Jim, you took me down memory lane on this one! In my youth, from 1968 until they closed shop for good in 1971, I was a precision electroplater for a coax connector firm by the name of Gramar in Wakefield and Woburn, MA, making products under US Govt contract for many military applications, Western Electric, and others. We were also supplying vast numbers of very specialized connectors for the SST aircraft project before the Concorde won out. Our principle competitor in the day was Amphenol. Incredibly, the entire plating shop consisted of only three men working at strung wire and barrel plating, but we could do thousands a day, of every imaginable kind. I remember setting up the gold plating job on many occasions, where I started overnight jobs of one million beryllium copper contacts that received 50 millionths of an inch thickness in one small barrel. As you demonstrated each connector, my eyes could see them in their various parts prior to them being assembled. We did awesome work, if I must brag. I would be pleased to know if you ever screwed one of our Gramars together. I have been watching your videos in preparation to enter the Ham hobby at long last. I've been thinking about it since I built a crystal radio in 1962, and I've almost made up my mind. 😊
I enjoy your videos. I myself like to disconnect my antennas and ground them instead of just laying them off to a side somewhere. I designed a grounding block made with so-239s so I would have a place to "park" my antennas when not in use. Many folks have burned down their houses from the arc between the center conductor and shield by coming in contact with flammable carpet, drapes, and newspapers. I also disconnect my a/c power. I use Alpha Deltas to help with surges.
Awesome video, Jim. I think BNC and TNC are "Bayonet Neill-Concelman" and "Threaded Neill-Concelman" developed by Paul Neill of Bell labs and Carl Concelman of Amphenol. I just put that information in a PowerPoint presentation I did at work.
Hi Jim, Very good information. I've been using connector with the teflon centers and switched to the crimped shield PL-259. I find they are easier to assemble and always give a good shield connection. Wish your store was still open to keep stocked up on connectors and other items. 73 WB3BJU
Hi Jim. I keep hearing about how lossy pl259 connectors are at UHF so, I have a question that may sound confrontational but it completely is not. So, here goes - Why do transceiver manufacturers build VHF/UHF radios using so239 antenna connectors? Would it not be more useful to use a more appropriate connector design? And, what connector design might that be? I look forward to your answer and thank you for all the useful information you provide in your videos!!
(I'm not W6LG) It seems to be a USA preference (for amateur gear). Oddly enough, some mfgs use N connectors on their EMEA or Asia destined products and my Diamond 2/70cm dual band is N at the base. It's not so much that they're lossy as they aren't impedance matched like N type are so there can be mis match losses depending on frequency. One uhf pair isn't going to kill your signal at 2 meters, but additional connections should be 50ohm N type. I've seen testing that showed a significant loss around 400Mhz and tapering back down around 440, so if losses at 70cm were critical to you, you might consider swapping the connector in the chassis. (N are usually rated to higher power than BNC, also be careful to get 50 vs the 75 ohm) Jim W6JMF
great video Jim, I have a question about lightning. ..when I was a kid back in cb days we unplugged the coax and stuck the end in s glass jar...I forgot all about that til you mentioned the lightning. .what do you do with your coax?...tnx again. JIM. ..KB8YBG
A UHF connector is best at HF frequencies because of the inherent large surface area of contact between components which reduces voltage variations and therefore stable RF flow. This is a very basic description but it's good enough. Just think Low Freq's and Bigger Surface Area is Good :-)
Jim, Thanks for all of you know how. I am not sure if you will read and or reply but I will gladly accept anyone's input at this time. I am 55, been wanting to be a ham for the longest time and now I am taking my test in Nov. I already bought a Yaesu ft8800 and a Yaesu ft-2900 for the car. Along with a VX50 hand held. I cant find a group here in Charlotte that will even reply to an email so here I am asking you. I am going to use a Jpole from Arrow. down the side of the 2 story home. is LMR400 a good cable and is the PL259 still King of connectors? Thanks in advance !
Yes, LMR 400 is fine and the PL259 is also fine. I highly recommend that you put your efforts into HF and not VHF/UHF just for the reasons you talked about. Get on HF. It is the way to go. Sure have some VHF equipment but save your extra money for HF gear so you can talk around the world. 73, Jim
Well, thanks Jim. I appreciate you taking the time to respond to my question. The more I watch your videos, the more I ,wish you live closer to me. I have a heck of a time finding anyone local who can either look at great or answer any questions. I have so many things that I wonder about and have to read forums and watch videos and and at the end of the day when I am done, my brain must look like a bowl of loose oatmeal. Without pestering you, I would like to ask your advice from time to time if thats ok. Again, I appreciate your time and devotion to the trade. God bless and thanks !
Can you use F type connectors for connecting the Transceiver via a pl259 to a f type wall socket the other end connected to the antenna as I have been told you can not use F type connectors? As there 75 ohms and there would be to much loss? the ones I have ordered are for RG58 50 ohms though my friend does not believe me that they are 50ohms. I am hoping to connect a Co Linear Antenna Diamond X-30N with RG142 coax. the Antenna will have an N type connector going to a Lightning Arrestor like the one you designed . From the Arrestor connected via N type connector in to the house to an f type connector to the back of an F type socket on wall. then an f type to pl259 patch lead to the Radio Equipment. Will this work?
Apologies for my (probable) ignorance but: the impedance of an adapter is - if I am not wrong - a different thing than the impedance of a transmission line. It is also a different concept than the output impedance of a radio, considering a radio as a signal generator (where impedance matching is a requirement for optimal power transfer). Am i damn wrong?
@NamasenITN: It is a sine wave impedance. The impedance is dependent of the frequency used. (a PL 259/SO 239 connector has a 'non-constant surge impedance' above 100 MHz; it creates electrical signal reflections).
I like a BNC or an N connector in most applications. Since feedline losses are huge at UHF, I would use a larger coax cable like LMR400 or better and an N connector. It is not a matter of ignorance at all. It is a confusing topic that you can spend hours learning about and still be sure what to use. Thanks for asking. 73, Jim Heath W6LG
Jim, you took me down memory lane on this one! In my youth, from 1968 until they closed shop for good in 1971, I was a precision electroplater for a coax connector firm by the name of Gramar in Wakefield and Woburn, MA, making products under US Govt contract for many military applications, Western Electric, and others. We were also supplying vast numbers of very specialized connectors for the SST aircraft project before the Concorde won out. Our principle competitor in the day was Amphenol. Incredibly, the entire plating shop consisted of only three men working at strung wire and barrel plating, but we could do thousands a day, of every imaginable kind. I remember setting up the gold plating job on many occasions, where I started overnight jobs of one million beryllium copper contacts that received 50 millionths of an inch thickness in one small barrel. As you demonstrated each connector, my eyes could see them in their various parts prior to them being assembled. We did awesome work, if I must brag. I would be pleased to know if you ever screwed one of our Gramars together. I have been watching your videos in preparation to enter the Ham hobby at long last. I've been thinking about it since I built a crystal radio in 1962, and I've almost made up my mind. 😊
Very interesting! Any issues with copper beryllium(spelling)? Go all the way to the Extra Class. It is worth it! 73, Jim
I enjoy your videos. I myself like to disconnect my antennas and ground them instead of just laying them off to a side somewhere. I designed a grounding block made with so-239s so I would have a place to "park" my antennas when not in use.
Many folks have burned down their houses from the arc between the center conductor and shield by coming in contact with flammable carpet, drapes, and newspapers. I also disconnect my a/c power. I use Alpha Deltas to help with surges.
Awesome video, Jim.
I think BNC and TNC are "Bayonet Neill-Concelman" and "Threaded Neill-Concelman" developed by Paul Neill of Bell labs and Carl Concelman of Amphenol.
I just put that information in a PowerPoint presentation I did at work.
Hi Jim,
Very good information. I've been using connector with the teflon centers and switched to the crimped shield PL-259. I find they are easier to assemble and always give a good shield connection. Wish your store was still open to keep stocked up on connectors and other items. 73 WB3BJU
nice - thank you hearing from you again :-) vy 73 de Erwin, HB9GNK
Glad to see another video, Jim! 73 de W7KZU
great information...thank you
another good video Jim, good explanation of things, thanks and keep up the good work, hope you are doing well. 73..wd0akx
yes!
Good Info Jim, Thanks.
Hi Jim. I keep hearing about how lossy pl259 connectors are at UHF so, I have a question that may sound confrontational but it completely is not. So, here goes - Why do transceiver manufacturers build VHF/UHF radios using so239 antenna connectors? Would it not be more useful to use a more appropriate connector design? And, what connector design might that be? I look forward to your answer and thank you for all the useful information you provide in your videos!!
that was my question too. Sorry, I'm new to all this. Thanks!!
(I'm not W6LG) It seems to be a USA preference (for amateur gear). Oddly enough, some mfgs use N connectors on their EMEA or Asia destined products and my Diamond 2/70cm dual band is N at the base. It's not so much that they're lossy as they aren't impedance matched like N type are so there can be mis match losses depending on frequency. One uhf pair isn't going to kill your signal at 2 meters, but additional connections should be 50ohm N type. I've seen testing that showed a significant loss around 400Mhz and tapering back down around 440, so if losses at 70cm were critical to you, you might consider swapping the connector in the chassis. (N are usually rated to higher power than BNC, also be careful to get 50 vs the 75 ohm) Jim W6JMF
great video Jim, I have a question about lightning. ..when I was a kid back in cb days we unplugged the coax and stuck the end in s glass jar...I forgot all about that til you mentioned the lightning. .what do you do with your coax?...tnx again.
JIM. ..KB8YBG
A UHF connector is best at HF frequencies because of the inherent large surface area of contact between components which reduces voltage variations and therefore stable RF flow. This is a very basic description but it's good enough. Just think Low Freq's and Bigger Surface Area is Good :-)
Ade Larsen I am not able to verify that on a VNA or TDR.
Hi jim, can you do a video on lightning arrestor and making a choke for your hf antenna. ..tnx. jim
Thank you Jim! 73s - n0gft
Jim, Thanks for all of you know how. I am not sure if you will read and or reply but I will gladly accept anyone's input at this time. I am 55, been wanting to be a ham for the longest time and now I am taking my test in Nov. I already bought a Yaesu ft8800 and a Yaesu ft-2900 for the car. Along with a VX50 hand held. I cant find a group here in Charlotte that will even reply to an email so here I am asking you. I am going to use a Jpole from Arrow. down the side of the 2 story home. is LMR400 a good cable and is the PL259 still King of connectors? Thanks in advance !
Yes, LMR 400 is fine and the PL259 is also fine.
I highly recommend that you put your efforts into HF and not VHF/UHF just for the reasons you talked about. Get on HF. It is the way to go. Sure have some VHF equipment but save your extra money for HF gear so you can talk around the world. 73, Jim
Well, thanks Jim. I appreciate you taking the time to respond to my question. The more I watch your videos, the more I ,wish you live closer to me. I have a heck of a time finding anyone local who can either look at great or answer any questions. I have so many things that I wonder about and have to read forums and watch videos and and at the end of the day when I am done, my brain must look like a bowl of loose oatmeal. Without pestering you, I would like to ask your advice from time to time if thats ok. Again, I appreciate your time and devotion to the trade. God bless and thanks !
Can you use F type connectors for connecting the Transceiver via a pl259 to a f type wall socket the other end connected to the antenna as I have been told you can not use F type connectors? As there 75 ohms and there would be to much loss? the ones I have ordered are for RG58 50 ohms though my friend does not believe me that they are 50ohms.
I am hoping to connect a Co Linear Antenna Diamond X-30N with RG142 coax. the Antenna will have an N type connector going to a Lightning Arrestor like the one you designed . From the Arrestor connected via N type connector in to the house to an f type connector to the back of an F type socket on wall. then an f type to pl259 patch lead to the Radio Equipment. Will this work?
Apologies for my (probable) ignorance but: the impedance of an adapter is - if I am not wrong - a different thing than the impedance of a transmission line. It is also a different concept than the output impedance of a radio, considering a radio as a signal generator (where impedance matching is a requirement for optimal power transfer). Am i damn wrong?
@NamasenITN: It is a sine wave impedance. The impedance is dependent of the frequency used. (a PL 259/SO 239 connector has a 'non-constant surge impedance' above 100 MHz; it creates electrical signal reflections).
What are the best connectors to use for UHF and VHF coaz connections
Forgive my ignorance please, but what connectors should be used for UHF?
I like a BNC or an N connector in most applications. Since feedline losses are huge at UHF, I would use a larger coax cable like LMR400 or better and an N connector. It is not a matter of ignorance at all. It is a confusing topic that you can spend hours learning about and still be sure what to use. Thanks for asking. 73, Jim Heath W6LG
I need the cap..... I was about to skip your vid then I heard what I needed
Jim, what type of antenna should i use with a yaesu ftm-3200
KM4WDK
if you are installing it as a base station radio i use the ed fong antenna bought on ebay on mine and it works great. 73s KI7NAD
Sooo about Taiwan and China....