k7iou
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« on: May 03, 2014, 08:30:32 AM » |
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Does anyone have the complete article ? I found one online but it stops mid sentence on page 5. Amplified Elliptic Low Pass Audio Filters simplified and approved Dallas Lankford 5/29/06 rev. 5/26/08 http://docs4.chomikuj.pl/1992242688,PL,0,0,ELPAFs.pdf73 de k7iou
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Patrick J. / KD5OEI
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« Reply #1 on: May 03, 2014, 09:25:39 AM » |
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there is a yahoo group here that might have it. http://www.kongsfjord.no/dl.htm
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Radio Candelstein - Flagship Station of the NRK Radio Network.
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k7iou
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« Reply #2 on: May 03, 2014, 09:49:54 AM » |
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Thanks, I sent an email out to the group. I checked out the group before but was disappointed that nothing is posted there, files etc. de k7iou
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pa0ast
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« Reply #3 on: May 03, 2014, 12:33:55 PM » |
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Elsie is a programm to calculate LC filters . The student version is free... See http://tonnesoftware.com/elsie.htmlInteresting nice programm , works OK. The input and output impedance is very important. I use differential mains coils of 2x 50mH and put the coils in serie to get a 200mH coil for less then a dollar. Adjusting is possible to add windings by drilling a hole in the center and ad the wire though it. Perfect for designing lowpass audio filters. I measured some designs and if properly loaded the figures are as calculated. see photo. a steep 3.5 kHz loww pass filter at 7kC 60 dB down 4kOhm in and output imp. With small coil values the in and output imp is quite high. With big coils You can go low f.i. 200 Ohm or so. Anton
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k7iou
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« Reply #4 on: May 03, 2014, 08:14:38 PM » |
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I joined but no messages are allowed except by a moderator. There are no files posted. I don't understand why the group exists? ? Seems worthless as a group to me. My messages were returned, to < thedallasfiles2@yahoogroups.com>. Your message was not delivered because it was sent to an announcement-only group, where only the moderator may post. A copy of your original message is attached.
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Patrick J. / KD5OEI
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« Reply #5 on: May 03, 2014, 08:31:00 PM » |
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That's kind of silly. Maybe it is a cobweb, squatter, or placeholder.
I was very happy with Elsie as well as with Linear's program.
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Radio Candelstein - Flagship Station of the NRK Radio Network.
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k7iou
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« Reply #6 on: May 03, 2014, 09:00:38 PM » |
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Getting off topic Please keep it to the original post and question.
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KA0HCP
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« Reply #7 on: May 03, 2014, 09:13:01 PM » |
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It seems appropriate to discuss where to find Dallas Lankford information, since that IS the original topic.
From what I've been able to gather Mr. Lankford pulled his work from the internet a few years ago and moved it to a limited access Yahoo discussion group. I had tried to access that group a couple years ago without success.
Apparently during the Yahoo discussion group reorganization a year or so ago, the files were lost, leaving Lankford to rebuild...
I'm not sure what drove him to remove his works from public access. It's quite unfortunate considering how prolific he was, and that he originally was inspired to share his knowledge. b.
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New callsign KA0HCP, ex-KB4QAA. Relocated to Kansas in April 2019.
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k7iou
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« Reply #8 on: May 03, 2014, 09:24:12 PM » |
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It seems appropriate to discuss where to find Dallas Lankford information, since that IS the original topic.
Elsie software is not the topic I posted.
From what I've been able to gather Mr. Lankford pulled his work from the internet a few years ago and moved it to a limited access Yahoo discussion group. I had tried to access that group a couple years ago without success.
Apparently during the Yahoo discussion group reorganization a year or so ago, the files were lost, leaving Lankford to rebuild...
I'm not sure what drove him to remove his works from public access. It's quite unfortunate considering how prolific he was, and that he originally was inspired to share his knowledge. b.
I wondered what happened to his work. Now I know and I agree with you about his work.
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k7iou
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« Reply #9 on: May 03, 2014, 09:30:30 PM » |
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SquatterThat's kind of silly. Maybe it is a cobweb, squatter, or placeholder.
I was very happy with Elsie as well as with Linear's program.
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w3jn
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« Reply #11 on: May 03, 2014, 11:32:38 PM » |
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Getting off topic Please keep it to the original post and question.
It most certainly is on topic and a good contribution to the thread. Please resist the temptation to backseat moderate.
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FCC: "The record is devoid of a demonstrated nexus between Morse code proficiency and on-the-air conduct."
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nq5t
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« Reply #13 on: May 04, 2014, 10:26:43 AM » |
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I'd forgotten about web.archive. Went looking, and even found the ancient ham radio site (globeking.com) I took down many years ago. It was fun to see some of those old pics Grant NQ5T
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