Re: [Elecraft] Elecraft CW Net Report for May 3rd 4th, 2009
I could copy Tom on 20, but couldn't break the pileup trying to check in. He might have answered my AC, but there were so many tail enders on top of his replies that I couldn't tell. He was about QSA4. From here it sounded more like a single-frequency DX pileup than a net, Hi! The phone rang after about a dozen tries. From the short list of check ins, it sounds like he didn't hear a lot of stations, but that's 20 meters at times... Wasn't able to get on for the 40 meter net. Ron AC7AC __ 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] Saving K2 VFO modes
wayne burdick wrote: Even though the code is well-documented, I'd want to create theory-of-ops and maintenance documentation before I tried to hand it off to another programmer. This is often necessary for projects where you don't have the luxury of writing everything in an encapsulated, object-oriented language, such as on a PC with virtually unlimited code space. In my experience, most open source software lacks this sort of documentation, so lack of documentation shouldn't be seen as a reason for not opening the source. The only things that should take time are getting copyright clearances if anyone but Elecraft owns the copyright and making the business case for releasing it. On the other hand, I'm a little concerned that such documentation doesn't already exist. When I started in the software industry, one of the first things one was told was that one should document code as though one expected to be run over by a bus, the next day. -- David Woolley The Elecraft list is a forum for the discussion of topics related to Elecraft products and more general topics related ham radio List Guidelines http://www.elecraft.com/elecraft_list_guidelines.htm __ 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] Shortwave filters for K3
Bill, in AM, try tuning 1-2 KHz higher or lower than carrier frequency. Works for me (more highs) cuz I have only a 2.8 KHz filter for other-than-cw modes. 73 Dave W8FGX Guys, Just got done assembling my second K3 and this one has a 13 Khz SNIP -- View this message in context: http://n2.nabble.com/Shortwave-filters-for-K3-tp2778285p2786679.html Sent from the Elecraft mailing list archive at 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] [K3] K3 wonder if list
I wonder if two K3s could be interconnected so as to get two front-panels-full of first and second rcvr controls. Maybe much more. You know, sorta like the old Drake R4/T4X twins I occasionally miss a little, or that homebrew transceiving adapter for the 2B and HT32 which I don't miss at all, only much more capable. Sure, there's a second rcvr available. But I wonder if. 73 Dave W8FGX -- View this message in context: http://n2.nabble.com/K3-%22wonder-if%22-list-tp2786838p2786838.html Sent from the [K3] mailing list archive at 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] K3 - SWR Indication
Take any SWR meter and insert it at different locations along the length of the feeder and you will get different readings. Other than SWR reduction due to cable loss, the SWR meter should read the same SWR regardless of where it is on the coax. Picture the constant SWR circles on a Smith Chart where the SWR stays constant as you change the length of the transmission line. If you add feedline loss, the SWR circle will spiral in towards 1:1 as you continue to increase the feedline length. However, the K3 and an external SWR meter are both electrically so close that they should read the same (assuming comparable quality and properly calibrated SWR meters). I have the same issue in that my K3 SWR reading is always better than the reading I get on my in-line Array Sollutions PowerMaster. Not a big difference though. My K3 may read 1:1 when the PowerMaster reads 1.5:1. I haven't really worried about it since I'm comparing the K3's internal SWR meter to an external $400 meter - and the K3 is happy. Phil - AD5X __ 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] K3 Output
After 5 months use my K3 has developed an output problem. The output varies on tune or key down. If it is set on 100 watts, say on 20 meters, the out put will start at 65 watts. It then goes up to 110 and settles at 100 watts. All this is in a span of about two seconds. It does the same at five watts, or any power. It does the same on any antenna. It is ok at 1 mil through the two meter transverter. There is no device between the K3 and the different antennas. The variation is greater at the higher frequencies but does occur on all bands. Ric AA4SC __ 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] K3 Output
Ric Porter wrote: After 5 months use my K3 has developed an output problem. The output varies on tune or key down. If it is set on 100 watts, say on 20 meters, the out put will start at 65 watts. It then goes up to 110 and settles at 100 watts. All this is in a span of about two seconds. It does the same at five watts, or any power. It does the same on any antenna. It is ok at 1 mil through the two meter transverter. There is no device between the K3 and the different antennas. The variation is greater at the higher frequencies but does occur on all bands. First thing I would do is check it into a dummy load Ric. Does it still do it then? If so, try reloading the firmware and make sure you rewrite the tables. See if that helps. 73 Ian -- Ian J Maude, G0VGS SysOp GB7MBC HB9DRV-9 DX Clusters Member RSGB, GQRP, FISTS K2 #4044 |K3 #455 http://www.amateurradiotraining.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
Re: [Elecraft] K3 - SWR Indication
Phil I agree concerning the swr being the same anywhere on the line but that's not what I said. I said you will get different readings. Now I'm sure there's plenty of reasons why we get these different readings and it's likely due to the meter design but the fact remains. One thing I've learned over the years. Any statement or comment made about antennas and feedlines will soon be refuted by another to prove it incorrect. Now my Smith Chart tells me it's time to take my morning walk. 73 Steve Ellington n...@carolina.rr.com - Original Message - From: Phil Debbie Salas dpsa...@tx.rr.com To: elecraft@mailman.qth.net Sent: Monday, May 04, 2009 7:43 AM Subject: Re: [Elecraft] K3 - SWR Indication Take any SWR meter and insert it at different locations along the length of the feeder and you will get different readings. Other than SWR reduction due to cable loss, the SWR meter should read the same SWR regardless of where it is on the coax. Picture the constant SWR circles on a Smith Chart where the SWR stays constant as you change the length of the transmission line. If you add feedline loss, the SWR circle will spiral in towards 1:1 as you continue to increase the feedline length. However, the K3 and an external SWR meter are both electrically so close that they should read the same (assuming comparable quality and properly calibrated SWR meters). I have the same issue in that my K3 SWR reading is always better than the reading I get on my in-line Array Sollutions PowerMaster. Not a big difference though. My K3 may read 1:1 when the PowerMaster reads 1.5:1. I haven't really worried about it since I'm comparing the K3's internal SWR meter to an external $400 meter - and the K3 is happy. Phil - AD5X __ 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] K3 - SWR Indication
- Original Message - From: Steve Ellington n...@carolina.rr.com It appears that your coax does not exactly match the impedance of your dipole (It rarely does) - Thank you Steve for your comments. I fully accept about a probable mismatch between dipole and coax (and of course the performance of the antenna remains to be seen), also that there are many factors affecting SWR and that sampling at different points along the coax will produce different results if there is reactance in the load. In this case the antenna feeder was connected to the LP100A about 2.5 inches down the line from the ANT 1 socket. To my mind that seems a short length to account for an SWR difference at 7 Mhz as big as 1.2:1 (K3) vs 2.0:1 (LP100A and MFJ 259B). We all need to know what sort of load the rig or the amplifier is looking into and a discrepancy like that is unsettling. All three measuring devices see no reactance and 1.0:1 at 7.145 MHz. What seems to happen is that as one moves up or down in frequency from that point (and the load gains reactance) the K3 indication remains significantly lower than than other two. I doubt if 2.5 inches of coax would account for the difference and the MFJ259B, which agrees with the LP100A, connects to the antenna feeder at exactly the same point as the K3's ANT 1 socket so there is not even that extra 2.5 inches. It leads me to think that maybe my K3 is not measuring SWR as well as it should either due to a fault in my particular one or to the way it is set up to work. 73 to all Geoff G3UCK __ 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] K3 - SWR Indication
Geoff, I experience the same issues between my factory aligned K3/100 (#474) and my LP-100A (aligned by Larry at Telepost, Inc). Firmware 3.11 here as well. Terry, W0FM -Original Message- From: Geoffrey Downs [mailto:geoff...@downs.globalnet.co.uk] Sent: Sunday, May 03, 2009 6:12 PM To: elecraft@mailman.qth.net Subject: [Elecraft] K3 - SWR Indication In the past week I've been tuning and pruning an inverted V dipole I've put up for 40m, fed with coax. The job isn't finished yet but I'm noticing significant differences between SWR readings on my K3 and an external LP100A. For example: At 7.000 MHz the K3 currently shows 1.2:1 and the LP100A 2.00:1. At 7.200 MHz the K3 shows 1.0:1 and the LP100A 1.33:1. Both agree that it's 1.0:1 at 7.145 MHz. My MFJ 259B shows similar readings to the LP100A. The differences seem more than one would expect from stray impedance in the KAT3 as referred to when this subject was brought up on the reflector in January this year. I've not made direct comparisons like this before so I don't know if it's a recent phenomenon with my K3 (S/n 266) or has always been so. The readings were taken with PWR at 15w and the LP100A coupler connected to ANT1 with a back-to-back PL259 adapter. ATU was of course in bypass mode. Firmware 3.11. What do others see? 73 to all Geoff G3UCK __ 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] K3 on-channel strong signal overload?
Oliver I guess Elecraft will have to answer this one. Let us know what they say. Steve Ellington n...@carolina.rr.com - Original Message - From: orbarrett hoosa...@hotmail.com To: elecraft@mailman.qth.net Sent: Monday, May 04, 2009 12:39 AM Subject: [Elecraft] K3 on-channel strong signal overload? Hello all, I just finished operating my K3 from my friend's driveway using a portable dipole on 60M, and wanted to inquire about some incoming signal overload that cropped up. I was joined while ragchewing with some friends on 5371.5 by two other friends locally, one operating HF mobile from the same driveway and another operating from a base rig in the shack (using a backyard dipole antenna). When either of these two friends transmitted on the same channel (at 100W), I observed severe signal breakup in the K3 receive audio. To investigate further, I switched the portable antenna from the K3 to my friend's FT-817 on the same operating table, and no audio breakup was observed under the same conditions. Returning the antenna to the K3, I then got rid of most of the signal breakup by turning on the input attenuator and turning down the RF gain to near minimum. Is it possible that the extremely strong on-channel signal in this case is exceeding the ability of the K3's hardware AGC to protect the A/D converter input? Thanks for any suggestions on this, including anything I may have overlooked. AGC was enabled and both the NB and NR were switched off. I should mention that these conditions of operating portable (with several hams close-in on the same channel) are very demanding, but happen occasionally in certain situations such as for HF Pack operating. I'm also using the rig in HF mobile service, and enjoy it very much. I appreciate any help in advance, Oliver Barrett KB6BA -- View this message in context: http://n2.nabble.com/K3-on-channel-strong-signal-overload--tp2785612p2785612.html Sent from the Elecraft mailing list archive at 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] Send me some noise !
Hi All, You may have noticed the K3 SSB RX audio/noise-character discussion some days ago. I got a lot of very interesting feedback on this,also in direct mails, and some people thought it would be interesting to compare different brands/models in their SSB RX audio/noise character. If you have the possibility to record a very small piece of SSB bandnoise in reasonable (line) quality (2 or 3 seconds would be enough) I would find it very interesting to find out what the differences are between different equipment/brands/models. In the past it seems like all manufacturers have been following their own philosophy as to what sounds good or natural. Amongst all brands there are SSB receivers that are loved because they stand out by their natural voice quality. I'd like to find out why and what's their noise-fingerprint. So please mail me your noise !!! HI SSB bandnoise,any bandwidth,any radio(s),any sound format,few seconds is enough. Very much appreciated! 73' Paul PD0PSB -- View this message in context: http://n2.nabble.com/Send-me-some-noise-%21-tp2787655p2787655.html Sent from the Elecraft mailing list archive at 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] K3 - SWR Indication
Other than SWR reduction due to cable loss, the SWR meter should read the same SWR regardless of where it is on the coax. Some reasons for changes in indicated VSWR as measured at different points along the line: 1) Line loss. As line loss increases, VSWR will show a better reading closer to the source than at the load, irrespective of the line-to-load mismatch; 2) The bridge/directional coupler's designed line Z does not equal the characteristic Z of the line and the load is a complex Z. (Example: Bird 43 with 50-ohm line section being used on a run of 75-ohm line where the line is terminated into a load with a Z value other than 75 ohms); and 3) Line current imbalance. Normally, current on the outer surface of the inner conductor should equal the current on the inside surface of the outer conductor. Current flow on the outside of the outer conductor will cause line imbalance and incorrect VSWR indications, depending on the magnitude of current on the outer surface of the outer conductor. Paul, W9AC __ 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] K3 - SWR Indication
Geoff Try putting a 50 ohm dummy load in line and see if the K3 and your ext. meters read the same swr. This will take reactance and inbalance out of the picture. Steve Ellington n...@carolina.rr.com - Original Message - From: Geoffrey Downs geoff...@downs.globalnet.co.uk To: elecraft@mailman.qth.net Sent: Monday, May 04, 2009 10:14 AM Subject: Re: [Elecraft] K3 - SWR Indication - Original Message - From: Steve Ellington n...@carolina.rr.com It appears that your coax does not exactly match the impedance of your dipole (It rarely does) - Thank you Steve for your comments. I fully accept about a probable mismatch between dipole and coax (and of course the performance of the antenna remains to be seen), also that there are many factors affecting SWR and that sampling at different points along the coax will produce different results if there is reactance in the load. In this case the antenna feeder was connected to the LP100A about 2.5 inches down the line from the ANT 1 socket. To my mind that seems a short length to account for an SWR difference at 7 Mhz as big as 1.2:1 (K3) vs 2.0:1 (LP100A and MFJ 259B). We all need to know what sort of load the rig or the amplifier is looking into and a discrepancy like that is unsettling. All three measuring devices see no reactance and 1.0:1 at 7.145 MHz. What seems to happen is that as one moves up or down in frequency from that point (and the load gains reactance) the K3 indication remains significantly lower than than other two. I doubt if 2.5 inches of coax would account for the difference and the MFJ259B, which agrees with the LP100A, connects to the antenna feeder at exactly the same point as the K3's ANT 1 socket so there is not even that extra 2.5 inches. It leads me to think that maybe my K3 is not measuring SWR as well as it should either due to a fault in my particular one or to the way it is set up to work. 73 to all Geoff G3UCK __ 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] K3 on-channel strong signal overload?
I have had some similar observations on ten meters. After reading your report I am inclined to agree with you. I have a station about 5 miles away who I contact on a regular basis on 10 meters, both SSB and CW. He is usually very distorted here and I have not been able to understand because others on the net do not seem to observe the distortion. I have also heard a few stations with strong skip that seem the same way. I have not tried a different antenna, but turning off the pre-amp helps some and engaging the attenuator helps even more. It makes sense to me that the front end overload clipping is activating and distorting the signal. It may not be such a problem now that I think I understand what is going on. Willis 'Cookie' Cooke K5EWJ --- On Sun, 5/3/09, orbarrett hoosa...@hotmail.com wrote: From: orbarrett hoosa...@hotmail.com Subject: [Elecraft] K3 on-channel strong signal overload? To: elecraft@mailman.qth.net Date: Sunday, May 3, 2009, 9:39 PM Hello all, I just finished operating my K3 from my friend's driveway using a portable dipole on 60M, and wanted to inquire about some incoming signal overload that cropped up. I was joined while ragchewing with some friends on 5371.5 __ 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] K3 on-channel strong signal overload?
I wonder if this could be caused by the TR switching diodes? Steve Ellington n...@carolina.rr.com - Original Message - From: WILLIS COOKE wrco...@flash.net To: orbarrett hoosa...@hotmail.com; Elecraft Reflector elecraft@mailman.qth.net Sent: Monday, May 04, 2009 11:51 AM Subject: Re: [Elecraft] K3 on-channel strong signal overload? I have had some similar observations on ten meters. After reading your report I am inclined to agree with you. I have a station about 5 miles away who I contact on a regular basis on 10 meters, both SSB and CW. He is usually very distorted here and I have not been able to understand because others on the net do not seem to observe the distortion. I have also heard a few stations with strong skip that seem the same way. I have not tried a different antenna, but turning off the pre-amp helps some and engaging the attenuator helps even more. It makes sense to me that the front end overload clipping is activating and distorting the signal. It may not be such a problem now that I think I understand what is going on. Willis 'Cookie' Cooke K5EWJ --- On Sun, 5/3/09, orbarrett hoosa...@hotmail.com wrote: From: orbarrett hoosa...@hotmail.com Subject: [Elecraft] K3 on-channel strong signal overload? To: elecraft@mailman.qth.net Date: Sunday, May 3, 2009, 9:39 PM Hello all, I just finished operating my K3 from my friend's driveway using a portable dipole on 60M, and wanted to inquire about some incoming signal overload that cropped up. I was joined while ragchewing with some friends on 5371.5 __ 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] K3 on-channel strong signal overload?
I don't think front end overload is your problem. I've had S9 + 45db signals sound perfectly fine on my K3 with no audio distortion and no off-frequency artifacts at all. I use the least amount of AGC possible ... AGC THR = 008 and AGC SLP = 000. The only way I've ever experienced audio distortion is when I turn the AGC off. On the other hand, K6LL and others have pointed out that the AF limiter in the K3 kicks in a bit early even if it is set to the maximum of 30. It's a pretty abrupt limiting action that can cause audio distortion, and if you have yours set lower than 30 you'd probably hear problems with even weaker signals. Also, are you using a speaker, either an external one or the one in the K3? You could be getting mechanical resonances on strong signals if you are. 73, Dave AB7E WILLIS COOKE wrote: I have had some similar observations on ten meters. After reading your report I am inclined to agree with you. I have a station about 5 miles away who I contact on a regular basis on 10 meters, both SSB and CW. He is usually very distorted here and I have not been able to understand because others on the net do not seem to observe the distortion. I have also heard a few stations with strong skip that seem the same way. I have not tried a different antenna, but turning off the pre-amp helps some and engaging the attenuator helps even more. It makes sense to me that the front end overload clipping is activating and distorting the signal. It may not be such a problem now that I think I understand what is going on. Willis 'Cookie' Cooke K5EWJ --- On Sun, 5/3/09, orbarrett hoosa...@hotmail.com wrote: From: orbarrett hoosa...@hotmail.com Subject: [Elecraft] K3 on-channel strong signal overload? To: elecraft@mailman.qth.net Date: Sunday, May 3, 2009, 9:39 PM Hello all, I just finished operating my K3 from my friend's driveway using a portable dipole on 60M, and wanted to inquire about some incoming signal overload that cropped up. I was joined while ragchewing with some friends on 5371.5 __ 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] K3 - SWR Indication
- Original Message - From: Steve Ellington n...@carolina.rr.com Geoff Try putting a 50 ohm dummy load in line and see if the K3 and your ext. meters read the same swr. This will take reactance and inbalance out of the picture. Thanks Steve. I did try that and with a 50 ohm dummy load all three meters show the same 1.0:1 SWR. It seems that the K3 meter responds differently from the other two to reactance in the load. 73 to all Geoff G3UCK __ 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] K3 on-channel strong signal overload?
On Sun, 3 May 2009 21:39:55 -0700 (PDT), orbarrett wrote: I was joined while ragchewing with some friends on 5371.5 by two other friends locally, one operating HF mobile from the same driveway and another operating from a base rig in the shack (using a backyard dipole antenna). When either of these two friends transmitted on the same channel (at 100W), I observed severe signal breakup in the K3 receive audio. Why are you surprised by this? This is entirely normal To investigate further, I switched the portable antenna from the K3 to my friend's FT-817 on the same operating table, and no audio breakup was observed under the same conditions. Returning the antenna to the K3, I then got rid of most of the signal breakup by turning on the input attenuator and turning down the RF gain to near minimum. DUH! Why are you surprised by this? You had the K3 set for maximum sensitivity and then hit it with a 100 watt transmitter. OF COURSE it's going to overload! You probably had the preamp on too, which is entirely un- necessary on 60M. The 817 is probably a much less sensitive radio, and may have a more brute force AGC. The K3 will outperform it by 40-50 dB in rejecting signals outside its passband. The K3 is doing exactly what you SET its controls to do -- pull very weak signals out of the mud. NO radio has infinite dynamic range. If you set it to perform well on weak signals (preamp on, attenuator off, RF gain all the way up), it's going to be badly overloaded by 100 watts ON FREQUENCY from an antenna 30 feet away. These are fundamental concepts of radio. It's too bad that they are seldom taught today. Most of us old farts learned them as Novices when we put our first rigs on the air. In those days, there were no transceivers. You had a transmitter and you had a receiver, and when you transmitted your receiver overloaded. 73, Jim Brown K9YC __ 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] K3 Output
I have never noticed slow variations in output during normal operations on my K3. However, the other day I installed the external ALC mod. During the testing step I connected and disconnected a 9 V battery with a series resistor. It took a couple of seconds for the K3 output to change. Seems like another reason not to actually hook it up to the amplifier. 73, Erik K7TV - Original Message - From: Ric Porter r...@comporium.net To: Elecraft@mailman.qth.net Sent: Monday, May 04, 2009 4:58 AM Subject: [Elecraft] K3 Output After 5 months use my K3 has developed an output problem. The output varies on tune or key down. If it is set on 100 watts, say on 20 meters, the out put will start at 65 watts. It then goes up to 110 and settles at 100 watts. All this is in a span of about two seconds. It does the same at five watts, or any power. It does the same on any antenna. It is ok at 1 mil through the two meter transverter. There is no device between the K3 and the different antennas. The variation is greater at the higher frequencies but does occur on all bands. Ric AA4SC __ 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] K3 on-channel strong signal overload?
G'day, I have a neighbour, VP8LP only 300 metres away. If I drop onto his frequency when he transmits the S-meter doesn't have enough digits to display. Only when my beam is pointing at him do I notice anything untoward on the audio. This goes away as soon as I switch on the attenuator or rotate the beam. We can usually work the same band, me on CW, Bob on SSB, both QRO. I'm inclined to go with K9YC. Regards, Mike VP8NO (old fart) __ 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] K3 on-channel strong signal overload?
This Duhing is entirely unfair. Didn't you read what he said? The author stated that he had the pre-amp off, RF gain at minimum, NB off, NR off and ATTN turned on. What more could he do to eliminate the overload? Without looking, I believe the MDS of the K3 and the FT-817 are probably similar on 60 meters. I believe he did everything possible with his settings. I still believe the problem could be the switching diodes producing IMD from that super strong signal and there may not be an easy cure. Steve Ellington n...@carolina.rr.com - Original Message - From: Jim Brown j...@audiosystemsgroup.com To: elecraft@mailman.qth.net Sent: Monday, May 04, 2009 1:01 PM Subject: Re: [Elecraft] K3 on-channel strong signal overload? On Sun, 3 May 2009 21:39:55 -0700 (PDT), orbarrett wrote: I was joined while ragchewing with some friends on 5371.5 by two other friends locally, one operating HF mobile from the same driveway and another operating from a base rig in the shack (using a backyard dipole antenna). When either of these two friends transmitted on the same channel (at 100W), I observed severe signal breakup in the K3 receive audio. Why are you surprised by this? This is entirely normal To investigate further, I switched the portable antenna from the K3 to my friend's FT-817 on the same operating table, and no audio breakup was observed under the same conditions. Returning the antenna to the K3, I then got rid of most of the signal breakup by turning on the input attenuator and turning down the RF gain to near minimum. DUH! Why are you surprised by this? You had the K3 set for maximum sensitivity and then hit it with a 100 watt transmitter. OF COURSE it's going to overload! You probably had the preamp on too, which is entirely un- necessary on 60M. The 817 is probably a much less sensitive radio, and may have a more brute force AGC. The K3 will outperform it by 40-50 dB in rejecting signals outside its passband. The K3 is doing exactly what you SET its controls to do -- pull very weak signals out of the mud. NO radio has infinite dynamic range. If you set it to perform well on weak signals (preamp on, attenuator off, RF gain all the way up), it's going to be badly overloaded by 100 watts ON FREQUENCY from an antenna 30 feet away. These are fundamental concepts of radio. It's too bad that they are seldom taught today. Most of us old farts learned them as Novices when we put our first rigs on the air. In those days, there were no transceivers. You had a transmitter and you had a receiver, and when you transmitted your receiver overloaded. 73, Jim Brown K9YC __ 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] K3 on-channel strong signal overload?
On Mon, 4 May 2009 13:36:18 -0400, Randy Downs wrote: I see distortion with a 40 over signal. 35 to 40 over seems to be when I see it. Preamp on. So turn the preamp off! Preamps are for weak signals on the higher HF bands. Preamps should NEVER be used below 20 meters, and rarely on 20M. Steve said: This Duhing is entirely unfair. Didn't you read what he said? Yes, and he said he got rid of most of the overload by minimizing the gain of the K3. The receiver in the K3 is a thoroughbred, souped up to copy weak signals with other strong signals AROUND them. It uses a lot of IF selectivity to do that. 100W ON FREQUENCY in the same driveway is an extreme case -- the IF filtering can't do anything at all. I suggest that you compute the voltage at the antenna terminals of the radio for the scenario described in the post. It is unreasonable to expect a souped up and well protected receiver to be completely free of overload under this condition. Have you ever worked a ham through a VHF repeater when you're less than a city block apart? It is VERY common for the other ham's transmitter to desense your receiver so that you can't hear the repeater! What's happening is that the other guy's transmitter is biasing your front end into cutoff (even with 600 kHz spacing on VHF, 5 MHz spacing on UHF). The K3 doesn't do that -- it keeps on working. But there is protection circuitry in the front end that prevents a big signal from frying something. Remember -- the K3 is not ONLY a QRP rig. Many hams use K3s in big contesting stations with legal limit amplifiers and SO2R -- that is, listening on one frequency while transmitting on another with a second radio. Those field strengths can fry the front end of a receiver that isn't well protected. The K3 IS protected. The small distortion he's hearing is part of the cost of that protection. 73, Jim Brown K9YC __ 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] K3 - SWR Indication
Hello Geoff, Which bands were you making the comparison on? Bob, N6CM On Mon, May 4, 2009 at 9:48 AM, Geoffrey Downs geoff...@downs.globalnet.co.uk wrote: - Original Message - From: Steve Ellington n...@carolina.rr.com Geoff Try putting a 50 ohm dummy load in line and see if the K3 and your ext. meters read the same swr. This will take reactance and inbalance out of the picture. Thanks Steve. I did try that and with a 50 ohm dummy load all three meters show the same 1.0:1 SWR. It seems that the K3 meter responds differently from the other two to reactance in the load. 73 to all Geoff G3UCK __ 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] K3 on-channel strong signal overload?
Hi, Just been looking through my archives. I remembered that there was a simple mod to the K2 to overcome audio distortion in an extreme overload environment, I installed it on my K2 and it was totally immune to co-channel audio distortion when my very near neighbour VP8LP transmitted: K2 - Improved Handling of Extremely strong (and nearby) Signals. Maybe the K3 architecture offers similar opportunities. Regards, Mike VP8NO __ 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] K3 on-channel strong signal overload?
On Mon, 4 May 2009 14:12:09 -0400, Randy Downs wrote: It's on 10 meters. Should I not run 10 meters? Of course not. Just don't be surprised when several volts of on- frequency RF causes overload. 73, Jim K9YC __ 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] K3 on-channel strong signal overload?
Mike, That mod to the K2 (which has been incorporated into the new K2s) is simply a limiter. If the signal level at the input to the IF amplifier ever increases to the point where the diodes clip the signal, then distortion will occur. The clippping distortion may not be noticed on CW, but it certainly will distort SSB and data signals. There is a mod for the K3 to change to a larger choke in the AF amplifier. If that change is not installed, distortion can occur in the AF amp itself. But all in all, Jim Brown is correct - a large signal like what was reported is certain to cause activation of the COR at the K3 input (input protection) and distortion is to be expected in situations like that. It is also likely that the K3 Hardware AGC is maxed out and can lower the gain no more with the resulting of overload of the ADC. Without making measurements, it is difficult to say just where the overload point(s) might have been, but it is clear that a 100 watt signal ON FREQUENCY with antennas close to each other is certain to create overload and the distortion is a natural 'happening' under such overload conditions -- in other words, the K3 dynamic range (as good as it is) was exceeded - everything has its limits. 73, Don W3FPR Mike Harris wrote: Hi, Just been looking through my archives. I remembered that there was a simple mod to the K2 to overcome audio distortion in an extreme overload environment, I installed it on my K2 and it was totally immune to co-channel audio distortion when my very near neighbour VP8LP transmitted: K2 - Improved Handling of Extremely strong (and nearby) Signals. Maybe the K3 architecture offers similar opportunities. Regards, Mike VP8NO __ 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] K3 on-channel strong signal overload?
Why are we throwing stones? The K-3 is different than other transceivers that we have used. In the heat of a contest or chasing DX one does not always immediately make sense of what is happening. Sharing some observations about characteristics of Elecraft products along with ways of dealing with a peculiarity is one of the great benefits of this forum. It took several episodes and a post from a fellow K-3 owner for the light to dawn on me. I never saw this problem with my BC-455, my S-53, my Hammarlund Super-Pro. Turning off the preamp and kicking on the attenuator work very well, but one has to think about it. Now that we have thoroughly discussed the subject we will probably all remember to do it. Unfortunately many of us will be reluctant to admit to having confusion and offer our experience and solution for fear of someone calling us stupid. I will not have that problem because I really don't care if someone calls me stupid. Willis 'Cookie' Cooke K5EWJ __ 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] K3 on-channel strong signal overload?
I haven't ever experienced a problem with strong on-channel overload with the K3. But it's possible that you're hitting it with so much power that you're putting one or more RX stages into saturation, possibly including the I.F. amp. (In an extreme case, you could even be exceeding the useful range of the TR switch PIN diodes. The FT817, if I'm not mistaken, uses a TR relay.) While it's perfectly reasonable to expect the operator to turn on the attenuator in such a situation, there may be a way to modify the K3 to handle these signals, depending on where the saturation is occurring. As an experiment, I would try adding back-to-back silicon diodes (1N4148 or 1N914) at the output of the crystal filter and/or at the output of the IF amp. The question is where to add them. One possibility is across the primary of T5 in the IF amp, which would drastically limit the max p-p voltage obtainable from this stage. Another, less-invasive possibility would be across L39. At any normal signal level the diodes would be essentially out of the circuit. On large signals, they'd clamp the voltage at this point to about 1.4 Vpp. 73, Wayne N6KR --- http://www.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
[Elecraft] shift/width - hi/lo cut
Is there a way to vary the rate of change which seems to be set at 10Hz? I'd like it to be 5Hz for PSK. Some of the stations are too close together to sort them out. Having said that - I'm by no means an expert at PSK Tom GM4FDM __ 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] K3 on-channel strong signal overload?
(In an extreme case, you could even be exceeding the useful range of the TR switch PIN diodes. The FT817, if I'm not mistaken, uses a TR relay.) Some scratch-paper calculations in a 50-ohm system: Assuming it really is the T/R PIN diodes, they would conduct at just under one volt. In a 50-ohm system (and highly dependent on the PIN configuration), that's roughly a 10 dBm signal -- or stated another way, 10 mW of power dissipated at the Rx front end. It would be an interesting exercise to momentarily bypass the T/R PIN diodes and re-test with the same driveway setup. So, even if this really is the cause, it would probably be a safe assumption that the K3 will still handle strong signals far better than most other receivers -- until an outrageously high value begins conducting PIN diodes. That solution might call for replacement of the solid-state T/R with a relay. Thanks, but no thanks. Paul, W9AC __ 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] My Attitude
Crew, Some feel that my posts are sometimes harshly worded. Perhaps they are. But it seems to me that someone with a General Class ham license, and especilly someone with an Extra Class ticket, ought to have spent some time studying something more than the Study Guide to pass the exam. This is ham radio, not CB radio. A ham license is not a boxtop license. As hams, we are granted rather extensive operating privileges on the basis of our technical knowledge, our advancement of the state of the art, and our preparedness for emergencies. As hams, it is our responsibility to STUDY this stuff. The ARRL Handbook is very well written, and includes chapters that cover all of this material in a manner that is quite readable. You don't have to have a lot of math or physics or engineering background to understand it. All you have to do is make a serious effort. I admit to being a grandfatherly curmudgeon. And I'm probably going to stay that way until they throw dirt on me. 73, Jim Brown K9YC __ 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] K3 on-channel strong signal overload?
Hi Don, Quote The two diodes limit the signal to 1.4 V peak-to-peak. Even when the diodes are conducting, i.e. when the signal is so strong that it looks like a square wave at pin 4, there is no audible signal distortion. This is because the MC1350 is followed by a second crystal filter which removes any harmonic distortion products (i.e. multiples of 4.915 MHz). The diodes appear to have no other side-effects. Unquote. Indeed, no distortion noted CW or SSB. Regards, Mike VP8NO - Original Message - From: Don Wilhelm w3...@embarqmail.com To: Mike Harris mike.har...@horizon.co.fk Cc: Reflector Elecraft Elecraft@mailman.qth.net Sent: Monday, May 04, 2009 2:47 PM Subject: Re: [Elecraft] K3 on-channel strong signal overload? | Mike, | | That mod to the K2 (which has been incorporated into the new K2s) is | simply a limiter. | If the signal level at the input to the IF amplifier ever increases to | the point where the diodes clip the signal, then distortion will occur. | The clippping distortion may not be noticed on CW, but it certainly will | distort SSB and data signals. __ 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] K3 on-channel strong signal overload?
40 over is several volts? I thought it was around 5 mili volts. That's what I am talking about. I've seen this distortion in signals since several fw revisions ago. If I get time tonight I'll reload some earlier rev's. Randy K8RDD - Original Message - From: Jim Brown j...@audiosystemsgroup.com To: Elecraft List elecraft@mailman.qth.net Sent: Monday, May 04, 2009 2:34 PM Subject: Re: [Elecraft] K3 on-channel strong signal overload? On Mon, 4 May 2009 14:12:09 -0400, Randy Downs wrote: It's on 10 meters. Should I not run 10 meters? Of course not. Just don't be surprised when several volts of on- frequency RF causes overload. 73, Jim K9YC __ 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] My Attitude
Or maybe you don't listen very well. I said nothing about a several volt signal. I'm talking about 40 over s9. Maybe I should have explained it better to the group. No the nb is not on as this will cause distortion depending upon the blanking level. (IF) blanking. I expected that some would trust that others actually know as much or more than some and know better than making the mistake of feeding a several volt signal or having the blanker on at a high level and not seeing distortion. Or maybe we can be helpful and not flame. This is not cb so maybe we should be less critical of others. Cb'ers would flame. And you have no idea that I'm an EE for General Electric. I'll forgive you. Maybe we can just relax and act like ham's not Cb'ers.. ;) Randy K8RDD - Original Message - From: Jim Brown j...@audiosystemsgroup.com To: Elecraft List elecraft@mailman.qth.net Sent: Monday, May 04, 2009 4:23 PM Subject: [Elecraft] My Attitude Crew, Some feel that my posts are sometimes harshly worded. Perhaps they are. But it seems to me that someone with a General Class ham license, and especilly someone with an Extra Class ticket, ought to have spent some time studying something more than the Study Guide to pass the exam. This is ham radio, not CB radio. A ham license is not a boxtop license. As hams, we are granted rather extensive operating privileges on the basis of our technical knowledge, our advancement of the state of the art, and our preparedness for emergencies. As hams, it is our responsibility to STUDY this stuff. The ARRL Handbook is very well written, and includes chapters that cover all of this material in a manner that is quite readable. You don't have to have a lot of math or physics or engineering background to understand it. All you have to do is make a serious effort. I admit to being a grandfatherly curmudgeon. And I'm probably going to stay that way until they throw dirt on me. 73, Jim Brown K9YC __ 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] [K2] NB question re: pulse noise problem here
On the 40M band only I'm getting an S7 pulse noise during much of the day making 40M nearly unusable. Most nights I don't hear it but last night it was just as bad as during the day. The pulse's are approx. 30hz and short in duration. My antenna is a vertical (my only option here). I would like to know if you think the K2 Noise Blanker option might block these pulses. I'm doubtful but if anyone thinks it might I'll get it asap. Other than this pulse noise I don't have any unusual noise noise issues. Ron N7IB __ 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] [K2] NB question re: pulse noise problem here
Ron It's a very inexpensive option. I'd try it. I have it in both my K2s and it works just fine on some noises and not on others. Even the K3 has this problem though. Good luck and 73 Bob N6WG - Original Message - From: Ron Greene rgte...@roadrunner.com To: elecraft@mailman.qth.net Sent: Monday, May 04, 2009 2:01 PM Subject: [Elecraft] [K2] NB question re: pulse noise problem here On the 40M band only I'm getting an S7 pulse noise during much of the day making 40M nearly unusable. Most nights I don't hear it but last night it was just as bad as during the day. The pulse's are approx. 30hz and short in duration. My antenna is a vertical (my only option here). I would like to know if you think the K2 Noise Blanker option might block these pulses. I'm doubtful but if anyone thinks it might I'll get it asap. Other than this pulse noise I don't have any unusual noise noise issues. Ron N7IB __ 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] K3 on-channel strong signal overload?
Good day: I can't help myself. :-) The usual definition of an S9 signal is 50 uVolts, or -73 dBm (assuming a 50 Ohm load). The S-Meter unit is a 6 dB change in VOLTAGE, not power. To get one VOLT, we need 2000 times 50 uVolts, or S9 + about 86dB (86 dB over S9). 40 over is about 5 mVolts... The formula for the dB difference for two voltages, assuming you want a power and have the same load, is 20 * log (V2/V1). If you want dB's over S9, let V1 be 50 uV, (50E-6 Volts). Now, let's hope I managed to get this right. :-) 73, Mark - Original Message - From: Randy Downs randyddo...@gmail.com To: elecraft@mailman.qth.net, Jim Brown j...@audiosystemsgroup.com Sent: Monday, May 4, 2009 4:37:01 PM GMT -05:00 US/Canada Eastern Subject: Re: [Elecraft] K3 on-channel strong signal overload? 40 over is several volts? I thought it was around 5 mili volts. That's what I am talking about. I've seen this distortion in signals since several fw revisions ago. If I get time tonight I'll reload some earlier rev's. Randy K8RDD - Original Message - From: Jim Brown j...@audiosystemsgroup.com To: Elecraft List elecraft@mailman.qth.net Sent: Monday, May 04, 2009 2:34 PM Subject: Re: [Elecraft] K3 on-channel strong signal overload? On Mon, 4 May 2009 14:12:09 -0400, Randy Downs wrote: It's on 10 meters. Should I not run 10 meters? Of course not. Just don't be surprised when several volts of on- frequency RF causes overload. 73, Jim K9YC __ 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
Re: [Elecraft] My Attitude
On Mon, 4 May 2009 16:55:02 -0400, Randy Downs wrote: Or maybe you don't listen very well. Possible. But I sure thought I read that the overload was occuring on another mobile parked in the same driveway and the signal from a dipole used by another station in whose driveway they were parked. Do the math on that and you can get several volts, depending on antenna types, directivity, and proximity. S-meters are notoriously inaccurate, especially at their upper and lower limits, even on a K3. 73, Jim K9YC __ 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] ECN Report: The Rest of the Story
Good Afternoon, I now have the previously unlisted QNIs. I will fill in the slots as I go. Added entries have been indented for your convenience. On to the list = On 14050 kHz at 2300z: NO8V - John - MI - K3 - 820QNI #65!!! K4JPN - Steve - GA - K2 - 1422 AB9V - Mike - IN - K3 - 398 N0SS - Tom - MO - K3 - 008 K9ZTV - Kent - MO - K3 - 21 K4JPN - Steve - GA - K2 - 1422 K6PJV - Dale - CA - K3 - 1183 K1THP - Dave - CT - K3 - 686 QNI #80!!! WB5BKL - Nick - TX - K3 - 231 K6DGW - Fred - CA - K3 - 642 N0TA - John - CO - K3 - 994 N7KRT - Jeff - TX - K2 - 5471 W6JDB - Jay - OR - K3 - 1288 K2HYD/7 - Ray - 7? - KX1 - 608 K1EV - Bill - CT - K2 - 2152 N6JW - John - CA - K3 - 936 N3ND - Dan - FL - K3 - 1567 KB3FBR - Joe - PA Now that I have all the data I find we gained a respectable total of 34 check ins. Thank you! From the email I am receiving this could have been larger but the pileup Tom generated was hard to break ;) Too bad I could not have continued his run when he passed control back to me. Oh well, there is always next week. Until next Sunday stay dry, Kevin. KD5ONS (NCO5C) - __ 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] K3 on-channel strong signal overload?
On Mon, 4 May 2009 21:10:46 + (UTC), k...@comcast.net wrote: Now, let's hope I managed to get this right. :-) Nothing wrong with your math. The likely error is in assuming that ANY S-meter is accurate at the extremes of its range. All the S- meters I've seen compress both at the top and bottom of their range. As others have noted, the protection diodes will conduct to limit the input that the receiver sees to about a volt, even though those diodes may be seeing more. When those diodes conduct they will produce some distortion. That's the nature of diodes. Note also that the circuits driving the S-meter in the K3 can be set to correct for the gain added by the preamp and subtracted by the attenuator, or not. And, of course, you've got to calibrate the S- meter with a voltage source of known accuracy. 73, Jim K9YC __ 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] K3 on-channel strong signal overload?
--- On Mon, 5/4/09, k...@comcast.net k...@comcast.net wrote: From: k...@comcast.net k...@comcast.net Subject: Re: [Elecraft] K3 on-channel strong signal overload? To: elecraft@mailman.qth.net Date: Monday, May 4, 2009, 3:10 PM Good day: I can't help myself. :-) The usual definition of an S9 signal is 50 uVolts, or -73 dBm (assuming a 50 Ohm load). The S-Meter unit is a 6 dB change in VOLTAGE, not power. To get one VOLT, we need 2000 times 50 uVolts, or S9 + about 86dB (86 dB over S9). 40 over is about 5 mVolts... The formula for the dB difference for two voltages, assuming you want a power and have the same load, is 20 * log (V2/V1). If you want dB's over S9, let V1 be 50 uV, (50E-6 Volts). Now, let's hope I managed to get this right. :-) You got the right answer (86 dB) but when using your slide rule you didn't keep track of the decimal point. One volt is 20,000 * 50 uV. Wes Stewart, 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
Re: [Elecraft] K3 Output
I also have found that the K3 ALC response time appears too slow to be useful. Maybe it can be fixed in Firmware. I going to disable it until it is fixed. 73 Ken K5DNL --- On Mon, 5/4/09, Erik N Basilier ebasil...@cox.net wrote: From: Erik N Basilier ebasil...@cox.net Subject: Re: [Elecraft] K3 Output To: Ric Porter r...@comporium.net, Elecraft@mailman.qth.net Date: Monday, May 4, 2009, 12:18 PM I have never noticed slow variations in output during normal operations on my K3. However, the other day I installed the external ALC mod. During the testing step I connected and disconnected a 9 V battery with a series resistor. It took a couple of seconds for the K3 output to change. Seems like another reason not to actually hook it up to the amplifier. 73, Erik K7TV - Original Message - From: Ric Porter r...@comporium.net To: Elecraft@mailman.qth.net Sent: Monday, May 04, 2009 4:58 AM Subject: [Elecraft] K3 Output After 5 months use my K3 has developed an output problem. The output varies on tune or key down. If it is set on 100 watts, say on 20 meters, the out put will start at 65 watts. It then goes up to 110 and settles at 100 watts. All this is in a span of about two seconds. It does the same at five watts, or any power. It does the same on any antenna. It is ok at 1 mil through the two meter transverter. There is no device between the K3 and the different antennas. The variation is greater at the higher frequencies but does occur on all bands. Ric AA4SC __ 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
[Elecraft] One more main body posting test
I hope this will be the last test of my e-mail problem. Thanks for bearing with me on this. 73 Dan af4lb __ 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] K3 on-channel strong signal overload?
Jim, I have some questions. DUH! Why are you surprised by this? You had the K3 set for maximum sensitivity and then hit it with a 100 watt transmitter. OF COURSE it's going to overload! I don't think this is follows naturally. Doesn't the automatic gain control (AGC) do the same thing as the RF gain control? As Oliver pointed out, he didn't have the preamp on. It seems to me Oliver is describing a failure of the AGC to properly engage the HAGC , staying only in the DSP gain control area. I've asked Oliver to report the firmware version, as I believe there have been updates in the firmware since the official release that are in the beta releases only. These are fundamental concepts of radio. It's too bad that they are seldom taught today. Most of us old farts learned them as Novices when we put our first rigs on the air. In those days, there were no transceivers. You had a transmitter and you had a receiver, and when you transmitted your receiver overloaded. A few minutes of search would have shown that Oliver is the person who originally reported this problem with the K2 in 2003, which resulted in the back-to-back diode clamp. You may be right that Elecraft doesn't design for strong in-passband signals, but it's not clear that that's an fundamental limitation of RF technology, especially since the RF gain control can handle it manually. It doesn't seem to me an unreasonable request that the firmware be able to detect this same situation and properly handle the gain stages (hardware and DSP) at least as well as manual RF gain control. You might want to re-read this message: http://www.qsl.net/ve3mcf/elecraft_reflect/K2_Howling_Fix.txt Leigh/WA5ZNU __ 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] K3 - SWR Indication
Geoff, That test at 50 ohms substantiates that the wattmeters are properly balanced for a 50 ohm system, and nothing more - read on if you are interested in more skepticism. Contrary to several statements made, it is quite possible that *all* those wattmeters can be wrong when reporting SWR that is greater than SWR = 1.0. Although I have faith in Larry's calibration of forward power for the LP100 meter, I don't have much information about what he does for the reverse power calibration, so I cannot comment with any degree of certainty - I can only speculate that some error is possible. Likewise, I do not have the details of the alignment procedures for the K3 reverse power calibration, so I can be just as skeptical of the K3 SWR indication as I am of the LP-100. Before I stick my head further onto the chopping block, I can say that the forward power indication for both the K3 and LP-100 is quite good if properly calibrated (and most are - so they should have reasonable agreement). Most any wattmeter is balanced to produce zero reflected voltage when terminated in its design impedance (normally 50 ohms resistive). But when the load is different than 50 ohms, there will be some reflected voltage indicated. The gain of the amplifiers following the detector must be set to indicate the proper SWR, just like the gain of the forward voltage must be calibrated to indicate the correct forward power. To do that SWR calibration properly requires one or more loads of known impedance. When I calibrate a wattmeter (in the KXAT1, KAT1, KAT2, KPA100 or KAT100), I use a precision 25 ohm and 100 ohm pure resistive dummy load (connected with the shortest possible connection) to set the SWR = 2.0 point. The resistors I use for these dummy loads are Caddock thick film 50 ohm 1% resistors (connected in parallel for 25 ohms and connected in series for 100 ohms). These resistors are known to be pure resistances up to 500 MHz, so I know I can trust them (and they have been measured on a VNA). So bottom line, I cannot vouch for the accuracy of any wattmeter's SWR indication until I can test them with my precision loads (Trust no tool until it has proven its worth). I do not believe the K3 SWR indication is intended to be a precision measurement tool, it's major purpose is to find the lowest SWR while the KAT3 is tuning, and it will do that task quite well without precise calibration. Larry will have to speak for the LP-100 SWR accuracy. Actually, there is more to forward power and reverse power calculation that must be handled in an instrument that will correctly indicate both (and 2 different instruments may do it differently). The actual power must take the voltage developed by the forward detector and subtract the reflected power to obtain the actual forward power. The voltage developed by the reverse detector must also be subjected to calculations to determine the actual SWR (which also has a relationship to the forward power). The one meter that I am familiar with which takes all this into consideration is the KI6WX Tandem Match. The Tandem Match does the calculations necessary by using operational amplifiers to do the required summing, subtraction, and conversion to logarithms so we can view the actual forward power and SWR. That task can also be done with a pic (firmware), but even so, it still requires some calibration steps to get everything right and calibrated. and not all wattmeters go to the trouble of doing all the necessary math - some can simply report the reflected power directly on some SWR scale - which will only accurately report the SWR when it is 1.0:1. So, my bottom line advice is that most any wattmeter designed for a 50 ohm system can be trusted when it indicates SWR = 1.0 with a 50 ohm load, but beyond that point, it is difficult to say how accurate it really is until it is proven to have accuracy within reason for SWR indications. OK, my skepticism about wattmeters is showing once again - only this time with SWR rather than my usual tirades about the inaccuracies of the forward power indications of wattmeters (+/- 20% of full scale specs). 73, Don W3FPR Geoffrey Downs wrote: - Original Message - From: Steve Ellington n...@carolina.rr.com Geoff Try putting a 50 ohm dummy load in line and see if the K3 and your ext. meters read the same swr. This will take reactance and inbalance out of the picture. Thanks Steve. I did try that and with a 50 ohm dummy load all three meters show the same 1.0:1 SWR. It seems that the K3 meter responds differently from the other two to reactance in the load. 73 to all Geoff G3UCK __ 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
