kidphc
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Posts posted by kidphc
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I haven't had to. But regularly follow AARL wilderness protocols when out in the woods.
Especially, around George Washington National Park in Wva. Dad lives close by and if you aren't right by a town, you often don't have cell service.
Really wish all radios followed NEMEA standards for GPS data.
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Depending on where in Florida, you are going to have good to incredible GMRS repeater service.
Personally, I would be looking at no less then a dual bander with dual recieve radios.
The 578 like the 878 are a dual recieve but only have one true transmitter. Which may effect how you would use it. I haven't seen away to unlock the 1000g to do anything but recieve on 2m. Although the amateur version of the radio, I have seen a software/firmware hack opening up the GMRS frequencies. The second problem becomes the antenna, since most dual band/triband radios do a crappy job of trying to do both GMRS and 2m. One of the two has crappy performance, although sometimes JUST acceptable.
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Which service are you going to use more?
Not that I cadone it, but it is much easier to open GMRS frequencies then the other way around on most radios. Ie CAP modding a ham radio.
Especially, if you are positive you are going to get your ticket again. It's about a 1000x (times) easier now a days since the cw requirement is gone now. Hell might as well get your general. 578 will be great if you are going to get into DMR. They have new model comming out that is essentially a 578 brick where you can option out the blue tooth mic.
Personally, running a FTM400XDR and a Motorola XTL 5000 (UHF). The XTL5K, is going to be replaced with a Harris 100m. So I can retain Gmrs/p25 capabilities on one radio and 2m/70cm with aprs on the other radio. The only real things the Harris brings over the XTL, is VHF and 700/800. The low band VHF amplifier is impossible to find, so that will be receive only.
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You can do either.
If you are in an heavily used area or have multiple repeaters on the same frequency. Then I would suggest using the output tone. Even then always open squelch (or use monitor) to verify input frequency is not in use, before transmitting.
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Oh.. yea I agree. Listen to aprs frequency in a dense area.Until you have a dozen or so stations doing it on your channel. Then even a short data burst at frequent intervals is going to be irritating.
What I was referring to was the amount of data that can be sent. Especially, something like FT. Damn symbols rate caps, lol
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Don't know what it is. But a one second date burst is quite small.I’d be interested to know what the character limit would be. Depending on the “data mode” it could be enough to send a reasonable message. 1 per 30 seconds isn’t a terrible limitation
Maybe 1/2 of a standard aprs beacon without additional text?
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Kinda tough.
Data burst can't be longer then one second.
"3) Digital data transmissions must not exceed one second in duration."
Can't have more then one data transmission inside of 30 seconds.
"(4) Digital data transmissions must not be sent more frequently than one digital data transmission within a thirty-second period,"
Data transmissions have to be manually activated. The devices can not store and forward packet modes for data.
Sounds like they don't want you to. Realistically, speaking even an aprs packet is 2.5 seconds long. Ft's' being streams and automated (well kinda), looks like verbiage was put in to stop exactly that kinda of thought.
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Any antenna even a no groundplane antenna, hate that wording. Will perform better with a ground plane. So depends.
Grounding is for static electricity build up from the antenna and coax. I have antennas in the attic but due to dust blowing over the coax I put arrestor in. For a tremprory install not a necessity but nice. Be aware of this when off roading to a dry dusty area though, especially as winds pick up. No need to fry a radio. Then even an grounding spike would be nice. With that being said a lot of hams on sota/pota (summit/parks on the air) don't even ground.
Personally, for your type of setup. Especially, for solo hill type of excursions. I would build a tape measure yagi ( even though about tv rabbit year yagis, to be multi frequency resonant). Guess it depends on how the mast is secured and what it is. Betcha you it's a harbor freight flag pole, recommend all the time as permanent or portable mast, can't beat the $50 cost.
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What you say is empirical. Unfortunately, a lot of factors come into play.That's essentially all that I am trying to sort out. I have both this discone as well as a yagi with a perfect 1.0 dip RIGHT at 467.55. I use a repeater about 20 miles out and I can hit it with both types of antenna. The discone comes in a bit fuzzy and the occasional drop out. The yagi hits the repeater full quieting. It's just that I have to physically go out to my mast to rotate the yagi in the various directions that I'm aiming to target. I have a repeater that's actually excellent in my area that I'm fortunate enough to be 2 miles away from, which is where I stick around on mostly and for that my discone hits that rock solid and full quiet..
Additionally, the discone sits atop my mast about 21ft high, and the yagi is further down the same pole only about 12 feet up, and it still gets out 30+ miles fully quiet with about 7.5 watts.
I'm just doing some anecdotal testing of the antennas I have access to. Seeing first hand how antenna design, decibel rating, and lobe patterns really do translate into empirical results. I didn't know much about this end of radio stuff beyond a year ago despite having been involved with it since a young age. Just sort of going down a rabbit hold of antenna gain and the capabilities that can be achieved on the antenna side of things even with low power by paying attention to how things radiate.
I think a lot of people get hung up on sheer wattage power, when your radiation efficiency is a far bigger factor.
The theory is just a start. Antenna theory isn't magical, it's physics. So no super bending the laws to get magical more "farz" from similar designs. We give up some here for more there. Unfortunately, advertising from the companies selling us stuff obfuscates a lot of the truth, and the internet adds more.
Same thing with the gear we use. X vs y company. How much it cost vs quality. Does it make a difference? Yes/no. Hard to explain or quantify even in person.
Glad you are testing with things and coming up with your own answers. Knowledge is king.
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I get it. Other designs have similar issues. But let's be truthful here, we aren't going to be talking skip zones often with uhf. For me almost the same guys on 2m or 70cm ssb. Well minus some tropo.It matters a good bit on VHF and UHF but you desire a more shallow angle. Every bit of RF that is radiated into a wasted direction is inefficiency towards your "fars capability". Good 9db gain omni verticals will squash the radiation donut into a thinner pattern in vertical diameter. My suspicion is that the radiation pattern from this discone is apple-shaped.
For HF, that's fine to shoot your RF up at a high angle for ionospheric reflection. But as we know, UHF is just going out never to return.
Yagis are another example.. Sadly, they have a crap ton take off angle. Tons of the energy is lost up high and into the ground So much so I was trying to design a workable cubic or quad-cubic antenna, by design they are flatter and tighter in radiation angles.
But since a discone, is considered an omni-directional antenna, it is basically a sphere. So yes, 1/3 of the radiation is up top, is in an undesirable angle. So is up to the lower 1/3.
Basically, don't sweat it too much
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From what I get.Yes, the antanna can take the RF input and has perfectly adequate SWR, but my question is what that radiation pattern is like.. If the radiation take off angle is such that an equal about of it is radiating at 1 o'clock upwards as it is 3 o'clock, that's not very good.
my question is if that's the case? Unity gain?
The pattern is close to omni directional radiation pattern like. They will be varying lobe gain values, small fingers.
They harder thing to figure out is gain values for a particular frequency. Reading it is between 1.2-2.3 dbi or so.
The gain problem is only a problem if you are a ham might cause some pain doing the rf exposure studies, that we are required to do now. Which i know really affects hf users more than vhf/uhf/shf/ehf.
Also for these frequencies I not sure take of angle is going to matter especially with an omni directional pattern.
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You can transmit on discones. Especially, if the swr is acceptable in the transmit range.
They are really optimized for recieve. So mileage would vary. The transmit radiation pattern are often not very good because of this.
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Exactly as Wrxb215 said.So with that being said, what would be the advantage of a yagi with 7Dbi that is directional vs an omnidirectional vertical that is 7Dbi?
Basically, since the cone is narrower then the omni directional antenna's pattern, you can steer the yagi in the direction you want to hear. Effectively nullify any RF interference (ham call it qrm) or noise, well at least lowering the level. If you radio fox hunt generally a yagi, even low gain ones are helpful in pointing you in the direction. They are often coupled with attenuators, you will often see the guys flipping the yagi on the side to attenuate it further. Opposite to the suspects polizaration. To make reception weaker and isolate to a finer degree heading.
Yagis generally have a higher gain level than their vertical/horizontal counterparts due to the squishing of the pattern. You generally switch from length of the antenna space to the swing space a yagi needs. Plus you can stack yagis onto arrays, Which will increase their gain levels.
So comes down to do you need spray gun (coverage) or an ultra fine pinstriping paint brush (detailed control).
Each have their pros and cons.
Just an fyi: the amateur (hams) that are into eme and moon bounce (considered weak signal due to the distance). Use stacked arrays with high gain levels and 1500 or so watts of power. To get as much signal to where they want it instead of scattering it around them.
Same with the guys that work satellite.
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We have an owner out here, he has about 6 heavily used repeaters. Equipment for way more.
1. He has the resources.
Ie. Equipment, knowledge and the network of people (for repeater sites locations)
2. It's a hobby for him
Originally it was set up for the Red Cross, as the primary user. He has it open for everyone licensed although it isn't published. We all acknowledge, should the Red Cross need them, we give way.
Some people do it so they can. Some people do it because they feel they are helping the community.
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I like to think of antennas like and adjustable flashlight.
Omni kinda like a donut from the side 3d wise. It would be like having the open without a shroud like a latern.
As you you increase gain. The beam becomes flatter and flatter into a disk.
When you speak of yagis you have put the shroud on and focusing a beam. A beam that shoots more light out the front but spits some out the rear. Hence why yagis have a front to back ratio for gain. There is a technical expectation, and some design that focus more forward? But I am skipping that.
All antennas create lobes so generally, they measure the strongest lobes.
The attached with the donut is omni directional. The phallic looking graph is the yagi.
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Forgot about slot antennas.YOu are going to want to put an antenna as high as possible for best performance.
Since you have an HOA and I am going to assume that you have approached them for a variance on their by-laws and failed, the next and most reasonable option is an antenna inside the attic space. This will work reasonably well if you don't have a metal roof. Obviously a metal roof will significantly limit your ability to get RF through it.
Another option is a small dish for TV. But be warned that you will need to research the federal regulations allowing for a small dish or off air antenna for folks that are in an HOA and their by-laws 'limit' that. Due to it being a path for emergency communications, the FCC has mandated small dish and off air antenna's be allowed in all instances. But you are going to need to get copies of those federal regulations in hand and present them to the HOA for review before doing anything else. They will no doubt what to verify it before making a ruling. And depending on the caliber of people running your HOA, they may or may NOT take well to being forced by anyone including the federal government to grant a variance. At the point you basically role up the rules like a newspaper and slap them in the face with it. They WILL crawl up your hind parts and file for a new address in there. They will watch you like a hawk, making sure to enforce EVERY other regulation and by-law they have on the books. And of course fine you as often as is possible until you sell out and move. But it's an option, so I figured I would mention it. After all the HOA isn't going to know what antenna is for what.
But, first option is filing for a variance with them and seeing if you can put up something on an eve of the roof on a small mount.
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Very good antennas. Ed is a professor, he explains alot of the theories in YouTube videos.This is the one I am going to use. Its only 3 ft long I doubt anyone will notice it if i put it on the back of my house. I have also read of people putting this in their attic as well but, Im very new to the GMRS world so I may be completely wrong.
https://edsantennas.weebly.com/
Keep in mind follow the directions closely. He has accounted for the pvc tubing, which is a bit specific. Personally, 90% of complaints of the antenna come from using the wrong pvc.
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You raised your hand. Because that is the only way to change some absurd laws.While you are avoiding detection by the neighbor who does not like you ...
HOAs are fun !!! ...
I also like to point out "better" HT antenna alternatives such as Slim Line 465 MHZ (smileyantenna.com)
That one got me into our local repeater when the stock antenna failed.
However, there are other HT antenna options and somebody else might have a different favorite.
Back to preparing my HOA board meeting (coming up on Tuesday) ... why did I have to raise my hand ?!?
My birdhouse random wire hf bird perch antenna and slim jim in electrical tracking inside the house salute you.
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You could paint and hide, base antenna, or slim Jim's in trees.
If you are a bit from the road or have trees that kinda hide you roof line. You could use a slim mobile antenna, and a groundplane nmo base mount to the eaves of your house.
Me I am using a combo of a ham 2m/70cm antenna in the attic and a mag mount on my ac.
I do have home brew gmrs yagi and 2m/70cm yagis that will go in the attic. Whenever I get my lazy butt around to it.
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Have you tried to reach out to amateur clubs locally? Texas seams to have a healthy group of nice amateur radio operators.
They probably have spare repeater hardware, duplexers, cabling and sites that can be used. As well as the know how. As well as some funding.
Most of amateurs are willing to talk to anyone about radio, irregardless of the service.
I say most, because well no matter what hobby there are always the aholes.
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Nope, no way to get it out of range. The filtering is awesome.. but it's too tight. The guys that took it apart said it wasn't worth it. They guys I was with, is where his conversation came from.I thought I saw one thread on cobbling together an amplifier/filter set on RR. I'm not exactly interested in transmitting though, but if VHFLo was available to listen, I would like too listen.
If only someone had a way to expand the VHFLo to 6 or 10 meters.......
They said they might be able to hack the software, but it would probably damage something in the radio very shortly. After spending 5 minutes with them talking I gave up.
Of course, what do these guys care. They are running around with full apx setups in their trucks. One of them a volunteer fd, setup his personal f350 like a command radio truck. Shit you not.. looked like 30k in radio gear alone.
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It's only good for really listening. The harris low band amplifiers are terribly expensive and incredibly difficult to find.Yes, I have terminators for both unused ports. It powers up and cycles through channels and zones.
I'm still undecided if VHF low is worth doing anything with. I don't see it being used in Ohio anymore, for anything. I also don't want to deal with another antenna.
One of the group of friends I have about 6 of the radios. They also have several vhf lowband commercial repeaters. They are intrigued by setting a lowband network from Shenadoh up to New York. They have been trying to figure a way to get an amplifier to work. Btw.. Most of them are local FD, some at the Homeland Defense regional level. So if they an find it they would of.
Primary problem, is the output for vhf low is a ridiculously low . 9mw.. which means it needs to be amped up to 1-2 watts at least to work with any other amplifier. But eww on an amplifier to feed another amplifier.
Secondarily, no low band vhf public systems minus a handful of municipal pd stations around here. Frequency range is only 33-48 MHz. Outside of ham and cb, so unless you have a commercial license for the band, then useless. Good news is band is emptying out so you can apply for one easily.
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L3Harris XG-100M
in Amateur Radio (Ham)
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