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 <a...@elecraft.com> 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 <w...@comcast.net> > Reply-to: lp-...@yahoogroups.com > To: lp-...@yahoogroups.com > Cc: w...@comcast.net > 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: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
