Handheld HAM radio, roof antenna, & length of COAX

[SoCalSearch]

Good evening everyone!

Brand new to HAM and getting everything setup. I just purchased a Diamond X50A antenna (

~ X50A Dualband Base/Repeater Antenna Diamond® Antenna

) and will be mounting this on my chimney. I also purchased a 150 foot run of ABR Industries (2213A-PL-150) RG213/U (Mil-Spec)Coax Jumper w/ PL259 Ends.

I'll initially be setting this up to my Yaesu FT3DR handheld radio (

Welcome to Yaesu.com

) and possibly be purchasing a FT-400 in the future, but that will be a while.

I purchased the 150' coax because I did a very rough estimate of the run I need at home and I asked the gentlemen at the store if I will hjave any issues with loss of signal. They said I would not, but I wanted to come on here and ask. If I do run the risk of losing signal, I'll do a much more accurate measurement of exactly the length I need. If it's no big deal, I'll just use the 150'.

Thanks and I appreciate the help!

 

[prcguy]

150ft of RG-213 has roughly 2.8dB loss at 150Mhz and 5.2dB loss at 450MHz, I think that is significant and should be reduced. 3dB loss would be loosing 50% of your signal and 6dB would be loosing 75% and you are not far from that on 2m and 70cm. A better choice would be LMR-400 with about 1.5dB loss at 150MHz and 2.7dB loss at 450MHz. 150ft of coax is considered a long run for VHF and UHF and needs some special consideration or shorten the run. Shorten it a lot if you can.

Where in So Cal are you? What store said it would not have any issues with loss?

 

[mmckenna]

That's lot of coaxial cable.

All cable has some amount of loss. Lower grade cables have more loss. Losses also increase as frequency increases. More cable + high frequencies = more loss.

So, 150 feet of RG213 at 445MHz (70cm band) is about 7.5dB of loss, or about 83% of the signal lost to the cable. That works both ways:
83% of the signal that your antenna receives will never make it to the radio.
At 5 watts on 70cm, about 0.8 watts will actually make it to the antenna.

Sounds like the guy at the store either didn't know what he was talking about, or was more interested in selling you a bunch of cable.

Getting the radio and antenna closer together will help a lot.
Using higher grade coax will help if you can't.
But it'll work, just not really well.

Antenna gain is going to help you a little bit, but not much.

You can play around with the coaxial loss calculators on line to try out different lengths of cable, different types of cable, etc:

Coax Loss Calculator | KV5R.COM

 

[K4EET]

prcguy beat me to my reply with the numbers. LOL! But like prcguy, I have some real concerns over somebody telling you that there were no issues with loss of signal. I cannot believe they said that unless they are just trying to make a sale with no concern for the customer's resulting system. That sale would in effect all but kill the system.

I can give you some East Coast suppliers of antenna systems but I'll let others chime in with hopefully some West Coast suppliers that actually know what they are talking about AND care about the customer's resulting system. You did right by bringing your proposed design here to radio reference. Lots of knowledgeable folks here that can help to keep you from having a bad experience.

73, Dave K4EET

 

[SoCalSearch]

I am so glad I came to this site before I took everything out of wrapper and installed it! This would have been a disaster. Everyone in the store was very helpful so I know they were not trying to over sell me. I could have misunderstood their answers because I am so new, but I was under the impression there wouldn’t be an issue with 150’ run.

As the previous poster mentioned about the LMR-400, is that the highest quality I can get, or is there something better?

Also, I am pretty sure I can relocate the antenna and get a run of about 50’

Regardless, will the connections always come with the PL259 ends?

 

[K4EET]

With the better coax, you might want to switch to "N" connectors. Your antenna would then be this one:

Diamond® Antenna ~ X50NA Dualband Base/Repeater Antenna

I'll let the others chime in with the answers for the feedline.

73, Dave K4EET

 

[K4EET]

<snip> I am pretty sure I can relocate the antenna and get a run of about 50’ </snip>

If you can go with 50 feet of feedline, that is definitely the better of the two choices. Will you still have the same antenna height above ground level (AGL)?

73, Dave K4EET

 

[SoCalSearch]

I believe I can keep it in the exact same location. Is LMR-400 considered the best coax? Who is considered the best supplier of coax cable so I can review their website and find a 50’ run of cable with PL259 connectors.

I also plan on possibly purchasing a Yaesu FT-400 in the future and that uses the PL259 connector.

 

[K4EET]

SoCalSearch, I buy all of my antenna system parts, those that go between the radio and the antenna, from the RF Connection in Gaithersburg, Maryland. They know their products and care about their customers. Their website is:

Home | RF Connection

rfconnection.com

Now that you have dropped back to 50 feet of coax, that changes the equation by a factor of three. So using the numbers given in the above posts, the loss for 50 feet of RG213/U becomes 2.5 dB and the loss for the same length of LMR-400 becomes 1.4 dB. So we see that the LMR-400 coax has about half the loss as compared to RG213/U. As for connectors, the N connector is better than the UHF connector. If it were me installing this antenna system, I would get the Diamond Antenna with an N connector. For the 50 feet of feedline, I would go with the Times Microwave LMR-400 (avoid any knock-off products) with an N connector on one end and a UHF connector on the other end. Keep in mind that the bending radius of LMR-400 is around 3 to 4 inches (to be on the safe side). Here is the specification sheet.

https://www.timesmicrowave.com/DataSheets/CableProducts/LMR-400.pdf

Now the other thing that has not been discussed is grounding. That is an absolute must! Building Code also requires it. I need to find another thread that has a good discussion on that topic. Once I find it, I'll post a link to it in this thread.

73, Dave K4EET

 

[JoshuaHufford]

I would suggest terminating the end of your coax (part coming into your house) with a male N connector, then use a short jumper of more flexible coax with a female N connector, then whatever other connector connects to your radio. As your needs and radios change this will give you more options down the road. The lower the loss of coax the stiffer it usually is, and you don't want to connect that directly to your radio.

Yes there are lower loss coax cables than LMR-400, there is LMR-500, LMR-600, on up, then you get into hardline etc. Is that better? Can be, depends on your needs. I would suggest installing what is practical for your budget and installation, get the lowest loss coax you can afford and install, keep in mind bends will become harder to do and will require a larger radius the lower loss (larger) coax you go with. I did a run with LMR-600 a few months back, it was quite difficult to work with even in a large open area.

Also, if you go with an LMR coax, get actual Times, not a knock off, I've only ordered from this place once, but I had a very good experience with them and their pricing was really good.

CUSTOM CABLE ASSEMBLY | WiFi and RF Expert

NEED A CUSTOM CABLE? WE MAKE MOST OF RF CABLES AVAILABLE ON THE MARKET TODAY. CLICK HERE TO CREATE YOUR CABLE NOW

wifirfexpert.com

Spend the time and measure your run, keep it as short as possible. Also don't forget about grounding properly, that is a whole different subject better suited for a different thread.

Another subject is proper waterproofing your connections, a lot of great info in many threads on that subject on here.

Running quality low loss coax now may save you the need to re-run the coax down the road if you get into scanning ta higher frequencies, and your current plans will work much better now.

 

[SoCalSearch]

Sir, I cannot thank you enough for your input. I am going to do exactly what you suggest.

Would it make sense for me to just order a 50’ LMA-400 run with Type-N connectors on each end, then I can get two different jumpers one for my current radio, and one for the radio I plan to purchase in the future (Yaesu FT-400)?

Finally, where is the best outlet to purchase Times Microwave cables?

Thank you very much, this has been an incredible learning experience and probably saved me hours of troubleshooting something that would never have worked.

 

[K4EET]

SoCalSearch. here is the thread about Antenna Grounding:

Antenna Grounding?

I have installed a Discone antenna on my roof. Am I supposed to earth ground the mount frame on the antenna? The mount is a TV antenna mount if that matters.

forums.radioreference.com

 

[K4EET]

JoshuaHufford's suggestion on the jumper at the radio end is also good. You pick up a few tenths of a dB more loss due to the additional connectors but that will not kill the antenna system like the 150 feet of RG213/U would have.

As for the future radio that you are referring to. I believe that you are talking about the Yaesu FTM-400XDR:

Welcome to Yaesu.com

We are all glad that you are getting the help you need.

73, Dave K4EET

 

[prcguy]

SoCalSearch, what part of So Cal are you in?

Sir, I cannot thank you enough for your input. I am going to do exactly what you suggest.

Would it make sense for me to just order a 50’ LMA-400 run with Type-N connectors on each end, then I can get two different jumpers one for my current radio, and one for the radio I plan to purchase in the future (Yaesu FT-400)?

Finally, where is the best outlet to purchase Times Microwave cables?

Thank you very much, this has been an incredible learning experience and probably saved me hours of troubleshooting something that would never have worked.

 

[wowologist]

One question, have you even tried just the included antenna on the HH? I know being a new ham you walk into the wonderful alphabet store and think "I'll just ask" ....we'll take it from experience...used car salesmen are novice compared to these guys. Wallet biopsy - just say no. Here in the SF Bay area I can hit many repeaters with just my HH and some that have great vision and are well installed - I can hit with 1w @ 22 miles away with full quieting from inside my house here in the east bay. You can always try a site/app like repeaterbook.com to geo locate boxes around you. gl and welcome to the hobby!

 

[SoCalSearch]

I am located in Sherman Oaks.

 

[SoCalSearch]

I don’t have my license yet, but I had my friend come over who has his and he tested and we hit a ton of repeaters. The particular room in my house is near two bathrooms and it interferes a LOT with my reception. When outside no problem, so this is the main reason why I want to add the antenna and to be honest, it’s a lot of fun tinkering around and learning new things. I think all of this stuff is really neat and wish I got into it sooner.

I plan on using APRS for hiking and integrating this into a custom map online so people can watch me hike the hills and follow my progress. Should be a lot of fun!

 

[prcguy]

Aah, a "Val". If you ever get down near the beach I probably have a 50ft chunk of LMR400 with connectors you could have.

I am located in Sherman Oaks.

 

[SoCalSearch]

That is really nice of you!! Would love to hear what kind of equipment you have since you’re local and what kind of repeaters you hit around here.

 

[prcguy]

That would be a really long post, but keeping in line with your posts I do have an FT3DR and and FTM-400DR and use them here and there. I can get into most repeaters from Mexico to your end of town and out into the desert but don't use all that many repeaters on a regular basis except the ones humming away in my garage.

That is really nice of you!! Would love to hear what kind of equipment you have since you’re local and what kind of repeaters you hit around here.