Re: [Elecraft] K3: listening to both rcvrs - Reduced receiver noise floor
Tayloe Dan-P26412 wrote: single composite receiver with a lower noise floor. If you added just enough RF pre-amplification to overcome the signal splitting loss to N receivers, adding more and more receivers Only if the pre-amplifiers are noiseless, or at least contribute equivalent input noise power that is much less than the equivalent power generated by the receiver times their gain. In that case, you could do better by using the pre-amp on one receiver and dumping the excess gain later in the system. That's better in noise, but you may compromise dynamic range more. in parallel will produce a composite receiver that has a better and better noise floor. This is in essence what the space telescope folks do. They gang many dishes and many receivers together across a very large area to get an enhancement on the signal and space noise and a suppression of the effective receiver noise contribution. In this case, there is no splitting loss, and the noise is uncorrelated because it is being received at different locations. -- David Woolley The Elecraft list is a forum for the discussion of topics related to Elecraft products and more general topics related ham radio List Guidelines http://www.elecraft.com/elecraft_list_guidelines.htm ___ 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: listening to both rcvrs - Reduced receiver noise floor
On Tue, 18 Nov 2008 08:03:53 +, David Woolley (E.L) wrote: In this case, there is no splitting loss, and the noise is uncorrelated because it is being received at different locations. It's a risky to assume that ALL RX noise is uncorrelated after being detected. While there may be differences in RF level due to antenna displacement and transmission line length, the detected audio may be correlated if some specific noise source is heard by both receivers. In other words, noise can be random or correlated. Examples: an impulse noise generated from a power line or hash generated by a swithing power supply. While both are broadband sources, they are NOT random. If both antennas hear a source like them, the detected audio will be correlated between the two receivers! So in that case, there's no advantage from combining the two RX outputs. The 3 dB advantage arises when the noise is truly random, like the noise preamps that are not common to the two receivers. 73, Jim Brown K9YC ___ 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: listening to both rcvrs
Vic K2VCO wrote: Joe Subich, W4TV wrote: The K3 receivers are better isolated that other dual receiver transceivers. It would be a shame to degrade S/N by adding a mix control when it is relatively easy to do so externally or those who don't mind the hit in S/N. I just tested an experimental feature (I hope I won't be shot for revealing this) which allows you (among other things) to put the main receiver audio into both ears and the sub receiver into one. And this will be an optional menu configuration for those like Joe who may not want to use it. Win-Win for everyone, assuming Elecraft releases it! 73, Bill -- View this message in context: http://n2.nabble.com/K3%3A-listening-to-both-rcvrs-tp1506160p1509310.html Sent from the Elecraft mailing list archive at Nabble.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: listening to both rcvrs
I mentioned this just the other day. By ability to copy the DX station is much reduced when only hearing him/her in one ear. I either have to crank up the main rx AF gain considerably or go back to one rx and use REV. I've used a variety of audio filters over the years--none is necessary with the K3 of course--but have not used an outboard audio mixer. Any recommendations on a mixer which would allow the main rx audio in both ears and the sub in the right ear? Gary W7TEA -- View this message in context: http://n2.nabble.com/K3%3A-listening-to-both-rcvrs-tp1506160p1509772.html Sent from the Elecraft mailing list archive at Nabble.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: listening to both rcvrs
I had the same problem and its due to the 3db drop when dual is on. I believe Dunestar has such a device on their website. http://www.dunestar.com/model842.htm - 73, Greg - AB7R Whidbey Island WA NA-065 On Mon Nov 17 7:10 , W7TEA sent: I mentioned this just the other day. By ability to copy the DX station is much reduced when only hearing him/her in one ear. I either have to crank up the main rx AF gain considerably or go back to one rx and use REV. I've used a variety of audio filters over the years--none is necessary with the K3 of course--but have not used an outboard audio mixer. Any recommendations on a mixer which would allow the main rx audio in both ears and the sub in the right ear? Gary W7TEA -- View this message in context: http://n2.nabble.com/K3%3A-listening-to-both-rcvrs- tp1506160p1509772.html Sent from the Elecraft mailing list archive at Nabble.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 ___ 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: listening to both rcvrs
And of course it just came to me that the problem will still be there when DUAL is on regardless of using the external mixer box or not. :) - 73, Greg - AB7R Whidbey Island WA NA-065 On Mon Nov 17 7:41 , Greg - AB7R sent: I had the same problem and its due to the 3db drop when dual is on. I believe Dunestar has such a device on their website. http://www.dunestar.com/model842.htm - 73, Greg - AB7R Whidbey Island WA NA-065 On Mon Nov 17 7:10 , W7TEA sent: I mentioned this just the other day. By ability to copy the DX station is much reduced when only hearing him/her in one ear. I either have to crank up the main rx AF gain considerably or go back to one rx and use REV. I've used a variety of audio filters over the years--none is necessary with the K3 of course--but have not used an outboard audio mixer. Any recommendations on a mixer which would allow the main rx audio in both ears and the sub in the right ear? Gary W7TEA -- View this message in context: http://n2.nabble.com/K3%3A-listening-to-both-rcvrs- tp1506160p1509772.html Sent from the Elecraft mailing list archive at Nabble.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 ___ 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
Re: [Elecraft] K3: listening to both rcvrs
Greg - AB7R wrote: And of course it just came to me that the problem will still be there when DUAL is on regardless of using the external mixer box or not. :) Greg - AB7R And of course, it is still another external box one has to add just to get any mixing. Mixing that I'd much prefer be in the radio. 73 de Brian/K3KO ___ 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: listening to both rcvrs
Sorry, but I posted to the wrong thread last time. My comments belong here! The Behringer 802 mixer is inexpensive and will do that for you (plus a lot of other stuff) Feed each receiver's audio into the Line IN jack below the microphone jacks. The PAN control will be used to adjust the amount of blend you want. In addition you will have level controls for each channel as well as a single control for the headphone level and another for the main out - lots of flexibility. The downside of the Behringer 802 is that it does not contain a power amplifier, but has more than adequate output for headphones - add a stereo power amplifier if you need or want to drive speakers. 73, Don W3FPR. W7TEA wrote: I mentioned this just the other day. By ability to copy the DX station is much reduced when only hearing him/her in one ear. I either have to crank up the main rx AF gain considerably or go back to one rx and use REV. I've used a variety of audio filters over the years--none is necessary with the K3 of course--but have not used an outboard audio mixer. Any recommendations on a mixer which would allow the main rx audio in both ears and the sub in the right ear? Gary W7TEA ___ 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: listening to both rcvrs
I think the questions regarding addition of noise from one Rx to the other Rx are interesting but not entirely relevant to my own use of the dual receivers for split frequency DXing. Here's the way I normally deal with a split frequency pileup (using a CW pileup as an example). Remember that myself and numerous others copy much better when the signal is coming in BOTH ears (sounds like it's in the middle of the head) as opposed to only ONE ear. We'll say the DX has split a couple of KHz up the band and the pileup is several KHz wide. My main Rx is on the DX and I'm in the split mode with the SUB Rx ON (I will transmit on the sub Rx freq). The main Rx is set very narrow (usually 100 - 300 Hz wide). The sub Rx is set about a KHz or more wide so I can hear a greater swath of pileup signals and listen for the station the DX is currently working. Here's how I run the audio with the Orion or Kenwood (using headphones): Left Ear: Main Rx ONLY (DX station only, NO added noise from the sub Rx) Right Ear: Main + Sub Rx (combine the two in phase) This is also my Tx frequency. Here is what my brain perceives: The DX is in the middle of my head and is easy to decipher (much easier for me than if the DX was only out to my left). The pileup and most of the noise are outside of my head, somewhere to my right side. It becomes a simple matter to pay attention to the right side pileup and tune for a responding signal while the DX station is not transmitting. Even though the pileup may not quit calling while the DX station sends, when the DX station is on, it is very easy to ignore the noise out to the right side and concentrate on what the DX station is sending in the middle of my head. Even with the weakest DX signals, I seldom ever turn off the sub Rx. The noise is simply ignored in my head at the appropriate times. When scanning the pileup for the workee on the right side, it is not necessary to achieve a solid copy but only to recognize that magic 599 TU report. Then you know you are nearly on the spot the DX station is currently monitoring. The additional noise added into the right side from the main Rx is not really an issue and, in fact, it only becomes harder to copy stations in the pileup during the DX stations' transmissions. That's not really a bad thing since the DX station achieves a perception priority over the bedlam of the pileup. The DX is in BOTH ears. The noise is only in ONE ear. If the DX is in the left ear only, it only achieves, at best, parity with the pileup in the right. By the way, the bedlam of the pileup is usually many dB louder than the typical band noise so the discussions of additive noise floors are really about a miner annoyance compared to hundreds of transmitters pounding out their calls in the pileup. Depending on the loudness of the pileup and how well your brain has adapted to this system, you simply adjust the sub Rx volume so that it doesn't detract from the copy of the DX station. That way, for me, the DX station always achieves the magic priority over the pileup in my organic signal decoder. I currently run the K3 with stereo speakers. I set in front of the left speaker and place the right speaker at my far right. For me, it works better for copying the DX than using the headphones with the DX only on the left side. It's the simplest of audio mixers. An SSB pileup is handled the similarly except the passband of the sub Rx is not opened up beyond normal voice response. I surely would like to use the cans so I can get rid of the computer and fan noise! Anyway, that's the way my brain does it best. Good DX, Mike, AB9V ___ 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: listening to both rcvrs
for what it may be worth... For my pair-of-K2's in SO2R, I have routed the audio in such a way that I have a balance control with the audio from the two radios. I call it a mixing control. I find that optimum is achieved when the full strength audio is in one ear, and that same audio is present, but weak in the other ear. I reason that when the audio goes to one ear only, the content must get to the other hemisphere of the brain within brain circuitry. When it is routed to both ears, now both hemispheres get the information for interpretation at the same time. Making it strong in one ear and weak in the other, reversed for the other channel, lets me know which rcvr I am hearing, while brain interpretation is at full speed. and so, Wayne... I think that there must be a firmware way either by routing to a panel pot, or probably more simply in a menu, by which the operator can select either complete channel isolation, or both channels to both ears, but with one ear X DB down from the other. (I can't say how much down is best,but I find that it is enough when I can barely notice it. All of a sudden copy is MUCH easier). Give it a thought because of the above, I, at least, am quite convinced after a lot of usage with a pair of K2's in SO2R, that is a much better arrangement for copying CW from the two channels. with much appreciation for this fine radio, 73, Fd - KT5X K2 # 0700 K3 # 0144___ 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: listening to both rcvrs
If you must pollute the audio from one receiver with audio from the other receiver, add a 5 to 10K pot between the tip and the ring of your headphones and adjust it for the level of pollution you need. There is no need for Wayne (or probably Lyle) to design crosstalk into the DSP process. 73, ... Joe, W4TV -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of cloud runner Sent: Sunday, November 16, 2008 11:03 AM To: elecraft@mailman.qth.net Subject: [Elecraft] K3: listening to both rcvrs for what it may be worth... For my pair-of-K2's in SO2R, I have routed the audio in such a way that I have a balance control with the audio from the two radios. I call it a mixing control. I find that optimum is achieved when the full strength audio is in one ear, and that same audio is present, but weak in the other ear. I reason that when the audio goes to one ear only, the content must get to the other hemisphere of the brain within brain circuitry. When it is routed to both ears, now both hemispheres get the information for interpretation at the same time. Making it strong in one ear and weak in the other, reversed for the other channel, lets me know which rcvr I am hearing, while brain interpretation is at full speed. and so, Wayne... I think that there must be a firmware way either by routing to a panel pot, or probably more simply in a menu, by which the operator can select either complete channel isolation, or both channels to both ears, but with one ear X DB down from the other. (I can't say how much down is best,but I find that it is enough when I can barely notice it. All of a sudden copy is MUCH easier). Give it a thought because of the above, I, at least, am quite convinced after a lot of usage with a pair of K2's in SO2R, that is a much better arrangement for copying CW from the two channels. with much appreciation for this fine radio, 73, Fd - KT5X K2 # 0700 K3 # 0144 ___ 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: listening to both rcvrs
Joe, Your comment strikes me as unnecessarily negative. (Pollute? Crosstalk?) I thought Fred's suggestion, coming as it does from a very experienced CW contester, makes a lot of sense. 73, Jim W8ZR -Original Message- From: [EMAIL PROTECTED] [mailto:elecraft- [EMAIL PROTECTED] On Behalf Of Joe Subich, W4TV Sent: Sunday, November 16, 2008 10:09 AM To: 'cloud runner'; 'Elecraft Reflector' Subject: RE: [Elecraft] K3: listening to both rcvrs If you must pollute the audio from one receiver with audio from the other receiver, add a 5 to 10K pot between the tip and the ring of your headphones and adjust it for the level of pollution you need. There is no need for Wayne (or probably Lyle) to design crosstalk into the DSP process. 73, ... Joe, W4TV -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of cloud runner Sent: Sunday, November 16, 2008 11:03 AM To: elecraft@mailman.qth.net Subject: [Elecraft] K3: listening to both rcvrs for what it may be worth... For my pair-of-K2's in SO2R, I have routed the audio in such a way that I have a balance control with the audio from the two radios. I call it a mixing control. I find that optimum is achieved when the full strength audio is in one ear, and that same audio is present, but weak in the other ear. I reason that when the audio goes to one ear only, the content must get to the other hemisphere of the brain within brain circuitry. When it is routed to both ears, now both hemispheres get the information for interpretation at the same time. Making it strong in one ear and weak in the other, reversed for the other channel, lets me know which rcvr I am hearing, while brain interpretation is at full speed. and so, Wayne... I think that there must be a firmware way either by routing to a panel pot, or probably more simply in a menu, by which the operator can select either complete channel isolation, or both channels to both ears, but with one ear X DB down from the other. (I can't say how much down is best,but I find that it is enough when I can barely notice it. All of a sudden copy is MUCH easier). Give it a thought because of the above, I, at least, am quite convinced after a lot of usage with a pair of K2's in SO2R, that is a much better arrangement for copying CW from the two channels. with much appreciation for this fine radio, 73, Fd - KT5X K2 # 0700 K3 # 0144 ___ 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
RE: [Elecraft] K3: listening to both rcvrs
I find pollution of the opposite receiver (unusual way of describing it) to be very beneficial when listening to a dx station and the pileup. Strange as it may seem, it really helps me separate the dx station from the callers. 73 Tim NZ8J -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Joe Subich, W4TV Sent: Sunday, November 16, 2008 12:09 PM To: 'cloud runner'; 'Elecraft Reflector' Subject: RE: [Elecraft] K3: listening to both rcvrs If you must pollute the audio from one receiver with audio from the other receiver, add a 5 to 10K pot between the tip and the ring of your headphones and adjust it for the level of pollution you need. There is no need for Wayne (or probably Lyle) to design crosstalk into the DSP process. 73, ... Joe, W4TV -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of cloud runner Sent: Sunday, November 16, 2008 11:03 AM To: elecraft@mailman.qth.net Subject: [Elecraft] K3: listening to both rcvrs for what it may be worth... For my pair-of-K2's in SO2R, I have routed the audio in such a way that I have a balance control with the audio from the two radios. I call it a mixing control. I find that optimum is achieved when the full strength audio is in one ear, and that same audio is present, but weak in the other ear. I reason that when the audio goes to one ear only, the content must get to the other hemisphere of the brain within brain circuitry. When it is routed to both ears, now both hemispheres get the information for interpretation at the same time. Making it strong in one ear and weak in the other, reversed for the other channel, lets me know which rcvr I am hearing, while brain interpretation is at full speed. and so, Wayne... I think that there must be a firmware way either by routing to a panel pot, or probably more simply in a menu, by which the operator can select either complete channel isolation, or both channels to both ears, but with one ear X DB down from the other. (I can't say how much down is best,but I find that it is enough when I can barely notice it. All of a sudden copy is MUCH easier). Give it a thought because of the above, I, at least, am quite convinced after a lot of usage with a pair of K2's in SO2R, that is a much better arrangement for copying CW from the two channels. with much appreciation for this fine radio, 73, Fd - KT5X K2 # 0700 K3 # 0144 ___ 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 No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.175 / Virus Database: 270.9.4/1792 - Release Date: 11/16/2008 10:04 AM No virus found in this outgoing message. Checked by AVG - http://www.avg.com Version: 8.0.175 / Virus Database: 270.9.4/1792 - Release Date: 11/16/2008 10:04 AM ___ 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: listening to both rcvrs
Mixing BOTH receivers into BOTH ears is not the same and is simply summing the noise, effectively erasing the advantage of the DX operating a split frequency! I can't speak for SO2R contest operation but I've been using a dual receiver setup for DXing for many years. I initially used separate receivers and an external audio mixer, replaced by a TS-950SDX, followed by an Orion and now the K3. The 950 and Orion both allow a mix of the main receiver in BOTH ears while maintaining the sub ONLY in the right ear. I USED THEM THIS WAY! My mental image of this setup is of having the DX station in the middle of my head while the pileup remains outside of my head (only on the right side). Having the bedlam of the pileup outside of my head makes it easier to ignore this noise at the times when I am concentrating on the DX station's transmissions. There is much less need to actually decipher signals in the pileup but only to recognize that you are listening to the station that the DX is currently working as you are hunting for his current QSX frequency. I found this feature to greatly improve my ability to decipher a weak DX station while simultaneously following the bedlam of the (split frequency) pileup. As I recall, the 950 also allowed the main to mix at a reduced level into the other ear which didn't center the primary receiver in my head but still enhanced the ease of copy. Using the K3 is great since the second Rx is the same quality as the primary Rx, unlike my previous two radios. Their secondary receivers were inferior to their main and prone to numerous distortion products which made the pileup bedlam even worse. Since getting the K3 second Rx, I've been trying to retrain my brain to copy the DX station by using just my left ear (signal outside of my head) but it's obviously not as easy as when the copy signal is in the middle of my head. If code space permits, it would be really great if the K3 did this function internally as a user option. Obviously, Kenwood and TenTec also found this feature desirable. Otherwise, I will probably just build an external mixer box with headphone amp so I can get the primary signal centered in my head again. Thanks to Elecraft for an already superb radio! ...Mike Joe Subich, W4TV wrote: If you must pollute the audio from one receiver with audio from the other receiver, add a 5 to 10K pot between the tip and the ring of your headphones and adjust it for the level of pollution you need. There is no need for Wayne (or probably Lyle) to design crosstalk into the DSP process. 73, ... Joe, W4TV -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of cloud runner Sent: Sunday, November 16, 2008 11:03 AM To: elecraft@mailman.qth.net Subject: [Elecraft] K3: listening to both rcvrs for what it may be worth... For my pair-of-K2's in SO2R, I have routed the audio in such a way that I have a balance control with the audio from the two radios. I call it a mixing control. I find that optimum is achieved when the full strength audio is in one ear, and that same audio is present, but weak in the other ear. I reason that when the audio goes to one ear only, the content must get to the other hemisphere of the brain within brain circuitry. When it is routed to both ears, now both hemispheres get the information for interpretation at the same time. Making it strong in one ear and weak in the other, reversed for the other channel, lets me know which rcvr I am hearing, while brain interpretation is at full speed. and so, Wayne... I think that there must be a firmware way either by routing to a panel pot, or probably more simply in a menu, by which the operator can select either complete channel isolation, or both channels to both ears, but with one ear X DB down from the other. (I can't say how much down is best,but I find that it is enough when I can barely notice it. All of a sudden copy is MUCH easier). Give it a thought because of the above, I, at least, am quite convinced after a lot of usage with a pair of K2's in SO2R, that is a much better arrangement for copying CW from the two channels. with much appreciation for this fine radio, 73, Fd - KT5X K2 # 0700 K3 # 0144 ___ 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
RE: [Elecraft] K3: listening to both rcvrs
All, Cross-over audio between the Main and Sub receiver is part of the menu in a FT1000MP from 1996. (as a lot of you people probably know) You can choose it in the menu how you want the audio: seperate, mono-mixed or bit of stereo cross-over. Absolutely wonderful. There have been several other wishes on the Elecraft-reflector that were implemented. No need to block this wish by calling names of Elecraft people. 73 Arie PA3A -Oorspronkelijk bericht- If you must pollute the audio from one receiver with audio from the other receiver, add a 5 to 10K pot between the tip and the ring of your headphones and adjust it for the level of pollution you need. There is no need for Wayne (or probably Lyle) to design crosstalk into the DSP process. ___ 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: listening to both rcvrs
Jim, Unless one is using diversity with phase locked signals, adding the uncorrelated noise from one receiver to the signal from the other receiver reduces the overall s/n. While you may think my use of the term pollution is unnecessarily negative, it is an accurate description. Assuming equal volume settings and equal bandwidths in the two receivers, the S/N will degrade by 6 dB (twice the noise voltage). If one is listening to a desired DX station with a low noise antenna and the pile-up with a wider filter and a noisy transmit antenna, the S/N will be degraded even more. The K3 receivers are better isolated that other dual receiver transceivers. It would be a shame to degrade S/N by adding a mix control when it is relatively easy to do so externally or those who don't mind the hit in S/N. 73, ... Joe, W4TV -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Dr. James C. Garland Sent: Sunday, November 16, 2008 12:19 PM To: elecraft@mailman.qth.net Subject: RE: [Elecraft] K3: listening to both rcvrs Joe, Your comment strikes me as unnecessarily negative. (Pollute? Crosstalk?) I thought Fred's suggestion, coming as it does from a very experienced CW contester, makes a lot of sense. 73, Jim W8ZR -Original Message- From: [EMAIL PROTECTED] [mailto:elecraft- [EMAIL PROTECTED] On Behalf Of Joe Subich, W4TV Sent: Sunday, November 16, 2008 10:09 AM To: 'cloud runner'; 'Elecraft Reflector' Subject: RE: [Elecraft] K3: listening to both rcvrs If you must pollute the audio from one receiver with audio from the other receiver, add a 5 to 10K pot between the tip and the ring of your headphones and adjust it for the level of pollution you need. There is no need for Wayne (or probably Lyle) to design crosstalk into the DSP process. 73, ... Joe, W4TV -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of cloud runner Sent: Sunday, November 16, 2008 11:03 AM To: elecraft@mailman.qth.net Subject: [Elecraft] K3: listening to both rcvrs for what it may be worth... For my pair-of-K2's in SO2R, I have routed the audio in such a way that I have a balance control with the audio from the two radios. I call it a mixing control. I find that optimum is achieved when the full strength audio is in one ear, and that same audio is present, but weak in the other ear. I reason that when the audio goes to one ear only, the content must get to the other hemisphere of the brain within brain circuitry. When it is routed to both ears, now both hemispheres get the information for interpretation at the same time. Making it strong in one ear and weak in the other, reversed for the other channel, lets me know which rcvr I am hearing, while brain interpretation is at full speed. and so, Wayne... I think that there must be a firmware way either by routing to a panel pot, or probably more simply in a menu, by which the operator can select either complete channel isolation, or both channels to both ears, but with one ear X DB down from the other. (I can't say how much down is best,but I find that it is enough when I can barely notice it. All of a sudden copy is MUCH easier). Give it a thought because of the above, I, at least, am quite convinced after a lot of usage with a pair of K2's in SO2R, that is a much better arrangement for copying CW from the two channels. with much appreciation for this fine radio, 73, Fd - KT5X K2 # 0700 K3 # 0144 ___ 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 ___ 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: listening to both rcvrs
On Nov 16, 2008, at 1:52 PM, Joe Subich, W4TV wrote: Assuming equal volume settings and equal bandwidths in the two receivers, the S/N will degrade by 6 dB (twice the noise voltage). Unless the noise is correlated, the probability density function from summing two random variables causes variances (noise power), not the standard deviations (noise amplitude), to add. So the reduction in SNR (assuming equal noise power) is 3.01 dB, not 6 dB. 73 Chen, W7AY ___ 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: listening to both rcvrs
From my perspective of 20+ years of doing this, I stand firmly by my statement that having the weak, noisy DX in the middle of my head (both ears) makes it easier for me to copy in conjunction with the pileup noise than copying with the DX out to the left with the pileup noise to the right. Thats my observation. It works best FOR ME! It doesn't mean others are the same. Remember that the brain is the ultimate mixer and filter and mine adapts to pulling out the weak DX from the noise best when it's in the middle of my head. Yes, turning off the sub to copy the main is a better situation for copying the DX. That's not the issue. */I'm trying to simultaneously listen to the pileup too! /* This works for me! your theories are fine for the physics of electronics up to the headphones. It's what happens after the sound energy goes into the ears that is my issue. My brain halves are still connected to each other and separate ear feeds probably recombine in the brain differently for different people! I'm only stating how I, as a long time dual receiver user, can best use the second receiver in the split weak DX pile-up situation.. Kenwood, TenTec and apparently Yeasu realize this too. Mike DXCC #1Honor Roll from a noisy city lot Joe Subich, W4TV wrote: Jim, Unless one is using diversity with phase locked signals, adding the uncorrelated noise from one receiver to the signal from the other receiver reduces the overall s/n. While you may think my use of the term pollution is unnecessarily negative, it is an accurate description. Assuming equal volume settings and equal bandwidths in the two receivers, the S/N will degrade by 6 dB (twice the noise voltage). If one is listening to a desired DX station with a low noise antenna and the pile-up with a wider filter and a noisy transmit antenna, the S/N will be degraded even more. The K3 receivers are better isolated that other dual receiver transceivers. It would be a shame to degrade S/N by adding a mix control when it is relatively easy to do so externally or those who don't mind the hit in S/N. 73, ... Joe, W4TV -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Dr. James C. Garland Sent: Sunday, November 16, 2008 12:19 PM To: elecraft@mailman.qth.net Subject: RE: [Elecraft] K3: listening to both rcvrs Joe, Your comment strikes me as unnecessarily negative. (Pollute? Crosstalk?) I thought Fred's suggestion, coming as it does from a very experienced CW contester, makes a lot of sense. 73, Jim W8ZR -Original Message- From: [EMAIL PROTECTED] [mailto:elecraft- [EMAIL PROTECTED] On Behalf Of Joe Subich, W4TV Sent: Sunday, November 16, 2008 10:09 AM To: 'cloud runner'; 'Elecraft Reflector' Subject: RE: [Elecraft] K3: listening to both rcvrs If you must pollute the audio from one receiver with audio from the other receiver, add a 5 to 10K pot between the tip and the ring of your headphones and adjust it for the level of pollution you need. There is no need for Wayne (or probably Lyle) to design crosstalk into the DSP process. 73, ... Joe, W4TV -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of cloud runner Sent: Sunday, November 16, 2008 11:03 AM To: elecraft@mailman.qth.net Subject: [Elecraft] K3: listening to both rcvrs for what it may be worth... For my pair-of-K2's in SO2R, I have routed the audio in such a way that I have a balance control with the audio from the two radios. I call it a mixing control. I find that optimum is achieved when the full strength audio is in one ear, and that same audio is present, but weak in the other ear. I reason that when the audio goes to one ear only, the content must get to the other hemisphere of the brain within brain circuitry. When it is routed to both ears, now both hemispheres get the information for interpretation at the same time. Making it strong in one ear and weak in the other, reversed for the other channel, lets me know which rcvr I am hearing, while brain interpretation is at full speed. and so, Wayne... I think that there must be a firmware way either by routing to a panel pot, or probably more simply in a menu, by which the operator can select either complete channel isolation, or both channels to both ears, but with one ear X DB down from the other. (I can't say how much down is best,but I find that it is enough when I can barely notice it. All of a sudden copy is MUCH easier). Give it a thought because of the above, I, at least, am quite convinced after a lot of usage with a pair of K2's in SO2R, that is a much better arrangement for copying CW from the two channels. with much appreciation for this fine radio, 73, Fd - KT5X K2 # 0700
Re: [Elecraft] K3: listening to both rcvrs
Joe Subich, W4TV wrote: The K3 receivers are better isolated that other dual receiver transceivers. It would be a shame to degrade S/N by adding a mix control when it is relatively easy to do so externally or those who don't mind the hit in S/N. I just tested an experimental feature (I hope I won't be shot for revealing this) which allows you (among other things) to put the main receiver audio into both ears and the sub receiver into one. There is no question that this made it possible to copy a weak DX station much better while still listening to the pileup. Please note that Elecraft has/have not indicated that they will implement it or if so, when. -- 73, Vic, K2VCO Fresno CA http://www.qsl.net/k2vco ___ 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: listening to both rcvrs
That feature would be desireable for me... --... ...-- Dale - WC7S in Wy Date: Sun, 16 Nov 2008 15:57:19 -0800 From: [EMAIL PROTECTED] To: [EMAIL PROTECTED] Subject: Re: [Elecraft] K3: listening to both rcvrs CC: elecraft@mailman.qth.net Joe Subich, W4TV wrote: The K3 receivers are better isolated that other dual receiver transceivers. It would be a shame to degrade S/N by adding a mix control when it is relatively easy to do so externally or those who don't mind the hit in S/N. I just tested an experimental feature (I hope I won't be shot for revealing this) which allows you (among other things) to put the main receiver audio into both ears and the sub receiver into one. There is no question that this made it possible to copy a weak DX station much better while still listening to the pileup. _ Windows Live Hotmail now works up to 70% faster. http://windowslive.com/Explore/Hotmail?ocid=TXT_TAGLM_WL_hotmail_acq_faster_112008___ 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: listening to both rcvrs
So the reduction in SNR (assuming equal noise power) is 3.01 dB, not 6 dB. That's the best case if the noise power is equal. If the other receiver has higher noise power (wider bandwidth, more interfering signals, etc.) the S/N reduction is greater. Even 3 dB reduction in S/N is a big hit if the DX Station you're trying to hear is at or just below the noise level. It would be a shame to turn a top performing radio into a mid-pack device by mixing the audio - because of some old wife's tail. Let those who want mixing do it externally so it doesn't impose a S/N penalty otherwise. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Kok Chen Sent: Sunday, November 16, 2008 5:10 PM To: Elecraft Reflector Subject: Re: [Elecraft] K3: listening to both rcvrs On Nov 16, 2008, at 1:52 PM, Joe Subich, W4TV wrote: Assuming equal volume settings and equal bandwidths in the two receivers, the S/N will degrade by 6 dB (twice the noise voltage). Unless the noise is correlated, the probability density function from summing two random variables causes variances (noise power), not the standard deviations (noise amplitude), to add. So the reduction in SNR (assuming equal noise power) is 3.01 dB, not 6 dB. 73 Chen, W7AY ___ 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
RE: [Elecraft] K3: listening to both rcvrs
I would assume if one didn't want to use the new features ( if they become a reality) you wouldn't have to. I can't imagine it would be an situation that would eliminate the current functionality in favor of something different. Seems like it should please everyone if both options are available. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Joe Subich, W4TV Sent: Sunday, November 16, 2008 7:06 PM To: 'Kok Chen'; 'Elecraft Reflector' Subject: RE: [Elecraft] K3: listening to both rcvrs So the reduction in SNR (assuming equal noise power) is 3.01 dB, not 6 dB. That's the best case if the noise power is equal. If the other receiver has higher noise power (wider bandwidth, more interfering signals, etc.) the S/N reduction is greater. Even 3 dB reduction in S/N is a big hit if the DX Station you're trying to hear is at or just below the noise level. It would be a shame to turn a top performing radio into a mid-pack device by mixing the audio - because of some old wife's tail. Let those who want mixing do it externally so it doesn't impose a S/N penalty otherwise. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Kok Chen Sent: Sunday, November 16, 2008 5:10 PM To: Elecraft Reflector Subject: Re: [Elecraft] K3: listening to both rcvrs On Nov 16, 2008, at 1:52 PM, Joe Subich, W4TV wrote: Assuming equal volume settings and equal bandwidths in the two receivers, the S/N will degrade by 6 dB (twice the noise voltage). Unless the noise is correlated, the probability density function from summing two random variables causes variances (noise power), not the standard deviations (noise amplitude), to add. So the reduction in SNR (assuming equal noise power) is 3.01 dB, not 6 dB. 73 Chen, W7AY ___ 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 No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.175 / Virus Database: 270.9.4/1792 - Release Date: 11/16/2008 10:04 AM No virus found in this outgoing message. Checked by AVG - http://www.avg.com Version: 8.0.175 / Virus Database: 270.9.4/1792 - Release Date: 11/16/2008 10:04 AM ___ 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: listening to both rcvrs
I don't dispute the idea that adding uncorrelated noise degrades the s/n ratio. However, Fred's suggestion, as I understand it, pertained to contesting, not digging a weak DX signal out of the background noise. Typically, in a contest the problem is QRM from many other stations, with the desired signal many dB above the receiver or atmospheric noise. This is also the situation with much DXing, where the desired signal is plenty strong, but is masked by the pileup. I doubt that physics arguments really pertain to this situation (and as a physicist that's hard for me to admit!). I'd think the psychology of hearing is more pertinent. In any case, an interesting topic, with many interesting comments. 73, Jim W8ZR -Original Message- From: [EMAIL PROTECTED] [mailto:elecraft- [EMAIL PROTECTED] On Behalf Of Joe Subich, W4TV Sent: Sunday, November 16, 2008 5:06 PM To: 'Kok Chen'; 'Elecraft Reflector' Subject: RE: [Elecraft] K3: listening to both rcvrs So the reduction in SNR (assuming equal noise power) is 3.01 dB, not 6 dB. That's the best case if the noise power is equal. If the other receiver has higher noise power (wider bandwidth, more interfering signals, etc.) the S/N reduction is greater. Even 3 dB reduction in S/N is a big hit if the DX Station you're trying to hear is at or just below the noise level. It would be a shame to turn a top performing radio into a mid-pack device by mixing the audio - because of some old wife's tail. Let those who want mixing do it externally so it doesn't impose a S/N penalty otherwise. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Kok Chen Sent: Sunday, November 16, 2008 5:10 PM To: Elecraft Reflector Subject: Re: [Elecraft] K3: listening to both rcvrs On Nov 16, 2008, at 1:52 PM, Joe Subich, W4TV wrote: Assuming equal volume settings and equal bandwidths in the two receivers, the S/N will degrade by 6 dB (twice the noise voltage). Unless the noise is correlated, the probability density function from summing two random variables causes variances (noise power), not the standard deviations (noise amplitude), to add. So the reduction in SNR (assuming equal noise power) is 3.01 dB, not 6 dB. 73 Chen, W7AY ___ 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 ___ 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
