keyboard to pounce on my description of history, relax and breath deeply. I'm making some of the non-technical stuff up to help hold your attention]. The Pi-network would transform the 50 or 75 ohm impedance at the end of the coax to the several thousand ohm plate circuit impedance of the PA stage and power would flow to the antenna unimpeded. It was at this point that sales of SWR indicators soared, SWR became a household abbreviation in the ham community, and an SWR of 1.000:1 became the Nirvana of ham radio. It has been thus ever since. As electronics progressed [?] from the vacuous to the solid state, SWR took on an enhanced importance since the solid state was far less tolerant of overvoltage and energy dissipation than the 807's, 813's, and 250TH's of the previous era. The resonant tank circuit faded, amplifiers now feed non-resonant filter networks and expect to see a 50+j0 ohm load ... or else! This made open wire transmission lines much more difficult to use, requiring some way to adapt a PL259 to connect them to the radio which is both mechanically and electrically hard, and sparked the incorporation of "SWR Alarms" into our radios. It also spawned the "balun," a mysterious device that may be of alien origin since no one seems to know exactly what it does or how it does it. I hope this helps. [:-) 73, Fred ["Skip"] K6DGW ex KN6DGW 1953 Sparks NV DM09dn Washoe County On 4/9/2019 7:21 PM, W2xj wrote: I agree except that even at 500KW a 2:1 or greater is the norm with open wire line. Sent from my iPhone On Apr 9, 2019, at 19:10, Fred Jensen wrote: Well, the reflected power is created by a "virtual transmitter" at the feedpoint of the antenna and heads down the coax which has a surge impedance of Z0 ohms. It meets the SO-239 at the TX and sees an impedance of Z1, the impedance presented by the PA and output filters. If Z1=Z0, the power is dissipated as heat in the PA and associated RF circuitry. If Z1<>Z0, some is dissipated and some is reflected, where some is radiated, and some is reflected [virtual transmitter again]. Ad infinitum, and when forever is over, it is all gone and everyone lives happily ever after. SWR and all the associated measuring equipment and concern with it only became an issue when: 1) Coax replaced parallel lines and; 2) Resonant output circuits were replaced by solid state amplifiers with non-resonant filters. When I sat for the Extra in early 1956, the only question that involved standing waves was one about how Lecher Lines could be used to measure transmitter frequency. It's important today but calculating it hasn't changed. At 10 W, a 2:1 SWR will probably work ok. At 1500 W, a solid state amplifier may not be happy with the voltages developed at its output connector. 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County __ 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
Re: [Elecraft] My "MFJ Posting"
Since when did nationality = race? Why do you assume Ken’s comment was based on how Martin looks? He may have never seen a photo of him. I certainly haven’t, that I can recall. His name sounds like it’s Asian. Is his ethnicity Chinese, Japanese, Korean? I have no idea. Ken may have assumed, I gather incorrectly, that he was an immigrant from one of those nations. Each of those nations certainly have different cultures, with different sets of cultural norms. Ken made a very awkward statement. Not one I would make. But, I think branding it as racism is more in the eye of the beholder then the pen of the author. 73 de Carl N8VZ Sent from my iPhone === Carl Jón Denbow, N8VZ 17 Coventry Lane Athens, Ohio 45701-3718 c...@n8vz.com www.n8vz.com EM89wh IRLP 4533 Echolink 116070 PSK and JT65 Forever! === > On Apr 10, 2019, at 11:55 AM, Scott Manthe wrote: > > This is what Ken said: > Perhaps the matter stems from the nationality of MFJ's owner and a > different set of values. > > He doesn't mention "culture" at all. He mentions nationality, but since > Martin Jue is an American, born in Mississippi, what is he talking about? Ken > is saying that Jue doesn't "look" like an American and has different values > because of the way he looks. Isn't that racist? If that's not real racism, > then what is? Ken didn't call him a pejorative name, but he did assume the > Martin has different values based on the way he looks. Isn't that ugly enough > for you? > > 73, > Scott N9AA > >> On 4/10/19 9:20 AM, Carl Jón Denbow wrote: >> What gets me is that Ken was not commenting on a race but a culture. He was >> completely wrong in his assessment of the culture to which the head of MFJ >> belonged, but that’s another issue. It should not have been implied he was >> a racist for that comment. An apology is due, IMHO. The word “racist” is >> thrown around too frequently today in ways that are on the verge of >> rendering the word meaningless. At that point real racists take cover under >> the umbrella thus created by the misuse of the term. That’s very >> unfortunate, because real racism is hideous and needs to be forcefully >> countered and confronted everywhere it raises its ugly head. >> >> 73, >> >> Carl >> >> Sent from my iPhone >> === >> Carl Jón Denbow, N8VZ >> 17 Coventry Lane >> Athens, Ohio 45701-3718 >> >> c...@n8vz.com >> www.n8vz.com >> EM89wh >> >> IRLP 4533 Echolink 116070 >> >> PSK and JT65 Forever! >> === >> On Apr 9, 2019, at 4:34 PM, Joan via Elecraft wrote: Thank you, Jim N4ST, for expressing something which I had become afraid to (having been stung by wasps too many times) 73, Joan KX2CW Darmok and Jalad at Tanagra, said Piglet. Shaka, when the walls fell, said Pooh. On Apr 8, 2019, at 10:41, Jim - N4ST wrote: Ken, The Internet has created a mob of hyper-sensitive hype-critical keyboard warriors. Any comment, including this one is likely to bring on the slings and arrows. With respect to ham gear, yes, roughly speaking you get what you pay for, but sometimes marginal performance is much better than no performance. Most of the MFJ stuff I have purchased has served the purpose, especially in my younger years when more expensive alternatives were out of reach. I also drive Fords & Chevys and not Range Rovers and Mercedes. ___ 73, Jim - N4ST -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Ken G Kopp Sent: Monday, April 8, 2019 08:16 To: Elecraft Subject: [Elecraft] My "MFJ Posting" I am dismayed at the view some took of my posting. I intended absolutely no racial or eletist content ... in any way ... and apologize to anyone who read it that way. 73 ! Ken Kopp - K0PP __ 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 >>> __ >>> 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 >> __ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm
Re: [Elecraft] Measuring SWR (Long)
A typical transmitter does not reverse terminate the transmission line with its characteristic impedance, so most of the reflected power gets re-reflected as forward power. Reflected power isn't necessarily lost power. At least at lower frequencies, it is likely to present a much higher impedance. A final that did accurately terminate the line would be rather inefficient. A more important issue with SWR is high SWRs can cause clipping (you need a larger voltage swing if the load is higher (assuming purely resistive for the moment), or take it outside the safe operating area of the output devices. Those may cause problems at quite low SWRs, but they actually depend on the complex impedance, so on some parts of the Smith chart circle you may be completely safe, but on others, you might kill the finals. On 09/04/2019 22:39, Roger D Johnson wrote: For an interesting discussion..."What happens to the power that's reflected?" __ 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
Re: [Elecraft] SWR - does it matter?
And then use the lowest loss feedline one can afford and install. This minimizes the increased loss due to SWR. Bob, K4TAX Sent from my iPhone > On Apr 10, 2019, at 11:13 AM, Ignacy wrote: > > Assuming that the correct load is 50 Ohms, load with SWR of 1.5:1 could be 33 > Ohm or 75 Ohm. Or something more complex. > > The load of 33 Ohm would cause bigger dissipation and the load of 75 Ohm > less dissipation but also less power. > > Three options here. First, spend hrs/days optimizing your antennas. Second, > use antenna tuner. Third, accept inefficiencies. Personally, I would not > consider a solid-state amp without a built-in tuner. > > Ignacy, NO9E > > > > -- > Sent from: http://elecraft.365791.n2.nabble.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 > __ 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
[Elecraft] Vibroplex Code Warrior JR
Not sure who had the modification for the Vibroplex Code Warrior JR posted but THANKS! I removed the screws holding the paddles in place and replaced them with brass screws and washers (I used nuts as the hardware store did not have brass washers) and I now like the paddle. I also used some nail polish (wifes…) on the bottom to hold them in place as they are “slightly loose” to give me a good feel. I also noticed I “had” washers underneath the paddle as well. It has been a frustrating experience with the dits on my Code Warrior JR since new but replacing both screws and adding washers gave me a new paddle. de KG9H __ 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
Re: [Elecraft] SWR - does it matter?
Assuming that the correct load is 50 Ohms, load with SWR of 1.5:1 could be 33 Ohm or 75 Ohm. Or something more complex. The load of 33 Ohm would cause bigger dissipation and the load of 75 Ohm less dissipation but also less power. Three options here. First, spend hrs/days optimizing your antennas. Second, use antenna tuner. Third, accept inefficiencies. Personally, I would not consider a solid-state amp without a built-in tuner. Ignacy, NO9E -- Sent from: http://elecraft.365791.n2.nabble.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
Re: [Elecraft] SWR - does it matter?
If you want your antenna match to be correct use aScopeMatch as I describe on my 630M web-site. Thanks 73 Ken K5DNL www.k5dnl.com On Wednesday, April 10, 2019, 9:03:48 AM CDT, Andy Durbin wrote: As a counter to those who are asserting that SWR 1.5:1 is a good enough match for an antenna system I offer measured data for the KPA500. At 14.005 MHz my KPA500, when connected to a 1.44:1 SWR load (R37, X9), had a PA dissipation of over 500 watts when producing 400 watts RF output. When the load was changed to 1.30:1 (R39, X3) the PA dissipation was about 410 watts. When the load was changed to SWR 1.07:1 (R49, X3) the PA dissipation was reduced to under 400 watts. (The plots are far more informative than a text description but I can't post them here). If you don't mind your KPA500 running hot, and are prepared to accept it shutting down with PA DISS fault, then 1.5:1 SWR may be good enough for you. I'd rather know the complex impedance of the antenna system load and avoid loads that result in high PA dissipation. 73, Andy, k3wyc __ 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 __ 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
[Elecraft] SWR - does it matter?
As a counter to those who are asserting that SWR 1.5:1 is a good enough match for an antenna system I offer measured data for the KPA500. At 14.005 MHz my KPA500, when connected to a 1.44:1 SWR load (R37, X9), had a PA dissipation of over 500 watts when producing 400 watts RF output. When the load was changed to 1.30:1 (R39, X3) the PA dissipation was about 410 watts. When the load was changed to SWR 1.07:1 (R49, X3) the PA dissipation was reduced to under 400 watts. (The plots are far more informative than a text description but I can't post them here). If you don't mind your KPA500 running hot, and are prepared to accept it shutting down with PA DISS fault, then 1.5:1 SWR may be good enough for you. I'd rather know the complex impedance of the antenna system load and avoid loads that result in high PA dissipation. 73, Andy, k3wyc __ 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
Re: [Elecraft] My "MFJ Posting"
What gets me is that Ken was not commenting on a race but a culture. He was completely wrong in his assessment of the culture to which the head of MFJ belonged, but that’s another issue. It should not have been implied he was a racist for that comment. An apology is due, IMHO. The word “racist” is thrown around too frequently today in ways that are on the verge of rendering the word meaningless. At that point real racists take cover under the umbrella thus created by the misuse of the term. That’s very unfortunate, because real racism is hideous and needs to be forcefully countered and confronted everywhere it raises its ugly head. 73, Carl Sent from my iPhone === Carl Jón Denbow, N8VZ 17 Coventry Lane Athens, Ohio 45701-3718 c...@n8vz.com www.n8vz.com EM89wh IRLP 4533 Echolink 116070 PSK and JT65 Forever! === > On Apr 9, 2019, at 4:34 PM, Joan via Elecraft > wrote: > > Thank you, Jim N4ST, for expressing something which I had become afraid to > (having been stung by wasps too many times) > > 73, > Joan KX2CW > > Darmok and Jalad at Tanagra, said Piglet. > Shaka, when the walls fell, said Pooh. > >> On Apr 8, 2019, at 10:41, Jim - N4ST wrote: >> >> Ken, >> >> The Internet has created a mob of hyper-sensitive hype-critical keyboard >> warriors. >> Any comment, including this one is likely to bring on the slings and arrows. >> >> With respect to ham gear, yes, roughly speaking you get what you pay for, >> but sometimes marginal performance is much better than no performance. >> Most of the MFJ stuff I have purchased has served the purpose, especially in >> my younger years when more expensive alternatives were out of reach. >> I also drive Fords & Chevys and not Range Rovers and Mercedes. >> >> ___ >> 73, >> Jim - N4ST >> >> -Original Message- >> From: elecraft-boun...@mailman.qth.net On >> Behalf Of Ken G Kopp >> Sent: Monday, April 8, 2019 08:16 >> To: Elecraft >> Subject: [Elecraft] My "MFJ Posting" >> >> I am dismayed at the view some took of my posting. I intended absolutely no >> racial or eletist content ... in any way ... and apologize to anyone who >> read it that way. >> >> 73 ! >> >> Ken Kopp - K0PP >> __ >> 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 > __ > 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 __ 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
