Re: Re: [Elecraft] Hearing the effect of narrower roofing filter
But if you leave the setting at its nominal, can you hear the difference as that bandwidth is selected? I'm not sure I understand the advantage you are gaining by bringing the crystal filter in later; I'll do if there's something to be gained, it sounds an interesting approach. David G3UNA David, Say that you have a 500 Hz (nominal) roofing filter with an (actual) 6-dB bandwidth of 550 Hz. When you choose the widest DSP bandwidth at which this roofing filter kicks in, here is what I think about the choices you have: 1. You have it kick in at 550 Hz DSP because it matches the DSP bandwidth. This may create the steepest slopes, but I would avoid it for digital modes since I would expect the group delays to vary near the flanks of the xtal filter, but not near the flanks of the (FIR) DSP filter. 2. You have it kick in at 500 Hz DSP because it is a 500 Hz filter. This logic makes no sense, since the xtal filter is actually 550 Hz. 3. You have it kick in at 500 Hz or less DSP because you want the DSP to cut away the group-delay-varying portion of the xtal filter passband. This would make sense. How much of the xtal filter response would of course depend on the group delay characteristics of the particular xtal filter. Of course if you don't use digital modes, you may want to go with approach #1. 4. You have it kick in at 600 Hz or above. Someone on the list suggested that this approach made the receiver sound more pleasant. The effect would essentially be to disable the DSP for receive purposes, except for the DSP's big improvement in ultimate rejection, and any bandwidth-unrelated DSP function that may be enabled. I have yet to hear for myself, but operating this way makes little sense to me unless there is something wrong with the DSP release. As to my original question, it seems that most respondents like to vary the DSP bandwidth as a means of switching the narrow xtal filter in and out, and to do this without lots of strong closeby signals. If the xtal filter kicks in according to #1 above, the composite bandwith of the two 550-Hz filters will be much less than 550 Hz. This will of course create an exaggerated effect of reducing the noise you hear, and here is an obvious risk of giving the narrow xtal filter way too much credit. If instead the kick-in point is set according to #3, you would reduce the effect of cascading on the overall bandwidth, and results would be more meaningful. However, as has been pointed out, it would be necessary to carefully adjust the gain for the xtal filter. Also, you would have to somehow work around the variations in effective DSP bandwidth step size, which have been stated to differ from the expected 50 Hz steps (at every 200 Hz?). Anyway, what I really wanted to know was NOT how the filters sound with just background hiss or average signals on the band. The justification for the narrow roofing filter would exist only if very strong interfering signal levels get through the standard roofing filter. I am thinking CW, and in case there is only one such signal, the AGC pumping would be easy to recognize. My understanding is that with current production K3's this would happen for an interfering signal level of somewhere around 25 to 30 dB over S9. In my mind, the interesting question is the case where there are multiple interfering signals within the roofing filter passband, including qrn etc. Even though these would not add up coherently, the peak voltage would grow with the number of signals, such that the ADC overload level would be reached without any individual signal reaching the 25 or 30 dB over S9. This suggests that the hardware AGC ideally should have an extremely fast attack time, and I assume that it does. When the hardware AGC responds under these conditions, I am guessing that the effect might be an increase in the general background noise heard. This is really what I was after. -- View this message in context: http://n2.nabble.com/Hearing-the-effect-of-narrower-roofing-filter-tp470635p795233.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: Re: [Elecraft] Hearing the effect of narrower roofing filter
When the hardware AGC responds under these conditions, I am guessing that the effect might be an increase in the general background noise heard. This is really what I was after. After looking at the clock last night and finishing off my post too quickly, I got poster's remorse about the last sentence. Of course, if the hardware agc works perfectly, I would expect the general effect to be a decrease in noise. Behind my sentence were two muddled thoughts: 1. If the agc hang or decay is very short, the random peaks in composite signal might cause very rapid sequences of normal/desensed noise, and this staccato effect might be perceived as an addition in noise although not increasing noise amplitude, and 2. This being a new radio design, it would not be inconceivable if some aspect of the agc design were flawed, resulting in actual increases in noise amplitude when the hardware agc kicks in repeatedly at a high rate. I received one response, off-list, that was aimed at this part of my post. The gentleman provided a great deal of insight into what might go wrong with the agc action and the second mixer. Those details went far beyond my thoughts. Unfortunately he did not actually have a K3, so there was no test data. I guess I had better be patient and wait until my K3 arrives! It should be easy to study the hardware agc action by using an external preamp to bring up the average signal level on a crowded band. I might hang one scope channel on the 8 MHz signal after the filter, and another channel on the hardware agc voltage, while listening to the radio. Of course, since noone on the list is obsessing about this aspect of K3 behavior, it will probably turn out to be unimportant to the overall performance of the radio. -- View this message in context: http://n2.nabble.com/Hearing-the-effect-of-narrower-roofing-filter-tp470635p795880.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: Re: [Elecraft] Hearing the effect of narrower roofing filter
Fine observations when you change the filter setting knob, but what makes you think you are hearing the effect of the roofing filter and not the dsp filter? David G3UNA From: hank k8dd [EMAIL PROTECTED] Date: 2008/07/08 Tue PM 02:29:08 BST To: Jan Erik Holm [EMAIL PROTECTED] CC: elecraft@mailman.qth.net Subject: Re: [Elecraft] Hearing the effect of narrower roofing filter - Original Message - From: Jan Erik Holm [EMAIL PROTECTED] Cc: elecraft@mailman.qth.net Sent: Tuesday, July 08, 2008 8:31 AM Subject: Re: [Elecraft] Hearing the effect of narrower roofing filter Darwin, Keith wrote: each step. When I step to 500 Hz and the narrow roofing filter kicks in, I can hear a distinct change, more than just the DSP narrowing I'd heard while stepping from 1000 Hz to 550 Hz. The effect is very noticeable. - Keith N1AS - - K3 711 - Keith, Can you describe this change closer. 73 Jim SM2EKM Get two pieces of plastic pipe about a foot long. One six inches in diameter. One three inche in diameter. Close one eye and look at the mountains in the horizon and you will see a wide view. 6000 Hz Put the six inch pipe up to the other eye. You will see a portion of the horizon - like 1000 Hz. Put the three inch pipe up to your eye. 500 Hz. The effect, as Keith says, is very noticeable! 73HankK8DD GET FREE SMILEYS FOR YOUR IM EMAIL - Learn more at http://www.inbox.com/smileys Works with AIM®, MSN® Messenger, Yahoo!® Messenger, ICQ®, Google TalkT and most webmails ___ 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 - Email sent from www.virginmedia.com/email Virus-checked using McAfee(R) Software and scanned for spam ___ 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: Re: [Elecraft] Hearing the effect of narrower roofing filter
Not sure, David, if your Q was to me or to Hank. I can only answer for me. When I adjust the filter width knob, I'm most definitely hearing the combined effect of the DSP bandwidth reduction and the change in roofing filters. But, since I can change DSP without changing the roofing filter (by stepping from 1500 Hz down to 550 Hz) I can get a good feel for how the DSP filter sounds. Then, stepping to 500 Hz, I can see the combined effect of one more DSP step plus the insertion of the 500 Hz roofing filter. The observed big change from 550 Hz to 500 Hz is *mostly* due to the roofing filter. - Keith N1AS - - K3 711 - Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Fine observations when you change the filter setting knob, but what makes you think you are hearing the effect of the roofing filter and not the dsp filter? David G3UNA ___ 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: Re: [Elecraft] Hearing the effect of narrower roofing filter
A couple of related points, which may not be new news to anyone: You can set the K3's filter bandwidth configuration to cause the roofing filter to switch at points other than the bandwidth printed on the filter. Maybe you would like your (nominally) 500 Hz filter to switch in at 450 or 550 Hz. My 8-pole 250 Hz filter is a bit broader than 250 Hz, and I've set it to switch at 300 Hz. You can also turn off a filter (set its bandwidth to zero temporarily) to evaluate whether a change you're hearing is due to the roofing filter or the change in bandwidth provided by the DSP. And you should attempt to adjust the filter gain compensation so that there is no change in the volume of the note you're tuned to. Rene, who guides the assembly of K3s built by Elecraft, told me that he uses a voltmeter on the speaker terminals when adjusting the gain compensation and can get usually get within a half decibel. I notice a definite qualitative change as the narrower filters switch in. It sounds quieter, and it seems like the volume is being turned down. I think I'm responding to the reduced low and high frequency components that are supposed to be cut off. The DSP-related changes seem more gradual. Dick, K6KR -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Darwin, Keith Sent: Tuesday, July 08, 2008 7:43 AM To: elecraft@mailman.qth.net Subject: RE: Re: [Elecraft] Hearing the effect of narrower roofing filter Not sure, David, if your Q was to me or to Hank. I can only answer for me. When I adjust the filter width knob, I'm most definitely hearing the combined effect of the DSP bandwidth reduction and the change in roofing filters. But, since I can change DSP without changing the roofing filter (by stepping from 1500 Hz down to 550 Hz) I can get a good feel for how the DSP filter sounds. Then, stepping to 500 Hz, I can see the combined effect of one more DSP step plus the insertion of the 500 Hz roofing filter. The observed big change from 550 Hz to 500 Hz is *mostly* due to the roofing filter. - Keith N1AS - - K3 711 - Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Fine observations when you change the filter setting knob, but what makes you think you are hearing the effect of the roofing filter and not the dsp filter? David G3UNA ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.138 / Virus Database: 270.4.6/1540 - Release Date: 7/8/2008 6:33 AM No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.138 / Virus Database: 270.4.6/1540 - Release Date: 7/8/2008 6:33 AM ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: Re: [Elecraft] Hearing the effect of narrower roofing filter
K6KR wrote: I notice a definite qualitative change as the narrower filters switch in. It sounds quieter, and it seems like the volume is being turned down. I think I'm responding to the reduced low and high frequency components that are supposed to be cut off. The DSP-related changes seem more gradual. Dick made some very good points about using the K3Utility to enable different filters and about the need to set gain correctly for each filter. Here's a simple test that may surprise you: 1. Disable all filters but your 2.7 or 2.8 for CW (using Dick's K3Utility). 2. SLOWLY rotate WIDTH from 1.5 to 0.05. 3. Note how the character of the noise changes. I find abrupt changes in noise character between some DSP settings...and this is *not* due to the roofing filter since that is held constant at 2.7k. The abrupt changes I hear using a 350 Hz CW pitch setting are: 1.1 - 1.0 0.90-0.85 0.70-0.65 0.50-0.45 0.30-0.25 0.20-0.15 Do you see a pattern in the above? I hear something which repeats almost every 0.20 increment...(and I bet Lyle can explain why). I recall seeing this on Spectrogram when I was closely looking at DSP BWs shortly after I got my unit. We did discover some serious offset problems at the low end (which Lyle has since fixed), but I recall the DSP BW changes were never exactly linear as you reduced BW. This is not a particular concern to me but curious nevertheless. 73, Bill -- View this message in context: http://www.nabble.com/Hearing-the-effect-of-narrower-roofing-filter-tp18329150p18342146.html Sent from the Elecraft mailing list archive at Nabble.com. ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
RE: Re: [Elecraft] Hearing the effect of narrower roofing filter
I agree with this assessment and when I get my rig back plan on upping my 250 filter to kick in at 350. But I had 4dB of gain on the 250 and it still seemed like things got a lot quieter when switching to the 250. I'd have to measure and see if I had the actual same level there (and I can do that now that I have the XG2) :) But I did have 4dB thrown in for good measure! :) I found myself using the 250 all the time for rag chewing... But I use 250 on my K1 for its lowest filter position too.. I tend to generally like things pretty quiet. I use 850 for scanning the band (as that is as wide as the K1 can go). I use 500 to 550 for calling CQ if they're further away than that then I guess I don't get to hear them... And then I crank it down to 200 to 250 when I'm talking with a guy. It not only ensures that I'm pretty close to zero beat with him but also makes things quieter and gets rid of a lot of the electrical hash I have in my area. The K1's noise blanker doesn't hold a candle to the noise in my area but the K3 was doing a pretty fantastic job! On Tue, 2008-07-08 at 08:02 -0700, Dick Dievendorff wrote: A couple of related points, which may not be new news to anyone: You can set the K3's filter bandwidth configuration to cause the roofing filter to switch at points other than the bandwidth printed on the filter. Maybe you would like your (nominally) 500 Hz filter to switch in at 450 or 550 Hz. My 8-pole 250 Hz filter is a bit broader than 250 Hz, and I've set it to switch at 300 Hz. You can also turn off a filter (set its bandwidth to zero temporarily) to evaluate whether a change you're hearing is due to the roofing filter or the change in bandwidth provided by the DSP. And you should attempt to adjust the filter gain compensation so that there is no change in the volume of the note you're tuned to. Rene, who guides the assembly of K3s built by Elecraft, told me that he uses a voltmeter on the speaker terminals when adjusting the gain compensation and can get usually get within a half decibel. I notice a definite qualitative change as the narrower filters switch in. It sounds quieter, and it seems like the volume is being turned down. I think I'm responding to the reduced low and high frequency components that are supposed to be cut off. The DSP-related changes seem more gradual. Dick, K6KR -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Darwin, Keith Sent: Tuesday, July 08, 2008 7:43 AM To: elecraft@mailman.qth.net Subject: RE: Re: [Elecraft] Hearing the effect of narrower roofing filter Not sure, David, if your Q was to me or to Hank. I can only answer for me. When I adjust the filter width knob, I'm most definitely hearing the combined effect of the DSP bandwidth reduction and the change in roofing filters. But, since I can change DSP without changing the roofing filter (by stepping from 1500 Hz down to 550 Hz) I can get a good feel for how the DSP filter sounds. Then, stepping to 500 Hz, I can see the combined effect of one more DSP step plus the insertion of the 500 Hz roofing filter. The observed big change from 550 Hz to 500 Hz is *mostly* due to the roofing filter. - Keith N1AS - - K3 711 - Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Fine observations when you change the filter setting knob, but what makes you think you are hearing the effect of the roofing filter and not the dsp filter? David G3UNA ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.138 / Virus Database: 270.4.6/1540 - Release Date: 7/8/2008 6:33 AM No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.138 / Virus Database: 270.4.6/1540 - Release Date: 7/8/2008 6:33 AM ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com ___ 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: Re: [Elecraft] Hearing the effect of narrower roofing filter
The reason I'm particularly interested is because I fancy doing diversity reception and de-select my roofing filters in the main rx so there is no phase shifting relative to the second rx without filters. Have you de-selected the roofing filters to do a comparison with and without? David G3UNA When I adjust the filter width knob, I'm most definitely hearing the combined effect of the DSP bandwidth reduction and the change in roofing filters. But, since I can change DSP without changing the roofing filter (by stepping from 1500 Hz down to 550 Hz) I can get a good feel for how the DSP filter sounds. Then, stepping to 500 Hz, I can see the combined effect of one more DSP step plus the insertion of the 500 Hz roofing filter. The observed big change from 550 Hz to 500 Hz is *mostly* due to the roofing filter. - Keith N1AS - - K3 711 - ___ 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: Re: [Elecraft] Hearing the effect of narrower roofing filter
But if you leave the setting at its nominal, can you hear the difference as that bandwidth is selected? I'm not sure I understand the advantage you are gaining by bringing the crystal filter in later; I'll do if there's something to be gained, it sounds an interesting approach. David G3UNA A couple of related points, which may not be new news to anyone: You can set the K3's filter bandwidth configuration to cause the roofing filter to switch at points other than the bandwidth printed on the filter. Maybe you would like your (nominally) 500 Hz filter to switch in at 450 or 550 Hz. My 8-pole 250 Hz filter is a bit broader than 250 Hz, and I've set it to switch at 300 Hz. You can also turn off a filter (set its bandwidth to zero temporarily) to evaluate whether a change you're hearing is due to the roofing filter or the change in bandwidth provided by the DSP. And you should attempt to adjust the filter gain compensation so that there is no change in the volume of the note you're tuned to. Rene, who guides the assembly of K3s built by Elecraft, told me that he uses a voltmeter on the speaker terminals when adjusting the gain compensation and can get usually get within a half decibel. I notice a definite qualitative change as the narrower filters switch in. It sounds quieter, and it seems like the volume is being turned down. I think I'm responding to the reduced low and high frequency components that are supposed to be cut off. The DSP-related changes seem more gradual. Dick, K6KR ___ 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: Re: [Elecraft] Hearing the effect of narrower roofing filter
Nope, I have not. My operating (near zero right now due to life getting in the way) is 99.9% CW, old school, with manual keys. I'm not pushing the envelop so I'm not trying new novel things. These days, I pretty much just use my rig rather than playing testing with it. - Keith N1AS - - K3 711 - -Original Message- Have you de-selected the roofing filters to do a comparison with and without? ___ 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: Re: [Elecraft] Hearing the effect of narrower roofing filter
I'm not completely sure what to do with this capability, other than perhaps have the switchover occur at a bandwidth that more closely matches the filter you actually have. What I've done is tell the K3 that my 250 Hz filter is really 300 Hz (it's really probably more like 370 Hz). I also have a 400 Hz filter. I didn't make a particularly wise choice of filter bandwidths. To those who have pointed out the error of my ways, my defense is that I chose the filters on first order day before the curves were published on the web site. I don't view this as a severe issue. Maybe I should have ordered the 200 Hz 5-pole instead, but I got it into my head that maybe the 8-pole filters were better in some way. I didn't repeat this mistake when I ordered filters for the subreceiver. Dick, K6KR -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of David Cutter Sent: Tuesday, July 08, 2008 10:18 AM To: elecraft@mailman.qth.net Subject: Re: Re: [Elecraft] Hearing the effect of narrower roofing filter But if you leave the setting at its nominal, can you hear the difference as that bandwidth is selected? I'm not sure I understand the advantage you are gaining by bringing the crystal filter in later; I'll do if there's something to be gained, it sounds an interesting approach. David G3UNA A couple of related points, which may not be new news to anyone: You can set the K3's filter bandwidth configuration to cause the roofing filter to switch at points other than the bandwidth printed on the filter. Maybe you would like your (nominally) 500 Hz filter to switch in at 450 or 550 Hz. My 8-pole 250 Hz filter is a bit broader than 250 Hz, and I've set it to switch at 300 Hz. You can also turn off a filter (set its bandwidth to zero temporarily) to evaluate whether a change you're hearing is due to the roofing filter or the change in bandwidth provided by the DSP. And you should attempt to adjust the filter gain compensation so that there is no change in the volume of the note you're tuned to. Rene, who guides the assembly of K3s built by Elecraft, told me that he uses a voltmeter on the speaker terminals when adjusting the gain compensation and can get usually get within a half decibel. I notice a definite qualitative change as the narrower filters switch in. It sounds quieter, and it seems like the volume is being turned down. I think I'm responding to the reduced low and high frequency components that are supposed to be cut off. The DSP-related changes seem more gradual. Dick, K6KR ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.138 / Virus Database: 270.4.6/1540 - Release Date: 7/8/2008 6:33 AM No virus found in this incoming message. Checked by AVG - http://www.avg.com Version: 8.0.138 / Virus Database: 270.4.6/1540 - Release Date: 7/8/2008 6:33 AM ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
