Re: [Elecraft] KBPF3 upgrade kit and instructions now available
However, if you are installing a KBPF3A in an existing K3 you will still want to add the bypass capacitors to the regulators on the main board and in the KRX3 if installed. 73, ... Joe, W4TV On 2015-06-25 12:34 AM, Wayne Burdick wrote: On Jun 24, 2015, at 9:23 PM, Michael Eberle mtebe...@mchsi.com wrote: Will new orders for the KBPF3 have the modification already done… Yes. That's the KBPF3A. 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 li...@subich.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] KBPF3 upgrade kit and instructions now available
Hi all, The long-promised KBPF3 modification kit is now available. It applies to the KBPF3, K3 RF board, and optionally to the KRX3 sub receiver. It allows the K3 or K3S to receive signals in the 100-500 kHz range with good sensitivity. This is an interesting part of the spectrum, with For full details on the mod kit, see: http://www.elecraft.com/order_form_parts.htm#K3%20Parts Also see below for an excerpt from my original posting about signals in the 100-500 kHz range. 73, Wayne N6KR * * * In honor of the FCC's proposed 2200 meter allocation (137 kHz), we decided to see if we could improve the K3's receive sensitivity in the 100-500 kHz range. This extended coverage is made possible by the new synth (KSYN3A). After a lot of digging, we discovered the cause of the wide-band low-frequency noise. We also found a way to shift the passband of the KBPF3 lower. With a couple of simple modifications, the MDS (minimum discernible signal) can be improved by about 25 dB at the low end (100 kHz). Here are some test results (preamp off, 400-Hz bandwidth): 137 kHz -114 dBm FCC's proposed 2200 meter band 160 kHz -117 dBm low end of the Low-Fer band 250 kHz -126 dBm test frequency in the long-wave beacon band 472 kHz -133 dBm 630 meter experimental band This represents an improvement throughout the range, but especially at the low end. I believe -114 dBm MDS should suffice at 137 kHz, given the high band noise in this range. Another indication of how well the mods work: With no antenna connoted, the K3's S-meter now just barely flickers (S1) at 100 kHz. Without the mods, the no-antenna S-meter reading could be as high as S7 due to the noise source we've now identified (a voltage regulator). (By the way, this regulator noise had no impact on frequencies about about 500 kHz.) ... __ 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] KBPF3 upgrade kit and instructions now available
Neither the instructions nor the errata speak to the regulator bypass in the KRX3. The instructions do not provide information in either bypass. 73, ... Joe, W4TV On 2015-06-24 8:42 PM, Wayne Burdick wrote: Hi all, The long-promised KBPF3 modification kit is now available. It applies to the KBPF3, K3 RF board, and optionally to the KRX3 sub receiver. It allows the K3 or K3S to receive signals in the 100-500 kHz range with good sensitivity. This is an interesting part of the spectrum, with For full details on the mod kit, see: http://www.elecraft.com/order_form_parts.htm#K3%20Parts Also see below for an excerpt from my original posting about signals in the 100-500 kHz range. 73, Wayne N6KR * * * In honor of the FCC's proposed 2200 meter allocation (137 kHz), we decided to see if we could improve the K3's receive sensitivity in the 100-500 kHz range. This extended coverage is made possible by the new synth (KSYN3A). After a lot of digging, we discovered the cause of the wide-band low-frequency noise. We also found a way to shift the passband of the KBPF3 lower. With a couple of simple modifications, the MDS (minimum discernible signal) can be improved by about 25 dB at the low end (100 kHz). Here are some test results (preamp off, 400-Hz bandwidth): 137 kHz -114 dBm FCC's proposed 2200 meter band 160 kHz -117 dBm low end of the Low-Fer band 250 kHz -126 dBm test frequency in the long-wave beacon band 472 kHz -133 dBm 630 meter experimental band This represents an improvement throughout the range, but especially at the low end. I believe -114 dBm MDS should suffice at 137 kHz, given the high band noise in this range. Another indication of how well the mods work: With no antenna connoted, the K3's S-meter now just barely flickers (S1) at 100 kHz. Without the mods, the no-antenna S-meter reading could be as high as S7 due to the noise source we've now identified (a voltage regulator). (By the way, this regulator noise had no impact on frequencies about about 500 kHz.) ... __ 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...@subich.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] KBPF3 upgrade kit and instructions now available
Will new orders for the KBPF3 have the modification already done or would one need to purchase both the KBPF3 and the KBPF3MDKT if they wanted to receive 100-500 kHz? Mike KI0HA On 6/24/2015 7:42 PM, Wayne Burdick wrote: Hi all, The long-promised KBPF3 modification kit is now available. It applies to the KBPF3, K3 RF board, and optionally to the KRX3 sub receiver. It allows the K3 or K3S to receive signals in the 100-500 kHz range with good sensitivity. This is an interesting part of the spectrum, with For full detailms on the mod kit, see: http://www.elecraft.com/order_form_parts.htm#K3%20Parts Also see below for an excerpt from my original posting about signals in the 100-500 kHz range. 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
Re: [Elecraft] KBPF3 upgrade kit and instructions now available
On Jun 24, 2015, at 9:23 PM, Michael Eberle mtebe...@mchsi.com wrote: Will new orders for the KBPF3 have the modification already done… Yes. That's the KBPF3A. 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
