WSAE510 Posted January 24 Report Posted January 24 Every GMRS radio groups on Facebook has a bunch of people who thinks the handheld GMRS radio is more than 5 watts. To be honest with you folks I've been told that my BTech GMRS V2 is 5 on high transmit power. I sit back and just roll my eyes in the back of my head WSAG780 and WSAZ351 1 1 Quote
WRKC935 Posted January 25 Report Posted January 25 And I can promise you that no amount of detailed explanation and math will convince them otherwise. The manufacture says it's 10 watts or whatever and they wouldn't lie. And the reason they get away with it is the same reason that lawnmower engines no longer have a horsepower rating. The lies finally caught up with them and they were required to calculate horsepower the standard way it's done and not any other way. So they took the HP ratings off the motor's and now just tell you what CC they are. That way it conveys the idea it's as powerful as a motorcycle of the same displacement. If a 400 CC motor will propel a motorcycle to 100MPH, then if you took a 400CC motor off a lawn mower and put it on a motorcycle, they infer that the motorcycle would still go 100MPH. Of course that's not the case, but it's inferred and never stated. RF power of 12 watts pertaining to a handheld is the power draw from the battery during transmit, or some other odd thing that isn't specific, but no one is requiring them to rate the radio's based on a standard watt meter into a 50 ohm dummy load. It could be their antenna has 6dB of gain no antenna, or a dummy load or some other standard that would never be accepted if came to light where the numbers came from. But a 3 watt radio with a 6db gain antenna would technically have 12 watts of ERP or effective radiated power. But again, what are they basing the power reading on. GMRS power is legally regulated at 50 watts as measured at the back of a transmitter with a standard watt meter. So there is no 'interpretation' of the rule or how the measurement is to be done. If an FCC agent comes and checks your power output, that is how it will be done. Calibrated meter with a cable jumper of a known amount of loss for the frequency being tested with. If you read in here enough, you will see people that will claim they are sending their' faulty' radio back because it doesn't do the full 50 watts it's advertised at. It's only doing 46 or 48 watts on their meter. They are not taking into account that cable loss between the meter and the radio. And yes, it's that much. tweiss3 and WSAE510 2 Quote
SvenMarbles Posted January 27 Report Posted January 27 Some models are capable of doing between 6-11 watts, never more than that though.. WSAE510 and WSAG780 2 Quote
WSAA635 Posted January 27 Report Posted January 27 From tests I've seen on the YouTubes the V2 does get somewhere between 5 and 5.5 watts which is what it's rated at. I'm sure the lesser expensive radios only get 3 to 4 watts or if they're "out of spec" maybe 8 to 10 watts but anything calibrated for GMRS use in an HT should be around 5 watts plus/minus 1 watt. JMHO, YMMV. WSAE510 1 Quote
SvenMarbles Posted January 28 Report Posted January 28 The Tidradio H8 has been demonstrated on YouTube as 10 watts on the meter… WSDD519 1 Quote
Socalgmrs Posted January 29 Report Posted January 29 I actually have a few $40 handhelds that test out to 8 and 9watts. Quote
Lscott Posted January 29 Report Posted January 29 On 1/24/2024 at 8:55 PM, WRKC935 said: If you read in here enough, you will see people that will claim they are sending their' faulty' radio back because it doesn't do the full 50 watts it's advertised at. It's only doing 46 or 48 watts on their meter. Do they send it back if it does more? SteveShannon 1 Quote
SteveShannon Posted January 29 Report Posted January 29 On 1/24/2024 at 6:55 PM, WRKC935 said: If you read in here enough, you will see people that will claim they are sending their' faulty' radio back because it doesn't do the full 50 watts it's advertised at. It's only doing 46 or 48 watts on their meter. They are not taking into account that cable loss between the meter and the radio. And yes, it's that much. On Monday, Wednesday, and Friday I try to join in on a 40 meter net. I usually run at 50 watts on digital modes but I usually turn my radio up to 99 watts output for the net. This past Friday I forgot. I checked in and the net control said I was easy to copy. Another person said I sounded a little weak compared to usual. So I checked my power and discovered that I was running at 10 watts. I had been playing with low power and had forgotten I cranked it down. Certainly, power makes a difference, but far less than people think. Nobody will ever hear the difference between 45 watts and 50 if there are no other changes. AdmiralCochrane, WRHS218, WRKC935 and 3 others 5 1 Quote
SvenMarbles Posted January 31 Report Posted January 31 Most people don’t understand how wattage plays with exponential gain antennas. People will say things like “the difference between 5 and 10 watts doesn’t matter”. That’s true if you’re using an HT in HT form. But if you’re using a 6 db gain antenna on a mobile install for example, that 5 watts is 20 watts ERP. A 10 watt radio would be 40 watts ERP (not accounting for the trivial line loss in a short mobile installation run). If you run your HT in this fashion, in a car, or even wired to an outdoor antenna at home,.. Yes, you might care about the difference between the 5 watts or 8-10 your handheld makes. It DOES matter when you get compounding ERP gains every 3 decibels on a high gain antenna.. Quote
WRXB215 Posted January 31 Report Posted January 31 @WSAK691 I agree with you. People talk about antennas and "height is might." And they are right about that. But wattage is absolutely a factor as well especially when trying to punch through the trees. People have a tendency to downplay wattage more than they should. Quote
SteveShannon Posted January 31 Report Posted January 31 11 hours ago, WSAK691 said: But if you’re using a 6 db gain antenna on a mobile install for example, that 5 watts is 20 watts ERP. A 10 watt radio would be 40 watts ERP (not accounting for the trivial line loss in a short mobile installation run). And the difference between the two radios, even through a 6 dB gain antenna, is still just one half unit on the S-meter. Absolutely, large changes in output power matter. Otherwise we could all be running 100 milliwatts. But it’s ridiculous to obsess about a radio putting out 9 watts instead of 10, or 45 watts instead of 50, even with trees. WRYZ926 and WRUU653 2 Quote
tweiss3 Posted January 31 Report Posted January 31 8 minutes ago, Sshannon said: And the difference between the two radios, even through a 6 dB gain antenna, is still just one half unit on the S-meter. Absolutely, large changes in output power matter. Otherwise we could all be running 100 milliwatts. But it’s ridiculous to obsess about a radio putting out 9 watts instead of 10, or 45 watts instead of 50, even with trees. This is exactly true. Unless your intended recipient is exactly matched to your setup, there is no need to worry over power. In fact, most repeaters are turned down for reliability, so a 100W rated repeater puts out something like 50W after the duplexer, often many are 50W rated repeaters putting out 20W after the duplexer, and have ears way beyond their transmit range. It's one reason I don't fret over having 45W UHF decks vs 50W. Now, in my communication plan, obviously, mobile radios in every car are preferred over HTs, but in that case its to get 3 miles simplex. SteveShannon, WRUU653 and WSAE510 3 Quote
Socalgmrs Posted January 31 Report Posted January 31 I find it funny….. that guys with money to burn tell new guys that have to spend $500 on a radio just to get into gmrs. then they recommend a junkie antenna. I guess I’m just blessed i live in the flat desert. My cheap 5w HTs get over 20miles simplex and my 20w base station at home gets over 200miles with a 9db gain antenna. 20w mobile in the truck is getting over 50miles simplex with a cheap mag mount. I do have some “10w” HTs that I got from out of country that test out at 8 and 9watts coupled with a 771 that sound great at 30plus miles. in my opinion it’s all about the antenna first then the radio. I refuse to spend more than about $100-$150 for a radio. I’ve got other things in life that I spend money on. Horses, quads and paying off my house as early as possible. WRUU653 and SteveShannon 1 1 Quote
WRXB215 Posted January 31 Report Posted January 31 51 minutes ago, Sshannon said: But it’s ridiculous to obsess about a radio putting out 9 watts instead of 10, or 45 watts instead of 50, even with trees. Agreed. SteveShannon and WRUU653 2 Quote
WRXB215 Posted January 31 Report Posted January 31 7 minutes ago, WRXP381 said: it’s all about the antenna first then the radio I agree with this also. WRUU653 and SteveShannon 2 Quote
SteveShannon Posted January 31 Report Posted January 31 1 hour ago, Sshannon said: And the difference between the two radios, even through a 6 dB gain antenna, is still just one half unit on the S-meter. I should have added that the real takeaway is that all of these changes contribute towards good signal strength. Doubling the power only moves the S meter by a half unit, but if you double the power and use a high gain antenna you can get one or even two S units. Using better coax can get you another half S unit or more. It’s important to be aware of all of the different places where signal strength can be lost and how they can combine against you: antenna gain, antenna placement, directionality, output power, coax loss, connector loss, even the voltage of the DC power supply. AdmiralCochrane, WRYZ926, WRUU653 and 2 others 4 1 Quote
WRYZ926 Posted February 1 Report Posted February 1 @Sshannon hit the nail square on the head. It is a combination of everything that matters. You can have a good radio and a good antenna as high as you can get it but junk coax will subtract any gains. Same as if you have a good radio and good coax but a junk antenna. SteveShannon and WRUU653 1 1 Quote
SvenMarbles Posted February 16 Report Posted February 16 I’m confused what you mean when you say the difference between the two radios is a half of an S-unit. Which two radios? One with 6db gain antenna and one with 3? Is that in a hypothetical flat plane? The difference of ERP gain increasing by an entire order of magnitude is the difference of being heard or not in various terrain circumstances. I use a 10 watt radio at home. Through 50 feet of LMR-400. About 7.2 watts reaches the antenna for an ERP of 57.6 watts. When I plug in my 4 watt Baofeng with the same formula, the ERP is about 23 watts and I’m not heard in areas that I was scratching into before. Or, I’m scratching in where I was loud before. It matters.. Quote
SteveShannon Posted February 16 Report Posted February 16 On 1/31/2024 at 9:38 AM, Sshannon said: Doubling the power only moves the S meter by a half unit, but if you double the power and use a high gain antenna you can get one or even two S units. 2 hours ago, WSAK691 said: I’m confused what you mean when you say the difference between the two radios is a half of an S-unit. I’m sorry you’re confused. I don’t think my statement (quoted above) is confusing, but maybe I made it too terse. Doubling power, with no other changes, results in a difference of 1/2 S unit. That’s by definition - one S-unit represents a difference of 6 dB, which is 4 times the power. That’s substantial but when you’re sitting in front of a radio it’s sometimes difficult to quantify. Making other changes (such as antennas) are more likely to result in changes as measured by the S-meter. Quote
SvenMarbles Posted February 16 Report Posted February 16 6 hours ago, Sshannon said: I’m sorry you’re confused. I don’t think my statement (quoted above) is confusing, but maybe I made it too terse. Doubling power, with no other changes, results in a difference of 1/2 S unit. That’s by definition - one S-unit represents a difference of 6 dB, which is 4 times the power. That’s substantial but when you’re sitting in front of a radio it’s sometimes difficult to quantify. Making other changes (such as antennas) are more likely to result in changes as measured by the S-meter. Got it. I guess it wasn’t registering with me the whole S-meter part. So what you’re saying is that 1 S-unit increment is very significant. Quote
SteveShannon Posted February 16 Report Posted February 16 1 hour ago, WSAK691 said: Got it. I guess it wasn’t registering with me the whole S-meter part. So what you’re saying is that 1 S-unit increment is very significant. Referring back to what you said earlier: On 1/30/2024 at 8:30 PM, WSAK691 said: But if you’re using a 6 db gain antenna on a mobile install for example, that 5 watts is 20 watts ERP. A 10 watt radio would be 40 watts ERP (not accounting for the trivial line loss in a short mobile installation run). You talked about how a 5 watt radio with a 6 dB gain antenna puts out 20 watts ERP and a 10 watt radio with that same 6 dB antenna puts out 40 watts ERP. You talked about how that gain compounded. You’re exactly right, but just as the difference between a 5 watt radio and a 10 watt radio is only 1/2 S-unit, the difference between 20 watts ERP and 40 watts ERP is still only a half S-meter unit. But adding the antenna made a full S-unit difference for both radios, if you’re in the direction of the 6dB gain. That’s an audible difference. Half of an S-unit may or may not be subjectively distinguishable to a human ear. One S-unit is audibly different, even though it’s four times the power. But I wouldn’t consider it very significant. Two S-units would be very significant, in my personal scale of significance. S-units provide us something that is objectively quantifiable, but whether something is significant or very significant is subjective. You may feel that one S-unit is very significant. Quote
SvenMarbles Posted February 16 Report Posted February 16 9 minutes ago, Sshannon said: Referring back to what you said earlier: You talked about how a 5 watt radio with a 6 dB gain antenna puts out 20 watts ERP and a 10 watt radio with that same 6 dB antenna puts out 40 watts ERP. You’re exactly right, but just as the difference between a 5 watt radio and a 10 watt radio is only 1/2 S-unit, the difference between 20 watts ERP and 40 watts ERP is still just a half S-meter unit. But adding the antenna made a full S-unit difference for both radios,if you’re in the direction of the 6dB gain. Half of an S-unit may or may not be subjectively distinguishable to a human ear. One S-unit is an audible difference, even though it’s four times the power. It’s not distinguishable to the human ear as long as you’re assuming that both radios were already positioned in terrain to copy eachother fine. That’s not the exercise. In actual use cases of running mobile radio, you go up grades, down grades, back behind things, and all variety of constantly changing attenuating variables. The difference of being scratchy but readable in stretches, and not being heard. That’s the difference of a complete order of magnitude increase in ERP. Your conceptualization of point A to Point B radio coms sort of paints the mental image of 2 guys at a desk radio 4 miles apart. And assuming that, you’re not wrong. But there are all variety of use cases. Some like GMRS as a ham radio hobby facsimile, and some like it for actual in-field coms. Quote
SteveShannon Posted February 16 Report Posted February 16 8 minutes ago, WSAK691 said: It’s not distinguishable to the human ear as long as you’re assuming that both radios were already positioned in terrain to copy eachother fine. That’s not the exercise. In actual use cases of running mobile radio, you go up grades, down grades, back behind things, and all variety of constantly changing attenuating variables. The difference of being scratchy but readable in stretches, and not being heard. That’s the difference of a complete order of magnitude increase in ERP. Your conceptualization of point A to Point B radio coms sort of paints the mental image of 2 guys at a desk radio 4 miles apart. And assuming that, you’re not wrong. But there are all variety of use cases. Some like GMRS as a ham radio hobby facsimile, and some like it for actual in-field coms. Now you’re off on a bit of a tangent, but I agree that a 10 dB increase is very significant. Quote
Radioguy7268 Posted February 16 Report Posted February 16 I'm sorry, but if you're using a Baofeng (or other CCR with a Direct Conversion receiver on a Chip) then you're missing half the show if you're just focused on transmit power & ERP. The real game is played on receiver selectivity & desense. Sure, the CCR's have some good/great specs (on paper) for sensitivity in a laboratory testing environment. They fall short when you start looking at adjacent channel rejection and desense. Stuff like that matters in the real world. Measure your Signal to Noise and Distortion and now you've got something worth measuring on the receive side. Do you have tools that can generate a low level calibrated output to test receiver performance? 10 watts in a handheld looks great on paper, but it doesn't take into account how well the other party receives. I'd rather have lower ERP with a more selective receiver that can actually pick out a desired signal at -120 dBm & recover it into understandable audio. If your CCR is still sitting silent in the presence of a -114 dBm signal, you're missing out on more than 6 dB in the math of Signal to Noise. The ERP side says you'd need to quadruple your transmit power to achieve the same S/N ratio. Take a look at the Motorola XPR "e" series and the Vertex EVX radios if you want to see what a SDR chip coupled with good electronics and a little filtering can look like. Heck, even the older CDM mobiles had great analog receivers with some nice audio. Focusing on transmit power alone is missing half the equation. tweiss3, gortex2 and PACNWComms 3 Quote
quarterwave Posted February 16 Report Posted February 16 Going back to one of my old experiences when I worked for Motorola years ago... A small city police department had a failure of their old GE repeater they had been nursing along for many years, so they needed a new one. Budgets were tight, but they insisted on a 100 watt unit. Now, the repeater was naturally on a hill, on a water tank, and was at the highest point in the city, and no more than a mile from the city limits in any direction. They wanted 100 watts. VHF, carrier squelch mind you...and 100 watts. While they waited for a new repeater, we loaned them a Desktrac (not what you need for public safety, but it'll work in a pinch). Once on the air, the asst chief said, man, that sounds good. And the range is great, can we just keep that one? Is it 100 watts? Sure, it's 100 watts. It was in fact 25 watts..... no one could tell. They later got a new repeater, but we still didn't set it up for 100 watts. Point is, don't get hung up on wattage, use what works for the situation you need it in. SteveShannon, WSAE510, Radioguy7268 and 3 others 4 2 Quote
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