Re: [Elecraft] 75 ohm coax
The same PL-259 reducers for RG-8X works for RG-6. Same for BNC connectors. Bob, K4TAX Sent from my iPhone > On Apr 2, 2020, at 10:13 PM, Ignacy wrote: > > The plus of RG6 is low price, less than 10c a foot. In receive applications, > they seem to be lasting forever. In transmit too but small nuisances are > necessity to use a tuner for low SWR antennas and nonstandard connectors. > But running two in parallel does not make any sense. > > Half a year ago I found Rg6's 50 Ohm equivalent on ebay. Altelix AX240 for > $99/1000ft. Measured parameters same as LMR240. The plus of cheap and good > 1000-ft roll (with crimp connectors that can be attached in 30 sec) is that > the coax can be cut as needed, with no worries about cost. > > Ignacy NO9E > > > > -- > Sent from: http://elecraft.365791.n2.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 > Message delivered to rmcg...@blomand.net > __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] 75 ohm coax
The plus of RG6 is low price, less than 10c a foot. In receive applications, they seem to be lasting forever. In transmit too but small nuisances are necessity to use a tuner for low SWR antennas and nonstandard connectors. But running two in parallel does not make any sense. Half a year ago I found Rg6's 50 Ohm equivalent on ebay. Altelix AX240 for $99/1000ft. Measured parameters same as LMR240. The plus of cheap and good 1000-ft roll (with crimp connectors that can be attached in 30 sec) is that the coax can be cut as needed, with no worries about cost. Ignacy NO9E -- Sent from: http://elecraft.365791.n2.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Transceiver Test Bed at W3LPL
Thanks Bob 73 Frank W3LPL - Original Message - From: "Bob Wilson, N6TV" To: "Elecraft Reflector" Cc: "Frank Donovan, W3LPL" Sent: Thursday, April 2, 2020 9:20:13 PM Subject: Re: [Elecraft] Transceiver Test Bed at W3LPL On Tue, Mar 31, 2020 at 12:50 PM Barry < barrylaz...@gmail.com > wrote: I can't speak to the other radios, but you do need to fiddle the values of the AGC on the K3s to get the best out of the radios. For review, my recommended K3 menu settings and knob position for maximum reduction of receiver "mush" is documented in this post from Feb. 2017, and still applies today: http://elecraft.365791.n2.nabble.com/K3-Receiver-mush-tp7627277p7627323.html 73, Bob, N6TV __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Transceiver Test Bed at W3LPL
On Tue, Mar 31, 2020 at 12:50 PM Barry wrote: > I can't speak to the other radios, but you do need to fiddle the > values of the AGC on the K3s to get the best out of the radios. For review, my recommended K3 menu settings and knob position for maximum reduction of receiver "mush" is documented in this post from Feb. 2017, and still applies today: http://elecraft.365791.n2.nabble.com/K3-Receiver-mush-tp7627277p7627323.html 73, Bob, N6TV __ 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 Message delivered to arch...@mail-archive.com
[Elecraft] Power Issue
When I press the Power button to turn off one of my K3s, the LCD screen stays lit but shows no information. The P3, powered by the 12v outlet at the back of the K3 does go off. Of course, if I turn the power supply off, the LCD screen goes dark. However, when I turn the power supply back on, the rig comes back on also. 73, Ken, K6LA / VY2TT __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] Elecraft K3s - RX OU ANT and Colibrì nano sdr
If all you want to do is create a panadapter, I suggest that you use the IF out of your K3s. I do that and it works nicely. This obviates the need for SDR protection while transmitting. 73 Barry K3NDM On Thu, Apr 2, 2020, 1:52 PM Graziano Roccon (IW2NOY) wrote: > Hello, > > i ordered a Colibrì Nano > (https://eesdr.com/en/products-en/receivers-en/colibrinano-en) > and i am thinkg to connect the Colibrì antenna through the RX ANT OT of > the K3s tu use the colibrì and his software like a panadapter for the > K3s. > The colibrì can't accept "IF OUT", so i will use RX ANT OUT from XV3B to > give antenna signal to the Colibrì. > The Colibrì is one the best SDR (usb) out there with a sample rate of > max 3mhz at 16 bit and 768 khz at 24 bit, the dedicated software > ExpertSDR2 is fantastic anche can used with SDC to have cw skimmer spots > and DX cluster spots on the panadapter. > > > I want to use the Colibrì only like a panadapter and use the K3s to > transmit, syncing the two radio frequncies. > > I would like to know if there are know problem to use this > configuration, especially when i will go in TX with the K3s. > Maybe somebody did it this before me. > There is a protection system that disconnect RX ANT OUT when the K3s go > in TX ? > There is something to configure in the menu ? > Simply, there is a risk for the safeness of the Colibrì connect to the > antenna RX OUT ANT ? > I wouldn't burn the Colibrì with RF or RFI coming from the radio. > > Any help would be appreciated. > > > Thanks a lot, Graziano IW2NOY > __ > 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 > Message delivered to barrylaz...@gmail.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 Message delivered to arch...@mail-archive.com
[Elecraft] Elecraft K3s - RX OU ANT and Colibrì nano sdr
Hello, i ordered a Colibrì Nano (https://eesdr.com/en/products-en/receivers-en/colibrinano-en) and i am thinkg to connect the Colibrì antenna through the RX ANT OT of the K3s tu use the colibrì and his software like a panadapter for the K3s. The colibrì can't accept "IF OUT", so i will use RX ANT OUT from XV3B to give antenna signal to the Colibrì. The Colibrì is one the best SDR (usb) out there with a sample rate of max 3mhz at 16 bit and 768 khz at 24 bit, the dedicated software ExpertSDR2 is fantastic anche can used with SDC to have cw skimmer spots and DX cluster spots on the panadapter. I want to use the Colibrì only like a panadapter and use the K3s to transmit, syncing the two radio frequncies. I would like to know if there are know problem to use this configuration, especially when i will go in TX with the K3s. Maybe somebody did it this before me. There is a protection system that disconnect RX ANT OUT when the K3s go in TX ? There is something to configure in the menu ? Simply, there is a risk for the safeness of the Colibrì connect to the antenna RX OUT ANT ? I wouldn't burn the Colibrì with RF or RFI coming from the radio. Any help would be appreciated. Thanks a lot, Graziano IW2NOY __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] kx3 utility
The magic computer tech fixed it. Thanks for the help. Unplugged the cable and turned all off then turned on and connected cable again and it worked. Thanks to all that replied. Bill WF9M > On April 2, 2020 at 12:07 PM 1lasportsman 1lasportsman <1lasports...@cox.net > mailto:1lasports...@cox.net > wrote: > > > I am using the KXusb cable from computer and acc1 plug on radio but it > does not connect with radio. > Do I need to change the radio speed to 38400 or is it automatic? > If so looked in manual and did not see how > Bill > > > > On April 2, 2020 at 11:54 AM Jack Brindle mailto:jackbrin...@me.com mailto:jackbrin...@me.com mailto:jackbrin...@me.com > > wrote: > > > > > > The utility is telling you that it is communicating with your KX3 > > at 38400 bits/sec. The KX3 has firmware revision 2.90. > > This is not an error message. It appears to be working just fine. > > > > 73! > > Jack, W6FB > > > > On Apr 2, 2020, at 9:41 AM, 1lasportsman 1lasportsman > > <1lasports...@cox.net mailto:1lasports...@cox.net > > mailto:1lasports...@cox.net mailto:1lasports...@cox.net > wrote: > > > > > > > I am trying to use the utility to see radio > > > > > > I am getting this error message > > > > > > KX3 MCU revision 02.90 rs232 speed 38400 bit/s > > > > > > IT worked before but I get this now > > > > > > any ideas the radio works fine but no utility with computer > > > .I tried this on 2 computers same error. > > > > > > Bill > > > > > > WF9m > > > __ > > > Elecraft mailing list > > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > > Help: http://mailman.qth.net/mmfaq.htm > > > Post: mailto:Elecraft@mailman.qth.net > > > mailto:Elecraft@mailman.qth.net mailto:Elecraft@mailman.qth.net > > > 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 > > > Message delivered to jackbrin...@me.com > > > mailto:jackbrin...@me.com mailto:jackbrin...@me.com > > > mailto:jackbrin...@me.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 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 > Message delivered to 1lasports...@cox.net mailto:1lasports...@cox.net > __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] kx3 utility
I am using the KXusb cable from computer and acc1 plug on radio but it does not connect with radio. Do I need to change the radio speed to 38400 or is it automatic? If so looked in manual and did not see how Bill > On April 2, 2020 at 11:54 AM Jack Brindle mailto:jackbrin...@me.com > wrote: > > > The utility is telling you that it is communicating with your KX3 at > 38400 bits/sec. The KX3 has firmware revision 2.90. > This is not an error message. It appears to be working just fine. > > 73! > Jack, W6FB > > > > On Apr 2, 2020, at 9:41 AM, 1lasportsman 1lasportsman > <1lasports...@cox.net mailto:1lasports...@cox.net > wrote: > > > > I am trying to use the utility to see radio > > > > I am getting this error message > > > > KX3 MCU revision 02.90 rs232 speed 38400 bit/s > > > > IT worked before but I get this now > > > > any ideas the radio works fine but no utility with computer .I > > tried this on 2 computers same error. > > > > Bill > > > > WF9m > > __ > > Elecraft mailing list > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/mmfaq.htm > > Post: mailto:Elecraft@mailman.qth.net > > 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 > > Message delivered to jackbrin...@me.com mailto:jackbrin...@me.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] kx3 utility
The utility is telling you that it is communicating with your KX3 at 38400 bits/sec. The KX3 has firmware revision 2.90. This is not an error message. It appears to be working just fine. 73! Jack, W6FB > On Apr 2, 2020, at 9:41 AM, 1lasportsman 1lasportsman <1lasports...@cox.net> > wrote: > > I am trying to use the utility to see radio > > I am getting this error message > > KX3 MCU revision 02.90 rs232 speed 38400 bit/s > > IT worked before but I get this now > > any ideas the radio works fine but no utility with computer .I tried this on > 2 computers same error. > > Bill > > WF9m > __ > 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 > Message delivered to jackbrin...@me.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 Message delivered to arch...@mail-archive.com
[Elecraft] kx3 utility
I am trying to use the utility to see radio I am getting this error message KX3 MCU revision 02.90 rs232 speed 38400 bit/s IT worked before but I get this now any ideas the radio works fine but no utility with computer .I tried this on 2 computers same error. Bill WF9m __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - NOT K3S - issue: TX Calibration fails on 6m only
I perform "radio maintenance" about every 2nd month or so.
That includes check frequency {adjust REF CAL as necessary}, check power
output on all bands {run TX Gain Cal as necessary}, receiver sensitivity
{run RX Gain cal as necessary} and then perform a full back up of the
configuration data. At the same time, I'm amazed at how stable and
accurate the radio maintains in all regards.
I've not experienced any failures of the TX gain calibration except when
the KPA3A had issues. That was replaced with a Rev E unit and no
problems observed since then.
73
Bob, K4TAX
On 4/2/2020 9:01 AM, hawley, charles j jr wrote:
I had the same issue with a brand new K3S. It failed a couple times and then it
passed once...so I left it there. I have not been on 6M but I assume it will
work fine. I do feel apprehensive though about running the cal again.
Chuck Hawley
c-haw...@illinois.edu
Amateur Radio, KE9UW
aka Jack, BMW Motorcycles
From: elecraft-boun...@mailman.qth.net on behalf
of Jim Spears
Sent: Thursday, April 2, 2020 8:12 AM
To: elecraft@mailman.qth.net
Subject: [Elecraft] K3 - NOT K3S - issue: TX Calibration fails on 6m only
I am helping a friend upgrade an older K3/100 (s/n 798) after he recently
acquired it from estate of a SK. I have brought firmware forward one or two
versions and installed the KIO3B board set. The radio has main RX only and
the KSYN3A upgrade. It does have the KANT3 antenna tuner.
I ran the 5 watt TX Calibration and it failed due to high swr on 6m only. I
thought this curious so ran this test against one of my K3S with the same
high quality dummy load and cable. It passed. I also scanned the dummy
load with my RigExpert and it is flat to at least 2m.
We would appreciate any suggestions as to how to further troubleshoot this
issue. My friend says that 6m is not important to him - today - but
tomorrow might be a different story. It seems reasonable to us that so long
as we are working on it, we should leave it fully operational.
I have not looked to see if the front panel to main board pin upgrade or any
other hardware mod has been performed.
Jim
N1NK
__
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[Elecraft] Transverter wanted
Anyone have a XV-144 transverter for sale, unbuilt or in good operating condition? Contact me direct. Thanks - George __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] K3 - NOT K3S - issue: TX Calibration fails on 6m only
I had the same issue with a brand new K3S. It failed a couple times and then it passed once...so I left it there. I have not been on 6M but I assume it will work fine. I do feel apprehensive though about running the cal again. Chuck Hawley c-haw...@illinois.edu Amateur Radio, KE9UW aka Jack, BMW Motorcycles From: elecraft-boun...@mailman.qth.net on behalf of Jim Spears Sent: Thursday, April 2, 2020 8:12 AM To: elecraft@mailman.qth.net Subject: [Elecraft] K3 - NOT K3S - issue: TX Calibration fails on 6m only I am helping a friend upgrade an older K3/100 (s/n 798) after he recently acquired it from estate of a SK. I have brought firmware forward one or two versions and installed the KIO3B board set. The radio has main RX only and the KSYN3A upgrade. It does have the KANT3 antenna tuner. I ran the 5 watt TX Calibration and it failed due to high swr on 6m only. I thought this curious so ran this test against one of my K3S with the same high quality dummy load and cable. It passed. I also scanned the dummy load with my RigExpert and it is flat to at least 2m. We would appreciate any suggestions as to how to further troubleshoot this issue. My friend says that 6m is not important to him - today - but tomorrow might be a different story. It seems reasonable to us that so long as we are working on it, we should leave it fully operational. I have not looked to see if the front panel to main board pin upgrade or any other hardware mod has been performed. Jim N1NK __ 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 Message delivered to c-haw...@illinois.edu __ 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 Message delivered to arch...@mail-archive.com
[Elecraft] K3 - NOT K3S - issue: TX Calibration fails on 6m only
I am helping a friend upgrade an older K3/100 (s/n 798) after he recently acquired it from estate of a SK. I have brought firmware forward one or two versions and installed the KIO3B board set. The radio has main RX only and the KSYN3A upgrade. It does have the KANT3 antenna tuner. I ran the 5 watt TX Calibration and it failed due to high swr on 6m only. I thought this curious so ran this test against one of my K3S with the same high quality dummy load and cable. It passed. I also scanned the dummy load with my RigExpert and it is flat to at least 2m. We would appreciate any suggestions as to how to further troubleshoot this issue. My friend says that 6m is not important to him - today - but tomorrow might be a different story. It seems reasonable to us that so long as we are working on it, we should leave it fully operational. I have not looked to see if the front panel to main board pin upgrade or any other hardware mod has been performed. Jim N1NK __ 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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] 75 ohm coax
I have used TV RG6 for over 30 years. Usually 50 feet or less and it handled the output of my SB200 amp well. In Ecuador that was the only coax readily available and it worked well. I recently bought a roll of 250 feet at Walmart for $30. Checked the loss of 100 feet and was about 1.5 dB at 145 MHz. Not as good as open wire feedline but for coax very workable. Cannot beat the price. I also have used the "F" connectors up to about 600 watts with no problem and now find BNC conn at Home Depot made for RG6 Coax. There is a lot of discussion about using RG6, usually from those who have not used it but have heard it is not good. It is definitely better than RG174 but heavier. I have been fortunate to have found good RG6 but I always test it before use. It works well in an ugly balun also at HF. I usually use the 25 foot lengths found already made with connectors on each end. I have used two runs in parallel, center conductors of course, to feed a doublet for multiband HF. 50 feet lengths feed my 6 and 2 meter verticals. Dr. Don W4BWS God Bless All Ham Radio does not make the world go round. Ham Radio is what makes the ride worthwhile. On Wed, Apr 1, 2020 at 9:38 PM Don Wilhelm wrote: > The voltage allowable on 75 ohm 1/2 inch hardline far exceeds the > voltage allowable for RG-213. No problem at the limit of 1500 watts for > the ham bands. > > Even RG-6 will withstand 1500 watts with no problems. > > 73, > Don W3FPR > > On 4/1/2020 4:38 PM, Gmail wrote: > > Careful, 75 ohms was picked for cable TV receiving Coax because it was > lower loss then 50 ohms but it could not handle high power as 50 ohms > could. 50 ohms is a power, loss compromise. 35 ohms For high power high > loss, 50 ohms compromise, 75 ohms low loss low power. > > Ray > > W8LYJ > > > __ > 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 > Message delivered to w4b...@gmail.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 Message delivered to arch...@mail-archive.com
Re: [Elecraft] VF Varies With Frequency
I put a shorted 1/4 wave stub — about a foot long on 144 MHz — on the coax to my 2m beam. The beam is right under my HF antenna, and thanks to the stub I can run 1.3 kW on 40-10m with absolutely no interference to the 2m rig, and no effect on 2m SWR. Before I had the stub, hitting the key on the HF rig caused the 2m transceiver to reboot. The stub is near the radio, although I don’t know if that matters. I just used the published VF for the coax to figure the length. To be fair, I should mention that the 2m beam is vertically polarized and the HF antenna is horizontal. But they are just a few feet apart. Victor 4X6GP > On 1 Apr 2020, at 20:38, Jim Brown wrote: > > On 4/1/2020 7:58 AM, Don Wilhelm wrote: >> When dealing with a length of transmission line, the use of the '468' factor >> should not be used - compute the actual wavelength and then apply the >> velocity factor. > > There is yet another variable -- VF varies with frequency. At low > frequencies, it is lower (slower), increasing until it converges to the > published value at VHF. For this reason, matching sections and stubs must be > measured at or near the operating frequency with an analyzer or as a stub > placed in line with a generator and receiver. They should be cut long, then > trimmed so that the null in that generator/receiver circuit is heard, or the > analzyer reads a short or open. > > How much is this variation? For typical transmission lines, it's on the order > of 1% from 80M, a bit more for 160M as compared to the published value. If > what you're building is a stub to kill harmonics, it's the difference between > the CW and phone bands on 80M. > > 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 > Message delivered to k2vco@gmail.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 Message delivered to arch...@mail-archive.com
