New PowerSDR/IF K3 Video posted
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New PowerSDR/IF K3 Video posted
 
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I see Wim beat me to it, glad to see people are watching ;)
If you have seen the new YouTube video I also posted a High-Def version on my website. http://www.ww2dx.com/WW2DX/Radio_Movies/Entries/2008/7/29_HI-DEF_PowerSDR_IF_Stage_K3_Demo_Part_II.html Hope you enjoy it, more to come. 73 de Lee WW2DX _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: New PowerSDR/IF K3 Video posted
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High Def version MUCH nicer to see what is going on... These are some
pretty exciting enhancements. On Tue, 2008-07-29 at 23:47 -0400, Lee (WW2DX) wrote: > I see Wim beat me to it, glad to see people are watching ;) > > If you have seen the new YouTube video I also posted a High-Def > version on my website. > > http://www.ww2dx.com/WW2DX/Radio_Movies/Entries/2008/7/29_HI-DEF_PowerSDR_IF_Stage_K3_Demo_Part_II.html > > Hope you enjoy it, more to come. > > 73 de Lee > WW2DX > > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: New PowerSDR/IF K3 Video posted
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In reply to this post by Lee J. Imber (WW2DX)
On Tue, 2008-07-29 at 23:47 -0400, Lee (WW2DX) wrote: > > If you have seen the new YouTube video I also posted a High-Def > version on my website. > > http://www.ww2dx.com/WW2DX/Radio_Movies/Entries/2008/7/29_HI-DEF_Power > SDR_IF_Stage_K3_Demo_Part_II.html > > Hope you enjoy it, more to come. > > 73 de Lee > WW2DX > I get an error when trying to view this video in Windows XP: QuickTime files are missing and unfortunately they are not available on the QuickTime site. End result is audio and no video... On the WW2DX site the link to the YouTube video is broken Mike Scott - AE6WA Tarzana, CA (DM04 / near LA) K3-100 #508/ KX1 #1311 _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: New PowerSDR/IF K3 Video posted
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On Jul 30, 2008, at 9:24 AM, Mike Scott wrote: > > > > On Tue, 2008-07-29 at 23:47 -0400, Lee (WW2DX) wrote: >> >> If you have seen the new YouTube video I also posted a High-Def >> version on my website. >> >> http://www.ww2dx.com/WW2DX/Radio_Movies/Entries/2008/7/29_HI- >> DEF_Power >> SDR_IF_Stage_K3_Demo_Part_II.html >> >> Hope you enjoy it, more to come. >> >> 73 de Lee >> WW2DX >> > > > I get an error when trying to view this video in Windows XP: > QuickTime files > are missing and unfortunately they are not available on the > QuickTime site. > End result is audio and no video... You will most likely need Apple's Quicktime player installed. http://www.apple.com/quicktime/download/ > > > On the WW2DX site the link to the YouTube video is broken Yes, looks like youtube does not allow direct linking. I have embedded the video on that page. 73 Lee WW2DX > > > > Mike Scott - AE6WA > Tarzana, CA (DM04 / near LA) > K3-100 #508/ KX1 #1311 > > > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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In reply to this post by Lee J. Imber (WW2DX)
The new KXV3 is installed, the KXV3 is enabled and calibrated as directed by
the instructions. The 2nd antenna input works as expected but my oscilloscope shows no signal (<5 mV) coming from the IF Output on the KXV3. What IF signal level should I be seeing? Don K7FJ _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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> The 2nd antenna input works as expected but my oscilloscope shows no
> signal (<5 mV) coming from the IF Output on the KXV3. What IF signal > level should I be seeing? It will be about the same level as at the antenna, or perhaps less, depending on settings of PRE, ATT, etc. 73, Lyle KK7P _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Problems with K3 KXV3 IF Output Level?
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Good evening Lyle:
I honestly don't know where you're getting those levels from as I already reported to you back in April/08 that the levels at the I F output were pretty well non existent. There is just no tracking of levels at the I F out with what is fed into the antenna input of the receiver. I even used a 15 db amplifier from Jack Smith of Clifton Laboratories without any luck as there is simply no levels to play with there. I believe that Jack Smith also queried you about that without getting a proper reply as yet from you. I realize that nobody is perfect but why are we dogging a proper reply and/or fix for that? Fern with K3 #412 ----- Original Message ----- From: "Lyle Johnson" <[hidden email]> To: "Don Ehrlich" <[hidden email]> Cc: "Elecraft Reflector" <[hidden email]> Sent: Wednesday, July 30, 2008 9:18 PM Subject: Re: [Elecraft] K3 KXV3 IF Output Level? > The 2nd antenna input works as expected but my oscilloscope shows no > signal (<5 mV) coming from the IF Output on the KXV3. What IF signal > level should I be seeing? It will be about the same level as at the antenna, or perhaps less, depending on settings of PRE, ATT, etc. 73, Lyle KK7P _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 270.5.6/1574 - Release Date: 7/25/2008 4:27 PM _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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See N8LP's comments below. My IF OUT level improved ~7.5 dB with his mod which involves changing R8 to 15k and R9 to 50 ohms on the K3 RF Board. 73, Bill Re: [LP-PAN] Re: K3 IF output The NF of LP-PAN by itself is the same as the K3 with preamp off. A signal at about -127dBm (0.1uV) can be heard about equally well with 500 Hz filter above the noise floor of about -135dBm. But the overall NF of LP-PAN depends on the K3. This is because the losses in the K3 mixer / internal buffer add to the NF. In a stock K3, these losses add up to about 17dB. Turning the K3 preamp on helps a lot, since the preamp has low NF and adds gain ahead of the losses, where it has a greater effect on the overall NF. The simple mod I did to my K3 internal buffer reduces the losses by almost 10dB, while only reducing the IP3 of the system by a couple dB. My modified K3 / LP-PAN combo has an overall NF that is below atmospheric noise here on all bands but 10m... with the K3 preamp off. This seems to me to be a reasonable balance of signal handling and sensitivity. Turning the K3 preamp on, without the mod, produces a similar result as I recall. Unless you regularly see signals above -20dBm, leaving the K3 preamp on should not be a problem. I haven't seen a signal that strong here yet, even during FD where I had two stations within a mile of my QTH. I haven't heard anything more from Wayne about the possibility of a running change in the K3 circuit, but the mod is simple to do if you like. It's changing two resistors (actually one can be paralleled to the existing one), similar to doing the HAGC mod. Several users have done it. 73, Larry N8LP |
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In reply to this post by Fern Rivard
> ...There is just no tracking of levels at the I F
> out with what is fed into the antenna input of the receiver. If that were true, LP-PAN, SDR-14 and SDR0IQ could not be used as panadaptors. But they can and are being used, so one can only conclude that the output at the IF jack most assuredly follows the signal at the input. Note that there are a mulititude of signals at the IF output connector since this is the unfiltered output from the mixer post-amplifier. These signals must be accounted for in any device which attaches to the IF output jack. See < URL:http://www.telepostinc.com/LP-PAN.html > and scroll about halfway down the page to "L.O. leakage / isolation:" for details The lower the impedance of the attached load, the lower the gain (or increased loss) there will be at the IF output. We're talking microvolt levels here, not hundreds of millivolts. 73, Lyle KK7P _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: Re: Problems with K3 KXV3 IF Output Level?
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Lyle:
As we have discussed, the K3 does not follow the normal commercial/military practice of providing a 1:1 relationship between the IF sample and the signal level at the antenna port. Since the K3 has a switchable pre-amp, the 1:1 relationship would presumably be with the pre-amp off. As I understand it, there's something like a 15 dB difference between the signal level at the antenna input port and the IF sample out. I'll have a better feel for this when my K3 arrives (ordered in May 2007; has been waiting for the 2nd receiver, maybe shipped in August 2008), but I've had reported to me a couple of measurements in that range. The J310 used to provide the K3's IF sample has a voltage divider on the input that knocks down the signal level from the sample point. In addition, the J310 in source follower mode has an output impedance in the 100-200 ohm range, depending on idle bias current. (Output impedance is 1/gm and gm varies with bias/idle current.) Thus, if connected to a 50 ohm device, such as a spectrum analyzer or a receiver, there's an additional loss in the 10 dB range. Now, a Softrock or Larry's LP-PAN has enough sensitivity to overcome most or all of this loss, but it's still a design error. (The IF sample can also be amplified by an external amplifier such as my Z10000-U. If configured in high Z input mode, the J310's output impedance becomes a non-issue.) Jack K8ZOA www.cliftonlaboratories.com Lyle Johnson wrote: >> ...There is just no tracking of levels at the I F >> out with what is fed into the antenna input of the receiver. > > If that were true, LP-PAN, SDR-14 and SDR0IQ could not be used as > panadaptors. But they can and are being used, so one can only > conclude that the output at the IF jack most assuredly follows the > signal at the input. > > Note that there are a mulititude of signals at the IF output connector > since this is the unfiltered output from the mixer post-amplifier. > These signals must be accounted for in any device which attaches to > the IF output jack. See < URL:http://www.telepostinc.com/LP-PAN.html > > and scroll about halfway down the page to "L.O. leakage / > isolation:" for details > > The lower the impedance of the attached load, the lower the gain (or > increased loss) there will be at the IF output. We're talking > microvolt levels here, not hundreds of millivolts. > > 73, > > Lyle KK7P > > _______________________________________________ > Elecraft mailing list > Post to: [hidden email] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: Problems with K3 KXV3 IF Output Level?
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In reply to this post by Fern Rivard
Fern, I am using the IF output AOK from my K3/KXV3. I am using it
with a Clifton Labs isolation Z10000U buffer/preamp with very low gain into a Softrock40 With a LO of 8191 kHz with WU2X's version of PowerSDR as the panadaptor display, offset by 24 kHz (8215-8191). This with a Delta-44 sound card sampling at 96 kHz. I would estimate that, with a 50 uV signal into the K3, the KXV3 is putting out something in the 20-50 uV range. Using my test oscillator at 1 uV output into the K3, I see an obvious peak on the panadaptor, so the sensitivity is OK. I haven't calibrated PowerSDR levels yet, but it is already near the correct S9 level on the display for 50 uV from my test oscillator into the K3. Connect up another receiver to the KXV3's IF output and see if you don't hear sigs repeated on it when you tune it near 8.215 MHz. If the K3 is hearing sigs, you should hear sigs on that second rx near whatever freq the K3 is tuned to, and their levels will be similar to what the K3 is hearing. This will tell you if your K3/KXV3 is working OK. Keep working on it - the PowerSDR panadaptor is the best I have ever used in 35 years of using panadaptors. Jerry W4UK At 12:08 AM 7/31/2008, Fern Rivard wrote: >Good evening Lyle: > > I honestly don't know where you're getting those levels from as > I already reported to you back in April/08 that the levels at the I > F output were pretty well non existent. There is just no tracking > of levels at the I F out with what is fed into the antenna input of > the receiver. I even used a 15 db amplifier from Jack Smith of > Clifton Laboratories without any luck as there is simply no levels > to play with there. I believe that Jack Smith also queried you > about that without getting a proper reply as yet from you. I > realize that nobody is perfect but why are we dogging a proper > reply and/or fix for that? > Fern with K3 #412 > > > >----- Original Message ----- >From: "Lyle Johnson" <[hidden email]> >To: "Don Ehrlich" <[hidden email]> >Cc: "Elecraft Reflector" <[hidden email]> >Sent: Wednesday, July 30, 2008 9:18 PM >Subject: Re: [Elecraft] K3 KXV3 IF Output Level? > > > > The 2nd antenna input works as expected but my oscilloscope shows no > > signal (<5 mV) coming from the IF Output on the KXV3. What IF signal > > level should I be seeing? > >It will be about the same level as at the antenna, or perhaps less, >depending on settings of PRE, ATT, etc. > >73, > >Lyle KK7P _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: Re: Problems with K3 KXV3 IF Output Level?
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In reply to this post by Jack Smith-6
Hi Jack,
Lyle was referring to tracking of signal levels (i.e. level changes), not absolute gain. In our case, the IF output was designed specifically for internal use by a possible future Elecraft option and fully meets our design needs in this area. It has sufficient signal for this use and clearly works with other external devices that are designed to handle these levels, as noted by Lyle. We were very concerned about having an overly strong IF signal inside the K3 and kept this level as low as possible to avoid additional RX and TX spur generation inside the radio. Our intent was to have it amplified by an external, higher input impedance, amplifier as noted in your email. Regards, Eric Jack Smith wrote: > Lyle: > > As we have discussed, the K3 does not follow the normal > commercial/military practice of providing a 1:1 relationship between > the IF sample and the signal level at the antenna port. Since the K3 > has a switchable pre-amp, the 1:1 relationship would presumably be > with the pre-amp off. > ...... > Now, a Softrock or Larry's LP-PAN has enough sensitivity to overcome > most or all of this loss, but it's still a design error. > > (The IF sample can also be amplified by an external amplifier such as > my Z10000-U. If configured in high Z input mode, the J310's output > impedance becomes a non-issue.) > > Jack K8ZOA > www.cliftonlaboratories.com > > Lyle Johnson wrote: >>> ...There is just no tracking of levels at the I F >>> out with what is fed into the antenna input of the receiver. >> If that were true, LP-PAN, SDR-14 and SDR0IQ could not be used as >> panadaptors. But they can and are being used, so one can only >> conclude that the output at the IF jack most assuredly follows the >> signal at the input. >> >> Note that there are a mulititude of signals at the IF output >> connector since this is the unfiltered output from the mixer >> post-amplifier. These signals must be accounted for in any device >> which attaches to the IF output jack. See < >> URL:http://www.telepostinc.com/LP-PAN.html > and scroll about halfway >> down the page to "L.O. leakage / isolation:" for details >> >> The lower the impedance of the attached load, the lower the gain (or >> increased loss) there will be at the IF output. We're talking >> microvolt levels here, not hundreds of millivolts. >> 73, >> Lyle KK7P >> > Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
Re: Re: Problems with K3 KXV3 IF Output Level?
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Hi All,
I have just connected my TT RX 320 to the IF port on my K3, and there seems to be plenty of signal available. With the K3 on 7030 kHz I could tune the RX320 right through the 41 m broadcast band. The only pecularity is that the RX 320 needs to be tuned lf to go hf and vice versa and usb needs to be selected on 40m ssb to resolve the signals. I also tried WinRad on the 320's IF and got a panoramic display working, only 24 kHz wide though. Regards Tim gm4lmh _______________________________________________ Elecraft mailing list Post to: [hidden email] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com |
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