Re: [Elecraft] K3 - diversity reception question
Wayne, wayne burdick schrieb am 31 Jan 2009 um 9:33: This is about an 8 dB drop. The first 3 dB can be attributed to the fact that main and sub are now sharing the main antenna path (the splitter gets turned on). The other 5 dB must be due to some combination of the other factors I listed: 1. band-pass filter alignment and losses 2. 1st mixer loss 3. crystal filter loss 4. crystal filter ripple 5. physical alignment of the SUB AF control (when used as main/sub BALANCE) Are the crystal filters in the two receivers matched? If not, you could be using a filter with a lot of loss in the sub vs. the main at a particular bandwidth. no - they are not. I have -0.89 and -0.81 - both set to -0.85. I'll discuss this with Gary like you said. tnx, 73! de Werner OE9FWV 73! de Werner OE9FWV -- I can't walk on water, but I can stagger on alcohol. Email powered by Pegasus Mail free at http://www.pmail.com Homepage: http://www.qsl.net/oe9fwv/ Fone +43 5522 75013 Fax +43 5522 75013 15 Mobile +43 664 6340014 Elecraft K2 #5203 K3 #656 __ 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
Re: [Elecraft] K3 - diversity reception question
hi Wayne, wayne burdick schrieb am 30 Jan 2009 um 13:29: Using the MAIN antenna for the subreceiver switches in a -3 dB pad, which is required to split the path to the two receivers. This results in about a 3 dB signal attenuation in both. This may be part of what you're hearing. There also may be slight differences in overall path gain between the two receivers, even when configured identically. Here are some contributing factors: 1. band-pass filter alignment and losses 2. 1st mixer loss 3. crystal filter loss 4. crystal filter ripple 5. physical alignment of the SUB AF control (when used as main/sub BALANCE) 6. ears It's quite plausible that overall receive gain could, therefore, differ by a few dB between main and sub receivers. You could use the K3's built-in true-RMS AF voltmeter functions to determine the exact amount, on each band (AFV/dBV). I think I need some help with this. I have connected a noise gernerator to my ANT1 and I see AFV floating between 622 and 702 with SUB engaged, and 1578 and 1719 without SUB. (this was on 3.670 kHz) 73! de Werner OE9FWV -- Foreploy: Any misrepresentation about yourself for the purpose of obtaining sex. Email powered by Pegasus Mail free at http://www.pmail.com Homepage: http://www.qsl.net/oe9fwv/ Fone +43 5522 75013 Fax +43 5522 75013 15 Mobile +43 664 6340014 Elecraft K2 #5203 K3 #656 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K3 - diversity reception question
hi Jo, you are right I can compensate for the volume loss with the filter gain on the SUB RX. But it takes 8 dB to hear the signal in the middle... 73! de Werner OE9FWV Joe Planisky schrieb am 30 Jan 2009 um 13:26: Maybe you have (or need?) different filter gains between the main and sub filters? 73 -- Joe KB8AP On Jan 30, 2009, at 8:32 AM, Dr. Werner Furlan wrote: Maybe this has been discussed before, if so please forgive me... When I switch on the Sub receiver listening on the headphones, the right channel disappears for a short instance, then comes back but with a slightly lower volume than the left (main RX) channel. Is this intended? I use the Sub knob as balance pot. I have shared Ant 1 with the Sub receiver. 73! de Werner OE9FWV -- If you try to fail, and succeed, which have you done? Email powered by Pegasus Mail free at http://www.pmail.com Homepage: http://www.qsl.net/oe9fwv/ Fone +43 5522 75013 Fax +43 5522 75013 15 Mobile +43 664 6340014 Elecraft K2 #5203 K3 #656 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K3 - diversity reception question
This is about an 8 dB drop. The first 3 dB can be attributed to the fact that main and sub are now sharing the main antenna path (the splitter gets turned on). The other 5 dB must be due to some combination of the other factors I listed: 1. band-pass filter alignment and losses 2. 1st mixer loss 3. crystal filter loss 4. crystal filter ripple 5. physical alignment of the SUB AF control (when used as main/sub BALANCE) Are the crystal filters in the two receivers matched? If not, you could be using a filter with a lot of loss in the sub vs. the main at a particular bandwidth. I'll be out of town for a few days, so you might want to check with Gary about how to isolate which of the above is causing the loss. You can try different bands and filters, for example. Wayne N6KR On Jan 31, 2009, at 3:06 AM, Dr. Werner Furlan wrote: I think I need some help with this. I have connected a noise gernerator to my ANT1 and I see AFV floating between 622 and 702 with SUB engaged, and 1578 and 1719 without SUB. (this was on 3.670 kHz) 73! de Werner OE9FWV -- Foreploy: Any misrepresentation about yourself for the purpose of obtaining sex. Email powered by Pegasus Mail free at http://www.pmail.com Homepage: http://www.qsl.net/oe9fwv/ Fone +43 5522 75013 Fax +43 5522 75013 15 Mobile +43 664 6340014 Elecraft K2 #5203 K3 #656 --- http://www.elecraft.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
[Elecraft] K3 - diversity reception question
Maybe this has been discussed before, if so please forgive me... When I switch on the Sub receiver listening on the headphones, the right channel disappears for a short instance, then comes back but with a slightly lower volume than the left (main RX) channel. Is this intended? I use the Sub knob as balance pot. I have shared Ant 1 with the Sub receiver. 73! de Werner OE9FWV -- There are very few personal problems that cannot be solved through a suitable application of high explosives. Email powered by Pegasus Mail free at http://www.pmail.com Homepage: http://www.qsl.net/oe9fwv/ Fone +43 5522 75013 Fax +43 5522 75013 15 Mobile +43 664 6340014 Elecraft K2 #5203 K3 #656 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K3 - diversity reception question
Hi Werner, Use BSET to see what the sub receiver's PRE and ATTN settings are. They are independent of the main receiver's settings. They are also saved per-band. 73, Wayne N6KR On Jan 30, 2009, at 8:32 AM, Dr. Werner Furlan wrote: Maybe this has been discussed before, if so please forgive me... When I switch on the Sub receiver listening on the headphones, the right channel disappears for a short instance, then comes back but with a slightly lower volume than the left (main RX) channel. Is this intended? I use the Sub knob as balance pot. I have shared Ant 1 with the Sub receiver. --- http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K3 - diversity reception question
hi Wayne, thank you for your answer and suggestion but - the difference in volume is much less than 10db. When I switch from Main to Sub the sound in my head shifts about 10 or 20 deg to the left. With the balance potentiometer I can correct it of course. First I thought my ears are different, but if I change the orientation of my headphones it is shifting to the other side. The main receiver is definitely a bit louder than the sub RX. (but less than 10dB PRE or ATT) I have been listening with the stock 2.7 filters in Main and Sub btw. 73! de Werner OE9FWV wayne burdick schrieb am 30 Jan 2009 um 8:41: Hi Werner, Use BSET to see what the sub receiver's PRE and ATTN settings are. They are independent of the main receiver's settings. They are also saved per-band. 73, Wayne N6KR On Jan 30, 2009, at 8:32 AM, Dr. Werner Furlan wrote: Maybe this has been discussed before, if so please forgive me... When I switch on the Sub receiver listening on the headphones, the right channel disappears for a short instance, then comes back but with a slightly lower volume than the left (main RX) channel. Is this intended? I use the Sub knob as balance pot. I have shared Ant 1 with the Sub receiver. --- http://www.elecraft.com -- What has four legs and an arm? A happy pit bull. Email powered by Pegasus Mail free at http://www.pmail.com Homepage: http://www.qsl.net/oe9fwv/ Fone +43 5522 75013 Fax +43 5522 75013 15 Mobile +43 664 6340014 Elecraft K2 #5203 K3 #656 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K3 - diversity reception question
Maybe you have (or need?) different filter gains between the main and sub filters? 73 -- Joe KB8AP On Jan 30, 2009, at 8:32 AM, Dr. Werner Furlan wrote: Maybe this has been discussed before, if so please forgive me... When I switch on the Sub receiver listening on the headphones, the right channel disappears for a short instance, then comes back but with a slightly lower volume than the left (main RX) channel. Is this intended? I use the Sub knob as balance pot. I have shared Ant 1 with the Sub receiver. 73! de Werner OE9FWV ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K3 - diversity reception question
Dr. Werner Furlan wrote: hi Wayne, thank you for your answer and suggestion but - the difference in volume is much less than 10db. Using the MAIN antenna for the subreceiver switches in a -3 dB pad, which is required to split the path to the two receivers. This results in about a 3 dB signal attenuation in both. This may be part of what you're hearing. There also may be slight differences in overall path gain between the two receivers, even when configured identically. Here are some contributing factors: 1. band-pass filter alignment and losses 2. 1st mixer loss 3. crystal filter loss 4. crystal filter ripple 5. physical alignment of the SUB AF control (when used as main/sub BALANCE) 6. ears It's quite plausible that overall receive gain could, therefore, differ by a few dB between main and sub receivers. You could use the K3's built-in true-RMS AF voltmeter functions to determine the exact amount, on each band (AFV/dBV). 73, Wayne N6KR --- http://www.elecraft.com ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K3 Diversity Reception Question
Hi Mike, The synthesizer in the second RX is locked to the same TCXO reference as the primary K3 rx. 73, Eric WA6HHQ Mike Scott wrote: Is there one or two local oscillators in a two receiver K3? I have been puzzling over the stated ability of the K3 to achieve diversity reception (single signal two independent antennas). For this to work I believe that the subreceiver 8+ MHz local oscillator and the DDS VFO must be in phase lock with the main receiver. I think I read that the subreceiver DDS VFO can be slaved to the main receiver and I assume this means the two VFOs can be in phase lock. I have not read anything about phase locking the local oscillator of the sub receiver to the main receiver or if a single local oscillator is common to both receivers. If this isn't the case diversity reception won't work properly unless the phase difference of the two local oscillators is possibly compensated for in the signal processing chain. Mike Scott AE6WA ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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] K3 Diversity Reception Question
Is there one or two local oscillators in a two receiver K3? I have been puzzling over the stated ability of the K3 to achieve diversity reception (single signal two independent antennas). For this to work I believe that the subreceiver 8+ MHz local oscillator and the DDS VFO must be in phase lock with the main receiver. I think I read that the subreceiver DDS VFO can be slaved to the main receiver and I assume this means the two VFOs can be in phase lock. I have not read anything about phase locking the local oscillator of the sub receiver to the main receiver or if a single local oscillator is common to both receivers. If this isn't the case diversity reception won't work properly unless the phase difference of the two local oscillators is possibly compensated for in the signal processing chain. Mike Scott AE6WA Tarzana, CA Elecraft KX1 40M Inverted V 20M Dipole ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: [Elecraft] K3 Diversity Reception Question
Hi Mike, This was asked and answered three days ago on-list, and is now on the K3 FAQ: Q: Is it possible to phase lock the two K3 receivers? A: They run off the same reference oscillator and are phase locked. There is also at least one other FAQ item addressing diversity recpetion. Bill / W5WVO Mike Scott wrote: Is there one or two local oscillators in a two receiver K3? I have been puzzling over the stated ability of the K3 to achieve diversity reception (single signal two independent antennas). For this to work I believe that the subreceiver 8+ MHz local oscillator and the DDS VFO must be in phase lock with the main receiver. I think I read that the subreceiver DDS VFO can be slaved to the main receiver and I assume this means the two VFOs can be in phase lock. I have not read anything about phase locking the local oscillator of the sub receiver to the main receiver or if a single local oscillator is common to both receivers. If this isn't the case diversity reception won't work properly unless the phase difference of the two local oscillators is possibly compensated for in the signal processing chain. Mike Scott AE6WA Tarzana, CA Elecraft KX1 40M Inverted V 20M Dipole ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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: Elecraft@mailman.qth.net 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
