Lousy Tx audio reports using K2
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Happy Holidays All,
Getting lousy SSB tx audio reports on K2, SN 3345. I did the Elecraft-approved 2.6khz bandwith and using the Heil MH2 mic. Specifically, I get reports I don't have enough highs in my tx audio. I use the Spectrograph program to align filters per KSB2 On K2 receive, the audio is outstanding....as good as my ICOM 746pro. Any help will be greatly appreciated!! ____________________________________________________________________________________ Looking for last minute shopping deals? Find them fast with Yahoo! Search. http://tools.search.yahoo.com/newsearch/category.php?category=shopping _______________________________________________ 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: Lousy Tx audio reports using K2
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Eddy Avila wrote:
> Specifically, I get reports I don't have enough highs in my tx audio. I use > the Spectrograph program to align filters per KSB2 Unless your voice is particularly bassy there are a couple of things you can do to try and improve things. First things first though. How does the K2 sound to you on receive? Do you feel there is a lack of high end audio when using the widest audio filter setting? If the audio sounds ok to you, it might not be a problem with your radio. One of the simplest things you could try (if you feel it is your radio) is to adjust the audio filters. Alter the settings to move the upper end of the trace shown in Spectograph towards the higher frequencies. A previous message on this list mentioned that "if you key the transmitter in CAL FIL mode, at least for an SSB FL1 filter, the signal is looped back to the receive side, through the filter". That could allow you a way to adjust the filter settings while listening to your own voice to see for yourself if it sounds bassy. -- Cheers! Kevin. http://www.ve3syb.ca/ |"What are we going to do today, Borg?" Owner of Elecraft K2 #2172 |"Same thing we always do, Pinkutus: | Try to assimilate the world!" #include <disclaimer/favourite> | -Pinkutus & the Borg _______________________________________________ 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: Lousy Tx audio reports using K2
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In reply to this post by Eddy
Eddy,
It is important where you set the audio passband. Normally, there is no lack of high frequency response with the 2.6kHz bandpass. Using Spectrogram to set the SSB filters, I normally recommend that you set markers at 300 Hz and the filter width plus 200 Hz - or in your case, 2800 Hz. Center the FL1 (OP1) passband between those markers and try it out. With most voices and microphones, those settings are correct, and wil work quite well for receive as well. For FL2, I use the variable filter and set it 300 Hz less than FL1 - it is important to measure the actual width with Spectrogram since at wide setting the numbers shown by the K2 are usually incorrect. Set the low frequency corner of all the SSB filter passbands at 300 Hz to maintain intelligibility as the filters are narrowed. If you are 'netting' with other hams at a specific frequency, you should check your dial calibration - if you are not tuned to the actual frequency of the other hams (because your dial calibration is off), it could be that your audio is OK, but you are placing your transmit frequency a bit high or low. The K2 Dial Calibration article on my website http://w3fpr.qrpradio.com can give you the procedure for obtaining good dial calibration. If filter alignment as I have outlined does not solve your problem, you may have a microphone that is lacking in response at the higher audio frequencies, but the MH2 usually has a bit of boost for the highs - you might want to see if one of the locals near you has an MH2 that you can compare with. 73, Don W3FPR Eddy Avila wrote: > Happy Holidays All, > > Getting lousy SSB tx audio reports on K2, SN 3345. I > did the Elecraft-approved 2.6khz bandwith and using > the Heil MH2 mic. > > Specifically, I get reports I don't have enough highs > in my tx audio. I use the Spectrograph program to > align filters per KSB2 > > On K2 receive, the audio is outstanding....as good as > my ICOM 746pro. > > Any help will be greatly appreciated!! > > 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: Lousy Tx audio reports using K2
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In reply to this post by Kevin Cozens-2
-----Original Message----- ...A previous message on this list mentioned that "if you key the transmitter in CAL FIL mode, at least for an SSB FL1 filter, the signal is looped back to the receive side, through the filter". That could allow you a way to adjust the filter settings while listening to your own voice to see for yourself if it sounds bassy. -------------------------- I didn't know about that. When I adjusted my K2, I used a Drake 2B receiver to receive my own transmitted signal. I fed the audio from the Drake into my PC through a good sound card. I then transmitted with the K2 into a dummy load while I listened on the 2B. The recording showed me exactly what another person would have heard and I was able to fine tune my filter adjustment for my voice & mic. I then put the mic away and haven't used SSB since :-). Ah, life as a hopeless CW junkie! - Keith N1AS - - K2 5411.ssb.100 - - K3 Wave 3 - _______________________________________________ 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 Don Wilhelm-4
Good stuff Don!
I'm considering doing the G3RXQ mod to the KSB2 and see if that helps with the low-freq response. 73.......
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Re: Lousy Tx audio reports using K2
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Eddy,
Since you mentioned a lack of highs, I doubt that the low-frequency response mod will help much, but you certainly can try. What is more important is the place the low frequency corner of the FL1 passband close to 300 Hz. If you do that, when you tune an SSB signal so it sounds right in your K2, you will transmit on his frequency (because you tuned his voice to fall into the 300 to 2800 kHz range where it sounds best to most ears). If you OP1 filter is set 100 Hz high or low, then you can still receive by skewing the frequency (you really will not know you are doing that, but it happens that way), but then when you transmit, you do not sound right to the person on the receiving end. When I set up a K2 that is in here for repair, I listen not only to the received signal, but I listen to a transmitted signal on another receiver. I have found that the 300 Hz filter corner (-3 to 6 dB point) is the one most important factor in making transmit and receive line up properly. 73, Don W3FPR k6sdw wrote: > Good stuff Don! > > I'm concerning doing the G3RXQ mod to the KSB2 and see if that helps with > the low-freq response. > > 73....... > > > > Don Wilhelm wrote: > >> Eddy, >> >> It is important where you set the audio passband. Normally, there is no >> lack of high frequency response with the 2.6kHz bandpass. >> >> Using Spectrogram to set the SSB filters, I normally recommend that you >> set markers at 300 Hz and the filter width plus 200 Hz - or in your >> case, 2800 Hz. Center the FL1 (OP1) passband between those markers and >> try it out. With most voices and microphones, those settings are >> correct, and wil work quite well for receive as well. For FL2, I use >> the variable filter and set it 300 Hz less than FL1 - it is important to >> measure the actual width with Spectrogram since at wide setting the >> numbers shown by the K2 are usually incorrect. Set the low frequency >> corner of all the SSB filter passbands at 300 Hz to maintain >> intelligibility as the filters are narrowed. >> >> If you are 'netting' with other hams at a specific frequency, you should >> check your dial calibration - if you are not tuned to the actual >> frequency of the other hams (because your dial calibration is off), it >> could be that your audio is OK, but you are placing your transmit >> frequency a bit high or low. The K2 Dial Calibration article on my >> website http://w3fpr.qrpradio.com can give you the procedure for >> obtaining good dial calibration. >> >> If filter alignment as I have outlined does not solve your problem, you >> may have a microphone that is lacking in response at the higher audio >> frequencies, but the MH2 usually has a bit of boost for the highs - you >> might want to see if one of the locals near you has an MH2 that you can >> compare with. >> >> 73, >> Don W3FPR >> > 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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Don...
When you cite the "-3 to 6dB point," do you mean to say "-3 to -6dB?" That is to say, that the "corner" of the filter response, presumably falling at the "-3 to -6dB point" should be positioned at 300cps. Is this a correct interpretation of your recommendation? Thanks. ...robert At 12/21/2007 16:51, Don Wilhelm wrote: >Eddy, > >Since you mentioned a lack of highs, I doubt that the low-frequency >response mod will help much, but you certainly can try. > >What is more important is the place the low frequency corner of the FL1 >passband close to 300 Hz. If you do that, when you tune an SSB signal so >it sounds right in your K2, you will transmit on his frequency (because >you tuned his voice to fall into the 300 to 2800 kHz range where it sounds >best to most ears). If you OP1 filter is set 100 Hz high or low, then you >can still receive by skewing the frequency (you really will not know you >are doing that, but it happens that way), but then when you transmit, you >do not sound right to the person on the receiving end. > >When I set up a K2 that is in here for repair, I listen not only to the >received signal, but I listen to a transmitted signal on another >receiver. I have found that the 300 Hz filter corner (-3 to 6 dB point) >is the one most important factor in making transmit and receive line up >properly. > >73, >Don W3FPR > >k6sdw wrote: >>Good stuff Don! >> >>I'm concerning doing the G3RXQ mod to the KSB2 and see if that helps with >>the low-freq response. >> >>73....... >> >> >> >>Don Wilhelm wrote: >> >>>Eddy, >>> >>>It is important where you set the audio passband. Normally, there is no >>>lack of high frequency response with the 2.6kHz bandpass. >>> >>>Using Spectrogram to set the SSB filters, I normally recommend that you >>>set markers at 300 Hz and the filter width plus 200 Hz - or in your >>>case, 2800 Hz. Center the FL1 (OP1) passband between those markers and >>>try it out. With most voices and microphones, those settings are >>>correct, and wil work quite well for receive as well. For FL2, I use >>>the variable filter and set it 300 Hz less than FL1 - it is important to >>>measure the actual width with Spectrogram since at wide setting the >>>numbers shown by the K2 are usually incorrect. Set the low frequency >>>corner of all the SSB filter passbands at 300 Hz to maintain >>>intelligibility as the filters are narrowed. >>> >>>If you are 'netting' with other hams at a specific frequency, you should >>>check your dial calibration - if you are not tuned to the actual >>>frequency of the other hams (because your dial calibration is off), it >>>could be that your audio is OK, but you are placing your transmit >>>frequency a bit high or low. The K2 Dial Calibration article on my >>>website http://w3fpr.qrpradio.com can give you the procedure for >>>obtaining good dial calibration. >>> >>>If filter alignment as I have outlined does not solve your problem, you >>>may have a microphone that is lacking in response at the higher audio >>>frequencies, but the MH2 usually has a bit of boost for the highs - you >>>might want to see if one of the locals near you has an MH2 that you can >>>compare with. >>> >>>73, >>>Don W3FPR >>> >_______________________________________________ >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 Robert G. Strickland PhD ABPH - KE2WY [hidden email] Syracuse, New York USA _______________________________________________ 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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