Re: [Elecraft] K3 Filter question
Hi Keith, In the K3 utility program, you can change the filter bandwidths to whatever you need. Many ops use this function to set filter switch points that are different than the listed bandwidth. Look under the Configure tab, then push the Configure Crystal Filters radio button. Note that setting a non-standard filter bandwidth only changes the point at which changing the Width (or Hi/Lo) control causes a switch to the next filter in your stack. Actual filter performance stays as it is. Just a normal disclaimer... :) 73, matt W6NIA On Wed, 26 Feb 2014 06:28:59 -0800, you wrote: I have recently been examining how my K3 filters operate and was curious if I could somehow expand the range I can use my lowest filter which is 250 kHz. It generally cuts out at 300 kHz and then my 1.8 kHz filter takes over. I would like to use the 250 kHz filter up to 400 kHz as I have read the filter is actually specified for 370 kHz. How do i change the cut out point for this filter? Is this something I can change in the utility program under filter calibration? I appreciate any advice on this. Thanks, Keith AK6ZZ Sent from my iPhone please excuse typos __ 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 Matt Zilmer, W6NIA -- Give me six hours to chop down a tree and I will spend the first four sharpening the axe. -A. Lincoln __ 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 Filter question
How do i change the cut out point for this filter? Is this something I can change in the utility program under filter calibration? Yes, set the bandwidth of that slot to 380 or 400 Hz. See the Owner's Manual or K3 Utility help file. 73, ... Joe, W4TV On 2/26/2014 9:28 AM, Keith Heimbold wrote: I have recently been examining how my K3 filters operate and was curious if I could somehow expand the range I can use my lowest filter which is 250 kHz. It generally cuts out at 300 kHz and then my 1.8 kHz filter takes over. I would like to use the 250 kHz filter up to 400 kHz as I have read the filter is actually specified for 370 kHz. How do i change the cut out point for this filter? Is this something I can change in the utility program under filter calibration? I appreciate any advice on this. Thanks, Keith AK6ZZ Sent from my iPhone please excuse typos __ 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 Filter question
Matt, Thanks, I was hoping that was the case. The 1.8 kHz filter is good for SSB but not exactly what I want at 350 kHz in CW. I think I will set it for 600 kHz and see what happens. I really appreciate your quick response. Keith AK6ZZ Sent from my iPhone please excuse typos On Feb 26, 2014, at 6:38 AM, Matt Zilmer mzil...@roadrunner.com wrote: Hi Keith, In the K3 utility program, you can change the filter bandwidths to whatever you need. Many ops use this function to set filter switch points that are different than the listed bandwidth. Look under the Configure tab, then push the Configure Crystal Filters radio button. Note that setting a non-standard filter bandwidth only changes the point at which changing the Width (or Hi/Lo) control causes a switch to the next filter in your stack. Actual filter performance stays as it is. Just a normal disclaimer... :) 73, matt W6NIA On Wed, 26 Feb 2014 06:28:59 -0800, you wrote: I have recently been examining how my K3 filters operate and was curious if I could somehow expand the range I can use my lowest filter which is 250 kHz. It generally cuts out at 300 kHz and then my 1.8 kHz filter takes over. I would like to use the 250 kHz filter up to 400 kHz as I have read the filter is actually specified for 370 kHz. How do i change the cut out point for this filter? Is this something I can change in the utility program under filter calibration? I appreciate any advice on this. Thanks, Keith AK6ZZ Sent from my iPhone please excuse typos __ 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 Matt Zilmer, W6NIA -- Give me six hours to chop down a tree and I will spend the first four sharpening the axe. -A. Lincoln __ 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 Filter question
Thanks Joe for additional clarification will set to 400 kHz. 73, Keith AK6ZZ Sent from my iPhone please excuse typos On Feb 26, 2014, at 6:45 AM, Joe Subich, W4TV li...@subich.com wrote: How do i change the cut out point for this filter? Is this something I can change in the utility program under filter calibration? Yes, set the bandwidth of that slot to 380 or 400 Hz. See the Owner's Manual or K3 Utility help file. 73, ... Joe, W4TV On 2/26/2014 9:28 AM, Keith Heimbold wrote: I have recently been examining how my K3 filters operate and was curious if I could somehow expand the range I can use my lowest filter which is 250 kHz. It generally cuts out at 300 kHz and then my 1.8 kHz filter takes over. I would like to use the 250 kHz filter up to 400 kHz as I have read the filter is actually specified for 370 kHz. How do i change the cut out point for this filter? Is this something I can change in the utility program under filter calibration? I appreciate any advice on this. Thanks, Keith AK6ZZ Sent from my iPhone please excuse typos __ 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 __ 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 Filter question
Hi Keith, I understand, and I'm running the 250 Hz filters in main and sub receivers at 350 Hz, myself. If you make this type of adjustment, you might want to check the amount of gain for the filter with the changed switch point. It shouldn't be off by much, but worth checking anyway. 73, matt W6NIA On Wed, 26 Feb 2014 06:45:53 -0800, you wrote: Matt, Thanks, I was hoping that was the case. The 1.8 kHz filter is good for SSB but not exactly what I want at 350 kHz in CW. I think I will set it for 600 kHz and see what happens. I really appreciate your quick response. Keith AK6ZZ Sent from my iPhone please excuse typos On Feb 26, 2014, at 6:38 AM, Matt Zilmer mzil...@roadrunner.com wrote: Hi Keith, In the K3 utility program, you can change the filter bandwidths to whatever you need. Many ops use this function to set filter switch points that are different than the listed bandwidth. Look under the Configure tab, then push the Configure Crystal Filters radio button. Note that setting a non-standard filter bandwidth only changes the point at which changing the Width (or Hi/Lo) control causes a switch to the next filter in your stack. Actual filter performance stays as it is. Just a normal disclaimer... :) 73, matt W6NIA On Wed, 26 Feb 2014 06:28:59 -0800, you wrote: I have recently been examining how my K3 filters operate and was curious if I could somehow expand the range I can use my lowest filter which is 250 kHz. It generally cuts out at 300 kHz and then my 1.8 kHz filter takes over. I would like to use the 250 kHz filter up to 400 kHz as I have read the filter is actually specified for 370 kHz. How do i change the cut out point for this filter? Is this something I can change in the utility program under filter calibration? I appreciate any advice on this. Thanks, Keith AK6ZZ Sent from my iPhone please excuse typos __ 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 Matt Zilmer, W6NIA -- Give me six hours to chop down a tree and I will spend the first four sharpening the axe. -A. Lincoln Matt Zilmer, W6NIA -- Give me six hours to chop down a tree and I will spend the first four sharpening the axe. -A. Lincoln __ 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 Filter question. Again?
Phil, Go to this link on the Elecraft website: http://www.elecraft.com/K3/Roofing_Filters.htm And this link: http://www.elecraft.com/K3/K3_filter_plots.htm Dave, N4QS - Original Message - From: Phil Townsend phi...@mac.com Cc: elecraft@mailman.qth.net Sent: Wednesday, August 08, 2012 8:12 PM Subject: [Elecraft] K3 Filter question. Again? Why an 8 pole filter OR Why a 5 pole filter? Yeah I know the 5 poles are cheaper... but other than that. Phil Santa Fe __ 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 Filter question Again?
Those 8-pole filters have steeper skirts. Either the 5- or 8-pole work quite well. I use 5-pole for the narrower filters (250, 500), and the 8-pole for 1.8, 2.8, 13 KHz bandwidths. 73, matt W6NIA K3 #24 On Wed, 08 Aug 2012 19:12:58 -0600, you wrote: Why an 8 pole filter OR Why a 5 pole filter? Yeah I know the 5 poles are cheaper... but other than that. Phil Santa Fe __ 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 Filter question Again?
My thought on the 5 pole was that it would give you some protection but because the skirts were not as steep you could hear someone calling you off frequency better. They would be down but not out. The 5's have slightly less insertion loss and are cheaper. On the other hand they need an offset adjustment and therefore don't lend themselves to diversity reception as well. I think the answer is: it depends on your style of operating and what you want to spend. The reason there is more than one choice is that one size does not fit all. Or, as my Nana used to say, that's why they don't make it all vanilla. Sent from my iPad On Aug 8, 2012, at 10:04 PM, Matt Zilmer mzil...@verizon.net wrote: Those 8-pole filters have steeper skirts. Either the 5- or 8-pole work quite well. I use 5-pole for the narrower filters (250, 500), and the 8-pole for 1.8, 2.8, 13 KHz bandwidths. 73, matt W6NIA K3 #24 On Wed, 08 Aug 2012 19:12:58 -0600, you wrote: Why an 8 pole filter OR Why a 5 pole filter? Yeah I know the 5 poles are cheaper... but other than that. Phil Santa Fe __ 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 __ 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 Filter question Again?
Good point. It would depend upon whether or not you'd want to hear someone so far from zero beat. 73, matt On Wed, 08 Aug 2012 23:38:06 -0400, you wrote: My thought on the 5 pole was that it would give you some protection but because the skirts were not as steep you could hear someone calling you off frequency better. They would be down but not out. The 5's have slightly less insertion loss and are cheaper. On the other hand they need an offset adjustment and therefore don't lend themselves to diversity reception as well. I think the answer is: it depends on your style of operating and what you want to spend. The reason there is more than one choice is that one size does not fit all. Or, as my Nana used to say, that's why they don't make it all vanilla. Sent from my iPad On Aug 8, 2012, at 10:04 PM, Matt Zilmer mzil...@verizon.net wrote: Those 8-pole filters have steeper skirts. Either the 5- or 8-pole work quite well. I use 5-pole for the narrower filters (250, 500), and the 8-pole for 1.8, 2.8, 13 KHz bandwidths. 73, matt W6NIA K3 #24 On Wed, 08 Aug 2012 19:12:58 -0600, you wrote: Why an 8 pole filter OR Why a 5 pole filter? Yeah I know the 5 poles are cheaper... but other than that. Phil Santa Fe __ 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 __ 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 Filter question - SSB
Down at WP2Z for CQWW SSB Test we sometimes on 20M opened up the bandwidth to 2.4KHZ. Even with strong adjacent signals (as always the case on 20M) we could keep our run rate higher than with narrower bandwidth. It was just easier to copy calls even with all that adjacent QRM. 73, N2TK, Tony -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Bill W4ZV Sent: Thursday, November 10, 2011 2:21 PM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 Filter question - SSB Barry N1EU wrote: Bill W4ZV wrote: 1. It *WILL* keep your AGC from pumping if there's another strong station within the 1.8 kHz passband. However, do you really think you could copy a weak signal while a S9+30 interfering signal is inside your 1.8k bandwidth? I don't think so. With any typical SSB filter bandwidth, AGC pumping is not a practical issue (it IS a big deal for CW however). Bill, I'm confused by that first sentence. How can a signal within the passband NOT pump the AGC? Normally when AGC pumping is discussed, it's a negative reference to an adjacent signal that's outside of the passband. Barry N1EU You're correct Barry. I meant to say just outside your passband. However, given that most SSB signals generate 3rd garbage (spurs, phase noise, etc) in the area of -35 dBc, an S9+30 signal just outside your 1.8k passband will easily obliterate a weak signal inside the passband. I found my ears to be the best tool for copying weak signals in the presence of strong adjacent splatter. For whatever reason they heard better using the stock 5-pole 2.7k set to a DSP BW of 2.0-2.1k than the 8-pole 1.8k set to actuate at DSP = 1.9k. I tried many times to use the 1.8k but simply just found the 2.7k worked better for me. Of course that's just my experience which wouldn't necessarily apply to everyone. 73, Bill -- View this message in context: http://elecraft.365791.n2.nabble.com/K3-Filter-question-SSB-tp6981339p698291 2.html Sent from the Elecraft 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 Filter question - SSB
Ian White GM3SEK wrote: Unlike a 1.8kHz DSP filter with a 2.5kHz roofing filter, the 1.8kHz crystal filter also avoids artefacts caused by pumping of the hardware AGC loop by strong signals in the gaps between the wider and the narrower passband. The suggestion is that a 1.8Khz roofing filter will avoid HAGC pumping if the shoulder of an s9+25dB signal is present in the 350hz gap (2500-1800/2) that would have been spanned by the 2.5Khz filter. This is true but I'd suggest that if the s9+25dB shoulder is within 350hz, there's going to be plenty of that adjacent signal spilling over into your dsp passband that's going to pump your dsp AGC. So at best you will get slight improvement with the narrower filter but I wonder if it would ever make a difference in copy ability. A narrow filter just isn't buying you that much in ssb. Barry N1EU -- View this message in context: http://elecraft.365791.n2.nabble.com/K3-Filter-question-SSB-tp6981339p6984984.html Sent from the Elecraft 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 Filter question - SSB
Go the 1.8KHz filter bruce, Forget the 2.1. 73 de Jeff Cochrane - VK4BOF East Innisfail QLD, Australia K3 #4257, P3#1629, KPA-500 #161 - Original Message - From: Bruce Meier To: elecraft@mailman.qth.net Sent: Thursday, November 10, 2011 9:29 PM Subject: [Elecraft] K3 Filter question - SSB As I operate much more CW than SSB I need some advice and opinions from the SSB contesters before adding additional filters for my K3s. Currently I only have the stock 2.7Khz filters in both K3s (main and sub rx) for SSB. I have 400hz and 250hz for CW. If I wanted to add an additional roofing filter for SSB contesting, would I add a 1.8Khz or would I add the 2.1Khz. 73, Bruce - N1LN __ 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 Filter question - SSB
Bruce this is from a similar question on the Yahoo Groups K3 list: -- In elecraft...@yahoogroups.com, Hector Padron ad4c2006@... wrote: The 1.8 roofer today with so much band noise and fool ops close to your freq disrespecting the spectrum, its a must.This 8 poles filter together with the DSP makes brick rx easy to work dx or contesting.The trick to recover the lost audio quality when using it is to move counterclockwise the shift control down to 1.2 and inteligibility is back. This is very misleading and I must strongly disagree. I preface this by saying I made ~2500 QSOs on 10m single band in the CQ WW (high-claimed USA SOSB/10 score) and was never able to effectively use the 1.8k filter even though I tried in vain several times. Here's what a 1.8k will and will not do: 1. It *WILL* keep your AGC from pumping if there's another strong station within the 1.8 kHz passband. However, do you really think you could copy a weak signal while a S9+30 interfering signal is inside your 1.8k bandwidth? I don't think so. With any typical SSB filter bandwidth, AGC pumping is not a practical issue (it IS a big deal for CW however). 2. It *WILL *NOT* keep splatter from adjacent signals out of your passband. If an interfering signal is 5 kHz wide and partially falls within your passband, NO filter can remove it. Splatter is a real signal which NO filter (XTAL or DSP) can remove. 3. It *WILL* require very careful tuning for intelligibility. With callers that are off frequency by only 100 Hz, you'll miss off-frequency callers the first time which will slow your run rate. I had one caller even 500 Hz below my run frequency and I'm certain I would never have heard him if I was using the 1.8k. The most effective use of a 1.8k is probably for copying an extremely weak DX signal in white noise (not strong splatter or QRM). By tuning VERY carefully, you may slightly reduce the noise floor by reducing the noise bandwidth (potential reduction of 1.8k BW versus 2.1k BW is 10*[log (1.8/2.1)] = -0.67 dB). I really doubt many of us can detect a 0.67 dB improvement in signal/noise. The 1.8k is mainly a DXing tool...not a contesting tool. It cannot magically overcome the basic laws of physics. 73, Bill W4ZV -- View this message in context: http://elecraft.365791.n2.nabble.com/K3-Filter-question-SSB-tp6981339p6981505.html Sent from the Elecraft 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 Filter question - SSB
Bill W4ZV wrote: 3. It *WILL* require very careful tuning for intelligibility. With callers that are off frequency by only 100 Hz, you'll miss off-frequency callers the first time which will slow your run rate. I had one caller even 500 Hz below my run frequency and I'm certain I would never have heard him if I was using the 1.8k. Just to qualify what I mean by high run rates: -- Q S O R a t e S u m m a r y - Hour 160 80 40 20 15 10Rate TotalPct 1200 0 0 0 0 01731732269.1 1300 0 0 0 0 0186186412 16.6 1400 0 0 0 0 0200200612 24.6 1500 0 0 0 0 0163163775 31.2 1600 0 0 0 0 0112112887 35.7 1200 0 0 0 0 0128128 1481 59.6 1300 0 0 0 0 0155155 1636 65.8 1400 0 0 0 0 0144144 1780 71.6 1500 0 0 0 0 0163163 1943 78.2 1600 0 0 0 0 0128128 2071 83.3 1700 0 0 0 0 0138138 2209 88.9 The best 60 minute rate was 217/hour from 1349 to 1448 The best 30 minute rate was 228/hour from 1358 to 1427 The best 10 minute rate was 246/hour from 1418 to 1427 The best 1 minute rates were: 6 QSOs/minute7 times. 5 QSOs/minute 32 times. 4 QSOs/minute 122 times. 3 QSOs/minute 238 times. 2 QSOs/minute 328 times. 1 QSOs/minute 425 times. The 1.8k is a nice tool when working a weak DX station who is running the pileup. It is very poor if you're the one who is running and attempting to work callers at high rates (i.e. getting the call correctly the first time without repeats). I'll be selling my 1.8k in favor of a 2.1k after my recent experience. 73, Bill -- View this message in context: http://elecraft.365791.n2.nabble.com/K3-Filter-question-SSB-tp6981339p6981677.html Sent from the Elecraft 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 Filter question - SSB
The 1.8 is where I would go. Inrad also sells a 1.5 which a number of people swear by for really nasty SSB contests. Mike W0MU J6M CQ WW DX CW Contest 2011 J6/W0MU November 21 - December 1 2011 W0MU-1 CC Cluster w0mu.net On 11/10/2011 4:29 AM, Bruce Meier wrote: As I operate much more CW than SSB I need some advice and opinions from the SSB contesters before adding additional filters for my K3s. Currently I only have the stock 2.7Khz filters in both K3s (main and sub rx) for SSB. I have 400hz and 250hz for CW. If I wanted to add an additional roofing filter for SSB contesting, would I add a 1.8Khz or would I add the 2.1Khz. 73, Bruce - N1LN __ 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 Filter question - SSB
I would not go any tighter than 1.8 KHz. I have a pair of the 1.5 KHz filters that I would swap for 1.8s. 73, ... Joe, W4TV On 11/10/2011 10:11 AM, W0MU Mike Fatchett wrote: The 1.8 is where I would go. Inrad also sells a 1.5 which a number of people swear by for really nasty SSB contests. Mike W0MU J6M CQ WW DX CW Contest 2011 J6/W0MU November 21 - December 1 2011 W0MU-1 CC Cluster w0mu.net On 11/10/2011 4:29 AM, Bruce Meier wrote: As I operate much more CW than SSB I need some advice and opinions from the SSB contesters before adding additional filters for my K3s. Currently I only have the stock 2.7Khz filters in both K3s (main and sub rx) for SSB. I have 400hz and 250hz for CW. If I wanted to add an additional roofing filter for SSB contesting, would I add a 1.8Khz or would I add the 2.1Khz. 73, Bruce - N1LN __ 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 Filter question - SSB
Bill W4ZV wrote: 1. It *WILL* keep your AGC from pumping if there's another strong station within the 1.8 kHz passband. However, do you really think you could copy a weak signal while a S9+30 interfering signal is inside your 1.8k bandwidth? I don't think so. With any typical SSB filter bandwidth, AGC pumping is not a practical issue (it IS a big deal for CW however). Bill, I'm confused by that first sentence. How can a signal within the passband NOT pump the AGC? Normally when AGC pumping is discussed, it's a negative reference to an adjacent signal that's outside of the passband. Barry N1EU -- View this message in context: http://elecraft.365791.n2.nabble.com/K3-Filter-question-SSB-tp6981339p6982046.html Sent from the Elecraft 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 Filter question - SSB
I also have a pair of the 1.5 KHz filters, and while I find them to be desirable under certain DXing situations, I rarely use them in a contest. In a contest you need quick intelligibility and filters as narrow as 1.5 KHz don't necessarily give you that. I have a pretty good ear, but lots of human voices have enough energy in different parts of the audio spectrum that I find it sometimes necessary to either shift to a wider filter or change the shift on the 1.5 KHz filter (I typically use 1.1 KHz for the center with that filter) in order to copy the other guy's callsign or exchange. Plus, as W4ZV pointed out, there is so much atrocious splatter from crummy rigs or ignorantly adjusted rigs during a major contest that it is truly rare to find such a narrow filter actually being helpful. I also would trade my 1.5 KHz filters for a pair of 1.8 KHz filters in a heartbeat. 73, Dave AB7E On 11/10/2011 8:27 AM, Joe Subich, W4TV wrote: I would not go any tighter than 1.8 KHz. I have a pair of the 1.5 KHz filters that I would swap for 1.8s. 73, ... Joe, W4TV On 11/10/2011 10:11 AM, W0MU Mike Fatchett wrote: The 1.8 is where I would go. Inrad also sells a 1.5 which a number of people swear by for really nasty SSB contests. Mike W0MU J6M CQ WW DX CW Contest 2011 J6/W0MU November 21 - December 1 2011 W0MU-1 CC Cluster w0mu.net On 11/10/2011 4:29 AM, Bruce Meier wrote: As I operate much more CW than SSB I need some advice and opinions from the SSB contesters before adding additional filters for my K3s. Currently I only have the stock 2.7Khz filters in both K3s (main and sub rx) for SSB. I have 400hz and 250hz for CW. If I wanted to add an additional roofing filter for SSB contesting, would I add a 1.8Khz or would I add the 2.1Khz. 73, Bruce - N1LN __ 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 Filter question - SSB
On 11/10/2011 8:34 AM, David Gilbert wrote: there is so much atrocious splatter from crummy rigs or ignorantly adjusted rigs during a major contest YES, YES, YES. that it is truly rare to find such a narrow filter actually being helpful. I also would trade my 1.5 KHz filters for a pair of 1.8 KHz filters in a heartbeat. I strongly agree. I have 1.8 kHz filters in my K3s, and find that I rarely use them during a contest for the reasons that W4ZV has articulated. Paraphrasing from another world, it's the TRASH, stupid! 73, Jim K9YC __ 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 Filter question - SSB
Barry N1EU wrote: Bill W4ZV wrote: 1. It *WILL* keep your AGC from pumping if there's another strong station within the 1.8 kHz passband. However, do you really think you could copy a weak signal while a S9+30 interfering signal is inside your 1.8k bandwidth? I don't think so. With any typical SSB filter bandwidth, AGC pumping is not a practical issue (it IS a big deal for CW however). Bill, I'm confused by that first sentence. How can a signal within the passband NOT pump the AGC? Normally when AGC pumping is discussed, it's a negative reference to an adjacent signal that's outside of the passband. Barry N1EU You're correct Barry. I meant to say just outside your passband. However, given that most SSB signals generate 3rd garbage (spurs, phase noise, etc) in the area of -35 dBc, an S9+30 signal just outside your 1.8k passband will easily obliterate a weak signal inside the passband. I found my ears to be the best tool for copying weak signals in the presence of strong adjacent splatter. For whatever reason they heard better using the stock 5-pole 2.7k set to a DSP BW of 2.0-2.1k than the 8-pole 1.8k set to actuate at DSP = 1.9k. I tried many times to use the 1.8k but simply just found the 2.7k worked better for me. Of course that's just my experience which wouldn't necessarily apply to everyone. 73, Bill -- View this message in context: http://elecraft.365791.n2.nabble.com/K3-Filter-question-SSB-tp6981339p6982912.html Sent from the Elecraft 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 Filter question - SSB
I've had exactly the same experience. If the offending QRM is outside the passband of the filter, the narrower filter setting helps. However, If the offending QRM is heavily inside the passband (i.e., splatter), it seems that the additional intelligibility gain by capturing more of the desired station's audio bandwidth can often more than offset the additional interference you get from using a wider bandwidth. A lot depends upon the desired station's voice characteristics, but I've played with this quite a bit and the results can be surprising. Splatter is the enemy of us all, except of course for the idiots who do it intentionally to give themselves elbow room. One of these days I'm going to start posting spectral screenshots of significant offenders on my web site. 73, Dave AB7E On 11/10/2011 12:21 PM, Bill W4ZV wrote: I found my ears to be the best tool for copying weak signals in the presence of strong adjacent splatter. For whatever reason they heard better using the stock 5-pole 2.7k set to a DSP BW of 2.0-2.1k than the 8-pole 1.8k set to actuate at DSP = 1.9k. I tried many times to use the 1.8k but simply just found the 2.7k worked better for me. Of course that's just my experience which wouldn't necessarily apply to everyone. 73, Bill __ 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 Filter question - SSB
Bill W4ZV wrote: However, given that most SSB signals generate 3rd garbage (spurs, phase noise, etc) in the area of -35 dBc, an S9+30 signal just outside your 1.8k passband will easily obliterate a weak signal inside the passband. I agree. Although I routinely use 1.8Khz roofing filters in ssb contests, I doubt they help at all and are probably a waste of money. What does help to copy a weaker signal in the presence of splatter is to turn AGC off. Barry N1EU -- View this message in context: http://elecraft.365791.n2.nabble.com/K3-Filter-question-SSB-tp6981339p6983028.html Sent from the Elecraft 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 Filter question - SSB
happens outside of contests as well I can get alongside of a SSB signal and if it is clean have no problem but the guys that feel increasing there bandwidth for a better/pleasant sounding signal creep me out,,, the K3 is the first rcv I can say this about if the signal next door is clean regardless of strength it causes no problems looking forward to the KX3 Bob K3DJC On Thu, 10 Nov 2011 10:58:46 -0800 Jim Brown j...@audiosystemsgroup.com writes: On 11/10/2011 8:34 AM, David Gilbert wrote: there is so much atrocious splatter from crummy rigs or ignorantly adjusted rigs during a major contest YES, YES, YES. that it is truly rare to find such a narrow filter actually being helpful. I also would trade my 1.5 KHz filters for a pair of 1.8 KHz filters in a heartbeat. I strongly agree. I have 1.8 kHz filters in my K3s, and find that I rarely use them during a contest for the reasons that W4ZV has articulated. Paraphrasing from another world, it's the TRASH, stupid! 73, Jim K9YC __ 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 America#39;s #1 Skin Cream Cure Wrinkles Immediately for Just $5 http://thirdpartyoffers.juno.com/TGL3141/4ebc2c4258d6875f0bm03vuc __ 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 Filter question - SSB
I'm glad this came up because it is an aspect of filtering that seldom is addressed. Many folks seem to think that you can arbitrarily close down the bandwidth of a receiver to eliminate QRM and improve intelligibility. 1.8 kHz is deemed better than 2.1 kHz, and 1.5 kHz is deemed better than both. But at some point intelligibility itself suffers because you start to eliminate the signal you're trying to copy in the first place. I for one suffer from a type of listener's fatigue when forced to copy SSB signals in anything less than about 2.2 kHz or so. Others folks suffer from hearing loss and need to hear as much of the voice frequencies as possible. 1.8 kHz just doesn't work for many of these folks. If you're okay with such narrow bandwidths, more power to you, but you can't make blanket statements about them being equally effective for everybody. As Bill, Dave, and Barry alluded to, the ear-brain filter is the most effective of all, and it would do us all good to exercise it more often. The more you use it, the better you get at it. Bill W4ZV wrote: 3. It *WILL* require very careful tuning for intelligibility. __ 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 Filter question - SSB
Interesting to me is position today that 2.1 kHz is narrow. For many decades, a 2.1 kHz filter was normal, and sometimes only SSB filter. Heathkit SB-101 etc 350 - 2450 (center 1400) Collins KWM-2A etc 400 - 2500 (center 1450) Sometime during the 90s, or so, the standard seemed to move to 2.4 kHz and up. What happened? Because of my early experiences with a SB-101, I decided that the Heath SSB BW settings were for me. Therefore I have a 2.1 kHz roofing filter installed and set the BW to 350 - 2450 and stored into NORM1. Which leads into a K3 issue. I believe that it would be a service to all of us users if the K3 manual had a set of optimal center frequencies for some of the pseudo standard settings optimized by those before us at Heathkit, Collins, and others. And it would be nice if the NORM button was programmable. I understand that there are the NORM1 and NORM2 settings, but for me, simple NORM is a wasted SSB button as I never use a 100 - 2900 Hz BW. And it would be nice if there was a default SSB center for each of the filters in Filter configuration. Tapping XFIL would not only move to the next filter, but also set to it's optimal SSB filter center frequency. John, KN5L __ 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 Filter question - SSB
On 11/10/2011 3:33 PM, John Oppenheimer wrote: I use a 1200 Hz center frequency with my 1800 Hz roofing filter. It gives roughly the same passband as my ancient FT-101E with a cascaded pair of Yaesu filters, one in the normal receive line and the second in the speech clipper. Dunc, W5DC Which leads into a K3 issue. I believe that it would be a service to all of us users if the K3 manual had a set of optimal center frequencies for some of the pseudo standard settings optimized by those before us at Heathkit, Collins, and others. And it would be nice if the NORM button was programmable. I understand that there are the NORM1 and NORM2 settings, but for me, simple NORM is a wasted SSB button as I never use a 100 - 2900 Hz BW. And it would be nice if there was a default SSB center for each of the filters in Filter configuration. Tapping XFIL would not only move to the next filter, but also set to it's optimal SSB filter center frequency. John, KN5L __ 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 Filter question - SSB
Al Lorona wrote: 1.8 kHz is deemed better than 2.1 kHz, and 1.5 kHz is deemed better than both. But at some point intelligibility itself suffers because you start to eliminate the signal you're trying to copy in the first place. I for one suffer from a type of listener's fatigue when forced to copy SSB signals in anything less than about 2.2 kHz or so. Others folks suffer from hearing loss and need to hear as much of the voice frequencies as possible. 1.8 kHz just doesn't work for many of these folks. Here's some more individual data. Although my hearing cuts off sharply at about 2.5kHz, I love the 1.8kHz crystal filter for heavy QRM. That Inrad filter was originally purchased for the 'narrow SSB' slot of my old FT-1000MP, and I'm so glad that I kept it for the K3. The 1.8kHz filter also works very well for my wife and other guest operators who don't have hearing loss. In our typical contest QRM conditions (running W/VE with the whole of Continental Europe right behind us) the narrower filter helps to eliminate the high-pitched splatter which we find the most tiring. Unlike a 1.8kHz DSP filter with a 2.5kHz roofing filter, the 1.8kHz crystal filter also avoids artefacts caused by pumping of the hardware AGC loop by strong signals in the gaps between the wider and the narrower passband. The 1.8kHz filter does require careful initial setting of the center frequency to obtain the best possible intelligibility; but those settings will then require very little further adjustment. In other words, they make a very effective working compromise to maximize the QSO rate. The 1.8kHz crystal filter is switched in at a DSP setting of 1.9kHz to avoid excessive narrowing of the passband. I would certainly agree that 1.5kHz is too narrow, because almost every voice would then require its own critical tuning. If you're okay with such narrow bandwidths, more power to you, but you can't make blanket statements about them being equally effective for everybody. But neither can anyone else make blanket statements about them being INeffective. The fairest that anyone can say is, If you don't like the 1.8kHz DSP setting, then don't even think about buying the crystal filter. But if you do like 1.8kHz DSP, you might like the crystal filter a lot. -- 73 from Ian GM3SEK http://www.ifwtech.co.uk/g3sek __ 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 Filter question - SSB
Jim Brown wrote: On 11/10/2011 8:34 AM, David Gilbert wrote: there is so much atrocious splatter from crummy rigs or ignorantly adjusted rigs during a major contest YES, YES, YES. that it is truly rare to find such a narrow filter actually being helpful. I also would trade my 1.5 KHz filters for a pair of 1.8 KHz filters in a heartbeat. I strongly agree. I have 1.8 kHz filters in my K3s, and find that I rarely use them during a contest for the reasons that W4ZV has articulated. Paraphrasing from another world, it's the TRASH, stupid! Forgive me, Jim, but claiming that it's only about one single thing will always lead to bad advice. One-line slogans don't even work in politics, and even less so in engineering. Whatever the problem, it's ALWAYS about finding the optimum working balance between several different aspects. In this particular case we are trying maximize the QSO rate by finding the best possible balance between intelligibility, minimum use of front panel controls, longer-term operator fatigue and probably several other factors that will be of genuine importance to some people, at least some of the time. -- 73 from Ian GM3SEK http://www.ifwtech.co.uk/g3sek __ 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 Filter question - SSB
Folks - We are now hitting the single subject posting limit. Please wrap this thread up ASAP. 73, Eric list moderator --- www.elecraft.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] K3 filter question
I tested, as far as I could use my ears, but it is difficult to be sure ( especially being in Londodn, UK, and having S5-S9 noise on all usable bands), I was hoping someone has tried a similar thing, or someone at Elecraft can explain what is happening in such a situation in the radio. E.g. what kind of difference should I look for ? Is it the signal itself altered (and how), or just the passband i.e. some frequencies missing at the end of the passband. In this case, if I set the offset on .88 in and specify the filters as having 2.6 khz width (instead of 2.7), would then the radio behave as that was true, i.e. no different from the configuration I specified, although it is not the true configuration? Or would it be better to leave it at 2.7 ? In any case, thank you everyone for the answers you sent so far, Adi 2E0TTX On 14/04/2011 02:14, pcbyrne wrote: test _ From: Barry N1EU [via Elecraft] [mailto:ml-node+6271081-1705900565-157...@n2.nabble.com] Sent: Wednesday, April 13, 2011 7:19 PM To: pcbyrne Subject: Re: K3 filter question aandrei wrote: I have the 5 pole 2.7 filters for main and sub RX. One filter offset is -.94, the other is -.81 In order to do diversity receive, I have to set them both to about -.88 My question is: what happens when you set a filter offset differently than the one specified (as in my case) ? How is this supposed to influence operation (normal as well as diversity mode) ? How can things be improved, short of buying new filters? By offsetting the 2.7Khz filter center freq, you may incur some slight asymmetry in the passband response at the lower and/or upper knee of the response curve, but the vast majority of the passband will be unaffected. If noticeable, it will be relatively minor. The other options would be to use closer matched 5-pole filters or use 8-pole filters. 73, Barry N1EU _ If you reply to this email, your message will be added to the discussion below: http://elecraft.365791.n2.nabble.com/Re-k3-receive-audio-tp6259940p6271081.h tml To start a new topic under Elecraft, email ml-node+365791-145773984-157...@n2.nabble.com To unsubscribe from Elecraft, click http://elecraft.365791.n2.nabble.com/template/NamlServlet.jtp?macro=unsubsc ribe_by_codenode=365791code=dzdubWRAdHdpbmxha2VzLWFyLnVzfDM2NTc5MXwxMDQyOT EzOTY1 here. -- View this message in context: http://elecraft.365791.n2.nabble.com/Re-k3-receive-audio-tp6259940p6271190.html Sent from the Elecraft 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 filter question
aandrei wrote: I tested, as far as I could use my ears, but it is difficult to be sure ( especially being in Londodn, UK, and having S5-S9 noise on all usable bands), I was hoping someone has tried a similar thing, or someone at Elecraft can explain what is happening in such a situation in the radio. E.g. what kind of difference should I look for ? Is it the signal itself altered (and how), or just the passband i.e. some frequencies missing at the end of the passband. In this case, if I set the offset on .88 in and specify the filters as having 2.6 khz width (instead of 2.7), would then the radio behave as that was true, i.e. no different from the configuration I specified, although it is not the true configuration? Or would it be better to leave it at 2.7 ? Definitely leave it at 2.7! I believe the firmware looks for either 2.7 (5-pole BW) or 2.8 (8-pole BW) for the TX filter so you might not be able to transmit with 2.6 selected. As Don W3FPR already stated, it is extremely unlikely most people could tell the difference with the filters offset by 70 Hz at the edge of the passband. (Standing by for the audiophile rebuttals now...) 73, Bill -- View this message in context: http://elecraft.365791.n2.nabble.com/Re-k3-receive-audio-tp6259940p6273066.html Sent from the Elecraft 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 filter question
aandrei wrote: I have the 5 pole 2.7 filters for main and sub RX. One filter offset is -.94, the other is -.81 In order to do diversity receive, I have to set them both to about -.88 My question is: what happens when you set a filter offset differently than the one specified (as in my case) ? How is this supposed to influence operation (normal as well as diversity mode) ? How can things be improved, short of buying new filters? By offsetting the 2.7Khz filter center freq, you may incur some slight asymmetry in the passband response at the lower and/or upper knee of the response curve, but the vast majority of the passband will be unaffected. If noticeable, it will be relatively minor. The other options would be to use closer matched 5-pole filters or use 8-pole filters. 73, Barry N1EU -- View this message in context: http://elecraft.365791.n2.nabble.com/Re-k3-receive-audio-tp6259940p6271081.html Sent from the Elecraft 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 filter question
Adi, How much you can fool the offset depends on the filter bandwidth. 70 Hz is a small percentage (2.6%) of a 2.7 kHz bandwdth - you will hardly notice the difference, and if you do, you have very good ears, or are using instruments to measure it - most of us simply use our ears for SSB. For a 400 Hz filter width, 70 Hz makes a big difference (17,5%), so if you want to operate diversity mode with narrow CW filters, it is best that you have them matched or use only the 8 pole filters. 73, Don W3FPR On 4/13/2011 8:07 PM, Adi Andrei wrote: I have the 5 pole 2.7 filters for main and sub RX. One filter offset is -.94, the other is -.81 In order to do diversity receive, I have to set them both to about -.88 My question is: what happens when you set a filter offset differently than the one specified (as in my case) ? How is this supposed to influence operation (normal as well as diversity mode) ? How can things be improved, short of buying new filters? Thank you, Adi 2E0TTX __ 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 filter question
test _ From: Barry N1EU [via Elecraft] [mailto:ml-node+6271081-1705900565-157...@n2.nabble.com] Sent: Wednesday, April 13, 2011 7:19 PM To: pcbyrne Subject: Re: K3 filter question aandrei wrote: I have the 5 pole 2.7 filters for main and sub RX. One filter offset is -.94, the other is -.81 In order to do diversity receive, I have to set them both to about -.88 My question is: what happens when you set a filter offset differently than the one specified (as in my case) ? How is this supposed to influence operation (normal as well as diversity mode) ? How can things be improved, short of buying new filters? By offsetting the 2.7Khz filter center freq, you may incur some slight asymmetry in the passband response at the lower and/or upper knee of the response curve, but the vast majority of the passband will be unaffected. If noticeable, it will be relatively minor. The other options would be to use closer matched 5-pole filters or use 8-pole filters. 73, Barry N1EU _ If you reply to this email, your message will be added to the discussion below: http://elecraft.365791.n2.nabble.com/Re-k3-receive-audio-tp6259940p6271081.h tml To start a new topic under Elecraft, email ml-node+365791-145773984-157...@n2.nabble.com To unsubscribe from Elecraft, click http://elecraft.365791.n2.nabble.com/template/NamlServlet.jtp?macro=unsubsc ribe_by_codenode=365791code=dzdubWRAdHdpbmxha2VzLWFyLnVzfDM2NTc5MXwxMDQyOT EzOTY1 here. -- View this message in context: http://elecraft.365791.n2.nabble.com/Re-k3-receive-audio-tp6259940p6271190.html Sent from the Elecraft 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 Filter Question
My setup is as follows: Main: 13k, 6k, 2.7k, 500Hz Sub: 13k, 2.7k, 500Hz I also have the wide-receive module installed on the sub. This way the sub receiver will have broad coverage while the main is strictly relegated to the amateur bands. It works quite well as the 13k filter in the sub does double duty for FM and AM receive. 73 de James K2QI -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Brett Howard Sent: Thursday, July 09, 2009 1:31 AM To: elecraft@mailman.qth.net Subject: [Elecraft] K3 Filter Question Ok so I'm curious if I'll be able to do what I'd like. I'd like to setup my K3 for maximum flexibility. At the moment I have these filters. 2.8Khz 1.8Khz 1Khz 250Hz These 4 filters are duplicated in the lower 4 slots of both receivers. I'd like to have the ability to do AM and FM both TX and RX in this radio. Can I add the AM filter and KBPF into the main RX and then put the FM filter into the KRX3? I'm hoping that I can then use the MainRX for broad frequency coverage and AM broadcast receive. Then if I ever want to do FM work I simply have to use the sub receiver to do so. Will TX through the FM filter work with it in the sub RX... To the best of my knowledge it appears that I can set the rig up in this fashion but that doesn't always mean it will work how I expect it to. Am I all wet here? Thanks ~Brett __ 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 Filter Question
Manual, pg 74: Rule #1: If you plan to use a particular filter for both transmitting and receiving (main receiver), you’ll need to install it on the RF board. You can optionally install a filter of the same or similar bandwidth on the sub receiver for receive-only use. (This is recommended since it will keep the receivers identical.) Bob NW8L On Wed, Jul 8, 2009 at 11:31 PM, Brett Howardbr...@livecomputers.com wrote: Ok so I'm curious if I'll be able to do what I'd like. I'd like to setup my K3 for maximum flexibility. At the moment I have these filters. 2.8Khz 1.8Khz 1Khz 250Hz These 4 filters are duplicated in the lower 4 slots of both receivers. I'd like to have the ability to do AM and FM both TX and RX in this radio. Can I add the AM filter and KBPF into the main RX and then put the FM filter into the KRX3? I'm hoping that I can then use the MainRX for broad frequency coverage and AM broadcast receive. Then if I ever want to do FM work I simply have to use the sub receiver to do so. Will TX through the FM filter work with it in the sub RX... To the best of my knowledge it appears that I can set the rig up in this fashion but that doesn't always mean it will work how I expect it to. Am I all wet here? Thanks ~Brett __ 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 Filter Question
I forgot to go back to that... I was thrown off by the comment on the order page that said you only need one of each filter for transmit. I know that doesn't fully say what I was hoping for though I wonder if there is any possibility of allowing AM TX and/or ESSB via the FM filter... As I'd like to have maximum flexibility but only have one slot left because of the way I have setup the radio for what I spend most of my time doing. Thanks for the assistance gentlemen. ~Brett On Thu, 2009-07-09 at 00:13 -0600, Bob Cunnings wrote: Manual, pg 74: Rule #1: If you plan to use a particular filter for both transmitting and receiving (main receiver), you’ll need to install it on the RF board. You can optionally install a filter of the same or similar bandwidth on the sub receiver for receive-only use. (This is recommended since it will keep the receivers identical.) Bob NW8L On Wed, Jul 8, 2009 at 11:31 PM, Brett Howardbr...@livecomputers.com wrote: Ok so I'm curious if I'll be able to do what I'd like. I'd like to setup my K3 for maximum flexibility. At the moment I have these filters. 2.8Khz 1.8Khz 1Khz 250Hz These 4 filters are duplicated in the lower 4 slots of both receivers. I'd like to have the ability to do AM and FM both TX and RX in this radio. Can I add the AM filter and KBPF into the main RX and then put the FM filter into the KRX3? I'm hoping that I can then use the MainRX for broad frequency coverage and AM broadcast receive. Then if I ever want to do FM work I simply have to use the sub receiver to do so. Will TX through the FM filter work with it in the sub RX... To the best of my knowledge it appears that I can set the rig up in this fashion but that doesn't always mean it will work how I expect it to. Am I all wet here? Thanks ~Brett __ 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 __ 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 Filter Question
Brett I do have all the slots filled with roofers and the FL1 in my case its an 8 poles 6.0 Khz,with that I am able to TX and RX on AM but not on FM,if you want to be able to use either AM or FM RX/TX you will have to purchase the FM filter of 13Khz BW.Hope this answer your doubt. AD4C K3 # 2192 The difference between genius and stupidity is that genius has its limits.. -- Albert Einstein --- On Thu, 7/9/09, Brett Howard br...@livecomputers.com wrote: From: Brett Howard br...@livecomputers.com Subject: Re: [Elecraft] K3 Filter Question To: Bob Cunnings bob.cunni...@gmail.com Cc: elecraft@mailman.qth.net Date: Thursday, July 9, 2009, 6:20 AM I forgot to go back to that... I was thrown off by the comment on the order page that said you only need one of each filter for transmit. I know that doesn't fully say what I was hoping for though I wonder if there is any possibility of allowing AM TX and/or ESSB via the FM filter... As I'd like to have maximum flexibility but only have one slot left because of the way I have setup the radio for what I spend most of my time doing. Thanks for the assistance gentlemen. ~Brett On Thu, 2009-07-09 at 00:13 -0600, Bob Cunnings wrote: Manual, pg 74: Rule #1: If you plan to use a particular filter for both transmitting and receiving (main receiver), you’ll need to install it on the RF board. You can optionally install a filter of the same or similar bandwidth on the sub receiver for receive-only use. (This is recommended since it will keep the receivers identical.) Bob NW8L On Wed, Jul 8, 2009 at 11:31 PM, Brett Howardbr...@livecomputers.com wrote: Ok so I'm curious if I'll be able to do what I'd like. I'd like to setup my K3 for maximum flexibility. At the moment I have these filters. 2.8Khz 1.8Khz 1Khz 250Hz These 4 filters are duplicated in the lower 4 slots of both receivers. I'd like to have the ability to do AM and FM both TX and RX in this radio. Can I add the AM filter and KBPF into the main RX and then put the FM filter into the KRX3? I'm hoping that I can then use the MainRX for broad frequency coverage and AM broadcast receive. Then if I ever want to do FM work I simply have to use the sub receiver to do so. Will TX through the FM filter work with it in the sub RX... To the best of my knowledge it appears that I can set the rig up in this fashion but that doesn't always mean it will work how I expect it to. Am I all wet here? Thanks ~Brett __ 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 __ 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 Filter Question
I wonder if there is any possibility of allowing AM TX and/or ESSB via the FM filter... It is theoretically possible to transmit AM and ESSB through the FM filter but the K3 is currently configured to prohibit AM and ESSB transmit unless the 6 KHz filter is used. I have transmitted using the FM filter by setting the K3 as if the FM filter was an AM filter but then I can not transmit FM without resetting the filter set-up. Elecraft will argue that the 6 KHz filter is necessary to prevent transmitted images (the DSP IF is 15 KHz, the image is 30 KHz away from the transmit frequency). However, I can not measure any image - to -120 dB from the CW level - when looking at the transmitter output with a directional coupler using the SDR-IQ as a spectrum analyzer. This is as expected since the FM filter should be at least -60 dB at +/-23 (2:1 shape factor) with an ultimate attenuation of at least -100 dB. It would certainly be nice if the 6 KHz restriction was removed. 73, ... Joe, W4TV -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Brett Howard Sent: Thursday, July 09, 2009 2:21 AM To: Bob Cunnings Cc: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 Filter Question I forgot to go back to that... I was thrown off by the comment on the order page that said you only need one of each filter for transmit. I know that doesn't fully say what I was hoping for though I wonder if there is any possibility of allowing AM TX and/or ESSB via the FM filter... As I'd like to have maximum flexibility but only have one slot left because of the way I have setup the radio for what I spend most of my time doing. Thanks for the assistance gentlemen. ~Brett On Thu, 2009-07-09 at 00:13 -0600, Bob Cunnings wrote: Manual, pg 74: Rule #1: If you plan to use a particular filter for both transmitting and receiving (main receiver), you’ll need to install it on the RF board. You can optionally install a filter of the same or similar bandwidth on the sub receiver for receive-only use. (This is recommended since it will keep the receivers identical.) Bob NW8L On Wed, Jul 8, 2009 at 11:31 PM, Brett Howardbr...@livecomputers.com wrote: Ok so I'm curious if I'll be able to do what I'd like. I'd like to setup my K3 for maximum flexibility. At the moment I have these filters. 2.8Khz 1.8Khz 1Khz 250Hz These 4 filters are duplicated in the lower 4 slots of both receivers. I'd like to have the ability to do AM and FM both TX and RX in this radio. Can I add the AM filter and KBPF into the main RX and then put the FM filter into the KRX3? I'm hoping that I can then use the MainRX for broad frequency coverage and AM broadcast receive. Then if I ever want to do FM work I simply have to use the sub receiver to do so. Will TX through the FM filter work with it in the sub RX... To the best of my knowledge it appears that I can set the rig up in this fashion but that doesn't always mean it will work how I expect it to. Am I all wet here? Thanks ~Brett __ 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 __ 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 Filter Question
I agree. The cost of the K3 filters is now so high in the UK, that I want to get away with the minimum number necessary. 73 Stewart G3RXQ On Thu, 9 Jul 2009 10:00:42 -0400, Joe Subich, W4TV wrote: I wonder if there is any possibility of allowing AM TX and/or ESSB via the FM filter... It is theoretically possible to transmit AM and ESSB through the FM filter but the K3 is currently configured to prohibit AM and ESSB transmit unless the 6 KHz filter is used. I have transmitted using the FM filter by setting the K3 as if the FM filter was an AM filter but then I can not transmit FM without resetting the filter set-up. Elecraft will argue that the 6 KHz filter is necessary to prevent transmitted images (the DSP IF is 15 KHz, the image is 30 KHz away from the transmit frequency). However, I can not measure any image - to -120 dB from the CW level - when looking at the transmitter output with a directional coupler using the SDR-IQ as a spectrum analyzer. This is as expected since the FM filter should be at least -60 dB at +/-23 (2:1 shape factor) with an ultimate attenuation of at least -100 dB. It would certainly be nice if the 6 KHz restriction was removed. 73, ... Joe, W4TV -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Brett Howard Sent: Thursday, July 09, 2009 2:21 AM To: Bob Cunnings Cc: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 Filter Question I forgot to go back to that... I was thrown off by the comment on the order page that said you only need one of each filter for transmit. I know that doesn't fully say what I was hoping for though I wonder if there is any possibility of allowing AM TX and/or ESSB via the FM filter... As I'd like to have maximum flexibility but only have one slot left because of the way I have setup the radio for what I spend most of my time doing. Thanks for the assistance gentlemen. ~Brett On Thu, 2009-07-09 at 00:13 -0600, Bob Cunnings wrote: Manual, pg 74: Rule #1: If you plan to use a particular filter for both transmitting and receiving (main receiver), you'll need to install it on the RF board. You can optionally install a filter of the same or similar bandwidth on the sub receiver for receive-only use. (This is recommended since it will keep the receivers identical.) Bob NW8L On Wed, Jul 8, 2009 at 11:31 PM, Brett Howardbr...@livecomputers.com wrote: Ok so I'm curious if I'll be able to do what I'd like. I'd like to setup my K3 for maximum flexibility. At the moment I have these filters. 2.8Khz 1.8Khz 1Khz 250Hz These 4 filters are duplicated in the lower 4 slots of both receivers. I'd like to have the ability to do AM and FM both TX and RX in this radio. Can I add the AM filter and KBPF into the main RX and then put the FM filter into the KRX3? I'm hoping that I can then use the MainRX for broad frequency coverage and AM broadcast receive. Then if I ever want to do FM work I simply have to use the sub receiver to do so. Will TX through the FM filter work with it in the sub RX... To the best of my knowledge it appears that I can set the rig up in this fashion but that doesn't always mean it will work how I expect it to. Am I all wet here? Thanks ~Brett __ 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 __ 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 __ 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
Re: [Elecraft] K3 Filter Question
This is as expected since the FM filter should be at least -60 dB at +/-23 (2:1 shape factor) with an ultimate attenuation of at least -100 dB. Correction ... +/- 26 KHz or a 2:1 shape factor. However for comparison, Inrad's six pole front end filters for 40 meters are 15 KHz wide (+/- 7.5 KHz) at 1 dB and 32 KHz (+/- 16 KHz) at - 60 dB or 20 KHz ((+/- 10 KHz) at -1 dB and 45 KHz (+/- 22.5 KHz) at - 60 dB. Converting to a 6:60 framework makes the shape factor around 1.8:1. 73, ... Joe, W4TV -Original Message- From: Stewart Baker [mailto:stew...@baker.nildram.co.uk] Sent: Thursday, July 09, 2009 10:35 AM To: li...@subich.com; 'Brett Howard'; 'Bob Cunnings' Cc: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 Filter Question I agree. The cost of the K3 filters is now so high in the UK, that I want to get away with the minimum number necessary. 73 Stewart G3RXQ On Thu, 9 Jul 2009 10:00:42 -0400, Joe Subich, W4TV wrote: I wonder if there is any possibility of allowing AM TX and/or ESSB via the FM filter... It is theoretically possible to transmit AM and ESSB through the FM filter but the K3 is currently configured to prohibit AM and ESSB transmit unless the 6 KHz filter is used. I have transmitted using the FM filter by setting the K3 as if the FM filter was an AM filter but then I can not transmit FM without resetting the filter set-up. Elecraft will argue that the 6 KHz filter is necessary to prevent transmitted images (the DSP IF is 15 KHz, the image is 30 KHz away from the transmit frequency). However, I can not measure any image - to -120 dB from the CW level - when looking at the transmitter output with a directional coupler using the SDR-IQ as a spectrum analyzer. This is as expected since the FM filter should be at least -60 dB at +/-23 (2:1 shape factor) with an ultimate attenuation of at least -100 dB. It would certainly be nice if the 6 KHz restriction was removed. 73, ... Joe, W4TV -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Brett Howard Sent: Thursday, July 09, 2009 2:21 AM To: Bob Cunnings Cc: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 Filter Question I forgot to go back to that... I was thrown off by the comment on the order page that said you only need one of each filter for transmit. I know that doesn't fully say what I was hoping for though I wonder if there is any possibility of allowing AM TX and/or ESSB via the FM filter... As I'd like to have maximum flexibility but only have one slot left because of the way I have setup the radio for what I spend most of my time doing. Thanks for the assistance gentlemen. ~Brett On Thu, 2009-07-09 at 00:13 -0600, Bob Cunnings wrote: Manual, pg 74: Rule #1: If you plan to use a particular filter for both transmitting and receiving (main receiver), you'll need to install it on the RF board. You can optionally install a filter of the same or similar bandwidth on the sub receiver for receive-only use. (This is recommended since it will keep the receivers identical.) Bob NW8L On Wed, Jul 8, 2009 at 11:31 PM, Brett Howardbr...@livecomputers.com wrote: Ok so I'm curious if I'll be able to do what I'd like. I'd like to setup my K3 for maximum flexibility. At the moment I have these filters. 2.8Khz 1.8Khz 1Khz 250Hz These 4 filters are duplicated in the lower 4 slots of both receivers. I'd like to have the ability to do AM and FM both TX and RX in this radio. Can I add the AM filter and KBPF into the main RX and then put the FM filter into the KRX3? I'm hoping that I can then use the MainRX for broad frequency coverage and AM broadcast receive. Then if I ever want to do FM work I simply have to use the sub receiver to do so. Will TX through the FM filter work with it in the sub RX... To the best of my knowledge it appears that I can set the rig up in this fashion but that doesn't always mean it will work how I expect it to. Am I all wet here? Thanks ~Brett __ 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
Re: [Elecraft] K3 Filter Question
Looks like buying the FM filter and lying to the rig gives me the maximum flexibility with a minor inconvenience. Being that I won't be TXing in those modes all that often I'm not too worred but I just want to have a true All mode tranceiver. ~Brett On Thu, 2009-07-09 at 11:35 -0400, Joe Subich, W4TV wrote: This is as expected since the FM filter should be at least -60 dB at +/-23 (2:1 shape factor) with an ultimate attenuation of at least -100 dB. Correction ... +/- 26 KHz or a 2:1 shape factor. However for comparison, Inrad's six pole front end filters for 40 meters are 15 KHz wide (+/- 7.5 KHz) at 1 dB and 32 KHz (+/- 16 KHz) at - 60 dB or 20 KHz ((+/- 10 KHz) at -1 dB and 45 KHz (+/- 22.5 KHz) at - 60 dB. Converting to a 6:60 framework makes the shape factor around 1.8:1. 73, ... Joe, W4TV -Original Message- From: Stewart Baker [mailto:stew...@baker.nildram.co.uk] Sent: Thursday, July 09, 2009 10:35 AM To: li...@subich.com; 'Brett Howard'; 'Bob Cunnings' Cc: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 Filter Question I agree. The cost of the K3 filters is now so high in the UK, that I want to get away with the minimum number necessary. 73 Stewart G3RXQ On Thu, 9 Jul 2009 10:00:42 -0400, Joe Subich, W4TV wrote: I wonder if there is any possibility of allowing AM TX and/or ESSB via the FM filter... It is theoretically possible to transmit AM and ESSB through the FM filter but the K3 is currently configured to prohibit AM and ESSB transmit unless the 6 KHz filter is used. I have transmitted using the FM filter by setting the K3 as if the FM filter was an AM filter but then I can not transmit FM without resetting the filter set-up. Elecraft will argue that the 6 KHz filter is necessary to prevent transmitted images (the DSP IF is 15 KHz, the image is 30 KHz away from the transmit frequency). However, I can not measure any image - to -120 dB from the CW level - when looking at the transmitter output with a directional coupler using the SDR-IQ as a spectrum analyzer. This is as expected since the FM filter should be at least -60 dB at +/-23 (2:1 shape factor) with an ultimate attenuation of at least -100 dB. It would certainly be nice if the 6 KHz restriction was removed. 73, ... Joe, W4TV -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Brett Howard Sent: Thursday, July 09, 2009 2:21 AM To: Bob Cunnings Cc: elecraft@mailman.qth.net Subject: Re: [Elecraft] K3 Filter Question I forgot to go back to that... I was thrown off by the comment on the order page that said you only need one of each filter for transmit. I know that doesn't fully say what I was hoping for though I wonder if there is any possibility of allowing AM TX and/or ESSB via the FM filter... As I'd like to have maximum flexibility but only have one slot left because of the way I have setup the radio for what I spend most of my time doing. Thanks for the assistance gentlemen. ~Brett On Thu, 2009-07-09 at 00:13 -0600, Bob Cunnings wrote: Manual, pg 74: Rule #1: If you plan to use a particular filter for both transmitting and receiving (main receiver), you'll need to install it on the RF board. You can optionally install a filter of the same or similar bandwidth on the sub receiver for receive-only use. (This is recommended since it will keep the receivers identical.) Bob NW8L On Wed, Jul 8, 2009 at 11:31 PM, Brett Howardbr...@livecomputers.com wrote: Ok so I'm curious if I'll be able to do what I'd like. I'd like to setup my K3 for maximum flexibility. At the moment I have these filters. 2.8Khz 1.8Khz 1Khz 250Hz These 4 filters are duplicated in the lower 4 slots of both receivers. I'd like to have the ability to do AM and FM both TX and RX in this radio. Can I add the AM filter and KBPF into the main RX and then put the FM filter into the KRX3? I'm hoping that I can then use the MainRX for broad frequency coverage and AM broadcast receive. Then if I ever want to do FM work I simply have to use the sub receiver to do so. Will TX through the FM filter work with it in the sub RX... To the best of my knowledge it appears that I can set the rig up in this fashion but that doesn't always mean it will work how I expect it to. Am I all wet here? Thanks ~Brett __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm
Re: [Elecraft] K3 Filter question
Jeff, If and only if you are doing diversity receive, then the mismatched filters would be noticeable. If they are not far apart, you can 'cheat' a little on the filter offsets - set both of them the same (to the average of the two offsets) and you are not likely to notice. If you have the narrow filters, then the effect of this compromise will be worse, but you stated that you had only the stock filters, so there will not be much difference for the 2.7 kHz filters. A few Hz one way or another does not have much impact on a 2.7 kHz bandpass, but it can be a worse problem with a 200 Hz bandpass. If you are not doing diversity receive, I do not think you will notice a difference even with the narrow filters. 73, Don W3FPR Jeff Wandling W7BRS wrote: I misunderstood the previous thread on matched filters. When I receive the KRX3 after assembling the K3, do I worry about the stock filters on the K3/100 and KRX3 being mis-matched? Does it matter? If it doesn't make that much difference for general use, then that's all I'm wondering. I'm not a QST lab type station. -jeff W7BRS ___ 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 Filter Question?
Mostly I think it is just a consistency thing having all 8 pole or having all 5 pole. Ive had both in my K-3. There really isnt a difference between the 2.7 and 2.8. I can hear some slight difference but It's not significant. Im sure the number crunchers will have different opinions mine is just based on what I hear in the radio. I have the 2.8 in now. I decided to splurge. For the K-3 I have right now Ill stick with 8 poles. The second k-3 on order I may just go with 5 poles. YMMV Mike/aj9c Craig KA0CT wrote: Why woould you swap out the 2.7 ilter for the 2.8 filter. What do you acheive with the switck ___ 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