[Elecraft] K4 Status Update
Hi Eric What distribution of embedded Linux is used in the K4, I am curious? 73CraigVK3OD __ 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] K4 S-meter characteristics
Will the K4 have alternate S-meter scales since its direct sampling. Dbm, and Dbuv would be useful. Will the K4 have better S-meter resolution or a menu option to set the dynamic range to give better indications of nulls or peaks? It would be nice to limit the range in 2 scales S1 to S9 and then the normal 60db above S-9. Will there be a feature to allow the s-meter data to be accessed in linear manner to do antenna polar plots? It would be a shame to squander the potential of the K4 especially if the S-meter is linear and accurate. I am sure the potential is endless being direct sampling architecture and its just a matter of priorities! I have used a Perseus for a number of years and as a accurate measuring instrument it is indeed superb. It would be nice if the K4 had this potential inherent in the design 73CraigVK3OD __ 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] IMD and supply voltage
Hi Wayne How about these ham transceivers? I pulled the data from my saved QST reviews of these radios that I have owned in the past. I do recall that they did have transmitter IMD data that was head and shoulders above what was available when they were released. This data is from the QST reviews and not my owned measured data. All these radios operated on a 12 volt supply. FT990 3rd -38 5th -47 FT767 3rd -40 5th -45 TS450 3rd -35 5th -49 IC737 3rd -39 5th -48 The higher order data from the QST reviews indicated a rapid fall off above the 5th to the 11th order. Low IMD figures while operating from a 12 volt power supply certainly seems to be realizable. 73 Craig "If you have another marine radio in mind that you think is using different/better circuitry, please let me know so we can repeat this exercise if necessary. 73, Wayne N6KR" __ 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] SS30DV feedback OT
Very impressive indeed. Pre-distortion will hopefully be made available as a option for the K3 in the future. That would be a superb option if it does become available. What these results however do confirm is that pre-distortrion is worth implimenting and that it does work very well. The work by N1JEZ also confirms that current LDMOS amplifiers do not have acceptable levels of IMD performance, especially at higher powers. In my opinion based on the IMD data by N1JEZ they are inherently very dirty. I have not seen a working example of a LDMOS amplifier that I would consider clean when compared against even a pair of 3-500's. I have studied the NXP datasheets for these devices and have found that LDMOS devices like the BLF574 can produce excellent IMD performance. The BLF574 according to the data sheet at 200 watts of ouput and 1200ma of idle current is capable of -40dbc 3rd order IMD performance. I have not seen data for the higher order products but this figure is good. I have been working on a homebrew LDMOS solid state amplifier for my K3 and have not decided what devices I will use in the design. I do have a MRF150/EB104 amplifier that works very well and it has very good IMD performance. I would like to try these LDMOS designs. I wont however waste effort on a marginally poor IMD PA. Homebrewing is a lot of effort and I cant see the point of spending dollars and time on any project when it does not meet acceptable technical standards like IMD performance.. I wonder when we will see pre-distortion in a commercial ham radio tranceiver outside of the experimental devlopments like HPSDR. Is Elecraft working on a pre-distortion implimentation? 73 Craig "With bias, 12V transistors are class B or AB, not C. See http://flarc.net/eme-info/PDF/N1JEZ-2.pdf. Ignacy, NO9E" __ 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] P3 Feature Request - Transmit sampling
If this feature is offered in the near future, it would be nice if the following features were incorporated into the making the P3 a very useful station tool. 1. Since the Dynamic range is rather limited on the P3, the ability or feature to allow 1 or 2 crystal notch filters to be inserted inline would be a nice feature. This would allow the dynamic range of the P3 to be increased to something well over 100db with the main TX signal notched. We would only a need a low frequency, mid and high frequency notches for dummy load testing. 2. The ability to define a IMD mask would be a nice feature. Rather than trying to squint at peak makers it would be much easier to set a fail alarm mask that alerts the operator to the fact that his or her's knobs to the right habit is causing problems up the band. 3. Multiple peak markers and a rifle scope type cross hair makers for making accurate and fast level measurements. Pre-set bounce peak level markers every 5 khz would be a nice feature. 4. Have multiple traces such as peak hold, quasi peak, average power, average power in a 2.4khz bandwidth, and peak power in a 2.4khz bandwidth These kinds of measurements would reflect the level of interference as seen on the typical S_meter rather than being a narrow resolution bandwidth measurement. 5. If you are doing transmitter sampling you might as well go all the way and offer the ability to use any directional coupler with the P3 with appropriate calibration routines. Similar to the http://www.meterbuilder.com/ meter. 6. Support software for the G4HFQ polar plotting software. http://www.g4hfq.co.uk/plphelp/plphelp.htm 7. While they at it a white noise generator plus a 2 tone or multitone generator can also be a option for TX testing. 8. Define a set bandwidth such as 20khz for TX monitoring that can be stored to one of the P3's function keys ALT would switch the waterfall display to the 20khz bandwidth and the averaging on the waterfall should indicate IMD level peaks averaged in a 2.4khz bandwidth. Its a complicated matter turning the P3 into a spectrum analyzer/station monitor once you start thinking about it from the perspective of a test engineer. It might be easier to do this on a DDC/DUC platform! That should round the P3 off very nicely if all these features are achievable. Only the firmware guru's will know if these features are possible. Keep on dreaming. 73 Craig __ 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] P3/SVGA Beta Firmware 1.24/1.14 Now Available
Hi Tom Thanks, I seem to have got lucky. I reloaded the old Beta and then tried loading the new Beta and it worked fine. All is good now, false alarm! Thanks Craig It worked fine for me. The first thing I noticed was what seemed to be faster response time for the noise and signal peaks, which is an improvement. __ 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] P3/SVGA Beta Firmware 1.24/1.14 Now Available
Hi Paul I have had all sorts of problems trying to update to this beta release. The upload crashed after the MCU load. I tried several times with no success. It seems that something gets corrupted after the reset process. The P3 does actually reset however the update to the P3 Utility seems rather slow. I even tried using the MCU bootloader with the same failure. I have tried about 6 times and it has failed on every attempt. I thought that it was the USB-serial driver that got corrupted. I tried a dedicated RS232 port on another PC with the same result. I also disconnected the K3 from the P3 with no success. I have successfully loaded the previous beta so I presume that their is no issue with my PC setup. This might be some issue with my P3, although its running fine after re- installing the previous beta. Is there something different in this beta release that makes loading problematic? Craig VK3OD __ 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 - background hiss
I use a Datong FL3 audio filter and the difference to my ears is amazing. The K3 sounds a lot lesser hissy and is very warm sounding when compared to the unfiltered radio. Yes, I have tried all AGC and EQ settings.The difference can not be equaled by just adjusting the RX EQ or by using a pink noise roll off mask. My Datong FL3 is hooked up permanently to the K3 and I can easily switch it in and out. Anecdotal comments from other hams also confirms the filters efficacy. I have the DSP board upgrade in the K3. I have perfect hearing, so its not my ears coloring the results. The K3's hiss does have a sharp bite to it that was fixed by using the Datong filter. I know what real hiss is, having owned a TS530S and a FT990 both of which had the worst imaginable IF hiss. When I tried these radio again I could not believe how quiet the K3 really is however you then use a SDR radio and your perspective of what quiet is changes! Maybe the K2 SCAF or some other SCAF will do the same job as the Datong. Datongs audio filter has a legendary reputation and its audio peak filter on CW and general filtering qualities leave many DSP radios for dead. Amazing for a 30 year old box! If you can find a Datong FL3 buy it! 73 Craig __ 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
