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gortex2 reacted to Lscott in To be or not to be...swr inline
All of the radios I have I try to get the service manuals for them along with the operators manuals. Being an engineer I look through the schematics at times to see what makes a specific radio "tick" so to speak.
What I've found is just about, if not all, the commercial LMR radios I have use some kind of turntable front end filtering. Those filters are typically before the first IF stage and acts as a pre-filter to improve the image response and the possible desense of the IF amplifier chain after the filters.
One of two techniques I've seen used are varactor diodes or variable inductance chokes. Both are "biased" by an output from the micro running the radio. As the frequency is changed the front end filter is electrically tuned to match the programed RX frequency.
The reason why CCR's are so cheap as you pointed out the front end filtering is minimal. This isn't just a problem with CCR's however. Many Ham HT's, from name brand manufactures, suffer from the same problem. As Hams we like the idea of a wide RX range for scanning etc. however that comes at a price, a wide open front end. To add in the fancy tuneable front end filters adds cost and complexity to the radio.
To show you what is in some of the CCR's I found a schematic, reportedly, for the commonly mentioned UV-5R. I'm going to guess that derivatives of this radio the schematic won't look too much different. After all what did you expect to see in a radio that sells for about the same price as a kid's FRS bubble pack toy radio?
Oh, the harmonics on TX suck too. If you'll notice some of the harmonic tests were done at a load impedance of 25 ohms, not the expected nominal 50 ohms. At 25 ohms that would correspond to an SWR of 2:1 so the party doing the testing wanted to see if the harmonic content was SWR dependent.
SCHEMATIC Baofeng UV-5R.pdf UV-5R VHF Harmonics Test.pdf
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gortex2 reacted to PACNWComms in Base station grounding
I started reading this thread and went right to Motorola R56, then saw you had posted a link already. Attaching it in case that is unreachable. Chapter's 4 and 5 go into a great deal of detail on what needs to be done. Thank you for posting this. Many could take head in this before having their home catch fire or lose equipment/property/and life to a lightening strike.
In previous work in the oil industry, ship antennas would often get hit by lightening strikes. Polyphaser's and actually grounding them in the most direct route saved all but one radio over the course of ten years. With the price of copper, it is understandable why people skimp on this part, but it could save life and property. It is an area that even the professionals try to save money. A couple of years ago, I had to have a 9-1-1 Public Safety Answering Point under construction, re-pour the concrete base of their antenna tower, as they did not place grounding mesh underneath. The building also needed some walls torn apart to retrofit grounding for the many radio racks, antenna coax penetrations, and backroom equipment. Grounding also improves signal to noise by having gear at the same effective ground, to include the call taking (telephone) systems in use at the sites. Follow R56 and do at least the minimum, adding lightening protection, copper rods and bonding pieces to each antenna/radio system.
Motorola-Standards-and-Guidelines-for-Communication-Sites-R56-Manual.pdf
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gortex2 got a reaction from PACNWComms in Base station grounding
To do grounding the proper way will cost more than your radio and antenna combined. I would at minimum put a polyphaser/transector where the feedline enters your house. Grounded to a ground rod or building electrical if possible. Minimum should be #6. Below you can grab a polyphaser for around $75.00.
If you have a mast that is metal you should try to ground that to the same point as the polyphaser.
https://www.dxengineering.com/search/brand/polyphaser?cm_mmc=ppc-google-_-search-_-vendors-_-keyword&gclid=Cj0KCQiAoY-PBhCNARIsABcz772B_ofhyz47cdi2i0FWZStI2MENLroGG3T5-nRA_loZkBmDokje9fsaAhwlEALw_wcB
Good manuals to look at.
https://wiki.w9cr.net/index.php/R56_-_Standards_and_Guidelines_for_Communication_Sites
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gortex2 got a reaction from PACNWComms in What repeater is this?
Also remember repeaters don't need to be listed anyplace. None of my repeaters are listed at this time as I got tired of dealing with unwanted folks on them. There are repeaters out there that have coverage and are linked that may not be open to other users. Remember not all repeaters are open as in ham radio.
Here is a link of a GMRS network that may have something in your area - https://midwestgmrs.com/
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gortex2 reacted to wrop206 in What I heard on a three day road trip... (not much)
I rarely hear traffic on the road anymore. Most people use their smart phone on waze for routing and road conditions. GMRS has been a savior here in Arizona for overlanding offroad because you lose a cell phone signal as soon as you leave the pavement.
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gortex2 got a reaction from Lscott in Which digital voice mode do you prefer?
I wouldn't say a fiber link is better than DSL. My house actually had DSL for 3 years as we had no fiber or highspeed from any other place. I averaged 2-3mb and that's it for up and down. My P25 would work most of the time until we got down below a 1mb then I would get garbled on the base. For link speeds it really depends on the system and how much it needs. A site with 3 channels of TRBO and controller needs more than a single channel. QOS is also very important. In a closed network such as public safety uses its easy to have QoS for Voice and less Qos for other traffic. In the commercial world the ISP doesn't give you or I QoS for our home networking. We just share the pipe and when it gets busy it slows down. Depending on the importance of the system will change the requirement from the ISP. Thats why when you call someone like Verizon for Fiber they have different plans for residential or business. Normally you will find a business account cost more for the same speeds. When building a system going to the ISP with a SLA (System Link Agreement) we will provide what we need.
And for reference a system I worked on a system 15 years ago was a trunked system with 8 channels. We used a single T1 to the site. It was on a microwave link so congestion was not an issue.
One of the things I think hams forget about in regards to the LTE style links is the idea of a disaster. The LTE modem on the Trbo repeater is going to work about the same as your cell phone. For those that have been involved in disaster scenarios you know that cell can be overloaded or completely gone. Many times Fiber and copper phone lines still work. All in all its about what service you need and want to provide. If I'm going t promote my P25 ham gear as a RACES/ARES type system I am going to make sure it has the ability to help, otherwise its just another radio on the air.
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gortex2 reacted to n4gix in Friendly reminder to those who use eBay, PayPal, Venmo... etc...
At what age is Social Security not taxable? At 65 to 67, depending on the year of your birth, you are at full retirement age and can get full Social Security retirement benefits tax-free. That is directly from the IRS FAQ. I'm 73 now, so... ? -
gortex2 reacted to gman1971 in New model Baofeng appears to be a great improvement
Uuuh... getting snarky now... let me repeat this for you: You REALLY are a legend on your own mind if you think that you can tell me what I need. After the last several post of yours I wouldn't touch anything coming from you with a ten foot pole... and I am sorry to disappoint you, but I don't need any sleep ATM, I can do this all night long. Lets go, lets see if we can get the thread locked... by posting more of that nonsense of yours; hmm, lets see if you can find someone's quote and twist it real good, lets see if that much twisting is enough to prove that the USA never landed on the Moon, or better yet... the Earth is flat!! yeah, did you know the Earth could actually be flat? Because I've read in a bunch of articles, all written by very reputable sources, you know, experts in the matter, they claim the Earth could indeed be flat.
G.
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gortex2 reacted to gman1971 in New model Baofeng appears to be a great improvement
@Lscott This is kind of strategy this individual uses, baits people into agreeing, and then he uses it against you when its convenient.
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gortex2 reacted to Lscott in New model Baofeng appears to be a great improvement
These GMRS forums is NOT the place to discuss your politics. If you want to do that take it elsewhere.
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gortex2 reacted to WRPB409 in Does Line A still exist?
My GMRS License was granted on 1-14-22 and there is a reference to not operating North of Line A and East of line C on 462.650 MHZ, 462.700 and 467.700 unless a previous authorized such operation.
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gortex2 reacted to PACNWComms in Does Line A still exist?
My license was granted 11-02-2021, and lists the three you have above, and also 467.650 MHz.
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gortex2 reacted to WyoJoe in Recommended Contact Procedure
It appears that these prohibitions would apply to Part 90 equipment. I haven't investigated this matter, but is there a similar prohibition for Part 97 (amateur radio service) equipment?
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gortex2 reacted to SteveShannon in Recommended Contact Procedure
The part 90 rules don't just apply to equipment certified under part 90, but also regulate the use of any equipment in "the Public Safety, Industrial/Business Radio Pool, and Radiolocation Radio Services."
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gortex2 reacted to gman1971 in New model Baofeng appears to be a great improvement
My opinion about radios is pretty crystal clear, is it not? and which happens to be exactly what this forum is all about, radios and GMRS.
Now, your style of discourse seems (to me) like you just like throwing some "hints" that appear (to me) to be either really bad jokes, or bait, perhaps hoping that someone like me bites so you can then twist their argument(s) against them, something you seem quite good at that...
To me, there was no reason to state that my CCR collection picture was related to the spread of anything, even if it is a joke, its a pretty poor joke, let me tell you. Otherwise its just bait, and choosing a political subject that I know its a very polarizing subject because of what I see at dealing with personnel at work in the real world; also happens to be unrelated to the thread as well. Then posted an unrelated J6 picture on a Baofeng thread, that casually shows a Baofeng... Again, either your taste for jokes is pretty poor, or you are just trying to bait, because just like the spread matter, the J6 subject is also a very polarizing issue as well, and totally uncalled for on a "reduced spurious emissions Baofeng thread". Then, on the Paypal thread that I started just to state a fact, you came and started posting things like "one side jacking up taxes..." again its your opinion on another polarizing subject, which again, for the purpose of the thread, who cares... well I guess you do, but I don't care, and I am sure as heck that a lot of people in the forum don't care either.
You see, that seems to be the problem. I am not looking for your approval, nor your agreement in here, Michael, what you and I believe is not something that your rebuttal, or perhaps your agreement is going to change our opinions on the subject. Proof of what I speak is that even me showing the data that proves CCRs are trash, yet you still buy them... there is nothing I can do, except keep repeating that they are trash.
The subject of CCRs, on the other hand, first off, its related to the forum: its a radio subject, and then, its pretty easy to prove they are junk, and that is my position on the matter. We can discuss radios all day long, but in the end I have 2+ years worth of collected data around multiple sites, using RF RSSI meter, spectrum analyzers and ISOTee test that allows me to be combative and blunt as a brick to call random "opinions, feelings or voodoo magic" total and utter BS. I am sorry if I don't share your warm and fuzzy feelings when holding a GD77 in my hands, but I can't interpret the data in any other way. I also stand behind what I am so vehement about, as I've helped several members in this forum board get started on their Motorola journey, much the same way that some kind souls at Communication Support helped me get started on Motorola equipment when I was a total noob lost in the CCR junk field.
The hope is that if I can convince just one more person to steer clear of the CCR junk field... then mission accomplished.
G.
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gortex2 reacted to gman1971 in New model Baofeng appears to be a great improvement
@Lscott
And you are right, I certainly don't know how informed or uninformed those people are/were, but do you?
The fact is that some people make fun of people using CCRs (regardless of where, and how they are/were used) but they are using CCRs themselves too... that is the hilarious part.
@MichaelLAX
And how do you know those facts? I support that CCRs are garbage with data from ISO-tee tests I've performed, and that is where it ends. You were the first person to post J6 pictures on this thread, did you not? And now you are claiming that those people knew well what they were doing,
election?, virus?, an eye patch? what are you talking about. Once again: don't put words in my mouth, because you seem to do that quite often...
Tragic is the fact that this being a radio forum and here we are talking about matters that are not related to radios pretending to use radios as an excuse.
So, if you want to be cheap and use garbage radios, then go for it.
Then lets leave politics to politicians... and I am NOT a politician. Now, if you don't like what you see in politics, then its very simple: you vote for what you'd like to see then; then after the results are in, accept that if you lose, it is the way it has to be, and that if you win, be mindful that others might not be as happy as you are. That's it!! Now, If just voting alone is not enough for you, then get involved in politics, start your own political career, etc. Otherwise, conspiracy theories, whining, moaning and whatever other nonsense you spew in a radio forum are not going to help solve anything.
G.
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gortex2 got a reaction from wayoverthere in Which digital voice mode do you prefer?
I wouldn't say a fiber link is better than DSL. My house actually had DSL for 3 years as we had no fiber or highspeed from any other place. I averaged 2-3mb and that's it for up and down. My P25 would work most of the time until we got down below a 1mb then I would get garbled on the base. For link speeds it really depends on the system and how much it needs. A site with 3 channels of TRBO and controller needs more than a single channel. QOS is also very important. In a closed network such as public safety uses its easy to have QoS for Voice and less Qos for other traffic. In the commercial world the ISP doesn't give you or I QoS for our home networking. We just share the pipe and when it gets busy it slows down. Depending on the importance of the system will change the requirement from the ISP. Thats why when you call someone like Verizon for Fiber they have different plans for residential or business. Normally you will find a business account cost more for the same speeds. When building a system going to the ISP with a SLA (System Link Agreement) we will provide what we need.
And for reference a system I worked on a system 15 years ago was a trunked system with 8 channels. We used a single T1 to the site. It was on a microwave link so congestion was not an issue.
One of the things I think hams forget about in regards to the LTE style links is the idea of a disaster. The LTE modem on the Trbo repeater is going to work about the same as your cell phone. For those that have been involved in disaster scenarios you know that cell can be overloaded or completely gone. Many times Fiber and copper phone lines still work. All in all its about what service you need and want to provide. If I'm going t promote my P25 ham gear as a RACES/ARES type system I am going to make sure it has the ability to help, otherwise its just another radio on the air.
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gortex2 got a reaction from gman1971 in Which digital voice mode do you prefer?
I wouldn't say a fiber link is better than DSL. My house actually had DSL for 3 years as we had no fiber or highspeed from any other place. I averaged 2-3mb and that's it for up and down. My P25 would work most of the time until we got down below a 1mb then I would get garbled on the base. For link speeds it really depends on the system and how much it needs. A site with 3 channels of TRBO and controller needs more than a single channel. QOS is also very important. In a closed network such as public safety uses its easy to have QoS for Voice and less Qos for other traffic. In the commercial world the ISP doesn't give you or I QoS for our home networking. We just share the pipe and when it gets busy it slows down. Depending on the importance of the system will change the requirement from the ISP. Thats why when you call someone like Verizon for Fiber they have different plans for residential or business. Normally you will find a business account cost more for the same speeds. When building a system going to the ISP with a SLA (System Link Agreement) we will provide what we need.
And for reference a system I worked on a system 15 years ago was a trunked system with 8 channels. We used a single T1 to the site. It was on a microwave link so congestion was not an issue.
One of the things I think hams forget about in regards to the LTE style links is the idea of a disaster. The LTE modem on the Trbo repeater is going to work about the same as your cell phone. For those that have been involved in disaster scenarios you know that cell can be overloaded or completely gone. Many times Fiber and copper phone lines still work. All in all its about what service you need and want to provide. If I'm going t promote my P25 ham gear as a RACES/ARES type system I am going to make sure it has the ability to help, otherwise its just another radio on the air.
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gortex2 got a reaction from n4gix in noob question
I think NYC area has a similar dispute that has been going on for years. After reading about the CA stuff I'm glad I live in the country ! I could put all 8 repeaters up but I'd have to give each cow their own channel
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gortex2 reacted to Lscott in Recommended Contact Procedure
Just for the record this is the FCC rule part covering public safety frequencies.
https://www.law.cornell.edu/cfr/text/47/90.20
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gortex2 got a reaction from gman1971 in Which digital voice mode do you prefer?
@Lscott Yes it would, but most commercial installations have no issues with getting proper links. I know some locations can be challenging to get a Fiber or Highspeed connection but I have seen Microwave links to another location to grab an ISP from. Alot of the commercial LMR stuff I have seen and worked on was done this way if there was not fiber to the site. More and more public safety is getting Fiber to sites as a redundant link and with coordination can be very beneficial to other users on that site.
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gortex2 reacted to Lscott in Which digital voice mode do you prefer?
The few I got were between $50 and $100 each.
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gortex2 reacted to gman1971 in Which digital voice mode do you prefer?
I don't know if its just a matter of being cheap anymore, ... b/c a lot of the used LMR quality gear can be found for less money online than new CCR garbage...
Back when I started on Motorola radios you could find used XPR6550 in great condition for <60 bucks... so...
G.
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gortex2 got a reaction from gman1971 in Which digital voice mode do you prefer?
That was my point. Most hams are dirt cheap. They wont spend $100 a month on a good ethernet link for a tower site. Quality costs money.
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gortex2 got a reaction from DeoVindice in Which digital voice mode do you prefer?
@wayoverthere DMR sounds good when setup correctly and uses good radios. When DMR first got popular the only option was Motorola MotoTrbo repeaters and radios. None of the CCR market was building anything. Over time they did. I know of a few DMR repeaters that sound pretty good over the air. They are mostly MotoTrbo but some other LMR brands on the air also. On the other side there are a lot of "home brew" repeaters now on the air with MMDVM boards on analog radios. Most that get put up never get aligned or setup properly and don't have the audio quality of a LMR repeater. Mostly because many hams don't have the test gear required or the know how to set them up right.
Next issue is the subscribers. Again the CCR market has flourished and blanketed the market with cheap stuff. They don't sound as good and putting them over a home brew repeater makes it sound even worse. Some of us have learned the hard way after buying "economy" radios then spending a bit more on a true LMR radio the difference. Even though I have many high quality P25 radios I got suckered into the cheap DMR market when I wanted to dabble in DMR. Mostly because it was easy. The radio got used once. Its in a box. Sadly DMR is dead where I am so only listened when working in different cities. I did finally get an XPR7550 and its night and day from the MD I had. YMMV