Re: [Elecraft] Question re TXMON
The waveform display in the P3 TX monitor auto-ranges to keep the modulation peaks within the display limits. However, if the forward power gets high enough to over-range the ADC, then the waveform will be clipped. With the 200W HF sensor, I believe the clipping level is about 240-250 watts, depending on the calibration. With 100W out of the K3 and assuming 100% efficiency in the tuner, the SWR would have to get up to about 7.7:1 to cause clipping of the displayed waveform. Alan N1AL On 06/07/2016 01:23 PM, Bob Novas wrote: I wondered if a high SWR affects the waveform that the P3 displays - wouldn't the voltages be higher at high SWR? would that put the txmonitor into a non -linear region? -Original Message- From: Elecraft [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Alan Bloom Sent: Tuesday, June 07, 2016 3:29 PM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] Question re TXMON There is no reason to disconnect the P3 from the sensor. The sensor can't damage the P3. I suppose there might be a danger of damaging the sensor if you are running high power into a very high SWR, but if it is in a range that the K3 ATU can tune, I can't imagine there would be a problem. Alan N1AL On 06/07/2016 10:37 AM, Steve via Elecraft wrote: I have recently added P3 to my K3 and (surprise!) I love it. My (previously owned) P3 came with TXMON. TXMON works fine with dummy load, but often shows very high SWR readings when K3 ATU is used with non- resonant antenna. I understand that the TXMON "looks at" antenna and doesn't know what ATU is doing. My question is, "Is there any problem or danger to leave the TXMON connected when using ATU on non-resonant part of antenna bandwidth? My reason to ask is that tab to release TXMON sensor plug is right up against top RS232 plug and I need to disconnect that plug in order to disconnect TXMON sensor cable. TNX ES 73 de W3UEC (Steve) __ 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 bob.no...@verizon.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] Question re TXMON
I wondered if a high SWR affects the waveform that the P3 displays - wouldn't the voltages be higher at high SWR? would that put the txmonitor into a non -linear region? > -Original Message- > From: Elecraft [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Alan > Bloom > Sent: Tuesday, June 07, 2016 3:29 PM > To: elecraft@mailman.qth.net > Subject: Re: [Elecraft] Question re TXMON > > There is no reason to disconnect the P3 from the sensor. The sensor can't > damage the P3. > > I suppose there might be a danger of damaging the sensor if you are running > high power into a very high SWR, but if it is in a range that the K3 ATU can tune, I > can't imagine there would be a problem. > > Alan N1AL > > > On 06/07/2016 10:37 AM, Steve via Elecraft wrote: > > I have recently added P3 to my K3 and (surprise!) I love it. My > > (previously owned) P3 came with TXMON. TXMON works fine with dummy > > load, but often shows very high SWR readings when K3 ATU is used with non- > resonant antenna. > > I understand that the TXMON "looks at" antenna and doesn't know what > > ATU is doing. My question is, "Is there any problem or danger to leave > > the TXMON connected when using ATU on non-resonant part of antenna > > bandwidth? My reason to ask is that tab to release TXMON sensor plug > > is right up against top > > RS232 plug and I need to disconnect that plug in order to disconnect > > TXMON sensor cable. > > > > TNX ES 73 de W3UEC (Steve) > > > __ > 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 bob.no...@verizon.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] Question re TXMON
There is no reason to disconnect the P3 from the sensor. The sensor can't damage the P3. I suppose there might be a danger of damaging the sensor if you are running high power into a very high SWR, but if it is in a range that the K3 ATU can tune, I can't imagine there would be a problem. Alan N1AL On 06/07/2016 10:37 AM, Steve via Elecraft wrote: I have recently added P3 to my K3 and (surprise!) I love it. My (previously owned) P3 came with TXMON. TXMON works fine with dummy load, but often shows very high SWR readings when K3 ATU is used with non-resonant antenna. I understand that the TXMON "looks at" antenna and doesn't know what ATU is doing. My question is, "Is there any problem or danger to leave the TXMON connected when using ATU on non-resonant part of antenna bandwidth? My reason to ask is that tab to release TXMON sensor plug is right up against top RS232 plug and I need to disconnect that plug in order to disconnect TXMON sensor cable. TNX ES 73 de W3UEC (Steve) __ 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] Question re TXMON
I have recently added P3 to my K3 and (surprise!) I love it. My (previously owned) P3 came with TXMON. TXMON works fine with dummy load, but often shows very high SWR readings when K3 ATU is used with non-resonant antenna. I understand that the TXMON "looks at" antenna and doesn't know what ATU is doing. My question is, "Is there any problem or danger to leave the TXMON connected when using ATU on non-resonant part of antenna bandwidth? My reason to ask is that tab to release TXMON sensor plug is right up against top RS232 plug and I need to disconnect that plug in order to disconnect TXMON sensor cable. TNX ES 73 de W3UEC (Steve) __ 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