Yes, the P3 assumes it is connected to the main receiver's IF output, so if it is actually connected to the sub-RX it would still work but would not display the correct frequencies and levels. If this becomes popular enough maybe we should think about adding sub-RX support to P3 firmware.
Alan N1AL On Tue, 2010-05-25 at 23:50 -0400, Guy Olinger K2AV wrote: > Wouldn't there be a K3 interoperating with P3 firmware issue with > running the P3 on the sub-RX? Just because you could feed a > **stand-alone** box with a non-company mod for sub-RX IF, does not > mean the P3 would change the sub-RX with a click on the P3. There is a > lot of proprietary communication between the K3 and the P3 over the > serial connection. > > Wouldn't a sub-RX feed to a P3 need to be specifically supported by > Elecraft firmware, both in K3 and P3? Last remarks from them in this > thread were negative, particularly about isolation at a switch. > > That aside, I believe someone using the sub-RX with the TX in split, > while leaving the main RX to feed the P3, would accomplish the same > end. This WOULD be a problem on other rigs where the second RX is an > inferior RX, or not available. In the K3 the sub-RX is a fully equal > clone of the main RX, making various A/B flippity-do tricks possible > without sacrificing performance in any way. > > 73, Guy. > > On Tue, May 25, 2010 at 9:48 PM, Alan Bloom <[email protected]> wrote: > > Hi Rudolf, > > > > At the bottom of this message I will copy a posting from W3SZ on the > > LP-PAN email list that describes how he added IF output to his K3 > > sub-receiver. He used the Z10000 buffer amp from Clifton Labs: > > http://www.cliftonlaboratories.com/z10000_buffer_amp.htm > > > > If you don't mind modifying your K3, it looks like that should allow you > > to use the sub-receiver with a P3. When I get time I'll have to try it > > on my K3 and see how it works. > > > > Alan N1AL > > > > > > > > On Tue, 2010-05-25 at 22:01 +0200, hb9ari wrote: > >> Hi Rich, > >> > >> Very bad news ! > >> > >> That was my 1st idea when ordering the P3 > >> to use it for "wide" span use for phone mode. > >> (50Mhz in priority during possible "apertures") > >> For digi mode, as JT65, the ~2kHz width > >> of "waterfall" is 100% sufficient, because > >> frequencies are well defined (for ex 14.076Mhz) > >> I'm quite sure now that it was a bad idea to have ordered > >> a P3 but, with your accurate explanation, i will > >> renounce to the sub-receiver ordering (and > >> roofing filters)! > >> > >> I regret that a P3 connection to the sub-rcvr > >> is not possible, and, as i'm not an RF engineer, > >> i don't understand the reason(s)! > >> > >> At my point of vue, it's not 100% correct to say that > >> the KRX3 is like a 2nd receiver ! > >> > >> Just in time to stop for the KRX3 ordering but for the P3... > >> may be eBay ? > >> > >> My best 73, > >> Rudolf, HB9ARI > > > > ============================================================ > > > > -------- Forwarded Message -------- > > From: w3sz <[email protected]> > > Reply-to: [email protected] > > To: [email protected] > > Cc: [email protected] > > Subject: [LP-PAN] KRX3 IF tap up and running > > Date: Fri, 02 Jan 2009 00:56:35 -0500 > > > > Hi Larry, > > > > I didn't get a chance to hook up the LP-Pans yet [because the audio > > cables I need are up at my hilltop QTH], but I did install the KRX3 > > and its Z10000 buffer amp, and both the main K3 IF output and the KRX3 > > subreceiver IF output seem to be working fine. I ran the main IF to > > the main receiver on my Flex5000 and the KRX3 subIF to the subreceiver > > on the Flex5000. > > > > Everything seems to be OK in terms of how I chose to get the IF from the > > KRX3. > > > > I am working a long day tomorrow as well as Saturday AM, but I am > > hoping to get a chance to run up to the hilltop and pick up the audio > > cables and then get the LP Pans hooked up Saturday afternoon. > > > > This is a brief summary of what I did with the KRX3: > > > > I used the Z10000 as buffer amp inside the KRX3. > > > > I got +12V from a 12SA pad near to P86A. > > Power and RF connections to the Z10000 were done from the underside of > > the Z10000. > > > > I took IF output from KRX3 from P86A and used RG174U to take this to > > input of Z10000. > > > > I mounted Z10000 on an unused FL position using a 1/2 inch standoff. > > > > I mounted a dual female SMA connector in the REF hole at the bottom > > corner of the K3 just below the official IF out BNC. I then used a > > right angle premade small surplus coaxial cable to take the signal to > > the KRX3 and thus the Z10000. > > > > I entered the KRX3 at the back left corner opposite to J92, because > > there was already an opening there. > > > > I ran the coax inside the KRX3 bottom shell, beneath the main KRX3 > > PCB. I brought it up to the Z10000 by running it through an unused > > hole meant for an FL standoff. > > > > At first check, using the two subreceivers on the Flex5000 to receive > > the IF signals from the K3, the main K3 and the KRX3 subreceiver IF > > outputs seem to be equivalent. > > > > When constructing the Z10000, I used the -U [Universal] options, not > > the K2 options. I chose to set it up for zero gain, and thus chose > > R907 to be 499 ohms, and R905 to be 4.7K, as per section 2.3.3 of the > > Z10000 manual. > > > > I attached a jpg file with the two IFs from the K3 going to the Flex > > 5000. The K3 main IF goes to the main Flex receiver and the DRX3 sub > > IF goes to the Flex sub receiver. The signal is Radio Moscow on 40 > > meters. > > > > 73, > > > > Roger Rehr > > W3SZ > > http://www.nitehawk.com/w3sz > > > > > > > > ______________________________________________________________ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:[email protected] > > > > 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:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
