Re: [Elecraft] [K3] K3 Rev C DSP with Low Freq Enhancement
See: http://n2.nabble.com/K3-skematics-td4021941.html#a4021941 ~Iain / N6ML On Mon, Nov 23, 2009 at 11:37 PM, Jan Holmer SM6TUW sm6...@gmail.com wrote: Lyle, What is the status, will there be a 2009 schematic? 73 Jan SM6TUW KK7P wrote: I think what some folks are requesting is an updated schematic... Approximately every October I gather the latest schematics and integrate them into a PDF document which we post on the website. The original schematic set was Oct 2007, the present set is Oct 2008. When I return from vacation, I'll be gathering the information again for a new schematic release in October or November. 73, Lyle KK7P/7 (Tucson AZ) __ 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 -- View this message in context: http://n2.nabble.com/K3-Rev-C-DSP-with-Low-Freq-Enhancement-ship-date-info-New-swap-out-option-on-parts-order-page-tp3789876p4056289.html Sent from the [K3] mailing list archive at Nabble.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 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] K3 Rev C DSP with Low Freq Enhancement
Lyle, What is the status, will there be a 2009 schematic? 73 Jan SM6TUW KK7P wrote: I think what some folks are requesting is an updated schematic... Approximately every October I gather the latest schematics and integrate them into a PDF document which we post on the website. The original schematic set was Oct 2007, the present set is Oct 2008. When I return from vacation, I'll be gathering the information again for a new schematic release in October or November. 73, Lyle KK7P/7 (Tucson AZ) __ 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 -- View this message in context: http://n2.nabble.com/K3-Rev-C-DSP-with-Low-Freq-Enhancement-ship-date-info-New-swap-out-option-on-parts-order-page-tp3789876p4056289.html Sent from the [K3] mailing list archive at Nabble.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
Re: [Elecraft] [K3] K3 Rev C DSP with Low Freq Enhancement
Wished I had a set of ears like yours. 12 KHz alias signals measure 65 dB down from CW beat note in my K3 while 3rd harmonic is 55 dB down. Juan, I think your 3rd harmonic measurement is the key. If you research audio fatigue you may find that odd harmonics are particularly troublesome and that they can cause audio fatigue even when the level is below what you might consider audible. My ears are not that good, ask my wife... I wear a hearing aid in my left ear. I just may more susceptible to audio fatigue than the next guy. Mike Scott - AE6WA Tarzana, CA (DM04 / near LA) NAQCC 3535 K3-100 #508 / KX1 #1311 __ 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] K3 Rev C DSP with Low Freq Enhancement
Juan, I think your 3rd harmonic measurement is the key. If you research audio fatigue you may find that odd harmonics are particularly troublesome and that they can cause audio fatigue even when the level is below what you might consider audible. Mike, There may be several variables occurring here. When I get back from a conference, I plan on making my own FFT measurements at the H/P jack regarding this effect. It's possible that the intensity of distortion artifacts as measured by Jack Smith, and presumably what you're hearing, may be different among K3 samples. Myself, I don't hear anything that brings about fatigue under any operating conditions. Also, Rx audio response capabilities with the latest K3 firmware has evolved and additional low-end content is present that was not there in previous releases. And so, one has to consider whether it was the change in firmware -- or the beta LPF board that is now responsible for the changes you're now hearing. I have to believe that with some ops, the perception of fatigue is related to a previous lack of low-end to presence-band balance. More than anything, what brings fatigue to me is extended listening through a narrow audio passband. Paul, W9AC __ 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] K3 Rev C DSP with Low Freq Enhancement
Wished I had a set of ears like yours. 12 KHz alias signals measure 65 dB down from CW beat note in my K3 while 3rd harmonic is 55 dB down. 73 Juan EA5RS Mike Scott-7 wrote: I have installed the beta version of the Low Pass filter board. It turned my K3 into a whole different radio. I had been experiencing audio fatigue to the point I just stopped using the K3 for CW. I know Paul says the audio is one of the best designed audio circuits for a communications receiver. I say it is now but not before. I may have had a singular issue with my K3 or I have a singular set of ears. Mike Scott - AE6WA Tarzana, CA (DM04 / near LA) NAQCC 3535 K3-100 #508 / KX1 #1311 Unfortunately, the issue with the 12 kHz leakage (DAC clock?) and beat notes (+/- CW sidetone around 12 kHz) make for some awful audio in CW. I guess most folks don't hear it, but given previous reports from others, it is an issue. I can't comfortably use the K3 for CW unless using outboard low-pass audio filters to knock the high end garbage down to an in-audible level. 73 Eric NO3M -- View this message in context: http://n2.nabble.com/K3-Rev-C-DSP-with-Low-Freq-Enhancement-ship-date-info-New-swap-out-option-on-parts-order-page-tp3789876p3832365.html Sent from the [K3] mailing list archive at Nabble.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
Re: [Elecraft] [K3] K3 Rev C DSP with Low Freq Enhancement
Paul Christensen wrote: Take a look at what's happening before the ADC and after the DAC circuits. The K3 has some of the best designed audio circuits for a communications transceiver. Paul, W9AC Unfortunately, the issue with the 12 kHz leakage (DAC clock?) and beat notes (+/- CW sidetone around 12 kHz) make for some awful audio in CW. I guess most folks don't hear it, but given previous reports from others, it is an issue. I can't comfortably use the K3 for CW unless using outboard low-pass audio filters to knock the high end garbage down to an in-audible level. 73 Eric NO3M __ 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] K3 Rev C DSP with Low Freq Enhancement
Whatever happened to the filter being tested by Elecraft which was described in this post: http://marc.info/?l=elecraftm=124561590925425w=2 Bob NW8L On Tue, Oct 13, 2009 at 1:37 AM, Eric Tichansky n...@no3m.net wrote: Unfortunately, the issue with the 12 kHz leakage (DAC clock?) and beat notes (+/- CW sidetone around 12 kHz) make for some awful audio in CW. I guess most folks don't hear it, but given previous reports from others, it is an issue. I can't comfortably use the K3 for CW unless using outboard low-pass audio filters to knock the high end garbage down to an in-audible level. 73 Eric NO3M __ 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] K3 Rev C DSP with Low Freq Enhancement
P.B. Christensen wrote: I think what some folks are requesting is an updated schematic, showing the new values. But what they may not realize is that 7 SMT capacitors are changed -- or in the alternative, the corresponding SMT resistors require solder re-work and that's in addition to the C9/C13 change and so the total parts change may be in excess of 10. That's a lot of propensity for damage to the board and it really makes sense to just opt for the board swap through Elecraft. But since the capacitor values are all being increased, is it not an option simply to add conventional electrolytic capacitors in parallel to the SMT ones, as the photos on the Russian website appear to illustrate? That is something most people would be capable of doing, and could be especially attractive to those of us in Europe for whom the total cost of the board swap will amount to a lot more than $65. - Julian, G4ILO. K2 #392 K3 #222. * G4ILO's Shack - http://www.g4ilo.com * KComm - http://www.g4ilo.com/kcomm.html * KTune - http://www.g4ilo.com/ktune.html -- View this message in context: http://n2.nabble.com/K3-Rev-C-DSP-with-Low-Freq-Enhancement-ship-date-info-New-swap-out-option-on-parts-order-page-tp3789876p3802936.html Sent from the [K3] mailing list archive at Nabble.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
Re: [Elecraft] [K3] K3 Rev C DSP with Low Freq Enhancement
But since the capacitor values are all being increased, is it not an option simply to add conventional electrolytic capacitors in parallel to the SMT ones, as the photos on the Russian website appear to illustrate? I don't know what he has done, but it's possible to stack SMT capacitors if great care is taken. This will work for the line-in and mic-in changes, but I cannot see how stacking C9/C13 will work for the headphone output change. If he's accomplished that task, God bless him. Myself, I've found it takes a great balancing act to stack SMT parts and hold the new component in place. I'm not the world's best SMT re-work guy, so others may have developed better eye-hand coordination skills. Paul, W9AC __ 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] K3 Rev C DSP with Low Freq Enhancement
But since the capacitor values are all being increased, is it not an option simply to add conventional electrolytic capacitors in parallel to the SMT ones, as the photos on the Russian website appear to illustrate? The changes on the Russian web site are not official from Elecraft. Other than the changes to the headphone coupling capacitors, the changes on that web site involve mostly adding large electrolytic capacitors as additional bypassing and decoupling to supply lines or internal voltage references in amplifiers. Most of the changes are not related to audio response. 73, ... Joe, W4TV -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Julian, G4ILO Sent: Sunday, October 11, 2009 6:44 AM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] [K3] K3 Rev C DSP with Low Freq Enhancement P.B. Christensen wrote: I think what some folks are requesting is an updated schematic, showing the new values. But what they may not realize is that 7 SMT capacitors are changed -- or in the alternative, the corresponding SMT resistors require solder re-work and that's in addition to the C9/C13 change and so the total parts change may be in excess of 10. That's a lot of propensity for damage to the board and it really makes sense to just opt for the board swap through Elecraft. But since the capacitor values are all being increased, is it not an option simply to add conventional electrolytic capacitors in parallel to the SMT ones, as the photos on the Russian website appear to illustrate? That is something most people would be capable of doing, and could be especially attractive to those of us in Europe for whom the total cost of the board swap will amount to a lot more than $65. - Julian, G4ILO. K2 #392 K3 #222. * G4ILO's Shack - http://www.g4ilo.com * KComm - http://www.g4ilo.com/kcomm.html * KTune - http://www.g4ilo.com/ktune.html -- View this message in context: http://n2.nabble.com/K3-Rev-C-DSP-with-Low-Freq-Enhancement-sh ip-date-info-New-swap-out-option-on-parts-order-page-tp3789876p3802936.html Sent from the [K3] mailing list archive at Nabble.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 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] K3 Rev C DSP with Low Freq Enhancement ship date info; New swap out option on parts order page. CORRECTION
On Fri, 2009-10-09 at 13:37 -0700, Craig K3OOL wrote: Is the hardware mod to the DSP board required to see any effect from the f/w change in 3.41? That's primarily it. We increased coupling caps and a few other values in the audio chain to increase low freq audio response below 300 Hz. when combines with the latest f/w beta release it results in more low end below 300 Hz. I really wish we could get a full listing of the modifications that Elecraft is officially rolling into this DSP board revision. It doesn't even have to come with rework instructions and pictures... Just a list of value changes would have me pleased as punch. ~BTH __ 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] K3 Rev C DSP with Low Freq Enhancement ship date info; New swap out option on parts order page. CORRECTION
Brett Howard wrote: I really wish we could get a full listing of the modifications that Elecraft is officially rolling into this DSP board revision. It doesn't even have to come with rework instructions and pictures... Just a list of value changes would have me pleased as punch. This should be close but Elecraft has not updated their schematics since October 2008, so there could be differences: http://n1eu.com/K3/k3audiomod.htm 73, Bill -- View this message in context: http://n2.nabble.com/K3-Rev-C-DSP-with-Low-Freq-Enhancement-ship-date-info-New-swap-out-option-on-parts-order-page-tp3789876p3799423.html Sent from the [K3] mailing list archive at Nabble.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
Re: [Elecraft] [K3] K3 Rev C DSP with Low Freq Enhancement ship date info; New swap out option on parts order page. CORRECTION
This should be close but Elecraft has not updated their schematics since October 2008, so there could be differences: http://n1eu.com/K3/k3audiomod.htm Lyle and I exchanged notes on this a while back as he and I were experimenting with DSP Board component changes above and beyond the much-discussed headphone cap change. My guess is that the Rev. C board changes take the notes in the link into account. However, he was re-scaling R values. I had re-scaled C values since fewer components were involved in solder re-work. The net result is essentially the same but changing R values likely makes more sense in production where the cost of SMT resistors is essentially the same irrespective of component value versus the increased cost of higher-valued capacitors. And as Bill points out, there may be other subtle differences. Given the number of changes to the DSP Board, I recommend taking advantage of Elecraft's swap-out program unless there's a lot of comfort in SMT/SMD re-work. Paul, W9AC __ 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] K3 Rev C DSP with Low Freq Enhancement ship date info; New swap out option on parts order page. CORRECTION
I have a lot of confidence in SMT rework and I've done the C9 and C13 mod with exact replacement caps. I was told that changing those to 100uF was an official Elecraft mod so I went out and found the exact size replacement SMT caps and got them on there. They look like they were installed from the factory. I've got all the equipment to do SMT rework right down to removal and replacement of BGA components. If I just had an official list of modifications I'd just do it. Wonder if the replacement DSP board requires the return of our current one. My current one has traces cut for the low pass audio filter and what not... ~Brett On Sat, 2009-10-10 at 07:37 -0400, Paul Christensen wrote: This should be close but Elecraft has not updated their schematics since October 2008, so there could be differences: http://n1eu.com/K3/k3audiomod.htm Lyle and I exchanged notes on this a while back as he and I were experimenting with DSP Board component changes above and beyond the much-discussed headphone cap change. My guess is that the Rev. C board changes take the notes in the link into account. However, he was re-scaling R values. I had re-scaled C values since fewer components were involved in solder re-work. The net result is essentially the same but changing R values likely makes more sense in production where the cost of SMT resistors is essentially the same irrespective of component value versus the increased cost of higher-valued capacitors. And as Bill points out, there may be other subtle differences. Given the number of changes to the DSP Board, I recommend taking advantage of Elecraft's swap-out program unless there's a lot of comfort in SMT/SMD re-work. Paul, W9AC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] [K3] K3 Rev C DSP with Low Freq Enhancement ship date info; New swap out option on parts order page. CORRECTION
May I ask why the LF response improvement was confined to headphones only? Why was the improvement not applied to all audio outputs, or am I missing something here? Grateful thanks. DaveL G3TJP Lyle Johnson wrote: The hardware mods improve the *TX* audio path low frequency response from all three sources (front microphone, rear microphone, line in). They also improve the Rx low frequency response for *headphones* only. Lined out and speaker low frequency responses are not affected. 73, Lyle KK7P/7 (in Tucson, AZ) __ 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] K3 Rev C DSP with Low Freq Enhancement ship date info; New swap out option on parts order page. CORRECTION
May I ask why the LF response improvement was confined to headphones only? The speaker system has its own amplifier and already has excellent low frequency response. The headphones have their own amplifier and had 10 uF output caps, now changed to 100 uF. Line out also has its own amplifier and output network. Note that these are the electrical paths. The firmware LF improvement applies to *all* paths: headphones, speakers and line out. 73, Lyle KK7P/7 (Tucson AZ) __ 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] K3 Rev C DSP with Low Freq Enhancement ship date info; New swap out option on parts order page. CORRECTION
KK7P wrote: May I ask why the LF response improvement was confined to headphones only? The speaker system has its own amplifier and already has excellent low frequency response. The headphones have their own amplifier and had 10 uF output caps, now changed to 100 uF. Line out also has its own amplifier and output network. Note that these are the electrical paths. The firmware LF improvement applies to *all* paths: headphones, speakers and line out. Is there any difference between the official modifications and this one: http://ur5lam.jimdo.com/elecraft-k3-mod-s-page/ ? I find it a bit difficult to see exactly what the unofficial mods are as it isn't entirely clear what components / boards are affected from the photographs. I can't really justify the cost of replacing the DSP board given that I don't think there is much wrong with the K3 audio at the moment. But I have a big bag of assorted electrolytic capacitors sitting in my junk box. - Julian, G4ILO. K2 #392 K3 #222. * G4ILO's Shack - http://www.g4ilo.com * KComm - http://www.g4ilo.com/kcomm.html * KTune - http://www.g4ilo.com/ktune.html -- View this message in context: http://n2.nabble.com/K3-Rev-C-DSP-with-Low-Freq-Enhancement-ship-date-info-New-swap-out-option-on-parts-order-page-tp3789876p3801447.html Sent from the [K3] mailing list archive at Nabble.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
Re: [Elecraft] [K3] K3 Rev C DSP with Low Freq Enhancement shipdate info; New swap out option on parts order page. CORRECTION
Why was the improvement not applied to all audio outputs, or am I missing something here? When you go through the schematic and run the response calculations, those were the only changes necessary to improve low-end response for all Rx and Tx paths. Take a look at what's happening before the ADC and after the DAC circuits. The K3 has some of the best designed audio circuits for a communications transceiver. Paul, W9AC __ 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] K3 Rev C DSP with Low Freq Enhancement shipdateinfo; New swap out option on parts order page. CORRECTION
Paul This is so confusing. First, a hardware change (2 caps) improves bass then along comes a firmware change that does the same thing but only for headphones and line out and then a new DSP board that works with the firmware to do the same thing but still only for headphones and line out and now we're back to the 2 caps that improve headphone, line and speaker audio. No wonder there are so many questions. I wish someone would make this more clear. Steve N4LQ n...@carolina.rr.com - Original Message - From: Paul Christensen w...@arrl.net To: elecraft@mailman.qth.net Sent: Saturday, October 10, 2009 7:54 PM Subject: Re: [Elecraft] [K3] K3 Rev C DSP with Low Freq Enhancement shipdateinfo; New swap out option on parts order page. CORRECTION Why was the improvement not applied to all audio outputs, or am I missing something here? When you go through the schematic and run the response calculations, those were the only changes necessary to improve low-end response for all Rx and Tx paths. Take a look at what's happening before the ADC and after the DAC circuits. The K3 has some of the best designed audio circuits for a communications transceiver. Paul, W9AC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] [K3] K3 Rev C DSP with Low Freq Enhancement shipdateinfo; New swap out option on parts order page. CORRECTION
Steve, Hopefully I can make it more clear. The speaker and line out audio *already* had sufficient low response with no changes. The headphone output had limitations unless higher impedance headphones were used. The capacitor changes allowed lower frequency response with lower impedance headphones. As for the firmware, previously, the bass response was limited in the firmware. That limitation has now been relaxed and greater low frequency content can be heard in the speaker (assuming you have a speaker that can produce those lows, the internal speaker is not that speaker), or at line out. If you are using low impedance headphones, you will need to increase the capacitors to hear the difference in the headphone output. 73, Don W3FPR Steve Ellington wrote: Paul This is so confusing. First, a hardware change (2 caps) improves bass then along comes a firmware change that does the same thing but only for headphones and line out and then a new DSP board that works with the firmware to do the same thing but still only for headphones and line out and now we're back to the 2 caps that improve headphone, line and speaker audio. No wonder there are so many questions. I wish someone would make this more clear. Steve N4LQ n...@carolina.rr.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
Re: [Elecraft] [K3] K3 Rev C DSP with Low Freq Enhancement
Let me try and eliminate the confusion. 1) The low frequency response is constrained by two things: the audio path components, and the various filters (roofing filter, DSP IF filter and DSP audio filter (including Rx Equalizer). 2) Several months ago, there were circuit component changes made to the DSP board to improve Tx and Rx low frequency response. The Rx path that was changed was the headphone path -- 10 yF output capacitors were changed to 100 uF capacitors. There was no need to change components in the speaker or Line Out circuitry. 3) At the time these capacitors were changed, *other* component changes were made to improve the *transmit* audio low frequency response. Several components were changed to improve this response for the front panel microphone, rear panel microphone, and line input paths. 4) With these changes, the receive low frequency response was now limited by the various filters (roofing filter, DSP IF filter and DSP audio filter). 5) The firmware in the K3 sets up the filters for maximum communications effectiveness, making the nominal low frequency roll-off around 200 Hz. 6) The latest beta test firmware *allows* you to move the combined *filter* response lower, improving low frequency fidelity if you so desire. This will affect all the possible receive paths: speaker, headphones and line out. 73, Lyle KK7P/7 (vacationing in Tucson AZ) __ 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] K3 Rev C DSP with Low Freq Enhancement
3) At the time these capacitors were changed, *other* component changes were made to improve the *transmit* audio low frequency response. Several components were changed to improve this response for the front panel microphone, rear panel microphone, and line input paths. Lyle, As I recall, the *other* changes affect both line-in and mic-in. On the N1EU website, I've documented those changes with only C value changes instead of R value changes. I think what some folks are requesting is an updated schematic, showing the new values. But what they may not realize is that 7 SMT capacitors are changed -- or in the alternative, the corresponding SMT resistors require solder re-work and that's in addition to the C9/C13 change and so the total parts change may be in excess of 10. That's a lot of propensity for damage to the board and it really makes sense to just opt for the board swap through Elecraft. Paul, W9AC __ 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] K3 Rev C DSP with Low Freq Enhancement
I think what some folks are requesting is an updated schematic... Approximately every October I gather the latest schematics and integrate them into a PDF document which we post on the website. The original schematic set was Oct 2007, the present set is Oct 2008. When I return from vacation, I'll be gathering the information again for a new schematic release in October or November. 73, Lyle KK7P/7 (Tucson AZ) __ 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] K3 Rev C DSP with Low Freq Enhancement
Is there any chance of a list of changes that aren't published as mods? On Sat, 2009-10-10 at 22:15 -0700, lyle johnson wrote: I think what some folks are requesting is an updated schematic... Approximately every October I gather the latest schematics and integrate them into a PDF document which we post on the website. The original schematic set was Oct 2007, the present set is Oct 2008. When I return from vacation, I'll be gathering the information again for a new schematic release in October or November. 73, Lyle KK7P/7 (Tucson AZ) __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] [K3] K3 Rev C DSP with Low Freq Enhancement
Bruce Beford-2 wrote: Eric, Would it be possible to release an app note listing the component value changes you mention: We increased coupling caps and a few other values in the audio chain to increase low freq audio response below 300 Hz. This way, those of us who feel up to the task can modify our own early DSP boards. I assume the changes are similar to, or an extension of what has been published privately by Paul and Ed. It would be very nice to see the official changes. It would also be interesting to compare this with the unofficial mods posted on a Russian site that have been mentioned a couple of times recently. Personally I am quite happy with the sound of my K3 as it is now with the latest firmware. But reading about these mods make me wonder whether I am really missing out on something. - Julian, G4ILO. K2 #392 K3 #222. * G4ILO's Shack - http://www.g4ilo.com * KComm - http://www.g4ilo.com/kcomm.html * KTune - http://www.g4ilo.com/ktune.html -- View this message in context: http://n2.nabble.com/Re-K3-Rev-C-DSP-with-Low-Freq-Enhancement-tp3791204p3793366.html Sent from the [K3] mailing list archive at Nabble.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
Re: [Elecraft] [K3] K3 Rev C DSP with Low Freq Enhancement ship date info; New swap out option on parts order page. CORRECTION
Is the hardware mod to the DSP board required to see any effect from the f/w change in 3.41? That's primarily it. We increased coupling caps and a few other values in the audio chain to increase low freq audio response below 300 Hz. when combines with the latest f/w beta release it results in more low end below 300 Hz. -- View this message in context: http://n2.nabble.com/K3-Rev-C-DSP-with-Low-Freq-Enhancement-ship-date-info-New-swap-out-option-on-parts-order-page-tp3789876p3797140.html Sent from the [K3] mailing list archive at Nabble.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
Re: [Elecraft] [K3] K3 Rev C DSP with Low Freq Enhancement ship date info; New swap out option on parts order page. CORRECTION
Is the hardware mod to the DSP board required to see any effect from the f/w change in 3.41? No. The hardware mods improve the *TX* audio path low frequency response from all three sources (front microphone, rear microphone, line in). They also improve the Rx low frequency response for *headphones* only. Lined out and speaker low frequency responses are not affected. 73, Lyle KK7P/7 (in Tucson, AZ) __ 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
