I'm over here thinking wow, i must be lucky my entire life. All my different mobile setups have used 3ft jumpers from driver to main box and never had issues. And coax length to antenna has always been whatever it took to get the job done. I've never had to attenuate coax by length to fix reflected power. I say this now, watch my next setup require a lot of coax length tuning. Thanks Rooster i appreciate you sharing your experience.
I ran into this problem with my mobile setup. I run a 2 pill Palomar amp and when I first hooked it up I tried a 3ft jumper cause that’s all I needed to reach. But swr was rather high so I tried a 6 ft and it helped so I ended up going with a 9ft and swr is about 1.2 all around the band. Thanks for the videos, I watch every one.
Thanks man I was about to buy a swr/power meter with a 3ft jumper.. I’ll definitely go with a 6ft even tho I’m not running a amp ..I’m just getting into radio so I appreciate your video help save a person money!
7:52 Before antenna analysers were the norm, most of us just used a simple CB SWR meter to tune the antenna. Most antennas are designed to have a 50 Ohm impedance, as is the correct coax. As long as the radio sees a low SWR, I wouldn't get to hung up on measuring impedance.
I tried a 10 foot, then a 6 foot on my mobile with an RM kl203p with Mckinley, relay was still sticking. Ended up buying a quality 1 foot jumper and the amp now works perfect.
It is a very weird thing about jumpers. And yeah, there is a hell of a lot of debate over length of jumpers too, always has been. I am one of those OG guys that's been playing radio for pushing 45 years here myself. Every installation is different, different locations, types of antennas and equipment, i have seen it and done it all more than a few times here. I have had it happen where i moved to a new house, same exact equipment set up the same way at the previous house with even the same exact jumpers and coax length to the antenna/antenna's, and have weird things happen that didn't make any sense to me at all. Weird RFI issues, swr issues that didn't make sense. I don't have or maintain a practice or any kind of a policy here about jumper length, i of course prefer to use the minimal length needed to facilitate connection of all the equipment. I make use of 2 and 3 foot jumpers here most of the time as i don't care for a ton of coax under the desk and so on, and i like my equipment on the desk how i like it, not where my jumpers dictate where it can sit. I look at it like this, everything between the microphone to the antenna is kinda like cookin' up a pot of stew or chili. You can use the same ingredients and been doing it like that for 40 years, but every once in a while you will cook up a batch that's too salty, needs some more of this or that, too much onion or not enough, etc When your getting down to the last hour or so and your giving it a taste test, too much salt? Throw a peeled tater in it to pull the salt out a bit. Not enough garlic or onion? Break out a skillet and saute another one up real quick and chuck it in the pot for that last hour, so on and so forth. Radio is the same way, sometimes lengthening, or shortening a jumper will make that weird stuff go away and make everything right, just like tuning that pot of chili up. Everybody likes a good pot of chili, am i right? :)
Different Strokes for different Folkes mate, same here some 40yr+ Cb (Fm 🇬🇧) but new(ish) to Ssb/Hf, but I can say every set up be it QTH/Mobile/HOTA Act etc, there will always be a difference in each set up. Jumpers or 'Patch' leads to my Amp/Swr metre I have always kept short, maybe 2ft & standard plugs, I do got some Rg213 x 30" 2½ft somewhere but not needed. Although I am still watching the video above while replying to your comment, what would you recommend and would longer jumpers actually do over short 🤔 maybe I should watch the Gideon again. Lol. 73's 407 Mcr Uk 👋
A big problem nowadays also with 18 wheeler trucks is the antennas not getting a good ground. Like the 38,42,50 ohm you spoke of. You don’t get a smooth swr curve.
Alot of people don't know about jumper length, quality coax, proper length coax good video rooster. I finally switched to all lmr400 in my mobile works awsome!
Myth, unfortunately. It's far more likely that the relay is sticking due to stray RF. Poor grounding and magmount antennas can cause this, especially at high power. If the coax is poor quality, then there will be leakage from the shield inside. People often confuse Velocity Factor with patch lead length. At the end of the day, it just needs to be long enough to connect between the radio, amp and antenna. As many CB amps use RF sensing to key them up, this also could be a route for the stray RF to causing a sticky relay...
Can't call something a myth when it's happened time and time again in different setups, different amps, antennas, mobiles , bases and so on. I've had dozens of customers resolve similar issues by eliminating jumpers 3ft long or less. So you're welcome to believe it's a myth. I'm sure some people still believe in Santa Claus.
I was running 3 foot jumpers and had small issues. I bought 6-foot jumpers and my SWR went really high. I swapped the 6-foot jumper from radio to amp to 3 foot and left 6-foot jumper from amp to my meter and 50 foot to my antenna. And my SWR went back to normal. I wonder if I am taking a chance with the 3 foot behind the radio even with my SWR low?
182.28 inches for 1/2 wave length jumper on 27.205 MHz with LMR 400. 492 x 0.85 (Velocity factor) / 27.205 = 15.19 Ft. For RG 213 use velocity factor of 0.66.
@@Optimus2179 I'm not using LMR 400 I'm using RG400 aviation grade Teflon core different velocity factor entirely 492*0.695/27.205= 12.569 feet. It's been a while since I made any but I new it was about 12'
I dont understand why this would be/ you see this as a good thing - If your SWR goes down from adding length to your coax, thats not an improvement in the overall system? Measure resonance at the antenna, not the end of the feedline - if the feedlines eating it up - thats where its radiating, no? I hope this doesnt sound agressive i just dont understand
No 2 stations are the same capasatance impedence and ohmic resistance..all is variable from station to station......jumpers very very much mater ..having a ju.per outa phase can cause immediate ocilation...u need to tune your jumpers and make sure everything is phased ....
I played it safe with the amp I got from you. I run 1/2 wave length jumpers between everything. Yes sir for sure get an antenna analyzer! Well worth the money.
My AA-35ZOOM shows my impedance around 39 ohms & SWR around 1.6 on Ch. 40 (11 meters). Running roof mount (not mag mount) Wilson 1000 with short load whip. How would I rectify this?
You shouldn't be adding or taking away coax to tune your antenna. Even a 102 whip, but that's a whole nother conversation. You should be using something like a whip adjuster or riser to tune it
Well with the 102 inch whip I don't know if it's like the way it's mounted or whatever but I started with 21 ft and trimmed about a quarter maybe a half inch off of it and Maya Str meter is showing a 1.2 and I was afraid to trim anymore because I was afraid that it would go the other way so that's why I was asking about I mean that was a good question that I had never asked before did the jumpers take away from your overall length of your coax between the antenna in the amp so that's why I asked did did if I run a 6-ft jumper is that going to affect the initial length of the coax between the amp and the antenna
You know this is my 1st amp install in line so a video on the.coax between radio and.amp and amp and antenna and the.proper way to place it as I have said I'm on a whip but you would be surprised at the people screwing up good equipment because they don't know I've ask 5 people and get 4 different ways to do it I known know the proper way and insight would be awesomely helpful for lots of people most people not really sure how
Never use 3 foot never never never ....u must phase your jumpers ..u always want to null and tune each jumper to resinance .. above 6 ...I recommend 9 foot and bottom off reactance ...it will make all the world of difference
when i first got into amps 30 years ago I had the same problems using 3 ft jumpers I went with 6 ft jumpers and one 12 ft jumper and dead on the money with the swr from 100 watts to 15 k dead on!
Well, I could explain the issue with people who build their amps hooked to an Antenna with x amount of coax rather than a dummy load, and the issues that presents
@@Rooster_Radio Yikes ! The antenna analyzer is the best thing you could ever own and so many people don't realize it. It makes short work of the majority of your problems.
50 ohms. Gatta keep it all at 50 ohms.
Good video, thanks...
#12 Watkins Glen, NY waving 🤘 10:34
I'm over here thinking wow, i must be lucky my entire life. All my different mobile setups have used 3ft jumpers from driver to main box and never had issues. And coax length to antenna has always been whatever it took to get the job done. I've never had to attenuate coax by length to fix reflected power. I say this now, watch my next setup require a lot of coax length tuning. Thanks Rooster i appreciate you sharing your experience.
I ran into this problem with my mobile setup. I run a 2 pill Palomar amp and when I first hooked it up I tried a 3ft jumper cause that’s all I needed to reach. But swr was rather high so I tried a 6 ft and it helped so I ended up going with a 9ft and swr is about 1.2 all around the band. Thanks for the videos, I watch every one.
Thanks man I was about to buy a swr/power meter with a 3ft jumper.. I’ll definitely go with a 6ft even tho I’m not running a amp ..I’m just getting into radio so I appreciate your video help save a person money!
7:52 Before antenna analysers were the norm, most of us just used a simple CB SWR meter to tune the antenna.
Most antennas are designed to have a 50 Ohm impedance, as is the correct coax. As long as the radio sees a low SWR, I wouldn't get to hung up on measuring impedance.
I was one of those people until I saw multiple Dosy and other meters show a flat swr only to find out I was running a 1:6 +
I tried a 10 foot, then a 6 foot on my mobile with an RM kl203p with Mckinley, relay was still sticking. Ended up buying a quality 1 foot jumper and the amp now works perfect.
Also solder your shields to your Ferrells ...always
Wouldn't believe how many so239's I've had to replace due to crappy jumpers. Gobs of solder on the tips.
Great video Rooster thank you for the update
It is a very weird thing about jumpers. And yeah, there is a hell of a lot of debate over length of jumpers too, always has been. I am one of those OG guys that's been playing radio for pushing 45 years here myself. Every installation is different, different locations, types of antennas and equipment, i have seen it and done it all more than a few times here. I have had it happen where i moved to a new house, same exact equipment set up the same way at the previous house with even the same exact jumpers and coax length to the antenna/antenna's, and have weird things happen that didn't make any sense to me at all. Weird RFI issues, swr issues that didn't make sense. I don't have or maintain a practice or any kind of a policy here about jumper length, i of course prefer to use the minimal length needed to facilitate connection of all the equipment. I make use of 2 and 3 foot jumpers here most of the time as i don't care for a ton of coax under the desk and so on, and i like my equipment on the desk how i like it, not where my jumpers dictate where it can sit.
I look at it like this, everything between the microphone to the antenna is kinda like cookin' up a pot of stew or chili. You can use the same ingredients and been doing it like that for 40 years, but every once in a while you will cook up a batch that's too salty, needs some more of this or that, too much onion or not enough, etc When your getting down to the last hour or so and your giving it a taste test, too much salt? Throw a peeled tater in it to pull the salt out a bit. Not enough garlic or onion? Break out a skillet and saute another one up real quick and chuck it in the pot for that last hour, so on and so forth. Radio is the same way, sometimes lengthening, or shortening a jumper will make that weird stuff go away and make everything right, just like tuning that pot of chili up. Everybody likes a good pot of chili, am i right? :)
Different Strokes for different Folkes mate, same here some 40yr+ Cb (Fm 🇬🇧) but new(ish) to Ssb/Hf, but I can say every set up be it QTH/Mobile/HOTA Act etc, there will always be a difference in each set up.
Jumpers or 'Patch' leads to my Amp/Swr metre I have always kept short, maybe 2ft & standard plugs, I do got some Rg213 x 30" 2½ft somewhere but not needed.
Although I am still watching the video above while replying to your comment, what would you recommend and would longer jumpers actually do over short 🤔 maybe I should watch the Gideon again. Lol. 73's 407 Mcr Uk 👋
A big problem nowadays also with 18 wheeler trucks is the antennas not getting a good ground. Like the 38,42,50 ohm you spoke of. You don’t get a smooth swr curve.
Now I recommend that u use your ohm meter and check always every few months ...if your running big power ..always use a ohm meter
Alot of people don't know about jumper length, quality coax, proper length coax good video rooster. I finally switched to all lmr400 in my mobile works awsome!
What length is your coax?
Myth, unfortunately. It's far more likely that the relay is sticking due to stray RF. Poor grounding and magmount antennas can cause this, especially at high power.
If the coax is poor quality, then there will be leakage from the shield inside.
People often confuse Velocity Factor with patch lead length. At the end of the day, it just needs to be long enough to connect between the radio, amp and antenna.
As many CB amps use RF sensing to key them up, this also could be a route for the stray RF to causing a sticky relay...
Can't call something a myth when it's happened time and time again in different setups, different amps, antennas, mobiles , bases and so on.
I've had dozens of customers resolve similar issues by eliminating jumpers 3ft long or less.
So you're welcome to believe it's a myth. I'm sure some people still believe in Santa Claus.
I was running 3 foot jumpers and had small issues. I bought 6-foot jumpers and my SWR went really high. I swapped the 6-foot jumper from radio to amp to 3 foot and left 6-foot jumper from amp to my meter and 50 foot to my antenna. And my SWR went back to normal. I wonder if I am taking a chance with the 3 foot behind the radio even with my SWR low?
I Always Have Used Quality Coax And Co-Phase With Amphonol Ends Belden Coax Is The One For Me!
🇺🇸👍
I run 1/2 wave tuned rg400 jumpers. About 12" give or take
Keeps my styker 955 and my rig expert, mfj, and nano vna happy
182.28 inches for 1/2 wave length jumper on 27.205 MHz with LMR 400.
492 x 0.85 (Velocity factor) / 27.205 = 15.19 Ft.
For RG 213 use velocity factor of 0.66.
@@Optimus2179 I'm not using LMR 400 I'm using RG400 aviation grade Teflon core different velocity factor entirely
492*0.695/27.205= 12.569 feet. It's been a while since I made any but I new it was about 12'
I dont understand why this would be/ you see this as a good thing - If your SWR goes down from adding length to your coax, thats not an improvement in the overall system?
Measure resonance at the antenna, not the end of the feedline - if the feedlines eating it up - thats where its radiating, no?
I hope this doesnt sound agressive i just dont understand
What kind of coax do you suggest for a new base CB base? I am going to need around 50 ft.
Lmr 400 or lmr 400 ultra flex
No 2 stations are the same capasatance impedence and ohmic resistance..all is variable from station to station......jumpers very very much mater ..having a ju.per outa phase can cause immediate ocilation...u need to tune your jumpers and make sure everything is phased ....
I played it safe with the amp I got from you. I run 1/2 wave length jumpers between everything. Yes sir for sure get an antenna analyzer! Well worth the money.
How long is a 1/2 wave jumper? LMR 400 @ 27.4 Mhz. 14.52 feet?
I run 6' 9' or 12' and I use a MFJ to make them up
👍
Great video that's some good stuff 6feet jumpers work best for my setup
My AA-35ZOOM shows my impedance around 39 ohms & SWR around 1.6 on Ch. 40 (11 meters). Running roof mount (not mag mount) Wilson 1000 with short load whip. How would I rectify this?
Depends, what's the swr on 1
@@Rooster_Radio Same as on Ch.40. SWR on Ch.20 is about 1.35.
What flexible coax would you recommend to handle say 5k RMS?
Lmr600 UF or 1/2 inch super flex heliax
Do you sell or where would recommend purchasing from?
Wow. Thanks. I didn’t know this. For ever we have heard that shorter the better. I’ll start getting six footers.
Self ocilation...is a Big on issue that can be caused from tune and or just a simple bad jumper .....
So if in my case 102 in steel whip 21ft coax good quality if I use 6ft jumper what or how will this affect my intial coax length
You shouldn't be adding or taking away coax to tune your antenna. Even a 102 whip, but that's a whole nother conversation. You should be using something like a whip adjuster or riser to tune it
Well with the 102 inch whip I don't know if it's like the way it's mounted or whatever but I started with 21 ft and trimmed about a quarter maybe a half inch off of it and Maya Str meter is showing a 1.2 and I was afraid to trim anymore because I was afraid that it would go the other way so that's why I was asking about I mean that was a good question that I had never asked before did the jumpers take away from your overall length of your coax between the antenna in the amp so that's why I asked did did if I run a 6-ft jumper is that going to affect the initial length of the coax between the amp and the antenna
You know this is my 1st amp install in line so a video on the.coax between radio and.amp and amp and antenna and the.proper way to place it as I have said I'm on a whip but you would be surprised at the people screwing up good equipment because they don't know I've ask 5 people and get 4 different ways to do it I known know the proper way and insight would be awesomely helpful for lots of people most people not really sure how
Is that rg400 that you’re running? Trying to find a quality jumper that’s more flexible than this lmr400
Just mini 8. I like lmr 240uf
Never use 3 foot never never never ....u must phase your jumpers ..u always want to null and tune each jumper to resinance .. above 6 ...I recommend 9 foot and bottom off reactance ...it will make all the world of difference
Can you suggest a good quality jumper to run fatboy with my stryker 955?
Lmr400uf or 240uf. I have some listed roostercb.com
I love people running 8 pills with Amazon or ebay jumpers.
I stop using 3ft jumpers 6ft is what I use
when i first got into amps 30 years ago I had the same problems using 3 ft jumpers I went with 6 ft jumpers and one 12 ft jumper and dead on the money with the swr from 100 watts to 15 k dead on!
Lol. Do you even dare to attempt to explain the amps being built around the 3,6,9 foot jumper parameters?😬 That will take them down the rabbit hole.😯
Well, I could explain the issue with people who build their amps hooked to an Antenna with x amount of coax rather than a dummy load, and the issues that presents
@@Rooster_Radio Yikes ! The antenna analyzer is the best thing you could ever own and so many people don't realize it. It makes short work of the majority of your problems.
I’ve heard other people on UA-cam say the same thing about not using 3’ jumpers they only run 6’ and longer
EXCELLENT EXCELLENT EXCELLENT EXCELLENT EXCELLENT EXCELLENT VIDEO!!