[Elecraft] Shack cleaning sale
I have a couple kits I just don't have time to build. Please contact me offline if interested. All include shipping (in US). BLT Tuner - unbuilt - $ 45 -- Still Available Amtel AVR kit from 2004 Buildathon (includes optional quick release socket) and all parts from session including display) - built and tested - $45 -- Still Available Pete WK8S ___ 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] Re: K2 SSB mic input frequency response
Fran, My K2/100 S/N 04031 KSB2 board is stock except for the filter width which is 2.5 kc. I use the Elecraft (Heil) MD 2 microphone. On the air reports I receive would indicate that my audio is excellent. Adjusting the filters in my opinion is the most important part of getting good audio response. My 2 cents worth. 73, Bob VE3XM ___ 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] ELECRAFT'S REPAIR SERVICE FIVE STARS
Hello all, Late last year, I had my K2 (QRP with all options) serviced by one of the popular list members. I really wasnt satisfied with the results and recently sent the rig to Elecraft for a good going over. Elecrafts results were remarkable. 19itemswere corrected/repaired/checked or modified. Some items were corrected that I never realized were a problem. One example. The KNB2 never really worked since I built it in 2003. Elecraft replaced two diodes, repairing the KNB2. They also got all four filters in perfect tone alignment. Gary provided a detailed list of all that was done and the time it took. Bottom line is, send it to the people who know the rig best, the designers. To be fair, the list member I sent it to offered to refund my money. Ken, W2GIW, Oaklyn, NJ K2 S/N 3,614 K1 S/N 1,329 ___ 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] KIO2 not working
Please continue to keep this one live on the reflector as I am also having problems with mine and will use your findings to help me. Bill K9YEQ K2-#35 KX1-#35 -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of James Kern Sent: Friday, August 26, 2005 10:09 AM To: 'tom.w3qs' Cc: 'Elecraft' Subject: RE: RE: [Elecraft] KIO2 not working Tom, Here at work I tried the cable with and without the jumper - no difference. I confirmed the 5th step on page 11. It is indeed set for U8-4 instead of U6-25. I also tried it here at work on another machine. It's a pIII something or other. It's a desktop PC. It has two serial ports. I verified all the port setings in device manager matches what is called for in the manual - no dice. We use this machine all the time to connect hyperterminal to routers and such, so I know the port is good. I double checked the voltages on the KIO2 and everything looks as it should... I'm pretty confused.. James Kern KB2FCV -Original Message- From: tom.w3qs [mailto:[EMAIL PROTECTED] Sent: Friday, August 26, 2005 11:02 AM To: [EMAIL PROTECTED] Subject: RE: RE: [Elecraft] KIO2 not working Well James, About the jumper, I doubt if it's your problem. I put the jumper in and have tried several programs and have no issues with it. I don't, however, key the transmitter from the keyboard. Of course you could always lift one side and check. You should also confirm that the 5th step on page 11 results in seeing U8-4 instead of U6-25. Somehow mine got switched back to U6-25 and nothing worked until I changed it back. At this point, I would definitely suspect your laptop. How old is it? The last laptop I bought in 1999 didn't have a serial port. Are you using a USB emulator? Tom -Original Message- From: James Kern [mailto:[EMAIL PROTECTED] Sent: Friday, August 26, 2005 8:53 AM To: 'tom.w3qs' Cc: 'Elecraft' Subject: RE: RE: [Elecraft] KIO2 not working Yeah everything at least appears to be ok on the K2. The voltages seem to line up relatively close. I'm not sure if pin 2 of J1 is supposed to change from -9 volts to +13 volts when anything is changed on the k2 (frequency, mode, etc).. But it appears to be doing something. My only bit of confusion is whether having the jumper on pin 7 8 of the PC side serial cable connector has anything to do with my problem? James Kern Network Administrator Kurt S. Adler, Inc. 1107 Broadway New York, NY 10010 212-924-0900 x222 (work) 212-807-0575 (fax) 908-451-6801 (cell) 800-209-7438 (pager) [EMAIL PROTECTED] -Original Message- From: tom.w3qs [mailto:[EMAIL PROTECTED] Sent: Friday, August 26, 2005 7:36 AM To: [EMAIL PROTECTED] Subject: RE: RE: [Elecraft] KIO2 not working Hi James, If everything on the K2 side is OK and you wired up the serial cable correctly, the problem pretty much has to be in your laptop. First, check Device Manager to see if you have any COM ports listed (it's not enough to just have a physical serial connector on the laptop). While you are there, if any are listed, make a note of the numbers - probably 1. Then in the set up for whatever program you are using, make sure that that number is selected. Hope the simple approach works. Tom, W3QS -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of [EMAIL PROTECTED] Sent: Thursday, August 25, 2005 11:11 PM To: [EMAIL PROTECTED] Cc: 'Elecraft' Subject: Re: RE: [Elecraft] KIO2 not working Alright, I got the choke installed and I now get voltage out to the pins. I still cannot connect with my laptop, but I'm going to bring the K2 into work tommorrow. The voltages I get on J1 are as follows: Pin 1: 0 Pin 2: -9.96 or 13.68 (It changes as I move the dial or change anything on the K2) Pin 3: .01 Pin 4: 5.59 Pin 5: 0 Pin 6: 5.71 Pin 7: 0.01 Pin 8: 14.24 Pin 9: 8.07 I had a 14V Supply in the K2 and had nothing connected to the J1. I can still hear the oscillation at 16.292 mhz. I did install the jumper between pins 7 and 8 on the PC side of the serial connector if that makes any difference. Do I have to change anything on the computer for that? I see this choice was optional.. Thanks, James KB2FCV - Original Message - From: James Kern [EMAIL PROTECTED] Date: Thursday, August 25, 2005 3:42 pm Subject: RE: [Elecraft] KIO2 not working Well the replacement choke arrived here at the office today. I'll post an update when I get home tonight (The soldering iron will be warming up the second I walk through the door!.. Alright.. Well, after I say hello to my wife!) James Kern Network Administrator Kurt S. Adler, Inc. 1107 Broadway New York, NY 10010 212-924-0900 x222 (work) 212-807-0575 (fax) 908-451-6801 (cell) 800-209-7438 (pager) [EMAIL PROTECTED] -Original Message- From: Tom Hammond [mailto:[EMAIL PROTECTED] Sent: Thursday, August 18, 2005 7:28 AM To: [EMAIL PROTECTED] Subject: Re: [Elecraft] KIO2 not
[Elecraft] MY SECOND K2
Well I have ordered a second k2. my first k2 got hit with lightning so now I get to repair the first but the insurance is paying for another cause I don't know if the first is repairable. But I do get to have the fun of building a second k2. see ya 73's N1IB David Schornak K2 03027 K2 0 www.n1ib.com www.n1ib.com/blog/ www.n1ib.com/leather/ arf don't forget me Mis Ginger ___ 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] MY SECOND K2
Well I have ordered a second k2. my first k2 got hit with lightning so now I get to repair the first but the insurance is paying for another cause I don't know if the first is repairable. I'm curious if insurance covered any cost of building or did they just cover the cost of the kit? Was it your homeowners insurance or special coverage on your radios? Craig NZ0R K1 #1966 K2/100 #4941 ___ 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] MY SECOND K2
That's what started it all - the silver lining is one heck of a good conductor... :-) Mike AB3AP On Mon 29-Aug-05 at 1005 EDT, James Kern wrote: Every cloud has it's silver lining - have fun building that second K2! 73, James Kern KB2FCV -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of David Sent: Monday, August 29, 2005 10:01 AM To: 'K. J.'; elecraft@mailman.qth.net Subject: [Elecraft] MY SECOND K2 Well I have ordered a second k2. my first k2 got hit with lightning so now I get to repair the first but the insurance is paying for another cause I don't know if the first is repairable. But I do get to have the fun of building a second k2. see ya 73's N1IB David Schornak K2 03027 K2 0 www.n1ib.com www.n1ib.com/blog/ www.n1ib.com/leather/ arf don't forget me Mis Ginger ___ 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] MY SECOND K2
I was told by my agent that they would have covered the my labor if I had asked for it but I did not because it was just to much fun to build and they are letting me the damaged equipment and I think I can rebuild the first k2 and get it working a hundred percent. It is all covered by my home owners insurance -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Craig Rairdin Sent: Monday, August 29, 2005 10:15 AM To: elecraft@mailman.qth.net Subject: RE: [Elecraft] MY SECOND K2 Well I have ordered a second k2. my first k2 got hit with lightning so now I get to repair the first but the insurance is paying for another cause I don't know if the first is repairable. I'm curious if insurance covered any cost of building or did they just cover the cost of the kit? Was it your homeowners insurance or special coverage on your radios? Craig NZ0R K1 #1966 K2/100 #4941 ___ 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: [Elecraft] KIO2 not working
Bill Johnson wrote: Please continue to keep this one live on the reflector as I am also having problems with mine and will use your findings to help me. Bill K9YEQ Do you folks have the rs-232 port turned on via the menu? I use the rs-232 all the time, and this got me once. tom bosscher K8TB K2-3206 K2-5050 ___ 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] MY SECOND K2
You are probably correct but why was lightening allowed to enter this chap's first K2. Was that the only good reason he could think of to tell his yl that he needed to build another one? Just wondering. Remember inquiring minds need to know. LOL! Paul Paul Gates K1 #0231 KX1 #1186 XG1 [EMAIL PROTECTED] Original Message Follows From: James Kern [EMAIL PROTECTED] Reply-To: [EMAIL PROTECTED] To: 'David' [EMAIL PROTECTED], 'K. J.' [EMAIL PROTECTED],elecraft@mailman.qth.net Subject: RE: [Elecraft] MY SECOND K2 Date: Mon, 29 Aug 2005 10:05:32 -0400 Every cloud has it's silver lining - have fun building that second K2! 73, James Kern KB2FCV -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of David Sent: Monday, August 29, 2005 10:01 AM To: 'K. J.'; elecraft@mailman.qth.net Subject: [Elecraft] MY SECOND K2 Well I have ordered a second k2. my first k2 got hit with lightning so now I get to repair the first but the insurance is paying for another cause I don't know if the first is repairable. But I do get to have the fun of building a second k2. see ya 73's N1IB David Schornak K2 03027 K2 0 www.n1ib.com www.n1ib.com/blog/ www.n1ib.com/leather/ arf don't forget me Mis Ginger ___ 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 ___ 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] MY SECOND K2
Okay radios where turned off Antennas where disconnected and the house next door took the direct hit and blew a big chunk out of the back of the house. It appears that the blast came in through my astron rs35 which was toasted by the strike. And I don't have a yl to tell. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Paul Gates Sent: Monday, August 29, 2005 11:03 AM To: [EMAIL PROTECTED] Cc: elecraft@mailman.qth.net Subject: RE: [Elecraft] MY SECOND K2 You are probably correct but why was lightening allowed to enter this chap's first K2. Was that the only good reason he could think of to tell his yl that he needed to build another one? Just wondering. Remember inquiring minds need to know. LOL! Paul Paul Gates K1 #0231 KX1 #1186 XG1 [EMAIL PROTECTED] Original Message Follows From: James Kern [EMAIL PROTECTED] Reply-To: [EMAIL PROTECTED] To: 'David' [EMAIL PROTECTED], 'K. J.' [EMAIL PROTECTED],elecraft@mailman.qth.net Subject: RE: [Elecraft] MY SECOND K2 Date: Mon, 29 Aug 2005 10:05:32 -0400 Every cloud has it's silver lining - have fun building that second K2! 73, James Kern KB2FCV -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of David Sent: Monday, August 29, 2005 10:01 AM To: 'K. J.'; elecraft@mailman.qth.net Subject: [Elecraft] MY SECOND K2 Well I have ordered a second k2. my first k2 got hit with lightning so now I get to repair the first but the insurance is paying for another cause I don't know if the first is repairable. But I do get to have the fun of building a second k2. see ya 73's N1IB David Schornak K2 03027 K2 0 www.n1ib.com www.n1ib.com/blog/ www.n1ib.com/leather/ arf don't forget me Mis Ginger ___ 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 ___ 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: [Elecraft] MY SECOND K2
Mercy, Mercy That is terrible And also sorry about no YL! g Paul Gates K1 #0231 KX1 #1186 XG1 [EMAIL PROTECTED] Original Message Follows From: David [EMAIL PROTECTED] To: 'Paul Gates' [EMAIL PROTECTED],[EMAIL PROTECTED] CC: elecraft@mailman.qth.net Subject: RE: [Elecraft] MY SECOND K2 Date: Mon, 29 Aug 2005 11:17:53 -0400 Okay radios where turned off Antennas where disconnected and the house next door took the direct hit and blew a big chunk out of the back of the house. It appears that the blast came in through my astron rs35 which was toasted by the strike. And I don't have a yl to tell. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Paul Gates Sent: Monday, August 29, 2005 11:03 AM To: [EMAIL PROTECTED] Cc: elecraft@mailman.qth.net Subject: RE: [Elecraft] MY SECOND K2 You are probably correct but why was lightening allowed to enter this chap's first K2. Was that the only good reason he could think of to tell his yl that he needed to build another one? Just wondering. Remember inquiring minds need to know. LOL! Paul Paul Gates K1 #0231 KX1 #1186 XG1 [EMAIL PROTECTED] Original Message Follows From: James Kern [EMAIL PROTECTED] Reply-To: [EMAIL PROTECTED] To: 'David' [EMAIL PROTECTED], 'K. J.' [EMAIL PROTECTED],elecraft@mailman.qth.net Subject: RE: [Elecraft] MY SECOND K2 Date: Mon, 29 Aug 2005 10:05:32 -0400 Every cloud has it's silver lining - have fun building that second K2! 73, James Kern KB2FCV -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of David Sent: Monday, August 29, 2005 10:01 AM To: 'K. J.'; elecraft@mailman.qth.net Subject: [Elecraft] MY SECOND K2 Well I have ordered a second k2. my first k2 got hit with lightning so now I get to repair the first but the insurance is paying for another cause I don't know if the first is repairable. But I do get to have the fun of building a second k2. see ya 73's N1IB David Schornak K2 03027 K2 0 www.n1ib.com www.n1ib.com/blog/ www.n1ib.com/leather/ arf don't forget me Mis Ginger ___ 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 ___ 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
[Elecraft] MFJ HI-Q Loop 1788 Will not stay on frequency.
I do a lot of camping and have used several portable antennas over the years. Two weeks ago I bought a MFJ-1788 Super HI-Q Loop. I have been on two camping trips with it and it does seem to get out and receive well. I used my K2/100 and made 46 contacts for a total of almost 15 hours of operating time. My problem is the antenna will not stay on frequency. It will tune on any frequency easily but the only time it will stay on frequency is in the middle of the night with no wind. I talked to MFJ and Tom recommended I tighten the spring on the capacitor. I did and it improved but again this week end I saw it jump and drift. I had it tuned up on 14.058 and it dropped down to 14.007. Another time it jumped from 14.058 to 14.076. I know others are using this antenna so if you are using it do you have a problem with it jumping or drifting around in the band. I have noticed this problem on every band except during a cold, clear, calm night. If anyone has been able to fix this problem or if my problem is not normal please let me know. 73 and thank you. Ken W0CA [EMAIL PROTECTED] K2/100 sn 1031 ___ 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] K2 Optimizations?
Thanks to all who emailed me. Just to clarify, I will not be replacing any of the Elecraft supplied parts. From what I have read Elecraft goes to great lengths to ensure high quality components and subsituting those parts with my own would be a recipe for disaster. I also will not deviate from the values specified. As I look at the K2 schematics it seems there would be places where matching components would be of benefit. For example R12 on the Front Panel board should be as close to the resistances of RP2 as possible to have even brightness on the LED array. Since there are five 120 ohm resistors supplied with the K2, why not pick the one that is closest to the average resistance of RP2 or even the adjacent segment resistor RP2 pins 1 and 10. The same with R53 and R54 on the RF board. There are four 4.7 ohm resistors supplied with the kit, so why not pick the two that are closest to each other in resistance? There are obvious places where matching would seem to be of some benefit, however small, but I am wondering about the less obvious. Since my knowledge of electronics is somewhat limited, and I don't understand what some components purposes are in some circuits, I was hoping that others would help me feed my insanity by suggesting other possible but less obvious components to match. I will not hold anyone responsible for any psychiatrist bills. :-) Along this same line, is it possible to match varactor diodes? There are eleven 1SV149 varactor diodes supplied with the kit. Matching D29 to D34 in the CW IF filter would perhaps be of some value. Then again I look at the pair of varactor diodes D21 and D22 in the VFO circuit and I wonder if they should be matched? It would also seem that the combination of D23, D24, D25 and D26 are grouped to provide more capacitance swing (Am I right?) and may benefit from diodes that are closer to the edge of their component tolerance. Yes? Yes, I know that I am bordering on insanity, but hey I want to really take my time and stretch out the building. Besides the more I learn about my K2 in the process the better. On August 28, 2005 04:25 pm, Darrell Bellerive wrote: I'm about to build my second K2. Stupid me, sold the first one. But then again I really like building. Being a perfectionist to the nth degree and an optimization freak, I am wondering about component tolerance and matching components. While I realize that with the components supplied and following the manual instructions will result in a rig that meets all specification, I can't help but wonder if I can't get that last little bit of perfection by selecting the best component for the job. I measure each resistor and capacitor before mounting them on the circuit boards just to confirm my correct reading of color bands or values. So if I have more than one of a certain value component, and if they have slightly different values, yet still within the tolerance, then perhaps a particular value will work better in one part of the circuit than another. Perhaps even some parts of the circuitry will benefit a tiny bit from matched components. Yes, I know that this is taking things to the extreme, but that is my perfectionist nature shining through. So, can anyone think of any circuits of the K2 that would benefit in even the slightest way by hand picking a component that is right on it's value vs. one that is near the upper or lower tolerance, or visa versa? 73, Darrell -- Darrell Bellerive Amateur Radio Stations VA7TO and VE7CLA Grand Forks, British Columbia, Canada ___ 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] Measuring Inductance with the MFJ-259
Thanks to all who responded. I had no plans of deviating from the number of turns that Elecraft directs. I will follow their instructions as to the best of my ability. I have learned a few things: 1) Adjusting the spacing of the winding on the toroids does not change the inductance, just the distributed capacitance of the toroid. 2) The values specified by Elecraft are dependant on their measurement equipment and techniques, and my measurement equipment and techniques probably wouldn't show the same values. So it is not worth the trouble of trying to measure them. 3) Don't bother with Q-Dope or any other method of attaching the windings to the cores as friction is sufficient even in mobile applications. On August 28, 2005 04:31 pm, Darrell Bellerive wrote: As I build my second K2, I want to try to measure the inductance of the toroids with my MFJ-259. The MFJ manual has instructions on how to do this. Essentially one builds a series LC circuit and measures the resonant frequency and then calculates the inductance. Has anyone tried this and have any tips or tricks to pass on? Am I correct in assuming I can adjust the value of inductance on a toroid slightly by compressing or expanding the spacing between turns? If so what can I use to hold the turns in place. Friction is probably good enough, but I wonder about a few drops of something like Q-Dope. Comments? 73, Darrell -- Darrell Bellerive Amateur Radio Stations VA7TO and VE7CLA Grand Forks, British Columbia, Canada ___ 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] Measuring Inductance with the MFJ-259
The Elecraft designers have stated in past discussions that Coil Dope is not needed if you wind your toroids tight. Remember, that the dielectric constant of Coil Dope can change your tuning of the coil. It would be alright to use a few drops on ends of winding as an aid, but a lot could be a problem. Stuart K5KVH ___ 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] For Sale K2
Late serial K2 with most accessories for sale at Elecraft prices. Perfect condition electrically and physically Telephone for full information 9a to 9p Pacific 360 638 2707 73 Earl W7TK ___ 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] Measuring Inductance with the MFJ-259
Hello Darrell, The inductance of the toroids typically used in the K2 can be increased by compressing the turns. This can be done to fine-tune a circuit but for consistent results, it's probably best to do it the way the Elecraft guys recommend and spread out the turns a bit. I've evaluated a toroid, L5, in the KAT2 with both close spacing and loose spacing. The data can be seen here: http://w5big.home.comcast.net/L5Analysis.htm 73/ Bob - W5BIG - Original Message - From: Darrell Bellerive [EMAIL PROTECTED] To: elecraft@mailman.qth.net Sent: Sunday, August 28, 2005 6:31 PM Subject: [Elecraft] Measuring Inductance with the MFJ-259 As I build my second K2, I want to try to measure the inductance of the toroids with my MFJ-259. The MFJ manual has instructions on how to do this. Essentially one builds a series LC circuit and measures the resonant frequency and then calculates the inductance. Has anyone tried this and have any tips or tricks to pass on? Am I correct in assuming I can adjust the value of inductance on a toroid slightly by compressing or expanding the spacing between turns? If so what can I use to hold the turns in place. Friction is probably good enough, but I wonder about a few drops of something like Q-Dope. Comments? ___ 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] KIO2 not working
Oh, Yes... been there done all of that. I have tried a number of things. Will probably just order a new one. And then fix the old one and sell it. Bill K9YEQ K2-#35 KX1-#35 -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Tom Bosscher Sent: Monday, August 29, 2005 11:01 AM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] KIO2 not working Bill Johnson wrote: Please continue to keep this one live on the reflector as I am also having problems with mine and will use your findings to help me. Bill K9YEQ Do you folks have the rs-232 port turned on via the menu? I use the rs-232 all the time, and this got me once. tom bosscher K8TB K2-3206 K2-5050 ___ 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
[Elecraft] OT: Effect of Compression and Expansion on the Inductance of Toroids?
Well, it seems now that I am receiving contradictory information. Specifically that compressing the turns on a toroid will raise the inductance. What is the real scoop. Does compressing or expanding the spacing of the winding on a toroid change the inductance? Or just the distributed capacitance of the toroid? Or is this much more complex than I would have expected? On August 29, 2005 10:40 am, Darrell Bellerive wrote: I have learned a few things: 1) Adjusting the spacing of the winding on the toroids does not change the inductance, just the distributed capacitance of the toroid. -- Darrell Bellerive Amateur Radio Stations VA7TO and VE7CLA Grand Forks, British Columbia, Canada ___ 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] Don't forget Elecraft email Tech Support!
Don't forget that Elecraft Technical Support is always only an email away. When you have a question that can't be answered on the Elecraft list or are stumped troubleshooting a problem, make sure to contact our experienced engineers at [EMAIL PROTECTED] :-) Gary, Scott, Brian and Richard are experts on Elecraft products with thousands of hours of experience between them. They have seen almost every possible problem and will steer you in the right direction quickly. We're here to help! Elecraft Support: The 'Bug Busters' 73, Eric WA6HHQ Elecraft Bill Johnson wrote: Oh, Yes... been there done all of that. I have tried a number of things. Will probably just order a new one. And then fix the old one and sell it. Bill K9YEQ -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Tom Bosscher Sent: Monday, August 29, 2005 11:01 AM To: elecraft@mailman.qth.net Subject: Re: [Elecraft] KIO2 not working Bill Johnson wrote: Please continue to keep this one live on the reflector as I am also having problems with mine and will use your findings to help me. Bill K9YEQ Do you folks have the rs-232 port turned on via the menu? I use the rs-232 all the time, and this got me once. tom bosscher K8TB ___ 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] OT: Effect of Compression and Expansion on the Inductance of Toroids?
The toroid formulas are approximations, but good ones. Here is a physics-based explanation that gives some of the complexities, but there are literally books on inductors. http://tinyurl.com/9brxb Leigh / WA5ZNU On Mon, 29 Aug 2005 3:52 pm, Darrell Bellerive wrote: Well, it seems now that I am receiving contradictory information. Specifically that compressing the turns on a toroid will raise the inductance. What is the real scoop. Does compressing or expanding the spacing of the winding on a toroid change the inductance? Or just the distributed capacitance of the toroid? Or is this much more complex than I would have expected? ___ 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] OT: Effect of Compression and Expansion on theInductance of Toroids?
Darrell, There may be a small apparent change in inductance when adjusting the turns spacing of a toroid, but it would only be a small percentage - look at the formulas for a toroid inductor to verify that fact - there is no term for the turns spacing, and the diameter of the toroid fixes the coil length. Check out http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/indtor.html for the detailed formulas. If you move all the turns to one side of the toroid core, it may begin to behave more like a solenoidal inductor and the inductance could possibly change because the effective length of the solenoidal inductor will change, but I have not persued that 'angle'. Elecraft usually specifies that the winding should occupy about 85% of the core, so that 'fixes' the length of the coil question for a properly wound Elecraft toroid. The inter-turn capacity is bound to change with the turns spacing, and that may show up as an apparent change in 'inductance' on many meters because they do measure inductance at a specific frequency. The best way I can think of to prove or disprove it would be to measure the time constant in an LR series circuit. 73, Don W3FPR -Original Message- Well, it seems now that I am receiving contradictory information. Specifically that compressing the turns on a toroid will raise the inductance. What is the real scoop. Does compressing or expanding the spacing of the winding on a toroid change the inductance? Or just the distributed capacitance of the toroid? Or is this much more complex than I would have expected? -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.344 / Virus Database: 267.10.16/83 - Release Date: 8/26/2005 ___ 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] MY SECOND K2
On Aug 29, 2005, at 11:17 AM, David wrote: Antennas where disconnected and the house next door took the direct hit and blew a big chunk out of the back of the house. Don't just disconnect your antennas - GROUND them. Possibly would have saved your rig. Bill Coleman, AA4LR, PP-ASELMail: [EMAIL PROTECTED] Quote: Not within a thousand years will man ever fly! -- Wilbur Wright, 1901 ___ 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] ECN errata
Two errors in last night's report. Russ - N9IV - was running his K2 at near QRP levels. I knew it was low power so took a chance on it being his KX1. Whoops! The next error was for: Ken - N5EBD - running a vintage K1-40/20 with S/N - 34. Now that his rig is getting broken in it is doing yeoman duty for him. Welcome to ECN Ken! Not an error but an addition: Dick - W0NTA - was running in eclectic mode last night. Elecraft Net, Yaesu hat, Icom radio, and a roof mounted SteppIR antenna all from his mountain get a way. Tough life Dick! I am glad your antenna projects are doing well. Until we meet again next Sunday, Kevin. KD5ONS (Error Prone Net Op) -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.344 / Virus Database: 267.10.17/84 - Release Date: 8/29/2005 ___ 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] OT: Effect of Compression and Expansion ontheInductance of Toroids?
Okay, this is interesting so I approached an answer in my usual way. I grabbed a loose toroidal inductor that had nicely spaced turns filling 90% of the circumference of the core and stuck it in my L-meter. 3.1 uH. Scrunched all the turns tightly together. They filled about 20% of the circumference. Inductance now 3.3 uH. The L-meter uses a low frequency signal so capacitance shouldn't make much difference in the reading. So fully spaced to totally scrunched, in this case, yielded a 9% change in inductance. It's nice to work the numbers, but I've always tended toward a direct experiment whenever possible. Back in school, I always knew where my soldering iron was but was forever forgetting where I had put my slide rule. I haven't changed. (For the newer readers, a slide rule is the ancestor of the pocket calculator. For comparison, a slide rule is to a calculator as working CW on 40 meters is to making a cell phone call.) Ron AC7AC ___ 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] OT: Effect of Compression and ExpansionontheInductance of Toroids?
I don't have your experience or background, Ron, but the L-meter is measuring inductance indirectly and ignoring the presence of distributed capacitance. Maybe it isn't as negligible at the frequency of the meter as you think. But in the end, it doesn't really matter. The real test is how a particular toroid reacts in the circuit it was intended for. If adjusting the turns spacing changes circuit resonance, then...it changes circuit resonance. That's the result we would have been looking for. Hi. Eric KE6US www.ke6us.com -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Ron D'Eau Claire Sent: Monday, August 29, 2005 5:29 PM To: [EMAIL PROTECTED]; [EMAIL PROTECTED]; elecraft@mailman.qth.net Subject: RE: [Elecraft] OT: Effect of Compression and ExpansionontheInductance of Toroids? Okay, this is interesting so I approached an answer in my usual way. I grabbed a loose toroidal inductor that had nicely spaced turns filling 90% of the circumference of the core and stuck it in my L-meter. 3.1 uH. Scrunched all the turns tightly together. They filled about 20% of the circumference. Inductance now 3.3 uH. The L-meter uses a low frequency signal so capacitance shouldn't make much difference in the reading. So fully spaced to totally scrunched, in this case, yielded a 9% change in inductance. It's nice to work the numbers, but I've always tended toward a direct experiment whenever possible. Back in school, I always knew where my soldering iron was but was forever forgetting where I had put my slide rule. I haven't changed. (For the newer readers, a slide rule is the ancestor of the pocket calculator. For comparison, a slide rule is to a calculator as working CW on 40 meters is to making a cell phone call.) Ron AC7AC ___ 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: [Elecraft] OT: Effect of Compression and ExpansionontheInductance of Toroids?
Eric, KE6US wrote: I don't have your experience or background, Ron, but the L-meter is measuring inductance indirectly and ignoring the presence of distributed capacitance. Maybe it isn't as negligible at the frequency of the meter as you think. But in the end, it doesn't really matter. The real test is how a particular toroid reacts in the circuit it was intended for. If adjusting the turns spacing changes circuit resonance, then...it changes circuit resonance. That's the result we would have been looking for. Hi. -- I'm fond of saying that the only dumb question is the question not asked, so your question is an excellent one, Eric. As for lots of experience, for me that's too often just an opportunity to remember more things incorrectly. About your question, my L-meter evaluates inductance using a low-frequency square wave at about 60 kHz that goes to a differentiator consisting of a 200 ohm resistor in series with the unknown inductance. The waveform at the junction of the resistor and inductor is a series of spikes at the frequency of the input square wave. The spikes decay at a rate proportional to the time constant of the resistor and inductor. This decay rate is converted into a voltage in a simple logic circuit. The ARRL Handbook has featured this circuit in a number of editions. It's a simple and surprisingly accurate meter, depending upon the quality of the inductors used to calibrate it. The way the circuit works means that any significant capacity in parallel with the inductor would tend to cancel the effect of the inductor, and make the inductance value displayed read lower than it really was, not higher. Again, at the bench I tested that conclusion by adding capacitors in parallel with the inductor. Sure 'nuf, adding capacitance decreased the reading. Recall that squeezing the turns together raised the test inductor value read on the meter from 3.1 to 3.3 uH. Now I added fixed capacitors across the inductor to simulate added distributed capacitance caused by squeezing them together. Adding 10 pf of capacitance across the inductor had zero effect on the reading. Adding 33 pf across the inductor *lowered* the reading by 0.1 uH. We're dealing with a very small toroid in this test whose inter-turn capacitance isn't going to be as much as 2 or 3 pf when squeezed together. So I'm confident that the added capacitance by squeezing the turns together is not what is causing my L-meter to show increased inductance. If anything, the capacitance would tend to cause the L-meter to show lower inductance. Ron AC7AC ___ 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] OT: Effect of Compression and ExpansionontheInductanceof Toroids?
Ron, I have the same inductance meter, and it does a good job because it does measure using the LR time constant rather than frequency, but 'physics is physics', and with a true toroidal inductor, there is still no dependency on the turns spacing (the math says so). Now, for the practical side of things, I do believe that your results (and others with similar findings) deviate from the 'classic physics' treatment of the ideal (ignoring practical behavior) - and when the toroid turns are irregular (not evenly spaced around the circumference of the core), there is some part of that coil behaving as a solenoidal inductor where turns spacing IS a factor. Remember that a toroid is simply a solenoidal coil formed into a circle with the ends of the coil meeting. This ideal toroid has equal turns spacing all the way around. So my current conclusion is -- IF the toroid is equally spaced around the core, the inductance is not dependent on the spacing of the turns, BUT, if the turns are compressed anywhere around the core, additional factors rear their ugly heads because the inductor is a combination of a solenoidal coil and a toroid coil, and the math becomes quite complex - just how much of each effect depends on just how much deviation from an ideal toroid shape exists in the configuration at hand. In a frequency dependent tuned circuit, how much of the frequency shift is due to the inter-turn capacitance or a change in inductance is (to me) only a matter of curiosity - the plain fact is that some change in the resonant frequency (or inductance) can be achieved by changing the turns spacing, but we all know that the adjustment range is small - the really big determining factor is simply the number of turns. As an example, I often improve the 10/12 meter Low Pass Filter characteristics of a KPA100 by squeezing the toroid turns just the right way, but I determine what is the 'right way' by monitoring the impedance with my MFJ259B as I do it. Sometimes it is 'this way', while other times it is 'that way' - the batch to batch change in the permeability of the cores likely accounts for more variation than the turns spacing itself. BTW, this change does not really help the KPA100 output, but it improves the base K2 10 meter efficiency at 10 watts or lower when the KPA100 is installed. The overall inductance change that I have experienced is about 10%, so that is within the normal design tolerances using 10% resistors and capacitors - so except for satisfaction of the curiosity factor, I would say just to wind the toroids with the proper number of turns, and 'tweak' them in-circuit as required and as close as is permitted by your measurement capability. 73, Don W3FPR -Original Message- Eric, KE6US wrote: I don't have your experience or background, Ron, but the L-meter is measuring inductance indirectly and ignoring the presence of distributed capacitance. Maybe it isn't as negligible at the frequency of the meter as you think. But in the end, it doesn't really matter. The real test is how a particular toroid reacts in the circuit it was intended for. If adjusting the turns spacing changes circuit resonance, then...it changes circuit resonance. That's the result we would have been looking for. Hi. -- I'm fond of saying that the only dumb question is the question not asked, so your question is an excellent one, Eric. As for lots of experience, for me that's too often just an opportunity to remember more things incorrectly. About your question, my L-meter evaluates inductance using a low-frequency square wave at about 60 kHz that goes to a differentiator consisting of a 200 ohm resistor in series with the unknown inductance. The waveform at the junction of the resistor and inductor is a series of spikes at the frequency of the input square wave. The spikes decay at a rate proportional to the time constant of the resistor and inductor. This decay rate is converted into a voltage in a simple logic circuit. The ARRL Handbook has featured this circuit in a number of editions. It's a simple and surprisingly accurate meter, depending upon the quality of the inductors used to calibrate it. The way the circuit works means that any significant capacity in parallel with the inductor would tend to cancel the effect of the inductor, and make the inductance value displayed read lower than it really was, not higher. Again, at the bench I tested that conclusion by adding capacitors in parallel with the inductor. Sure 'nuf, adding capacitance decreased the reading. Recall that squeezing the turns together raised the test inductor value read on the meter from 3.1 to 3.3 uH. Now I added fixed capacitors across the inductor to simulate added distributed capacitance caused by squeezing them together. Adding 10 pf of capacitance across the inductor had zero effect on the reading. Adding 33 pf across the inductor *lowered* the reading by 0.1 uH. We're
RE: [Elecraft] OT: Effect of Compression and ExpansionontheInductanceof Toroids?
Yes, I think you may be absolutely right, Don. I measured a maximum effect of 9% in the one example I tested - a random core lying on my bench that had about a dozen turns on it. That agrees with your experience of finding up to a 10% change available. I saw your suggestion before, and it certainly sounds plausible. I wonder if something else might be at work here too. Or perhaps I'm looking the same effect you are in a different way. Here's my thought. The increased inductance/turn of the toroid compared to ordinary air-wound coils is caused by the very high permeability of the core compared to air. That makes the inductance fairly independent of the spacing between turns since spacing the turns hardly reduces the magnetic flux in the core that is available to each turn. But I wonder if crowding the turns together doesn't slightly increase the inductance by providing a lower permeability path for the magnetic flux, since the distance the flux must travel along the toroid before it passes through all the turns of the coil is shorter. In other words, the same effect one sees by using closer spacing in an air wound coil, only much, much less due to the efficient magnetic path provided by the core. Does the formula you are using account for a reduction of flux density around the distance of the torus due to the losses in the core, or does it assume a constant flux at all points? It's always interesting when experiment fails to support predictions. True, it most often turns out to be an invalid experiment that causes that result, but I can't see the problem here, especially considering that the effect of added distributed capacitance has an inverse effect on the reading on this type of 'meter'. Ron AC7AC -Original Message- From: W3FPR - Don Wilhelm [mailto:[EMAIL PROTECTED] Sent: Monday, August 29, 2005 9:22 PM To: Ron D'Eau Claire; elecraft@mailman.qth.net Subject: RE: [Elecraft] OT: Effect of Compression and ExpansionontheInductanceof Toroids? Ron, I have the same inductance meter, and it does a good job because it does measure using the LR time constant rather than frequency, but 'physics is physics', and with a true toroidal inductor, there is still no dependency on the turns spacing (the math says so). Now, for the practical side of things, I do believe that your results (and others with similar findings) deviate from the 'classic physics' treatment of the ideal (ignoring practical behavior) - and when the toroid turns are irregular (not evenly spaced around the circumference of the core), there is some part of that coil behaving as a solenoidal inductor where turns spacing IS a factor. Remember that a toroid is simply a solenoidal coil formed into a circle with the ends of the coil meeting. This ideal toroid has equal turns spacing all the way around. So my current conclusion is -- IF the toroid is equally spaced around the core, the inductance is not dependent on the spacing of the turns, BUT, if the turns are compressed anywhere around the core, additional factors rear their ugly heads because the inductor is a combination of a solenoidal coil and a toroid coil, and the math becomes quite complex - just how much of each effect depends on just how much deviation from an ideal toroid shape exists in the configuration at hand. In a frequency dependent tuned circuit, how much of the frequency shift is due to the inter-turn capacitance or a change in inductance is (to me) only a matter of curiosity - the plain fact is that some change in the resonant frequency (or inductance) can be achieved by changing the turns spacing, but we all know that the adjustment range is small - the really big determining factor is simply the number of turns. As an example, I often improve the 10/12 meter Low Pass Filter characteristics of a KPA100 by squeezing the toroid turns just the right way, but I determine what is the 'right way' by monitoring the impedance with my MFJ259B as I do it. Sometimes it is 'this way', while other times it is 'that way' - the batch to batch change in the permeability of the cores likely accounts for more variation than the turns spacing itself. BTW, this change does not really help the KPA100 output, but it improves the base K2 10 meter efficiency at 10 watts or lower when the KPA100 is installed. The overall inductance change that I have experienced is about 10%, so that is within the normal design tolerances using 10% resistors and capacitors - so except for satisfaction of the curiosity factor, I would say just to wind the toroids with the proper number of turns, and 'tweak' them in-circuit as required and as close as is permitted by your measurement capability. 73, Don W3FPR ___ 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:
