Re: [Elecraft] Connectors
Since I've seen in my 65 years in this hobby about 65 different "proper" ways to install these things, I can't imagine NOT reusing them. For the life of me I can't understand this constant hand-wringing about a simple connector that isn't even a precision device.* Amphenol makes good stuff (I had one of their antenna rotors that would turn my house) but worshiping a PL-259 connector is a bit much, IMHO, of course. * When I see recommendations to tighten the connector with a pair of pliers, precision doesn't leap to mind. Wes N7WS On 7/12/2021 11:59 AM, Jim Brown wrote: On 7/12/2021 11:47 AM, Paul Dluehosh wrote: It may take a little work to clean up a connector with the stub of a coax cable in it, but usually the cost is low and you still end up with a real Amphenol connector. I've installed hundreds of Amphenol UHF connectors, and I can't imagine re-using one that is PROPERLY installed. 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 arch...@mail-archive.com
Re: [Elecraft] Connectors
What would you do with them, Jim? Throw them away??? Horrors. Send them to me, I’m not afraid to pry the old coax and wiring out. They re-use just fine. > On Jul 12, 2021, at 2:59 PM, Jim Brown wrote: > > I've installed hundreds of Amphenol UHF connectors, and I can't imagine > re-using one that is PROPERLY installed. Bill Coleman, AA4LR, PP-ASELMail: aa...@arrl.net Web: http://boringhamradiopart.blogspot.com Quote: "Not within a thousand years will man ever fly!" -- Wilbur Wright, 1901 __ 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] Connectors
Silver oxide is a good conductor, but the tarnish we see is silver sulfide, which is a semiconductor. That causes problems at low voltages. This StackExchange answer has more details: https://physics.stackexchange.com/a/365483 wunder K6WRU Walter Underwood CM87wj http://observer.wunderwood.org/ (my blog) > On Jul 12, 2021, at 4:06 PM, Bob Liesen wrote: > > Hi gang, > I have been told by several people who are clearly in the know of many > things, that tarnished silver is a >better< conductor than untarnished. > And I have also been told by others just as in the know, that that is a > myth. > Anyone have definite info? > > Bob WB0POQ > > On Mon, Jul 12, 2021 at 4:11 PM Bill Frantz wrote: > >> I was told that all the compounds produced when silver is >> tarnished are conductive. So, when I built a single-lever >> paddle, I used two short pieced of silver wire, obtained from a >> jeweler friend, at right angles for the contacts. I haven't had >> any contact problems with that paddle. >> >> 73 Bill AE6JV >> >> On 7/12/21 at 3:35 PM, wes_n...@triconet.org (Wes) wrote: >> >>> On 7/12/2021 11:47 AM, Paul Dluehosh wrote: ...They may look ugly with a black patina, but that may be because they have real silver plating. >>> >>> That's what TARN-X is for. >> >> --- >> Bill Frantz| Privacy is dead, get over | Periwinkle >> (408)348-7900 | it. | 150 Rivermead >> Rd #235 >> www.pwpconsult.com |- Scott McNealy (1999) | Peterborough, >> NH 03458 __ 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] Connectors
Hi gang, I have been told by several people who are clearly in the know of many things, that tarnished silver is a >better< conductor than untarnished. And I have also been told by others just as in the know, that that is a myth. Anyone have definite info? Bob WB0POQ On Mon, Jul 12, 2021 at 4:11 PM Bill Frantz wrote: > I was told that all the compounds produced when silver is > tarnished are conductive. So, when I built a single-lever > paddle, I used two short pieced of silver wire, obtained from a > jeweler friend, at right angles for the contacts. I haven't had > any contact problems with that paddle. > > 73 Bill AE6JV > > On 7/12/21 at 3:35 PM, wes_n...@triconet.org (Wes) wrote: > > >On 7/12/2021 11:47 AM, Paul Dluehosh wrote: > >>...They may look ugly with a black patina, but that may be > >>because they have real silver plating. > > > >That's what TARN-X is for. > > --- > Bill Frantz| Privacy is dead, get over | Periwinkle > (408)348-7900 | it. | 150 Rivermead > Rd #235 > www.pwpconsult.com |- Scott McNealy (1999) | Peterborough, > NH 03458 > > __ > 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 wb0...@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] Connectors
I was told that all the compounds produced when silver is tarnished are conductive. So, when I built a single-lever paddle, I used two short pieced of silver wire, obtained from a jeweler friend, at right angles for the contacts. I haven't had any contact problems with that paddle. 73 Bill AE6JV On 7/12/21 at 3:35 PM, wes_n...@triconet.org (Wes) wrote: On 7/12/2021 11:47 AM, Paul Dluehosh wrote: ...They may look ugly with a black patina, but that may be because they have real silver plating. That's what TARN-X is for. --- Bill Frantz| Privacy is dead, get over | Periwinkle (408)348-7900 | it. | 150 Rivermead Rd #235 www.pwpconsult.com |- Scott McNealy (1999) | Peterborough, NH 03458 __ 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] Connectors
On 7/12/2021 11:47 AM, Paul Dluehosh wrote: ...They may look ugly with a black patina, but that may be because they have real silver plating. That's what TARN-X is for. __ 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] Connectors
Hot take: Use cheap connectors and cable if they fit your budget and intended use and you're aware of the consequences of their failure. I've forgotten to connect an antenna to my KX3 at all and it's handled it fine, so I'm not deeply concerned about a connector failure disconnecting it. If you're putting out the legal limit and the connector's gonna be up a tower? Use the good stuff. 73, Julie On Mon, Jul 12, 2021, 15:00 Jim Brown wrote: > On 7/12/2021 11:47 AM, Paul Dluehosh wrote: > > It may take a little work to clean up a connector with the stub of a > > coax cable in it, but usually the cost is low and you still end up with > > a real Amphenol connector. > > I've installed hundreds of Amphenol UHF connectors, and I can't imagine > re-using one that is PROPERLY installed. > > 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 ju...@juliatuttle.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] Connectors
On 7/12/2021 11:47 AM, Paul Dluehosh wrote: It may take a little work to clean up a connector with the stub of a coax cable in it, but usually the cost is low and you still end up with a real Amphenol connector. I've installed hundreds of Amphenol UHF connectors, and I can't imagine re-using one that is PROPERLY installed. 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 arch...@mail-archive.com
Re: [Elecraft] Connectors
I try to also use only Amphenol (PL-259) connectors. While new Amphenol connectors, like everything else, keep getting more expensive, I find that used Amphenol connectors can usually be found at hamfests (remember them?) either as new-old-stock or having been cut off the end of an old cable. It may take a little work to clean up a connector with the stub of a coax cable in it, but usually the cost is low and you still end up with a real Amphenol connector. They may look ugly with a black patina, but that may be because they have real silver plating. 73, Paul — N4PD /radio.n...@gmail.com/ On 07/12/2021 12:51, William Levy wrote: I buy Amphenol connectors. I have for 60 years. They don't fail me. I buy better coax and hard line. Great radios. You get what you pay for. If you can't afford it don't buy cheap. Wait until your budget allows. An old boy used to laugh at me always buying 20 dollar SWR meters. He told me to stop doing that and go buy a Bird for $ 125. He told me I would anyway and why waste my money on the cheap stuff that would fail me. Just my two cents. Bill N2WL __ 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 radio.n...@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] Connectors
I buy Amphenol connectors. I have for 60 years. They don't fail me. I buy better coax and hard line. Great radios. You get what you pay for. If you can't afford it don't buy cheap. Wait until your budget allows. An old boy used to laugh at me always buying 20 dollar SWR meters. He told me to stop doing that and go buy a Bird for $ 125. He told me I would anyway and why waste my money on the cheap stuff that would fail me. Just my two cents. Bill N2WL __ 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] Connectors
Gent's back in the day there were folks that screamed and decried the fact that the S Line used RCA jacks for RF output ignoring the virtues of the frontpanel, 1 kc dials, filters, beautiful hand wiring and wouldn't touch the stuff. Collins sold 40,000 transceivers and many went to parts of the world where no one would have a local PL259 but everyone had RCA plugs to solder on RG58. There was a method to their brilliant madness. I was also taught by my elders and I am no spring chicken not to pull power cords out of the wall but to bend down and pull the plug! My two cents. Bill N2WL __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] Connectors
Now the challenge for me is bending down, and getting back up straight again! Phil w7ox On 3/15/14, 11:32 AM, William Levy wrote: I was also taught by my elders and I am no spring chicken not to pull power cords out of the wall but to bend down and pull the plug! My two cents. Bill N2WL __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] Connectors
Just a quick question: On 4/25/12 7:09 PM, Alan Bloom wrote: Since two N or UHF adapters were used, I assume the loss per connector is half the total. The vertical scale was .1 dB/division, so I estimated the insertion loss to the nearest .01 dB or so: - Type N -- UHF -- FREQ (MHz) TOTAL LOSS PER CONNECTOR TOTAL LOSS PER CONNECTOR 1.8 0 dB 0 dB 0 dB 0 dB 30 0 00 0 What are the measurements below this? I'm not sure I can work any DX at those frequencies. I always tell my microwave experimenter buddies that if I can walk there and talk to the guy, I'll do that and not worry about my radio. :) 100 0 00 0 150 0 00.02 0.01 200 0 00.03 0.015 450 0 00.18 0.09 600 0 00.26 0.13 900 0 00.66 0.33 10000.05 0.0250.80.4 13000.10.05 0.86 0.43 16000.05 0.0250.50.25 20000.05 0.0250.02 0.01 Oh, and for technical content: even though you get an impedance mismatch, at the frequencies I care about the mismatch is so short that you don't make it far around the Smith chart (easier than doing the calculations). It doesn't really matter that a UHF connector isn't exactly 50 ohms when it's a wavelength, 1/10 the wavelength. So if a UHF connector is about an inch, 10 times that is about 10 inches, or about what I think is a nanosecond is (about a foot) which is 10^9Hz or about a gigahertz. So back-of-the-envelope, UHF connectors impedance mismatch only matters around a gigahertz. This would horrify my engineering profs because MIT back-of-the-envelope calculations would require Maxwell's equations. -- Hisashi T Fujinaka - ht...@twofifty.com BSEE(6/86) + BSChem(3/95) + BAEnglish(8/95) + MSCS(8/03) + $2.50 = latte __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
[Elecraft] Connectors
(Changing to a more descriptive Subject line) 1. One nice thing about female BNC connectors is that they are compatible with male type-N connectors. Try it - they plug right in. Of course, there is no locking mechanism, so it wouldn't be good for something like a mobile installation, but otherwise it works fine and saves an adapter. 2. One advantage that BNC and N have over UHF is that the ground connection doesn't depend on the shell being properly tightened. 3. I've had excellent reliability from UHF plugs as long as I pre-tin the coax braid and solder it through the holes. That's true both with RG-8 type cable as well as the smaller RF-58 with the adapter. 4. Regarding RF loss in UHF connectors, it isn't as bad as many people think. I did an Internet search and found the Usenet posting I made on the subject about 20 (!) years ago: From: ... (Alan Bloom) Date: Fri, 18 Sep 1992 23:03:13 GMT Subject: The Truth about UHF Connectors Organization: Hewlett-Packard, Santa Rosa, CA Newsgroups: rec.radio.amateur.misc Ya gotta feel sorry for UHF connectors. Recent strings on this notes group lambasted them as worthless at VHF and above, and barely tolerable at HF. One poster called them 5 dB attenuators, and many agreed that there must be some sort of conspiracy among ham equipment manufacturers to inflict such garbage connectors on the amateur community. Today I finally remembered to bring some UHF adapters from home so I could do some relative measurements of UHF versus type-N. As expected, the type-N showed lower insertion loss at high frequencies, but the UHF connectors were hardly 5 dB attenuators. For the test I connected an HP8753 RF network analyzer through two short BNC cables into the following arrangement: _________ | | | BNC female | | N female- | | N male to | | | __| 10 dB |__| to N male |__| N female |__| BNC female |__| 10 dB |__ | Atten.| | adapter| | adapter | | adapter| | Atten.| |___| || |___| || |___| Then I repeated the measurement with the N adapters replaced with UHF. I normalized the measurements by replacing the 3 adapters with a BNC double-female. (That is, this was assumed to have 0 dB loss.) Since two N or UHF adapters were used, I assume the loss per connector is half the total. The vertical scale was .1 dB/division, so I estimated the insertion loss to the nearest .01 dB or so: - Type N -- UHF -- FREQ (MHz) TOTAL LOSS PER CONNECTOR TOTAL LOSS PER CONNECTOR 1.8 0 dB 0 dB 0 dB 0 dB 30 0 00 0 100 0 00 0 150 0 00.02 0.01 200 0 00.03 0.015 450 0 00.18 0.09 600 0 00.26 0.13 900 0 00.66 0.33 10000.05 0.0250.80.4 13000.10.05 0.86 0.43 16000.05 0.0250.50.25 20000.05 0.0250.02 0.01 Insertion loss increases until about 1300 MHz, and then starts to decrease until it is almost zero for the UHF connector at 2 GHz! At that frequency, the connectors are about 1/4 wave long (1 inch, assuming .66 velocity factor), so I assume that the two adapters are providing a conjugate match to each other. This confirms my assumption that the insertion loss is due to reflections (impedance mismatch), not absorption (true power loss). Bottom line: UHF connectors work fine through the VHF range, and are not too bad even on the 420 MHz band if you can stand about .1 dB mismatch loss per connector. By the way, I did not do the full 2-port calibration on the HP8753, so there was a couple hundredth's dB ripple in the plots. I averaged this out by eye to come up with the numbers in the above chart. AL N1AL P.S. Sorry, I guess I violated the Usenet rule against posting objective data... :=) On Wed, 2012-04-25 at 09:50 -0800, Edward R. Cole wrote: I assume all you have read this thread so not going to repeat all prior e-mail in my post. First off only place you will find PL259/SO239 UHF connectors is on ham, CB and some marine radio equipment made today. Commercial radios long have gone to other connectors with N-connectors being favored for VHF+ site located systems. Mobiles and HT's have a variety of connectors from BNC, TNC, mini-UHF, RCA-phono (gawd awful), sma and a whole host of tiny specialty connectors used on wireless stuff, smart phones, etc. In my professional life I moved most cabling to either N or BNC vs UHF. This was for reliability. BNC were normally used on RG-58 cable jumpers and lower power stuff where measurements were frequent requiring cable removal. The use
Re: [Elecraft] Connectors
Al, Great information! Yes, I can agree that properly tightened UHF connectors do not inflict much loss. I think the main problem has been with inadequate tightening - as you pointed out the shield connection requires that that UHF connectors be tight. How many hams wiggle the PL-259 connector a bit to be certain it is seated in the notch of the SO-239 - this is not a casual connector for making quick connections and disconnections. Where am I going with this - well, with the KPA100, we have long recommended disconnect the antenna when not in use to protect the wattmeter diodes from static damage. While this is a good concept, the literal interpretation of that statement may actually inflict damage because of the way the UHF connector connects. With a PL-259, the center conductor is what makes contact first - if there is a static charge on that feedline, that charge will be transferred to your equipment without a chance to bleed it off - the only way to prevent that is to either short across the feedline (if there is a ground connection for the shield) or some other means should be used to bleed off the charge before attaching a feedline with a PL-259 connector to any equipment. Type N and BNC do not have this problem - the shell makes contact first. On 4/25/2012 7:09 PM, Alan Bloom wrote: (Changing to a more descriptive Subject line) 4. Regarding RF loss in UHF connectors, it isn't as bad as many people think. I did an Internet search and found the Usenet posting I made on the subject about 20 (!) years ago: __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] Connectors
On Wed, Apr 25, 2012 at 6:09 PM, Alan Bloom n...@sonic.net wrote: ...Sorry, I guess I violated the Usenet rule against posting objective data... Ah, Alan, you are a repeat offender. However, do not feel bad. Contrary to what you may have heard, recently certain philosophers have concluded that objective data is not always bad. They argue that it is in fact one of the four basic categories of acceptable standards of proof: 1. proof by handwaving/buzzword invocation/TABLE-POUNDING 2. proof by appeal to authority/expertise/experience/common sense/universal knowledge 3. proof by mathematical or other rigorous analysis 4. proof by experimental data All the above have their adherents and detractors, all are in wide use, and all have their moments in the sun on the internet. 73, Tony KT0NY __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] Connectors
Tony, you forgot one, there's 5. Proof by Powerpoint. 73, Fred K6DGW - Northern California Contest Club - CU in the 2012 Cal QSO Party 6-7 Oct 2012 - www.cqp.org On 4/25/2012 4:55 PM, Tony Estep wrote: Ah, Alan, you are a repeat offender. However, do not feel bad. Contrary to what you may have heard, recently certain philosophers have concluded that objective data is not always bad. They argue that it is in fact one of the four basic categories of acceptable standards of proof: 1. proof by handwaving/buzzword invocation/TABLE-POUNDING 2. proof by appeal to authority/expertise/experience/common sense/universal knowledge 3. proof by mathematical or other rigorous analysis 4. proof by experimental data __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] Connectors
...just because there's no data, it doesn't mean you're wrong Einstein (probably) Sent from my iPad On Apr 25, 2012, at 8:47 PM, Fred Jensen k6...@foothill.net wrote: Tony, you forgot one, there's 5. Proof by Powerpoint. 73, Fred K6DGW - Northern California Contest Club - CU in the 2012 Cal QSO Party 6-7 Oct 2012 - www.cqp.org On 4/25/2012 4:55 PM, Tony Estep wrote: Ah, Alan, you are a repeat offender. However, do not feel bad. Contrary to what you may have heard, recently certain philosophers have concluded that objective data is not always bad. They argue that it is in fact one of the four basic categories of acceptable standards of proof: 1. proof by handwaving/buzzword invocation/TABLE-POUNDING 2. proof by appeal to authority/expertise/experience/common sense/universal knowledge 3. proof by mathematical or other rigorous analysis 4. proof by experimental data __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] Connectors
This compares well enough with my measurements... http://www.hamradio.me/graphs/connectors/UHFConnectorGraphs/Mismatch-Loss_1000.png http://www.hamradio.me/graphs/connectors/UHFConnectorGraphs/Insertion-Loss_S21_1000.png Some of the longer UHF barrels show the repeating characteristic you observed which I assume is when the different transmission line is about 1/2 wavelength long. John, kx4o On 4/25/12 7:09 PM, Alan Bloom wrote: Since two N or UHF adapters were used, I assume the loss per connector is half the total. The vertical scale was .1 dB/division, so I estimated the insertion loss to the nearest .01 dB or so: - Type N -- UHF -- FREQ (MHz) TOTAL LOSS PER CONNECTOR TOTAL LOSS PER CONNECTOR 1.8 0 dB 0 dB 0 dB 0 dB 30 0 00 0 100 0 00 0 150 0 00.02 0.01 200 0 00.03 0.015 450 0 00.18 0.09 600 0 00.26 0.13 900 0 00.66 0.33 10000.05 0.0250.80.4 13000.10.05 0.86 0.43 16000.05 0.0250.50.25 20000.05 0.0250.02 0.01 Insertion loss increases until about 1300 MHz, and then starts to decrease until it is almost zero for the UHF connector at 2 GHz! At that frequency, the connectors are about 1/4 wave long (1 inch, assuming .66 velocity factor), so I assume that the two adapters are providing a conjugate match to each other. This confirms my assumption that the insertion loss is due to reflections (impedance mismatch), not absorption (true power loss). __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] Connectors
On 4/25/2012 4:09 PM, Alan Bloom wrote: P.S. Sorry, I guess I violated the Usenet rule against posting objective data... It should be noted that in an earlier post, I noted that I had measured the loss of 1300 ft of coax with characteristics like LMR400 that had been cut into 100 ft and 200 ft lengths for a DX trip. I noted that there were at least 25 PL259s and 13 Amphenol barrels in line, and that the loss at every frequency up to 500 MHz was less than the mfr's spec for the cable at that frequency. While I did not go to the extent of finding and measuring 1,300 ft of the same coax and subtracting out the loss, I submit that my measurements show that the loss in those 38 connectors is negligible to at least 500 MHz. And I also submit that not every small deviation from the ideal MATTERS in every real world conditions. Good engineering is making good choices for a given situation. The world does not need the $800 hammers demanded by certain military specs. Shouting down? Hardly -- when completely illogical arguments were presented as justification for a position I pointed them out. Also -- I don't trust the precision of loss measurements for very small losses -- there are two many factors that can pollute the measurement, and often the accuracy of the instrumentation is a significant.fraction of the result being measured. For example, try getting a good number for the loss of 100 ft of LMR400 at 1.8 MHz. You'd better be measuring at least 1,000 ft to get even 10% accuracy! Several years ago, a VE1 (RGB, I think) sent me data for measurements he had made of a sizable number of UHF connectors in a string. His numbers for loss in a single connector were significantly less than what Alan has posted. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] Connectors
It's nice to have some fresh air amongst the smoke. Thanks Jim. I have been using UHF connectors for decades without a single problem, with the caveat that I purchase ONLY brand name (e.g.: Amphenol) connectors, take care to install them properly, and use them only once (reuse of connectors removed from other cables is not permitted in my station) . And yes, I do use type N fittings and other less common types (type C, 7/8 flange, etc.) for some work where appropriate. - Jim, KL7CC Jim Brown wrote: On 4/25/2012 4:09 PM, Alan Bloom wrote: P.S. Sorry, I guess I violated the Usenet rule against posting objective data... It should be noted that in an earlier post, I noted that I had measured the loss of 1300 ft of coax with characteristics like LMR400 that had been cut into 100 ft and 200 ft lengths for a DX trip. I noted that there were at least 25 PL259s and 13 Amphenol barrels in line, and that the loss at every frequency up to 500 MHz was less than the mfr's spec for the cable at that frequency. While I did not go to the extent of finding and measuring 1,300 ft of the same coax and subtracting out the loss, I submit that my measurements show that the loss in those 38 connectors is negligible to at least 500 MHz. And I also submit that not every small deviation from the ideal MATTERS in every real world conditions. Good engineering is making good choices for a given situation. The world does not need the $800 hammers demanded by certain military specs. Shouting down? Hardly -- when completely illogical arguments were presented as justification for a position I pointed them out. Also -- I don't trust the precision of loss measurements for very small losses -- there are two many factors that can pollute the measurement, and often the accuracy of the instrumentation is a significant.fraction of the result being measured. For example, try getting a good number for the loss of 100 ft of LMR400 at 1.8 MHz. You'd better be measuring at least 1,000 ft to get even 10% accuracy! Several years ago, a VE1 (RGB, I think) sent me data for measurements he had made of a sizable number of UHF connectors in a string. His numbers for loss in a single connector were significantly less than what Alan has posted. 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 __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
[Elecraft] Connectors
Aloha All, I know it's premature and I need to read the installation and owner's manual but was skimming through them. I just got my K3/100 kit and will build it in a few days. How do you make multiple connections to the RS232/ACC? I have a SteppIR SDA 100 antenna controller, Palstar AT-Auto automatic tuner and Rig Expert Standard TNC. I had an Icom 7600 where all I needed was a Y connector. 73 Delwyn KH6DC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] Connectors
GM: You will need one or more Y cables. They are available from a number of suppliers but you need to ensure that all 15 wires are connected thru. Most recently I got some from Winford Engineering LLC - see www.winford.com. Their part No. CDY15HDMMF-1. 73, Doug VE3MV - Original Message - From: Anndel ann...@hawaii.rr.com To: Elecraft@mailman.qth.net Sent: Sunday, October 02, 2011 3:39 AM Subject: [Elecraft] Connectors Aloha All, I know it's premature and I need to read the installation and owner's manual but was skimming through them. I just got my K3/100 kit and will build it in a few days. How do you make multiple connections to the RS232/ACC? I have a SteppIR SDA 100 antenna controller, Palstar AT-Auto automatic tuner and Rig Expert Standard TNC. I had an Icom 7600 where all I needed was a Y connector. 73 Delwyn KH6DC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] Connectors
Anndel: Sorry I didn't read your message close enough - my comments only apply to the ACC connector. The RS232 connector is a different situation and I don't believe the Y approach will work. 73, Doug - Original Message - From: D Joyce d_jo...@sympatico.ca To: Anndel ann...@hawaii.rr.com Cc: Elecraft List elecraft@mailman.qth.net Sent: Sunday, October 02, 2011 7:32 AM Subject: Re: [Elecraft] Connectors GM: You will need one or more Y cables. They are available from a number of suppliers but you need to ensure that all 15 wires are connected thru. Most recently I got some from Winford Engineering LLC - see www.winford.com. Their part No. CDY15HDMMF-1. 73, Doug VE3MV - Original Message - From: Anndel ann...@hawaii.rr.com To: Elecraft@mailman.qth.net Sent: Sunday, October 02, 2011 3:39 AM Subject: [Elecraft] Connectors Aloha All, I know it's premature and I need to read the installation and owner's manual but was skimming through them. I just got my K3/100 kit and will build it in a few days. How do you make multiple connections to the RS232/ACC? I have a SteppIR SDA 100 antenna controller, Palstar AT-Auto automatic tuner and Rig Expert Standard TNC. I had an Icom 7600 where all I needed was a Y connector. 73 Delwyn KH6DC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
Re: [Elecraft] Connectors
All you need is the DB-9 serial Y connectors described by SteppIR and Palstar. For your SteppIR, see http://www.steppir.com/files/Y%20-%20Cable.pdf and http://www.steppir.com/files/Transceiver%20Interface%20Operation%205-28-09.p df I found a chapter titled Radio/Computer Serial Data Y Interface in the Palstar AT-Auto manual. 73 de Dick, K6KR -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Anndel Sent: Sunday, October 02, 2011 12:40 AM To: Elecraft@mailman.qth.net Subject: [Elecraft] Connectors Aloha All, I know it's premature and I need to read the installation and owner's manual but was skimming through them. I just got my K3/100 kit and will build it in a few days. How do you make multiple connections to the RS232/ACC? I have a SteppIR SDA 100 antenna controller, Palstar AT-Auto automatic tuner and Rig Expert Standard TNC. I had an Icom 7600 where all I needed was a Y connector. 73 Delwyn KH6DC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
