Re: [Elecraft] KPA500 AC power
Unless you are having a problem, save your money. I have two KPA500’s, one plugged into a 220V line at my main house and the other into a 110V line at my beach house and have never seen a difference in performance. In addition, on a number of contests Dx’peditions, were I have my K3s, KPA500 & laptop plugged into the same 110V line, I have not had a problem. Happy Holidays Irwin KD3TB On Wed, Dec 12, 2018 at 7:14 PM Tom Berry wrote: > Is there any advantage to use 220 V over 110 V on the KPA500? > > Is it worth having an electrician come to the house and install a 220 V > outlet for it? > > > Thanks > > Tom AA4VV > > __ > 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 idar...@gmail.com > -- Irwin KD3TB __ 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] KPA500 AC power
I would only agree with whoever mentioned the possibility of flickering lights. If you're a CW operator it can be a distraction...if your house wiring can't handle it. Been there... John K7FD -From: "Irwin Darack" To: "Tom Berry" Cc: elecraft@mailman.qth.net Sent: Thursday December 13 2018 5:14:43AM Subject: Re: [Elecraft] KPA500 AC power Unless you are having a problem, save your money. I have two KPA500’s, one plugged into a 220V line at my main house and the other into a 110V line at my beach house and have never seen a difference in performance. In addition, on a number of contests Dx’peditions, were I have my K3s, KPA500 & laptop plugged into the same 110V line, I have not had a problem. Happy Holidays Irwin KD3TB On Wed, Dec 12, 2018 at 7:14 PM Tom Berry wrote: > Is there any advantage to use 220 V over 110 V on the KPA500? > > Is it worth having an electrician come to the house and install a 220 V > outlet for it? > > > Thanks > > Tom AA4VV > > __ > Elecraft mailing list > Home: http://www.qsl.net [1] > Please help support this email list: Message delivered to macymonk...@charter.net Links: -- [1] http://mailman.qth.net/mailman/listinfo/elecraft http://mailman.qth.net/mailman/listinfo/elecraft /> > Help: http://mailman.qth.net/mailman/listinfo/elecraft http://mailman.qth.net/mailman/listinfo/elecraft /> Help: 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] [KAT500] Odd KAT500 Behavior
I am using an early KAT500 with a K3S. When using WSPR in band-hopping mode at 5w, WSJT-X 2.0 commands a band change and transmit, the K3S starts transmitting, then stops, changes bands, then changes back to the original band, say 40 meters. I think this part is a WSJT problem, and has been reported. Now the K3 is on 40m. If I press the TUNE button in WSPR, the SWR meter shows a high SWR and relays click in the KAT500. If I press TUNE again, the swr is good. The KAT500 is configured to follow the K3 vfo, so why is the KAT500 retuning? If the K3 shows 40m, why wouldn't the KAT500 have the proper tuning solution? It is properly cabled with auxbus cables between the K3, KAT500, and KPA500 in that order (the KPA500 is off). The KAT3 is in bypass mode. I don't think this is an rf problem because I regularly use the KPA500 with no signs of rf getting into anything. This seems very odd. All firmware is current. Any ideas? 73 Eric WD6DBM Sent from Yahoo Mail on Android __ 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] [K3] K3 50W TX Calibration Question
Why does the KPA3 have to be set to NOR instead of FN1 when doing a 50W TX calibration? Just curious. 73 Eric WD6DBM Sent from Yahoo Mail on Android __ 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] [KAT500] Odd KAT500 Behavior
Eric, Are you operating with the KAT500 in AUTO mode? If so, after "training" the tuner across the band of interest with any one antenna, change it to MAN mode and it will not try to re-tune. As you said, the KAT500 follows the K3 VFO, so there should not be a need for any retuning. The problem is that the forward and reflected powers cannot be read simultaneously. So if the forward power is read when the power is low, and the reflected power is read when the power is higher, an erroneous SWR calculation will result. 73, Don W3FPR On 12/13/2018 9:19 AM, eric norris via Elecraft wrote: I am using an early KAT500 with a K3S. When using WSPR in band-hopping mode at 5w, WSJT-X 2.0 commands a band change and transmit, the K3S starts transmitting, then stops, changes bands, then changes back to the original band, say 40 meters. I think this part is a WSJT problem, and has been reported. Now the K3 is on 40m. If I press the TUNE button in WSPR, the SWR meter shows a high SWR and relays click in the KAT500. If I press TUNE again, the swr is good. The KAT500 is configured to follow the K3 vfo, so why is the KAT500 retuning? If the K3 shows 40m, why wouldn't the KAT500 have the proper tuning solution? It is properly cabled with auxbus cables between the K3, KAT500, and KPA500 in that order (the KPA500 is off). The KAT3 is in bypass mode. I don't think this is an rf problem because I regularly use the KPA500 with no signs of rf getting into anything. This seems very odd. All firmware is current. Any ideas? 73 Eric WD6DBM __ 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] [KAT500] Odd KAT500 Behavior
Just went through the setup for WSPR on 160M - 6M for my station, K3S, KAT500, etc. I have the KAT500 in MAN mode and it switches bands correctly. I didn't see any issues at 5 watts transmit. Why is it re-tuning? Are you operating the KAT500 in the AUTO mode? Just go through each band using the TUNE mode on the K3S and with the antenna of choice and allow the KAT500 to resolve a match for the specific WSPR frequency. Then operate the KAT500 in MAN mode. Performs as it should for me. 73 Bob, K4TAX On 12/13/2018 8:19 AM, eric norris via Elecraft wrote: I am using an early KAT500 with a K3S. When using WSPR in band-hopping mode at 5w, WSJT-X 2.0 commands a band change and transmit, the K3S starts transmitting, then stops, changes bands, then changes back to the original band, say 40 meters. I think this part is a WSJT problem, and has been reported. Now the K3 is on 40m. If I press the TUNE button in WSPR, the SWR meter shows a high SWR and relays click in the KAT500. If I press TUNE again, the swr is good. The KAT500 is configured to follow the K3 vfo, so why is the KAT500 retuning? If the K3 shows 40m, why wouldn't the KAT500 have the proper tuning solution? It is properly cabled with auxbus cables between the K3, KAT500, and KPA500 in that order (the KPA500 is off). The KAT3 is in bypass mode. I don't think this is an rf problem because I regularly use the KPA500 with no signs of rf getting into anything. This seems very odd. All firmware is current. Any ideas? 73 Eric WD6DBM Sent from Yahoo Mail on Android __ 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 rmcg...@blomand.net __ 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] CW Decode and Preamp?
I'll take a look at both of those suggestions. I do try to have the decode around 3 or 4, but code that'll decode with the preamp off doesn't even make the CWT bar flicker with it on. So there's more at work here than signal strength. That's why I asked what I did. But I'll try to work on technique and see if it's just me being thumb-fingered or something. On Thu, Dec 13, 2018 at 2:44 AM Gerald Manthey wrote: > Gwen > > If you hold down the Text Dec button (CWT) button what is your THR set to. > This is what you adjust for sensitivity for the decode. > > Mine is usually set to around 3 and I can decode from s4 to s9. If the > signal is real weak I usually Adjust the RF gain more and turn the THR down > to 2 and it will decode fine. > > I usually run with my RF Gain set at 3 o’clock all the time. > > There is a program that is called MRP40 that decodes almost no matter what > your radio is set to. One of the best decodeer programs out there. But it > cost. > > I used it at first and after using that and getting on the air it kinda > self taught me morse code. Hihi. > > Ok let me know if you have any other questions or if I can help. I hope I > understood the questions right and this helps. > > Thanks > > Gerald KC6CNN > > > > > > > > *From: *Gwen Patton > *Sent: *Wednesday, December 12, 2018 7:23 PM > *To: *elecraft@mailman.qth.net > *Subject: *[Elecraft] CW Decode and Preamp? > > > > Please forgive me if this is a FAQ. If it is, just point me to where I can > > find the old answer and I won't bring it up again. > > > > I can usually get the CW decode to work if I can clearly hear the signal. > > The CWT bar flashes and the text scrolls, and it gets a lot of characters > > right. BUT... > > > > ...that's only if I have the preamp OFF. > > > > I've tried using the preamp but decreasing the RF gain. I've tried using > > the preamp and the attenuator. I even tried setting a couple of bands to > > only 10db preamplification. But if the preamp is on AT ALL, the decode > > either never gets a "lock" and the CWT bar is flickering randomly (no > > matter what the threshold setting is) with no decode, or the CWT bar is > > solid, no flashing, and there's no decode. > > > > If have the preamp OFF, the same signal will usually decode at least > > somewhat, and sometimes excellently. Most of the time, W1AW can decode > > fairly easily...though FLDIGI and CWGET seem to decode more reliably. > > They'll decode 80-90%, while mush is appearing on the PX3 display lines. > > But at least I get something with the preamp off. > > > > But there's just some times when the signal is weaker and I can't get the > > threshold to crack without the preamp. But then I get no decode at all. > > > > Am I doing something WRONG? Is there some step that I'm not understanding? > > Heck, I've seen past entries in the list where some have said they can't > > get decode unless the preamp is ON! > > > > Or is there some known issue with preamp + decode that I haven't seen? Mind > > you, my antenna, while not fantastic, is adequate for me to get to Europe > > on FT8 at 35 watts. I even got from Philly to Fargo on 50w FT8 on 30 > > meters, using an indoor magnetic loop I built. So it's not my antennas. I > > have signal, but paradoxically, when the signal is strengthened by the > > preamp, I get lower decode performance. I'd expect that in high-noise > > conditions -- amplifying the noise as well as the signal and hashing them > > both -- but when the noise floor is low and the signal is just made more > > solid with the preamp, I should be able to decode it with the same > > technique as when I use it on a stronger signal without the preamp. > > Shouldn't I? Or am I simply not grasping some fundamental issue? I've read > > the manual, I've read mailing list archive messages, I've experimented with > > my own second rig on a dummy load sending a canned CW message (K2 s/n > 1641). > > > > This will, I hope, be a moot point in a few months. I'm trying to learn to > > copy the CW barebrained instead of using the decoder. (I got rusty from > > when I first learned it back in 1999.) But I want to at least be able to > > check my copy using the decode function if I can until then. Between them, > > maybe I can hold a coherent QSO! > > > > Thanks, > > Gwen, NG3P > > > > -- > > > > -+-+-+-+- > > Jenny Everywhere's Infinite: Quark Time > > http://quarktime.net > > __ > > 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 kc6...@gmail.com > > > -- -+-+-+-+- Jenny Everywhere's Infinite: Quark Time http://quarktime.net __ Elecraft mailing list Home: http://mailman.qth.net/mailm
[Elecraft] 10 dB or 3?
A very unpleasant dinner last night at a restaurant with a reported noise level of 84 db – about the same as a gas engine lawn mower seated at the next table – raised what is probably an elementary question. 3 db is the familiar doubling of power, and in an audio environment is a doubling of acoustic energy, I understand. However, I have read that ten db is what results in an apparent doubling of the sound level as we hear it. Is the difference attributable to something like an AGC circuit in the human auditory system? And as for RF transmitter power, does it take a ten db increase rather than 3 to effect an apparent doubling of audio amplitude in the ears on the other end of the QSO? Never mind the S meter – I mean the actual ability to hear a signal over the noise, or over the QRM. Help, anyone? Ted, KN1CBR __ 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] KPA500 AC power
Make sure the 120v line/outlet is not getting warm. Measure ac voltage with amp off and then in keydown transmit to check voltage drop. I don't have a KPA500 or KPA1500 but did have a 8877 with 4kV PS. It ran at 750ma which is 3000w dc load. That converts to 12.5A at 240v if PS is 100% efficient. At 120v that would run 25A which exceeds rating or No. 12 house wiring. I now have a 1200w sspa that draws 50v-50A (2500w dc). I installed my own 240v using 8-4 wiring bought at Home Depot. I get about 2vac drop when keydown at 1500w RF. I installed a small breaker box in the shack with one dual 20A breaker for 240v and split out two 120v 20A ckts which run my 12v-50A station PS and a 26v MOT repeater PS for my 220-MHz 150w PA. I also have a 1000w 50-MHz sspa powered by 50v-50A switching PS (2500w dc) that uses 240vac. Only run one QRO amp at a time. Running the 8-4 wire from my main load center down thru crawl space under the main floor then back up thru spare bedroom (shack) floor; about 35-foot run. I drilled small holes in floor joists to tie off the cable using wire ties. Crawl space is 4-foot high. Obviously if your house is on concrete slab you would need and alternative. Suggest running outside on house wall with conduit (which can be pvc if cable is sheathed). We have very lax building codes up here so home self-construction is common. Have a licensed electrician do the work if codes require (for insurance coverage). 73, Ed - KL7UW http://www.kl7uw.com Dubus-NA Business mail: dubus...@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] Another preaching to the choir moment.
Short & sweet... I had issues with my K3s that required factory work. Elecraft went the extra mile to resolve them and were far more than fair in doing so. There are few companies that take care of their customers as well as Elecraft. I have said this before, here, and I'll gladly say it again; As long as Elecraft is making radio equipment and following their historic work ethic, I will be a customer for life. 73, Gary KA1J __ 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] [KAT500] Odd KAT500 Behavior
KAT500 is in MANUAL mode 73 Eric WD6DBM On Thu, Dec 13, 2018, 8:26 AM Bob McGraw K4TAX Just went through the setup for WSPR on 160M - 6M for my station, K3S, > KAT500, etc.I have the KAT500 in MAN mode and it switches bands > correctly. I didn't see any issues at 5 watts transmit. > > > __ 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] K3 Suddenly Putting Out Only 25 watts at 100 watts indicated
Ok. You’re right. Must have had my mind on something else. Read too many emails. Merry Christmas. Or you know, whatever?!! Sent from my iPhone ...nr4c. bill > On Dec 12, 2018, at 9:11 PM, Peter Dougherty (W2IRT) wrote: > > This happened to me at the start of CQWW-SSB in October. My K3s is finally > enroute back home after a 6 week stay in the Elecraft Repair Department with > a blown FET in the HPA, cause unknown. And I know I've been told I'm not the > only one to suffer this failure, and it sounds like this is now a known > issue. > > Does anybody have an idea as to what could be causing these FETs to fail, or > steps to consider to lessen the chances of it happening? I can't speak for > anybody else, but I baby the heck out of my gear and was shocked to discover > it failed, when feeding directly into a KPA-1500. > > > Regards, > Peter Dougherty, W2IRT > > -Original Message- > From: elecraft-boun...@mailman.qth.net > [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Wes Stewart > Sent: Wednesday, December 12, 2018 4:55 PM > To: elecraft@mailman.qth.net > Subject: Re: [Elecraft] K3 Suddenly Putting Out Only 25 watts at 100 watts > indicated > > If you have another receiver, run a two-test and listen to the K3 output in a > narrow BW. Ideally, the two tones will be considerably stronger than the > first > pair of sidebands. > > I suspect they won't be, you'll have a lot more than two and you have a blown > FET in the HPA. > > Wes N7WS > > >> On 12/12/2018 12:47 PM, N4ZR wrote: >> Transmitted on my K3 for the first time since the 10-meter contest, and it >> is >> only showing 25 watts out on the built-in meter into a dummy load. Power >> output setting of the K3 is 100W, and same results seen on all bands. What >> could possibly be going on here? Back to Watsonville? >> >> The cruel karma of it all is that *yesterday* I ordered a KPA-1500. >> > > __ > 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 li...@w2irt.net > > __ > 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 n...@widomaker.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] K3 Suddenly Putting Out Only 25 watts at 100 watts indicated
It would be nice to know what conditions caused this FET failure. Is there an easy way to know when this failure occurs other than getting crappy audio reports? John KK9A Peter Dougherty (W2IRT) wrote: This happened to me at the start of CQWW-SSB in October. My K3s is finally enroute back home after a 6 week stay in the Elecraft Repair Department with a blown FET in the HPA, cause unknown. And I know I've been told I'm not the only one to suffer this failure, and it sounds like this is now a known issue. Does anybody have an idea as to what could be causing these FETs to fail, or steps to consider to lessen the chances of it happening? I can't speak for anybody else, but I baby the heck out of my gear and was shocked to discover it failed, when feeding directly into a KPA-1500. Regards, Peter Dougherty, W2IRT -Original Message- From: elecraft-bounces at mailman.qth.net [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Wes Stewart Sent: Wednesday, December 12, 2018 4:55 PM To: elecraft at mailman.qth.net Subject: Re: [Elecraft] K3 Suddenly Putting Out Only 25 watts at 100 watts indicated If you have another receiver, run a two-test and listen to the K3 output in a narrow BW. Ideally, the two tones will be considerably stronger than the first pair of sidebands. I suspect they won't be, you'll have a lot more than two and you have a blown FET in the HPA. Wes N7WS __ 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] [KAT500] Odd KAT500 Behavior
It seems that the KAT may not be getting fresh band info - if it did you would be hearing relays being set before the K3 transmitted. The KPA500 is listening to the same Band signals as the KAT (but not the Auxbus data), so I would turn on the KPA500, leave it in standby, and watch the display and listen to its relays to see if it changes bands when the K3 does. I think the key here is to determine exactly what the WSPR code is sending the K3. Is it also sending data to the KAT500? If so that stream would also be telling. If the computer is commanding the K3 to go into transmit before all the commands have been received it could cause a situation just like you describe. It might be up to the software author to fix this situation. 73! Jack, W6FB > On Dec 13, 2018, at 6:19 AM, eric norris via Elecraft > wrote: > > I am using an early KAT500 with a K3S. When using WSPR in band-hopping mode > at 5w, WSJT-X 2.0 commands a band change and transmit, the K3S starts > transmitting, then stops, changes bands, then changes back to the original > band, say 40 meters. I think this part is a WSJT problem, and has been > reported. Now the K3 is on 40m. If I press the TUNE button in WSPR, the SWR > meter shows a high SWR and relays click in the KAT500. If I press TUNE > again, the swr is good. > The KAT500 is configured to follow the K3 vfo, so why is the KAT500 retuning? > If the K3 shows 40m, why wouldn't the KAT500 have the proper tuning > solution? It is properly cabled with auxbus cables between the K3, KAT500, > and KPA500 in that order (the KPA500 is off). The KAT3 is in bypass mode. I > don't think this is an rf problem because I regularly use the KPA500 with no > signs of rf getting into anything. This seems very odd. All firmware is > current. Any ideas? > 73 Eric WD6DBM > > Sent from Yahoo Mail on Android > __ > 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 jackbrin...@me.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] 10 dB or 3?
Most human perception is logarithmic. A change in OVERALL LOUDNESS of about 10 dB is perceived as twice (or half) as loud. Changes in SIGNAL TO NOISE RATIO as small as 1 dB can be the difference between copy or not. This is true for music as well as speech or CW. When mixing live sound with multiple mics on instruments and voices, once balance is achieved, very small changes in the gain for any mic are usually required to stay in balance. 73, Jim K9YC On 12/13/2018 9:16 AM, Dauer, Edward wrote: A very unpleasant dinner last night at a restaurant with a reported noise level of 84 db – about the same as a gas engine lawn mower seated at the next table – raised what is probably an elementary question. 3 db is the familiar doubling of power, and in an audio environment is a doubling of acoustic energy, I understand. However, I have read that ten db is what results in an apparent doubling of the sound level as we hear it. Is the difference attributable to something like an AGC circuit in the human auditory system? And as for RF transmitter power, does it take a ten db increase rather than 3 to effect an apparent doubling of audio amplitude in the ears on the other end of the QSO? Never mind the S meter – I mean the actual ability to hear a signal over the noise, or over the QRM. Help, anyone? Ted, KN1CBR __ 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] K3 Suddenly Putting Out Only 25 watts at 100 watts indicated
That's how I discovered it. Normally I can work anybody I hear, but at the start of WW I was working one in ten that I called in S&P, and after one long, difficult exchange I was told I sounded terrible. The day before I'd been working a Dxpedition on CW and FT8 and no problem, until I started calling on 15m FT8. The op was begging, I was running over 1300W, signals were strong and I couldn't make a Q for love or money with 'em. I chalked it up to one-way propagation but I suspect that was about the time the failure occurred. I was feeding the KPA-1500 with whatever power it needed to get about 1300-1400W out. Likewise, for CQWW, I was doing the same. Regards, Peter Dougherty, W2IRT DXCC Card Checker/CQ-WAZ Checkpoint www.facebook.com/W2IRT -Original Message- From: j...@kk9a.com [mailto:j...@kk9a.com] Sent: Thursday, December 13, 2018 2:04 PM To: elecraft@mailman.qth.net Cc: li...@w2irt.net Subject: re: [Elecraft] K3 Suddenly Putting Out Only 25 watts at 100 watts indicated It would be nice to know what conditions caused this FET failure. Is there an easy way to know when this failure occurs other than getting crappy audio reports? John KK9A Peter Dougherty (W2IRT) wrote: This happened to me at the start of CQWW-SSB in October. My K3s is finally enroute back home after a 6 week stay in the Elecraft Repair Department with a blown FET in the HPA, cause unknown. And I know I've been told I'm not the only one to suffer this failure, and it sounds like this is now a known issue. Does anybody have an idea as to what could be causing these FETs to fail, or steps to consider to lessen the chances of it happening? I can't speak for anybody else, but I baby the heck out of my gear and was shocked to discover it failed, when feeding directly into a KPA-1500. Regards, Peter Dougherty, W2IRT -Original Message- From: elecraft-bounces at mailman.qth.net [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Wes Stewart Sent: Wednesday, December 12, 2018 4:55 PM To: elecraft at mailman.qth.net Subject: Re: [Elecraft] K3 Suddenly Putting Out Only 25 watts at 100 watts indicated If you have another receiver, run a two-test and listen to the K3 output in a narrow BW. Ideally, the two tones will be considerably stronger than the first pair of sidebands. I suspect they won't be, you'll have a lot more than two and you have a blown FET in the HPA. Wes N7WS __ 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] CW Decode and Preamp?
Gwen Patton writes: I do try to have the decode around 3 or 4, but code that'll decode with the preamp off doesn't even make the CWT bar flicker with it on. I copy code in my head but have played with the CW decoder on my KX2 for amusement and also at our FD station so the others could see what was being sent and received. A couple were interested in learning the code. One fella brought an MFJ CW reader. We could not get a "solid copy" on either of them except on very strong signals. With typical band conditions and even sorta weak QRP stations, I can get maybe 80% copy - not bad, but not 100% copy. I've also found the threshold around 3-5 to be the best, like you, though does tend to change from station to station and day-to-day depending upon band conditions. So there's more at work here than signal strength. The advice on better copy without excessive RF gain is valid. However, you do need that extra gain to properly drive the CWT and decoder on most signals, as you noted, even if the signal-to-noise ratio is compromised. Tuning and filtering is also important. I usually set my CW filter at 25-30Hz for best decode and push the button that sets the VFO to the proper offset to center the CWT ... then tweak the VFO just a bit for best decode. Lastly, I have found the decode to work better at 18-20 wpm or higher; slower code speeds is prone to triggering on noise. I would recommend tuning where there are no signals - just noise - and set things for no false decode from the noise, then tune to the station you want to decode. Hope the above helps. The decoder can be a good tool for helping you learn the code, just realizing you will seldom achieve 100% copy on the decoder (and sometimes even by ear!). I admire you for your desire to learn the code. It takes a lot of nerve to get on the air for those first few QSOs. We all remember our first QSOs. And as we'll all tell you, the best way to improve your CW is to get on the air. Most CW ops are more than willing to match your code speed (except in a contest maybe) to give you an enjoyable QSO and help you along. Sorry for the long reply, but hopefully helpful to you and some others. 72, Paul NA5N PS - email me if you'd like to arrange a sked on the air. Will use my straight key and any speed is fine. __ 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] K3 Suddenly Putting Out Only 25 watts at 100 watts indicated
If you see low power it's a clue. I operate my K3S + KPA500 as a 500W transceiver, except when I'm running IMD tests, so the last time it happened I was notified of bad audio. The previous times the wattmeter or IMD tests were the clues. Wes N7WS On 12/13/2018 12:03 PM, j...@kk9a.com wrote: It would be nice to know what conditions caused this FET failure. Is there an easy way to know when this failure occurs other than getting crappy audio reports? John KK9A __ 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] 10 dB or 3?
It's been 50 years since I worked in the acoustic labs at Boeing where I posed the same question. One of the specialists in the passenger accommodation section of the lab explained it this way: the human ear is a SUBJECTIVE and dynamic instrument. In other words, the perception of sound pressure level (SPL) is a function of environment, how a person feels (is the person ill or have a runny nose, etc.), the listeners temperament (is he happy or upset), the nature of the sound (does the listener like the sound or does he find it annoying), how much has the listener had to drink, etc. As for the dynamic aspect, depending on the environment, you may hear a particular sound one way but a bit differently a moment later, depending on the above factors. Another factor is that sound can be much like water leaking into a boat. Both the water and SPL increases over time depending on the opening through which the water or sound enters a space. That type of sound can be measured with instruments but difficult to assess by ear. Sound in a restaurant can be much like water in a boat, people tend to talk louder which increases the overall SPL which causes them to talk even louder. In short, the rule of thumb is that it takes about a 10 dB increase in SPL for a person to perceive a doubling in the level of the sound. 3dB is almost imperceptible with most any kind of background noise. On a tangential note, during the late 60s the Super Sonic Transport (SST) program was in progress and NASA conducted an extensive series of tests to determine objective and subjective aspects of sonic booms. The tests were conducted at Edwards Air Force Base in California over a three month period. Boeing, Lockheed, and other institutes participated. The base was building additional housing at the time so several of the new structures were used for the tests. Three of them were fitted out like regular homes with carpeting, window shades and curtains, furniture, etc., and a couple of the houses were configured more like offices or large department stores. Some of the homes had people in them and others did not. All of the buildings were extensively instrumented, both inside and out. All of my transducers were mounted on the outside of the buildings and my recording equipment was in a double garage of one of the houses. In my building, the garage door had been replaced with a large plate glass window to simulate a store front. The mounting assembly for the glass was changed from time to time to test various mounting designs. The subjective part of the test was done with people from the local communities who sat in various rooms and filled out forms designed to rate the effects of the sounds they heard. The sonic booms were generated by F104, B58, B70, and the then new SR71/YF12 aircraft. During some of the subjective tests, a KC135 (Boeing 707) airplane was used to simulate takeoff or low fly over sounds near airports. I never read the final report(s) of the tests but a few preliminary reports made the rounds. In the case of the subjective tests, people were all over the map. In many cases, people would give radically different scores for identical tests days or weeks apart. The objective tests often produced predictable results but there were times when repeat tests produced big surprises. Temperature, humidity, wind, and even doors open of closed, made noticeable differences in the measured data. For a quick look, we taped a ball point pen to the center of the large window and mounted a paper plate on the face of a clock so the plate was driven by the second hand. When the boom hit, the pen would produce a trace on the plate showing the displacement of the window. Some of the test were done with the garage being "tuned" by judiciously opening a door. A given aircraft would hit us with a boom then the door would be readjusted and the same aircraft would duplicate the boom minutes later. The difference could be startling. During one series of identical flights the first boom displaced the window 15mm but the second boom produced a displacement of 155mm. This type of testing is very expensive so, in an attempt to reduce the costs a ten foot diameter exponential horn which was mounted on a trailer. To test the efficacy of this device, the trailer was placed near one of the houses then two positive pressure pulses of gas were produced to simulate a sonic boom. The people in the house were told the boom was from an aircraft and asked to rate it in the usual way. (A sonic boom consists of a positive pressure spike followed by a negative spike. The amplitude, shape, and timing of the spike is a function of the speed and shape of the aircraft though the shape of the spike can be modified by structural and geologic features. The tests with the horn produced only positive spikes but the shape and timing could be adjusted mechanically. One day there w
Re: [Elecraft] K3 Suddenly Putting Out Only 25 watts at 100 watts indicated
Someone suggested performing 2 tone tests. Seems reasonable. I tried that with my K3S into a dummy load and an a RF sample fed to my RSP1 receiver using HDSDR software. I find that it does indeed display the IMD products from the 2 tones. I now need to study the results a bit more to evaluate the test. {Oh, don't forget to set 2 TONE to OFF mode or you'll get a surprise when you jump into that SSB rag chew group. The comments won't be very kind.} 73 Bob, K4TAX On 12/13/2018 1:03 PM, j...@kk9a.com wrote: It would be nice to know what conditions caused this FET failure. Is there an easy way to know when this failure occurs other than getting crappy audio reports? John KK9A Peter Dougherty (W2IRT) wrote: This happened to me at the start of CQWW-SSB in October. My K3s is finally enroute back home after a 6 week stay in the Elecraft Repair Department with a blown FET in the HPA, cause unknown. And I know I've been told I'm not the only one to suffer this failure, and it sounds like this is now a known issue. Does anybody have an idea as to what could be causing these FETs to fail, or steps to consider to lessen the chances of it happening? I can't speak for anybody else, but I baby the heck out of my gear and was shocked to discover it failed, when feeding directly into a KPA-1500. Regards, Peter Dougherty, W2IRT -Original Message- From: elecraft-bounces at mailman.qth.net [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Wes Stewart Sent: Wednesday, December 12, 2018 4:55 PM To: elecraft at mailman.qth.net Subject: Re: [Elecraft] K3 Suddenly Putting Out Only 25 watts at 100 watts indicated If you have another receiver, run a two-test and listen to the K3 output in a narrow BW. Ideally, the two tones will be considerably stronger than the first pair of sidebands. I suspect they won't be, you'll have a lot more than two and you have a blown FET in the HPA. Wes N7WS __ 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 rmcg...@blomand.net __ 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] 10 dB or 3?
Ted, I am not going to comment on the dB aspect, but the XYL and I have had great success in restaurants by asking the staff to turn down the music (or TV or whatever was making electronic sound). In many restaurants, it seems that the staff want to listen to *their* music over the din of patrons voices, and that only makes the situation worse. Lowering the music level will lower the overall noise level considerably. People tend to talk louder in a setting where there is loud audio background - they want to talk with their table partners over the electronic noise. I don't know how to counter the Holiday season when you have "Jingle Bells" or "Grandma got run over by a Reindeer" blasting in your ears - eat and shut up may be to only way to counter it or be branded as Grinch or Scrooge. Of course, there is always the one restaurant patron who has no concept of "inside voices" that becomes an irritant to everyone else. Choose restaurants with carpet instead of hard floors for a further decrease in ambient noise level - soft wall hangings help too. 73, Don W3FPR On 12/13/2018 12:16 PM, Dauer, Edward wrote: A very unpleasant dinner last night at a restaurant with a reported noise level of 84 db – about the same as a gas engine lawn mower seated at the next table – raised what is probably an elementary question. 3 db is the familiar doubling of power, and in an audio environment is a doubling of acoustic energy, I understand. However, I have read that ten db is what results in an apparent doubling of the sound level as we hear it. Is the difference attributable to something like an AGC circuit in the human auditory system? And as for RF transmitter power, does it take a ten db increase rather than 3 to effect an apparent doubling of audio amplitude in the ears on the other end of the QSO? Never mind the S meter – I mean the actual ability to hear a signal over the noise, or over the QRM. Help, anyone? Ted, KN1CBR __ 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 donw...@embarqmail.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] K3 Suddenly Putting Out Only 25 watts at 100 watts indicated
Scroll down to the bottom of this and you will see it was me :-) I have made hundreds of IMD measurements on both my K3 and K3S using the built-in two-tone generator and an SDR-IQ/SpectraVue as a spectrum analyzer. I have a string of power attenuators followed by a step attenuator for calibration purposes. Within its linear range the SDR-IQ is remarkably good. This is a laborious process, sped up a little with the K3 utility and saved instrument states in SpectraVue. One nice thing about this setup is that I can actually record the spectrum display and play it back later for analysis just as if it was live. A guy smarter than I could probably automate this; I put the numbers in an Excel spreadsheet and let do the charting. What you can find doing this is that the IMD is sensitive not only to power and voltage but to frequency. Pick the right frequency and IMD can be -40 dBc, pick the wrong one and it's -20 dBc; same radio, same supply voltage and output power. Wes N7WS On 12/13/2018 3:50 PM, Bob McGraw K4TAX wrote: Someone suggested performing 2 tone tests. Seems reasonable. I tried that with my K3S into a dummy load and an a RF sample fed to my RSP1 receiver using HDSDR software. I find that it does indeed display the IMD products from the 2 tones. I now need to study the results a bit more to evaluate the test. {Oh, don't forget to set 2 TONE to OFF mode or you'll get a surprise when you jump into that SSB rag chew group. The comments won't be very kind.} 73 Bob, K4TAX On 12/13/2018 1:03 PM, j...@kk9a.com wrote: It would be nice to know what conditions caused this FET failure. Is there an easy way to know when this failure occurs other than getting crappy audio reports? John KK9A Peter Dougherty (W2IRT) wrote: This happened to me at the start of CQWW-SSB in October. My K3s is finally enroute back home after a 6 week stay in the Elecraft Repair Department with a blown FET in the HPA, cause unknown. And I know I've been told I'm not the only one to suffer this failure, and it sounds like this is now a known issue. Does anybody have an idea as to what could be causing these FETs to fail, or steps to consider to lessen the chances of it happening? I can't speak for anybody else, but I baby the heck out of my gear and was shocked to discover it failed, when feeding directly into a KPA-1500. Regards, Peter Dougherty, W2IRT -Original Message- From: elecraft-bounces at mailman.qth.net [mailto:elecraft-bounces at mailman.qth.net] On Behalf Of Wes Stewart Sent: Wednesday, December 12, 2018 4:55 PM To: elecraft at mailman.qth.net Subject: Re: [Elecraft] K3 Suddenly Putting Out Only 25 watts at 100 watts indicated If you have another receiver, run a two-test and listen to the K3 output in a narrow BW. Ideally, the two tones will be considerably stronger than the first pair of sidebands. I suspect they won't be, you'll have a lot more than two and you have a blown FET in the HPA. Wes N7WS __ 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 rmcg...@blomand.net __ 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 wes_n...@triconet.org __ 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] KPA500 AC power
I have used my KPA500 on both 110 and 240AC and I can honestly say that I saw no difference in either supply voltage. Mike va3mw > > __ 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] K3 Suddenly Putting Out Only 25 watts at 100 watts indicated
" The previous times ..." - ? Good grief, how many times has this FET failed? Ted W4NZ -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Wes Stewart Sent: Thursday, December 13, 2018 3:09 PM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 Suddenly Putting Out Only 25 watts at 100 watts indicated If you see low power it's a clue. I operate my K3S + KPA500 as a 500W transceiver, except when I'm running IMD tests, so the last time it happened I was notified of bad audio. The previous times the wattmeter or IMD tests were the clues. Wes N7WS On 12/13/2018 12:03 PM, j...@kk9a.com wrote: > It would be nice to know what conditions caused this FET failure. Is there > an easy way to know when this failure occurs other than getting crappy > audio reports? > > John KK9A > __ 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 w...@comcast.net __ 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