Hello everyone. I just purchased a M2 leopack antenna system and I was reading about different coax cables to use for low loss. Since I am mounting the antenna only about 10 feet off the ground, 50 foot will be enough to go into the shack. I wanted to purchase RG8x but read that the best way to go is with LMR400. What I dislike about it is that its much wider and very stiff, and will make it difficult around bends. I also have the Az/alt rotator which I will have to loop each antenna to have enough for turns. Any other suggestions out there for an alternative to LMR-400?Thanks Frank KB2CWN
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Belden 9913f7
On Fri, Feb 17, 2017 at 3:17 PM, Frank Staffa Jr. via AMSAT-BB amsat-bb@amsat.org wrote:
Hello everyone. I just purchased a M2 leopack antenna system and I was reading about different coax cables to use for low loss. Since I am mounting the antenna only about 10 feet off the ground, 50 foot will be enough to go into the shack. I wanted to purchase RG8x but read that the best way to go is with LMR400. What I dislike about it is that its much wider and very stiff, and will make it difficult around bends. I also have the Az/alt rotator which I will have to loop each antenna to have enough for turns. Any other suggestions out there for an alternative to LMR-400?Thanks Frank KB2CWN
Sent from Yahoo Mail on Android _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
My very first outdoor antennas were connected via Belden 9913, and with extreme care in installing the N connectors onto the end and to the antennas, they stayed watertight until a couple of years later when I accidentally ran a drill into the feedline while trying to enlarge the hole into the house for more runs of coax. But many people have problems with water accumulation in Belden 9913 type air dielectric coax so I don't recommend it. I switched to using LMR-400 and have been pleased with its performance in an installation that was up without problems for over 10 years. (Never had problems with it, just tore it all down after about 10 years to move from Minnesota to Texas!) As others have mentioned, LMR-400UF (Ultra-Flex) is an option for less stiffness in the rotator loops. Personally, I'd go ahead and use the regular LMR-400 and leave generous rotator loops, and you should be okay. That's how I put together my station in Minnesota and like I said, I had no problems with the coax in 10 years' time, before taking it all down to move to a new state. The Ultra-Flex version has noticeably greater loss than the regular LMR-400, especially in a 50-foot run on the 70cm (or higher) band. You might compromise by using LMR-400UF from the antennas to the rotator loops to just below the top of the tower, then change to regular LMR-400 from there to the rest of the 50 foot run to the radio location. You could even use a short piece of LMR-240UF for the rotator loop and then regular LMR-400 for the rest of the run, if you weren't comfortable with the stiffness of your loop.
Good luck with your installation. 73 de W0JT/5, EL09vu20, AMSAT-NA LM
On Fri, Feb 17, 2017 at 2:46 PM, Norm n3ykf normanlizeth@gmail.com wrote:
Belden 9913f7
On Fri, Feb 17, 2017 at 3:17 PM, Frank Staffa Jr. via AMSAT-BB amsat-bb@amsat.org wrote:
Hello everyone. I just purchased a M2 leopack antenna system and I was
reading about different coax cables to use for low loss. Since I am mounting the antenna only about 10 feet off the ground, 50 foot will be enough to go into the shack. I wanted to purchase RG8x but read that the best way to go is with LMR400. What I dislike about it is that its much wider and very stiff, and will make it difficult around bends. I also have the Az/alt rotator which I will have to loop each antenna to have enough for turns. Any other suggestions out there for an alternative to LMR-400?Thanks Frank KB2CWN
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Opinions expressed
are solely those of the author, and do not reflect the official views of
AMSAT-NA.
Not an AMSAT-NA member? Join now to support the amateur satellite
program!
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Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
There is only a .3 DB of loss difference between the regular and flex LMR400 in your 50 foot run. Nothing to worry about. I would just go with the LMR-400-UltraFlex.
Here is a link to the Times microwave coaxial cable calculator...
http://www.timesmicrowave.com/calculator/?productId=52&frequency=435&...
73 Jeff kb2m
9913f7 has a solid dielectric. Conductor migration is a problem with straight 9913, as well as other issues. Minimum bend radii need to be observed.
PL-259 connectors can be applied to f7 with a plumber's torch. Amphenol N's are easy install and easy to come by. Do look for the 9913f7 compatible ones as the center conductor is heavier.
I like Belden as quality is top notch. Flexible and long lived product. Keeping work in the US? Priceless.
A 50' run is not much to worry about. Use LMR-400 DB (cost=free) for the 130' home run to the shack on VHF. It needs no preamp. On the UHF side, LDF450A does better, but needs a preamp.
Try Craigslist for bits of cable. I dug 300' of LDF450A out of a dumpster. Still have 100'.
Tomato or tomato. Do take care as workmanship rules the longevity and weatherproof qualities of the final product. All of this stuff works. Install with a hammer? Not for long.
On Sat, Feb 18, 2017 at 7:09 AM, Jeff jeff_griffin@comcast.net wrote:
There is only a .3 DB of loss difference between the regular and flex LMR400 in your 50 foot run. Nothing to worry about. I would just go with the LMR-400-UltraFlex.
Here is a link to the Times microwave coaxial cable calculator...
http://www.timesmicrowave.com/calculator/?productId=52&frequency=435&...
73 Jeff kb2m
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On 02/17/17 14:17, Frank Staffa Jr. via AMSAT-BB wrote:
Hello everyone. I just purchased a M2 leopack antenna system and I was reading about different coax cables to use for low loss. Since I am mounting the antenna only about 10 feet off the ground, 50 foot will be enough to go into the shack. I wanted to purchase RG8x but read that the best way to go is with LMR400. What I dislike about it is that its much wider and very stiff, and will make it difficult around bends. I also have the Az/alt rotator which I will have to loop each antenna to have enough for turns. Any other suggestions out there for an alternative to LMR-400?Thanks Frank KB2CWN
Hello Frank,
You could always consider a LNA at the antennas, which sets your system noise figure early on in the receive chain and allows the use of RG-8X or similar. It's best to buy a weatherproof LNA and mount it right at the antenna/rotator with a short section of high-quality, low-loss coax (or direct connect). You'll want to run DC up the coax to power the LNA, if possible. Make sure your LNA switches itself out of the way when you remove power!
Of course, you'll lose power as heat on transmit with the higher-loss cable, but I wouldn't that is much of a problem with today's radio output levels.
Remember that you only need enough LNA gain to offset cable losses and your receiver's noise figure (NF). More than that risks overloading the front-end of your receiver and causing undesirable non-linear operation (IMD). A good place to start is about 13-15 dB of gain, if you need a concrete number.
That's my view on it, and I'm definitely no expert. It works for me. YMMV. :-)
--- Zach N0ZGO
Frank, What I did was to use LMR-400 from my radio up to the mast mounted preamp. >From the preamp there is a 5 ft piece of LMR240UF (ultra flex). 240 is a high quality thin coax and the "UF" (ultra flex) classification makes it perfect for bending and twisting as my rotor turns. If you aren't ready for preamps, then you could use a barrel to join the cables at that point until you find out that you really do need preamps for a good install. Michael Vivona
From: Frank Staffa Jr. via AMSAT-BB amsat-bb@amsat.org To: "amsat-bb@amsat.org" amsat-bb@amsat.org Sent: Friday, February 17, 2017 3:17 PM Subject: [amsat-bb] (no subject)
Hello everyone. I just purchased a M2 leopack antenna system and I was reading about different coax cables to use for low loss. Since I am mounting the antenna only about 10 feet off the ground, 50 foot will be enough to go into the shack. I wanted to purchase RG8x but read that the best way to go is with LMR400. What I dislike about it is that its much wider and very stiff, and will make it difficult around bends. I also have the Az/alt rotator which I will have to loop each antenna to have enough for turns. Any other suggestions out there for an alternative to LMR-400?Thanks Frank KB2CWN
Sent from Yahoo Mail on Android _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Similarly, I use LMR-400 Ultra-Flex from pre-amp to antenna with good results so far.
-Scott, K4KDR
================================================
-----Original Message----- From: mvivona--- via AMSAT-BB Sent: Friday, February 17, 2017 5:22 PM To: kb2cwn@yahoo.com ; amsat-bb@amsat.org Subject: Re: [amsat-bb] (no subject)
Frank, What I did was to use LMR-400 from my radio up to the mast mounted preamp.
From the preamp there is a 5 ft piece of LMR240UF (ultra flex). 240 is a
high quality thin coax and the "UF" (ultra flex) classification makes it perfect for bending and twisting as my rotor turns. If you aren't ready for preamps, then you could use a barrel to join the cables at that point until you find out that you really do need preamps for a good install. Michael Vivona
From: Frank Staffa Jr. via AMSAT-BB amsat-bb@amsat.org To: "amsat-bb@amsat.org" amsat-bb@amsat.org Sent: Friday, February 17, 2017 3:17 PM Subject: [amsat-bb] (no subject)
Hello everyone. I just purchased a M2 leopack antenna system and I was reading about different coax cables to use for low loss. Since I am mounting the antenna only about 10 feet off the ground, 50 foot will be enough to go into the shack. I wanted to purchase RG8x but read that the best way to go is with LMR400. What I dislike about it is that its much wider and very stiff, and will make it difficult around bends. I also have the Az/alt rotator which I will have to loop each antenna to have enough for turns. Any other suggestions out there for an alternative to LMR-400?Thanks Frank KB2CWN
Well, I have spent a good portion of the day trying to find preamps for my M2 leopack. I read that at the very least putting one on the 70cm antenna will help a lot with the receive. But, I just can not find any. Most of the names I came across must have went out of business because their website are no longer in existence. Any suggestions out their from you season operators out there? The ones that I got last post I couldn't find. Thanks
Sent from Yahoo Mail on Android
On Fri, Feb 17, 2017 at 3:17 PM, Frank Staffa Jr.kb2cwn@yahoo.com wrote: Hello everyone. I just purchased a M2 leopack antenna system and I was reading about different coax cables to use for low loss. Since I am mounting the antenna only about 10 feet off the ground, 50 foot will be enough to go into the shack. I wanted to purchase RG8x but read that the best way to go is with LMR400. What I dislike about it is that its much wider and very stiff, and will make it difficult around bends. I also have the Az/alt rotator which I will have to loop each antenna to have enough for turns. Any other suggestions out there for an alternative to LMR-400?Thanks Frank KB2CWN
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Advanced Receiver Research has the most cost effective mast-mounted RF switched preamps.
http://advancedreceiver.com/page10.html
SSB Electronics' line of preamps might be better, but are more expensive.
http://www.ssbusa.com/NEWSSBPREAMPS.html
73,
Paul, N8HM
On Sat, Feb 18, 2017 at 8:29 PM, Frank Staffa Jr. via AMSAT-BB amsat-bb@amsat.org wrote:
Well, I have spent a good portion of the day trying to find preamps for my M2 leopack. I read that at the very least putting one on the 70cm antenna will help a lot with the receive. But, I just can not find any. Most of the names I came across must have went out of business because their website are no longer in existence. Any suggestions out their from you season operators out there? The ones that I got last post I couldn't find. Thanks
Sent from Yahoo Mail on Android
On Fri, Feb 17, 2017 at 3:17 PM, Frank Staffa Jr.kb2cwn@yahoo.com wrote: Hello everyone. I just purchased a M2 leopack antenna system and I was reading about different coax cables to use for low loss. Since I am mounting the antenna only about 10 feet off the ground, 50 foot will be enough to go into the shack. I wanted to purchase RG8x but read that the best way to go is with LMR400. What I dislike about it is that its much wider and very stiff, and will make it difficult around bends. I also have the Az/alt rotator which I will have to loop each antenna to have enough for turns. Any other suggestions out there for an alternative to LMR-400?Thanks Frank KB2CWN
Sent from Yahoo Mail on Android _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Might have a look at SHF Elektronik. The Mini 70 might do.
http://www.shf-elektronik.de/en/
Mike
On 2017-02-18 20:34, Paul Stoetzer wrote:
Advanced Receiver Research has the most cost effective mast-mounted RF switched preamps.
http://advancedreceiver.com/page10.html
SSB Electronics' line of preamps might be better, but are more expensive.
http://www.ssbusa.com/NEWSSBPREAMPS.html
73,
Paul, N8HM
On Sat, Feb 18, 2017 at 8:29 PM, Frank Staffa Jr. via AMSAT-BB amsat-bb@amsat.org wrote:
Well, I have spent a good portion of the day trying to find preamps for my M2 leopack. I read that at the very least putting one on the 70cm antenna will help a lot with the receive. But, I just can not find any. Most of the names I came across must have went out of business because their website are no longer in existence. Any suggestions out their from you season operators out there? The ones that I got last post I couldn't find. Thanks
Sent from Yahoo Mail on Android
On Fri, Feb 17, 2017 at 3:17 PM, Frank Staffa Jr.kb2cwn@yahoo.com wrote: Hello everyone. I just purchased a M2 leopack antenna system and I was reading about different coax cables to use for low loss. Since I am mounting the antenna only about 10 feet off the ground, 50 foot will be enough to go into the shack. I wanted to purchase RG8x but read that the best way to go is with LMR400. What I dislike about it is that its much wider and very stiff, and will make it difficult around bends. I also have the Az/alt rotator which I will have to loop each antenna to have enough for turns. Any other suggestions out there for an alternative to LMR-400?Thanks Frank KB2CWN
Sent from Yahoo Mail on Android _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
--- 73, Mike, N1JEZ "A closed mouth gathers no feet"
Hello,
You may wish to consider the VHFDesign range of low noise LNA's?
http://vhfdesign.com/en/category/lna
-----Original Message----- From: AMSAT-BB [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Paul Stoetzer Sent: Sunday, February 19, 2017 02:35 PM To: kb2cwn@yahoo.com Cc: amsat-bb@amsat.org Subject: Re: [amsat-bb] (no subject)
Advanced Receiver Research has the most cost effective mast-mounted RF switched preamps.
http://advancedreceiver.com/page10.html
SSB Electronics' line of preamps might be better, but are more expensive.
http://www.ssbusa.com/NEWSSBPREAMPS.html
73,
Paul, N8HM
On Sat, Feb 18, 2017 at 8:29 PM, Frank Staffa Jr. via AMSAT-BB amsat-bb@amsat.org wrote:
Well, I have spent a good portion of the day trying to find preamps for my M2 leopack. I read that at the very least putting one on the 70cm antenna will help a lot with the receive. But, I just can not find any. Most of the names I came across must have went out of business because their website are no longer in existence. Any suggestions out their from you season operators out there? The ones that I got last post I couldn't find. Thanks
Sent from Yahoo Mail on Android
On Fri, Feb 17, 2017 at 3:17 PM, Frank Staffa Jr.kb2cwn@yahoo.com
wrote: Hello everyone. I just purchased a M2 leopack antenna system and I was reading about different coax cables to use for low loss. Since I am mounting the antenna only about 10 feet off the ground, 50 foot will be enough to go into the shack. I wanted to purchase RG8x but read that the best way to go is with LMR400. What I dislike about it is that its much wider and very stiff, and will make it difficult around bends. I also have the Az/alt rotator which I will have to loop each antenna to have enough for turns. Any other suggestions out there for an alternative to LMR-400?Thanks Frank KB2CWN
Sent from Yahoo Mail on Android _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the
official views of AMSAT-NA.
Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
_______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
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I have SSB Electronic preamps that I bought right from the USA distributor.
They're not cheap, but they work flawlessly.
http://www.ssbusa.com/NEWSSBPREAMPS.html
73, Jim KQ6EA
On 02/19/2017 01:29 AM, Frank Staffa Jr. via AMSAT-BB wrote:
Well, I have spent a good portion of the day trying to find preamps for my M2 leopack. I read that at the very least putting one on the 70cm antenna will help a lot with the receive. But, I just can not find any. Most of the names I came across must have went out of business because their website are no longer in existence. Any suggestions out their from you season operators out there? The ones that I got last post I couldn't find. Thanks
Sent from Yahoo Mail on Android
On Fri, Feb 17, 2017 at 3:17 PM, Frank Staffa Jr.kb2cwn@yahoo.com wrote: Hello everyone. I just purchased a M2 leopack antenna system and I was reading about different coax cables to use for low loss. Since I am mounting the antenna only about 10 feet off the ground, 50 foot will be enough to go into the shack. I wanted to purchase RG8x but read that the best way to go is with LMR400. What I dislike about it is that its much wider and very stiff, and will make it difficult around bends. I also have the Az/alt rotator which I will have to loop each antenna to have enough for turns. Any other suggestions out there for an alternative to LMR-400?Thanks Frank KB2CWN
Sent from Yahoo Mail on Android _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
ARR. Not cheap. They do fix them reasonably. Great to deal with. DEMI if you've got the SMT skillset.
On Sat, Feb 18, 2017 at 8:29 PM, Frank Staffa Jr. via AMSAT-BB amsat-bb@amsat.org wrote:
Well, I have spent a good portion of the day trying to find preamps for my M2 leopack. I read that at the very least putting one on the 70cm antenna will help a lot with the receive. But, I just can not find any. Most of the names I came across must have went out of business because their website are no longer in existence. Any suggestions out their from you season operators out there? The ones that I got last post I couldn't find. Thanks
Sent from Yahoo Mail on Android
On Fri, Feb 17, 2017 at 3:17 PM, Frank Staffa Jr.kb2cwn@yahoo.com wrote: Hello everyone. I just purchased a M2 leopack antenna system and I was reading about different coax cables to use for low loss. Since I am mounting the antenna only about 10 feet off the ground, 50 foot will be enough to go into the shack. I wanted to purchase RG8x but read that the best way to go is with LMR400. What I dislike about it is that its much wider and very stiff, and will make it difficult around bends. I also have the Az/alt rotator which I will have to loop each antenna to have enough for turns. Any other suggestions out there for an alternative to LMR-400?Thanks Frank KB2CWN
Sent from Yahoo Mail on Android _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb
participants (11)
-
Frank Staffa Jr. -
Jeff -
Jim Jerzycke -
John Toscano -
Mike Seguin -
mvivona＠yahoo.com -
Norm n3ykf -
Paul Stoetzer -
Scott -
Selwyn Cathcart -
Zach Metzinger