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Everything posted by marcspaz
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Howdy!!! Welcome. This is strictly 'use at your own risk' and opinion based on my experience. So, I would hate to say it, but the antenna thing depends greatly on the radio you have. I have a diamond X50 repeater antenna on my roof and about 125 feet of cable to get from the roof to the basement. The BTech handheld I have (which is fine for the most part) doesn't create enough power to overcome the cable losses to trip a repeater that is less than 3 miles away, even though I can full-quiet the same repeater from the driveway. Also, it can't hear the repeater. So, the external antenna is not an option for that radio. BUT... The Yaesu HT I have can use the same cable and antenna to receive a repeater signal from 35 miles away. Plus, with 5 watts the audio is a bit scratchy, but I can get into that same repeater. So, if you have a high quality radio, get some RF9913 and an antenna like an X200 and you should be fine. It will cost you about $500-$600, but it should work. Sadly, I can't help with this one. I am a computer scientist by trade. The last thing I want to do when I am not working is get more screen time. All my radio comms are analog and OTA.
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I appreciate the flowers... but there are two problems. 1.) I spent 3 years studying electronic technology and engineering. I can describe electron flow to a 5 year old kid at a level they understand. Right now I could start writing everything I know/think that could possibly help in any one given situation, and may finish in time to watch my 3 YO grandson graduate from high school. And I'm not even close to the smartest guy on this forum. There is WAY to much information in my head to share all of it, I don't want to write it all down, and I have no idea what is important to YOU until you ask. 2.) The issue isn't to know when to lead. The issue is for the user to know what direction they want to be led. Then, I can help you 'if' I am qualified to do so. Enter forums... a place were people can come with specific questions and experienced people will try to help. Yes... ^^^ This. We are all here to help, learn and rag-chew about the tech. However, goals, limiting factors and aptitude of the person needing help, makes possibilities endless.
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I think the biggest problem is, there are too many opinions AND most new users don't even know "what" they want to do. For the most part, many new radio users don't know what tech is the correct tech for any intended purpose. Until they get in and find out something they like and figure out how it will suit their needs, we wouldn't even know what advice to give. I have tried to help, though. I actually have a published article I wrote about the pros and cons of each common service, what they could potentially used for, and just a really brief overview of the science behind it. It was focused around off-road communications, but applies to everything. I can always share it here, but I haven't due to potential bickering.
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No. UHF is a line of sight service. The tower will either have zero impact or (using a beam, etc.) absorb the waves. Ground absorbs UHV signals. The rest goes into outer space. You just get to talk to anyone from in front of you, to the visual horizon while the wave is on the way. We bounce UHF and VHF signals off of satellites (such as Earth-Moon-Earth) successfully because they are not grounded.
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In general, I like the idea. I would move the remembrance text under the photo and put your grid locator with your address. Then I would make your call sign larger and put the QSO info on the back.
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What are you looking to extend? HT use? Typically using a repeater that is open to the public doesn't require any special permission from the owner. Depending on your setup, they would have no way of knowing anyway. That said, cross-band repeat into another repeater is a massive PITA. You have significant delay during the switching process and you can't talk until the repeater drops and your cross-band repeater drops out of transmit mode. You likely won't hear the first couple of words of others and if you start talking too soon, people may not hear your first few words.
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Ah! Got you... I guess the mobile version doesn't show tags. They are typically used for keyword searches. I would never have expected that was what was referenced.
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What "above mentioned radio"? You didn't mention.
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antenna and cable questions for a home base setup
marcspaz replied to Riktar's question in Technical Discussion
Good to hear! -
antenna and cable questions for a home base setup
marcspaz replied to Riktar's question in Technical Discussion
Attenuation of LDF4-50a is about 1.4db at 467 MHz. LMR-400 is about 2.7db. -
antenna and cable questions for a home base setup
marcspaz replied to Riktar's question in Technical Discussion
Just saw the edit... do not splice lines together with barrel connectors. You are going to suffer losses as it is, with a run that long. Adding extra connections will just make it worse. As Jones mentions, LMR-400 would be good for the run, but make sure its one long run. -
antenna and cable questions for a home base setup
marcspaz replied to Riktar's question in Technical Discussion
Yes, that is correct. There is a saying in the LOS radio world that "height is might". The higher you go on each end, the better the performance and range gets. The ground absorbs UHF waves and the rest heads out to space about 15% (distance wise) past the visual horizon. So, the higher you go, the less terrain is in the way, the more land surface area is exposed because you are pushing the horizon line out further as you go up. An example would be, at 5 feet above all obstacles (about where an HT is while standing) gives you about 5 miles of radio horizon. 15 feet gives you about 9 miles to the horizon. However, 40 feet gives you 14 miles. The truth is, if nothing is in the way, and you get one station up in the air 3,000 feet (on the side of a mountain for instance) and the other radio was at sea level, you could get 125 miles with the proper power levels. With the power we are restricted to, you can get 65-70 miles with enough elevation. Sounds good! Looking forward to hearing back. -
antenna and cable questions for a home base setup
marcspaz replied to Riktar's question in Technical Discussion
With centimeter radio and cheap cable, the cable length is not going to change anything even remotely close to noticeable... likely not even measurable. Also, anything under 3:1, you won't have any risk of damage. Anything 2:1 or better is good. Anything 1.5:1 is really good. getting a 1:1 match usually means the antenna is not resonant at your target frequency. You should be very pleased with 1.4:1. Normally I target about 1.75:1 at the antenna feed point and then use an LC network to maximize output power to the antenna. Get that antenna 40+ feet in the air and you will dramatically increase your coverage and performance in the covered areas. -
I have the same problem with both my HT's, due to elevation and LOS limits. I am only 3 miles away (LOS) from a repeater and need 40/50 watts to hit it, but in another direction, I can hit a repeater 22 miles away with 5 watts, because nothing is in the way. Have you done a topo eval? Some members here have shared some online resources that are pretty cool for a quick review.
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I have a full-blown base station with a horizontal dipole and an inverted V. This demo shows my portable setup that I take to the mountains for contests, to support the county/state government, local hospitals, the Red Cross, and FEMA/DHS.
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Wow! It's a good thing you got involved! Some people just ha e no clue how radios work. I know I would not be happy to hear potential PII of mine getting sent over the air.
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It seems a little quiet, so I figured I would share a walk-thru video of a portable field setup for my radio gear. The video focuses on my Ham gear and two club events I am going to be involved in, but you can easily put something together like this for field use for any radio platform, including GMRS. In fact, the X200 antenna works great for GMRS frequencies. I've posted the SWR readings from the analyzer in another thread, a month or so back. On the low side it was 1.3:1 and the high side was 1.4:1. Not a pro video by any means, but you should get the idea. https://www.youtube.com/watch?v=n9TkDnRDn4U
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That's a really good question. But do they actually discount stuff at the show? I used to go to gun shows all the time, but found the prices were the same or higher than walking into a local brick and mortar store. So, I gave up on those types of events.
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I've spent decades in emergency services. If I worry, then you should worry. Right now, I'm more concerned about the idiots that are causing chaos and panic by over-buying food, water and TP.
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I read about that last night. The doom an gloom is getting pretty disappointing. Cancelling events 2 and 3 months out means the masses aren't too optimistic about the current health scare.
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Got you... now I'm tracking.
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Outstanding! I have a question, though. As of December 2019, there are only 195 independent nations on the planet... if we include non-sovereign nations, it only goes up to 215. Was the 300+ a typo?
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Anyone get involved in the ARRL International SSB DX contest this past weekend? How did you do? I find it amazing that people travel out of country to talk DX back to the US. I spoke to several people who live in nearby towns but were in another country for the contest. I was looking for as many countries as possible. Using 100 watts on an 80m dipole, I spoke to 110 people in 47 countries, plus Alaska and Hawaii, on 80m, 40m, 20m, and 15m! It was a good weekend. I had to stop early, though. This is the list of countries I was able to reach... Antigua & Barbuda Argentina Aruba Bahamas Barbados Belize Bermuda Bonaire Bosnia-Herzegovina Brazil Canada Canary Is. Cape Verde Cayman Is. Costa Rica Croatia Curacao Dominican Republic Ecuador England Federal Republic of Germany France French Guiana Honduras Ireland Italy Lithuania Luxembourg Martinique Montserrat New Zealand Panama Poland Portugal Puerto Rico Serbia Sint Maarten Slovenia Spain St. Kitts & Nevis St. Lucia St. Martin Sweden Turkey Turks & Caicos Is. US Virgin Is. Venezuela http://fiveguysracing.com/marc/HAM-GMRS/ARRL_2020_Int_DX_Contest.JPG
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Being convicted of a felony doesn't mean you can't get a Amateur or GMRS license. The question is asked because, following a conference with the FCC and the NCVEC, the government and community at large are looking to make the community safer. The character of the applicant is relevant, as licensees represent the US government and the citizens. Some examples that will get you denied are convictions for pedophilia, weapons or drug trafficking, human trafficking, acts of terrorism, etc. If you have a felony 'hit and run' or aggravated battery from 25 years ago, they probably wouldn't flag you. What I find amazing is, they ask on a radio license application, but someone thought it was a good idea to make it illegal to ask if you are a felon on a job application. SMH
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Simplex, duplex, noplex repeater for GMRS. Help!
marcspaz replied to yupitsnuge's question in Technical Discussion
I live in a 110 foot hole. I gave some thought to this very issue. If you're going to spend any money, just do it properly, such as using the equipment mentioned above. Otherwise you're going to spend a bunch of extra money and time trying to get the performance you want. I have a 2m repeater and a 70cm repeater at my house. I would put up a GMRS repeater if I thought my wife wouldn't toss me out...