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Author Topic: This noob needs help  (Read 545 times)

OUTY565

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This noob needs help
« on: March 17, 2023, 10:38:29 PM »

Hello, I am very new to ham and am working on getting my license.  My plan is to use ham in combination with GMRS if need be for SHTF to stay in contact with some nearby family.  I do not plan on turning this into a hobby or something to tinker with, so the simpler the better.

My current plan is to utilize the below j-pole antennas for each ban attached to my chimney on my two story house.

https://www.jpole-antenna.com/shop/2-meter-break-a-way-j-pole-antenna/

https://www.jpole-antenna.com/shop/462-mhz-land-mobile-gmrs-j-pole-antenna/

I plan to have the power supply and transceiver mounted on a piece of plywood that would go in some sort of pelican type hard case.  I could then take it out of the case and connect the coax to the transceiver when I want to use it or mess around with it as this would not be a permanent setup.  That being said, I have the following questions:

1) Can both the 2 meter and GMRS antennas be mounted to the same chimney or do they need to be separated?

2) Are there any issues with the coax lines from the two antennas running down/into the house next to each other?

3)  Do the antennas need to be grounded against lightning protection even though they would be attached to a brick chimney?

4) If I were to attach a section of EMT pipe to the chimney to use as a mast, then would I need to ground the antenna and the mast?  If so, how would I do this?

5) How would I go about grounding the coax lines?  I've seen lightning arrestors be used but am unsure of how to do it.

6) Would I need to do anything special with the ends of the coax inside the house when they are not connected to the transceiver, or can they just "dangle" there?  Where they would come inside the house would be by other electronic equipment such as my router, would this be an issue?

One this I've noticed in researching some of this ham stuff online is that there is not a lot of straightforward answers which is pretty frustrating, so I'm hoping to find some answers here.

Thank you for your help with this.
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G4AON

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Re: This noob needs help
« Reply #1 on: March 18, 2023, 01:25:30 AM »

Those antennas are pretty lousy on three points:

They are shown taped to a mast, you will need mounting clamps.

The connection is open to the weather, it will need a generous coating of liquid electrical tape (rubber dissolved in strong solvents), with an over wrapping of tape.

J-pole antennas need an effective choke on the feeder near the feed point. A few turns of your coax feeder on a short piece of 2” plastic may suffice. Without a choke the feeder will radiate and may cause interference to nearby equipment and will pick up noise from household appliances.

There are construction details of these “plumbers delights” in many antenna handbooks. You can easily make one yourself. For temporary, or portable use, the “Slim Jim” type can be easily made from ribbon cable. I use one for 6m, but dimensions for 2m ones are on the web.

Regarding mounting, if you use two chimney lashing kits, mount each one on a separate “TV shop” antenna mounting mast on each corner of the chimney.

Most of us prefer to use a fibreglass encapsulated antenna, such as the dual band (2m and 70cm) Diamond X50, or similar. Ignore the manufacturers claimed gain figures, they are exaggerated and are often gain over a 1/4 wave antenna (roughly 3 dB more than gain over a dipole, the usual practical reference).

https://www.qsl.net/g4aon/j-pole/

Besides an SWR meter to check/adjust an antenna, a simple common mode current meter to check how effective that  feedline choke is working is an easy to make project. To use one, transmit while sliding the meter along the feeder, you should not be able to measure any current. This article shows how to make one. They are typically accurate from 160m to 4m (mine is +/-20% over that range) and are usable to 2m, probably not to 462 MHz though. See: http://www.ifwtech.co.uk/g3sek/clamp-on/clamp-on.htm

73 Dave
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N8TGQ

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Re: This noob needs help
« Reply #2 on: March 18, 2023, 06:18:03 AM »

 If your radio use is going to be intermittent, consider using roll up antennas you can roll up and store with the radios. That way, a lot of issues such as mounting, grounding and lightning protection are lessened. I used 2 antennas from Eds antennas. That way one antenna gave me 2 meters and 440 ham bands, and another gave me the MURS, FRS and GMRS bands.

 I used a 10' section of 1" PVC slid into a 10' section of 1 1/4 PVC for a mast. They overlapped about a foot and I secured them with a 1/4' bolt. With the bolt removed, I could slide one inside the other for storage. I put a "tee" at the top, and slid a 2' dowel thru it to hang the antennas. I didn't have any problems with the 2 antennas that close, but I was only using one at a time. I used  one of those green T-posts used for fencing to hold the mast upright. I didn't use guy ropes, but it was only up for a week at a time maximum. I did end up using the mast to hold up the end of a wire dipole later, and it was up permanently for about 10 years. At these frequencies, use good quality coax to minimize losses.

 Without using repeaters, don't expect much range, even with 50 watts and high antennas. I was lucky to get 15-20 miles. Directional, gain antennas would improve that, but that means stronger masts, guy ropes and headaches.

 Understand that unlike GMRS, each person transmitting on ham radio has to have their own license. There's no immediate family "loophole" to make them legal under your license.

 After experimenting for a few months, we went with yard sale CBs and homemade dipole antennas tuned to the band. They worked about the same, with no license hassles. The antenna would still hang on my mast, or I could hang it from a tree or building. There were a lot more people you could get info from, and sometimes I made contacts a thousand miles away.
« Last Edit: March 18, 2023, 06:20:22 AM by N8TGQ »
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K5LXP

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Re: This noob needs help
« Reply #3 on: March 18, 2023, 06:21:44 AM »

You're going down this road like j-poles are the only antenna solution.  What about the idea of an inexpensive commercial dual band vertical (already built, tuned, weatherproof), put it up and you're done.  Not to dismiss the idea of j-poles, I have and use a few but they're a tinkerer special, and you've stated with good reason this isn't your mission. For something intermittently/randomly used with equipment not normally connected to it, I wouldn't bother with lightning protection.  You could bond the mount to service ground if you like but I wouldn't obsess about it.  Put something up and try it, if you decide to make it more than temporary you can decide what protection measures if any make sense.  To TGQ's point, I use a twinlead j-pole when camping, hauling it up 50' or more into available trees.  A basic dual band mobile mag mount would also be a good option for mobile, portable and even on the roof of the house, stuck to an existing steel fixture like ducting, flashing, gutters.

Mark K5LXP
Albuquerque, NM
« Last Edit: March 18, 2023, 06:25:32 AM by K5LXP »
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OUTY565

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Re: This noob needs help
« Reply #4 on: March 18, 2023, 09:11:53 AM »

Thank you everyone for the feedback so far!  I'm not completely sold on the j-pole; it just seemed a decent option for the price based on the limited information I could find/understand.  I do like that diamond x50.  Seems reasonably priced with minimal hassle.

I have thought about using those roll up antennas as an option to keep in the case to take with the radio to make it portable.  However, I would still prefer to just mount one to the chimney, so that when I have time to mess around with it or truly need it, I can just connect the radio and be good to go.  If I used the chimney lashing kits the top of the antenna would get to about 23' off the ground. 

My utilities come into the house at the complete opposite end, so I don't think bonding it to the ground rod over there is an option.  Is a separate ground rod by the chimney an option or even necessary?  What about a lightning arrester for the coax?  Back when everyone had TV antennas on their roofs were these even grounded, or where they just mounted up there with the coax line simply fed into the house?
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WA3SKN

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Re: This noob needs help
« Reply #5 on: March 18, 2023, 10:37:53 AM »

" My plan is to use ham in combination with GMRS if need be for SHTF to stay in contact with some nearby family.  I do not plan on turning this into a hobby"

Well, ham radio IS a hobby.  What is wrong with just using a phone?
So my question is "what are you TRYING to do?"  How can we help?

-Mike.
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N1AUP

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Re: This noob needs help
« Reply #6 on: March 19, 2023, 12:53:39 PM »

Thank you everyone for the feedback so far!  I'm not completely sold on the j-pole; it just seemed a decent option for the price based on the limited information I could find/understand.  I do like that diamond x50.  Seems reasonably priced with minimal hassle.

I have thought about using those roll up antennas as an option to keep in the case to take with the radio to make it portable.  However, I would still prefer to just mount one to the chimney, so that when I have time to mess around with it or truly need it, I can just connect the radio and be good to go.  If I used the chimney lashing kits the top of the antenna would get to about 23' off the ground. 

My utilities come into the house at the complete opposite end, so I don't think bonding it to the ground rod over there is an option.  Is a separate ground rod by the chimney an option or even necessary?  What about a lightning arrester for the coax?  Back when everyone had TV antennas on their roofs were these even grounded, or where they just mounted up there with the coax line simply fed into the house?

I have a Diamond X50 at about forty feet.  It's connected to my shack with LMR-400 coax.  I attached a copper wire to the nut on one of the mounting ubolts, and ran it down my mast to a 10 foot ground rod pounded into the ground.  I do not ground the coax.

Now I live 1000 feet above sea level here in Central Mass, but I can hit Mt. Washington, Mt Greylock, Saddleback mountain, and most anything else within 60 miles.  Mostly on 5 watts, but rarely more than 25.  If I put up a yagi, I could do even better.
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KA4WJA

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Re: This noob needs help
« Reply #7 on: March 19, 2023, 10:13:36 PM »

OUTY565,
We don't know where you are located, but since you mention "GMRS", I assume you're in the US?

I'd like to help you out / save you some money and effort.
And, the good news is it's doubtful you'll need any ham radio antennas / ham radios, at all!  :)
(actually ham radio is opposite of what you need for your application....and what you do need is probably less expensive, too.)

Your application here is best suited for MURS, CBRS (27mhz Class D Citizens Band / CB Radio), or GMRS, (and maybe even FRS, for short ranges), but the Amateur Radio Service (ham radio) is the least suited for your application!  :(

https://www.fcc.gov/wireless/bureau-divisions/mobility-division/multi-use-radio-service-murs
https://www.fcc.gov/wireless/bureau-divisions/mobility-division/citizens-band-radio-service-cbrs
https://www.fcc.gov/wireless/bureau-divisions/mobility-division/general-mobile-radio-service-gmrs
https://www.fcc.gov/wireless/bureau-divisions/mobility-division/family-radio-service-frs

FRS (for very short-range comms) and CBRS / 27mhz CB, are both designed for personal/family communications, without licensing (as well as MURS).  This allows personal comms without need for public infrastructure, etc., nor needing any public concern, assistance, etc.  This allows personal "selfish" comms, to coordinate, assist, and protect yourself, and family, without care for others.


GMRS and MURS can also do the same, although the range of GMRS may depend on repeaters (infrastructure) and/or decent antennas at all of your family's locations, and as GMRS freqs are shared and whether using repeaters or simplex, you may find others using "your pre-defined" freqs, that could interfere with your comms (of course this can happen with almost all radio comms).

MURS is VHF simplex only (no repeaters, no infrastructure), with radios limited to 2 watts, but no restrictions on antennas...so, depending on what comms range you need, MURS may be your best choice here! (and, fyi, MURS is very lightly used, so doubtful you'd have any interference / shared users, as might be the case with GMRS....oh, and MURS is also "license-free", like CB Radio....but unlike GMRS)
But, in general, MURS and GMRS, etc. does not require you to have any concern for others, nor provide any public service, etc.

Some MURS info:
Quote
Connecting a MURS radio to an external antenna can extend the range to ten miles or more. MURS stations are not allowed to be interconnected with the public switched telephone network. A station identification announcement is not required to be transmitted.

https://www.fcc.gov/wireless/bureau-divisions/mobility-division/multi-use-radio-service-murs
https://www.fcc.gov/wireless/bureau-divisions/mobility-division/citizens-band-radio-service-cbrs
https://www.fcc.gov/wireless/bureau-divisions/mobility-division/general-mobile-radio-service-gmrs


The Amateur Radio Service (ham radio) on the other hand, is specifically designed for selfless, public service communications, especially in emergencies (or as you wrote when the "SHTF")!
As well as being US Federal Law, it is also international law and codified by most western/developed (and many developing nations, as well) nations' governments.

 
https://www.fcc.gov/wireless/bureau-divisions/mobility-division/amateur-radio-service

Please read this here, it is the very first part of our US FCC rules, governing the Amateur Radio Service (ham radio):

Quote
FCC Part 97.1

97.1   Basis and purpose.

The rules and regulations in this part are designed to provide an amateur radio service having a fundamental purpose as expressed in the following principles:

(a) Recognition and enhancement of the value of the amateur service to the public as a voluntary noncommercial communication service, particularly with respect to providing emergency communications.

(b) Continuation and extension of the amateur's proven ability to contribute to the advancement of the radio art.

(c) Encouragement and improvement of the amateur service through rules which provide for advancing skills in both the communication and technical phases of the art.

(d) Expansion of the existing reservoir within the amateur radio service of trained operators, technicians, and electronics experts.

(e) Continuation and extension of the amateur's unique ability to enhance international goodwill.

As you can see, ham radio is not what you want here.

What you want is probably CB Radio and/or MURS, and/or GMRS (sort of depends on where you're located, the comms ranges you require, and your average terrain...if we knew that, we could be more specific).


So, I hope this helps you out.
Wishing you good luck and fair winds.

73,
John,  KA4WJA
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OUTY565

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Re: This noob needs help
« Reply #8 on: March 29, 2023, 05:01:58 PM »

Thank you all for your responses. I did end up going down the GMRS route and just got my application approved. I am able to hit a couple of repeaters near me one of which is about 30 miles away with a HT. I’m in the Midwest so my terrain is very flat and it’s suburban. I still would like to get some sort of GMRS base station setup to improve the range of the repeater goes down. The family and friends I want to communicate with are 5-6 miles away. Any suggestions for a setup?
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K5LXP

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Re: This noob needs help
« Reply #9 on: March 30, 2023, 05:05:35 AM »

5-6 miles direct (no repeater) is readily done simplex (direct/no repeater) but probably not reliably handheld to handheld from indoors.  A basic antenna like a quarter wave outside (even as simple as a mobile mag mount on a pizza pan or rain gutter) at each station would likely make this a solid link.  For 460MHz this is an antenna 6" long so not a huge issue to install or move about as needed.

Mark K5LXP
Albuquerque, NM
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OUTY565

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Re: This noob needs help
« Reply #10 on: April 01, 2023, 12:52:06 PM »

Gotcha.  So basically use mobile antenna and mount stuck up on the roof, run the cord inside and connect to a 40W or 50W mobile unit and power supply should be adequate?  Do I need to worry about grounding it or lightning protection?

Also, if i were to stick a mag mount on a roof vent, it wouldn't be sticking up at 90 degrees due to the slope of the roof.  Would this be an issue with broadcasting the signal?
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