mbrun Posted February 15, 2021 Report Posted February 15, 2021 This is the follow-up report based on findings in my environment from a set of side-by-side comparisons. If you are looking for a short read, I suggest you move on now and not look back or forever hold your piece. . You have been warned. Before I begin, I want to give special thanks and credit to RadioGuy7268 for his graciousness and the trust he placed in me with his equipment for this effort. It would not have been possible without you. Thank You! What was the comparison all about and why did I undertake it? Manufacturer specifications really are an important thing to review when purchasing a radio. Most humans don’t ‘think’ numbers however. Instead we think about and relate to real world outcomes. What we want to know is if a product will or will not meet our expectations and ‘what can I reasonably expect.’ Sadly the manufacturer’s marketing information, by design, can lead folks into a fantasy world that may have one believing we can have the sky and life will be rosy if we only purchased and used their product. Everyone reading this can relate to the absurd advertising claim on the Midland (and other’s) radio package of a 36 mile range for their top-end GMRS hand-held radio. They do this conscientiously knowing no soul on earth will ever achieve this range in practical use. Sadly though, fantasy sells, even in radio. The more technical the person, the more numbers have meaning. They gain more meaning when they can be related to real life. For example: To the uninitiated, if I ask them how loud something might sound if I doubled the sound power of something they were listening too they might say it would sound twice as load. But that would not be the case. In real life testing researchers found that if the power was doubled (3dB louder) it would be just barely noticeable to the average human. In reality, the power would actually need to increased by 10dB (10-times the power) before the person (on average) would subjectively conclude the level had actually doubled. It is through this type of learning that gives meaning to the various numbers that appear in technical specifications a manufacture may publish. Then we have experiences and opinions. Both are yours, neither of them may be the same as mine. If I shared with you (and I have) that I have communicated successfully well via a GMRS repeater 50 miles away, you might start to believe that if you switched to the use to the same equipment as I then you would be able to do the same. Maybe, maybe not. In the same way, when I read the experiences (or opinions) of others I may start to thinking I too could experience much better results if I switched to the equipment they use. Maybe, maybe not. My conditions are different than yours. When I purchased my current and now primary GMRS handheld I had high hopes for its performance. I bought it because I wanted simplex capability substantially better than I had. I also wanted repeater support, and ability to use it with an external antenna. Imagine my surprise when I experienced only marginally (barely noticeable) better simplex distance over the model it replaced. What a disappointment! I spent 2-3/4 times the price and ended with a radio that, in my environment, achieved maybe 5%-10% increase in range (HT-HT). While disappointed, I am pleased with my purchase and have publicly admitted I would buy the radio again. The features and qualities of the radio that are currently meaningful to me more than justify the additional price. But I really did want much better simplex distance. Like many of you I have read the posts of others sharing their opinions and experiences with regards to the use of ‘commercial’ part 90 radios. Many great experiences (or opinions) have been shared, and some very bold statements have been made (e.g. ‘10x the range’). Such comments caused me naturally to think that perhaps I too should consider such options. Maybe then I could achieve my simplex goals. The commercial prophets had sowed their seeds and thus I have been seriously considering obtaining higher priced commercial-grade stuff. However, my knowledge and life experiences have provided me enough wisdom and little angel on the other shoulder whispering in my ear saying “trust but verify”. Would this equipment really make a difference ‘in my environment?’. I have never owned nor operated ‘commercial grade’ radio equipment for any extensive use. Instead I have always owned consumer grade and ‘amateur’ stuff. As a consequence of my experience I could not say first hand if commercial performs obviously better in practice like others have said it does. I do admit that I almost blindly accept that commercial equipment will likely be built to last longer, stand up to more rigorous use, perhaps even in harsh environments, but before I am willing to make a greater investment for personal-use, I really want to know that the equipment will result in noticeably better outcomes material to me. It is hard to image a scenario again where I find myself investing 2-10 times as much and getting nothing more of what I really want in return. So that leads us to here. I reached out to this community for some assistance, and assistance is what I graciously received. I sought the opportunity to do some side by side field comparisons between my current GMRS HTs (KG-805G) and some ‘commercial’ grade HTs. I had hoped for perhaps one or two premium models. I ended up being blessed with 5. All Motorolas. I told myself that if I could double or nearly double the range in my environment I would plan to switch. So in full disclosure, I tell that when I went into my comparisons cautiously optimistic that I would achieve confirmation of the following: 1. Commercial Part-90 Radios will exhibit notably greater range, in my environment, than any equipment I own.2. Commercial Part-90 Radios will exhibit the continued ability to receive and produce intelligible audio at notably increased distances than any equipment I own when receiving in the presence of adjacent channel interference. Now, let me set the stage for comparisons. I live in a semi rural area about 20 miles southeast of Cincinnati. My elevation above sea level is just about 875’ which I believe to be in higher-most percentile of the region, and on par with the ground elevation of one of the highest profile repeaters in the area. The terrain around me is mostly flat to slightly rolling. I estimate that within a few miles of my home the land is 60% or more trees with the rest a mixture of residential, open fields and light single story commercial. When I walk down my street using my existing GMRS HTs I experience simplex coverage that goes from perfect (full quieting) at the home and out to a distance of 4/10 miles. Thereafter, noise emerges but communications remains 100% reliable out to about 6/10ths mile. Beyond 6/10ths mile and out to 1.4 miles, communication is unreliable at best. Within this unreliable zone communication quality ranges from noisy but intelligble to very noisy and partially copiable, to non-existent. All this within 1.4 miles distance by way the crow flies. Range or “Sensitivity” Testing Because my street allows me to experience everything from great to nothing, it offers a great initial test bed. I theory that any radio with notably better receive capability will pop its head above the rest while operated in the unreliable (fringe) area between 6/10 and 1.4 miles. My plan was that when I identify radio(s) that stand out I will perform more extensive distance testing at greater distances and in different directions. For my range tests, all operations were HT to HT, theoretically enabling the ability to spot notable sensitivity differences in a short physical distance. My wife operated an HT on the coach near the front window of our home while I went pedestrian. Where model-matched pairs of radios were available, my wife and I each operated two models, a KG-805G and another identical model. Where we did not have identical models for both ends, my wife used a single radio at the house (KG-805G) for consistency, while I carried a KG-805G plus another model. For each comparison, I would walk on the street while walking and talking with her on the radios. I would stop about every 200-300 feet. We would communicate using identical models, then perform cross-model communications. If we could communicate, we noted that location and moved on. When we entered the unreliable (fringe) area we continued with the pattern. When neither receiver would receive a signal at the location we moved on. When we encountered a location where one radio opened up and the other did not, we spent a little more time. Heavy noise on one or both models was an indication we were at the fringe for that radio. When presented with this his condition I would alternate between both models on my end while my wife consistently used the same radio on her end. I would hold each radio in the air in the same way (overhead and in front of me, with my body out of the receive path). I would move each radio around slightly looking to see if minor repositioning made a difference in the ability to receive and in quality of audio. If we found a model that worked in a fringe area where another would not, even after minor repositioning, we would know that we had found a candidate that exhibited more effective sensitivity and that would probably work better in many other environments as well. See the summary below. Adjacent Channel Interference Testing. The next set of tests were practical adjacent-channel selectivity tests. The intent of these tests was to ascertain which radios where obviously less subject to desense in the presence of adjacent channel interference, based on the use of a common desense source. The hope was to identify, in relative terms, how much further a given receiver could receive satisfactorily when subjected to a consistent level of adjacent channel interference. For this test, one additional radio was added to the mix, a Midland GXT1000. For these tests, my wife operated a single model radio in the house for the duration of the tests. For this test her radio was hooked up to a Ed-Fong roll-up J-pole antenna hanging inside at the front picture window. I went pedestrian. I took 7 models of radios with me to evaluate each back to back at each location I stopped. My wife read from the US Constitution while I confirmed I had reception on each model. Once good reception was confirmed I would hold each radio overhead at about 45 degree elevation in front of me, while below and behind me I held and keyed up a 1/2 watt ERP radio. I always made sure that my body was between the two radios I held and that my body was out of the RF path from my wife to the device under test. Separation between the radios I held is estimated at 6 feet (two arm lengths). Tests were performed at various distances along the same 1.4 mile stretch of my street. Findings from my Comparisons I found only minor (but not notable) differences between (4) of the Motorola’s and the KG-805G on the day of the tests. (2) Models, the EVX-S24 and VX-261, both seemed to exhibit the same sensitivity compared to the KG-805G, but struggled to open squelch just a hair more when in the fringe area. Both of these radios also seemed to exhibited a bit more audible noise when squelch did open up. (2) Models, the XPR-6550 and XPR-7550, both exhibited just the opposite. These two models seemed to open squelch just a bit sooner than the KG-805G, but on par nearly the same. (1) Motorola, the EVX-534 exhibited only about 1/2 mile of usable distance (A1 on Map) which suggests it was not functioning properly or perhaps its squelch setting was too high. Although two models appeared to open squelch a hair better and two a hair less, there was never a case (except for the EVX-534) where one radio opened squelch and the others did not when held in the same or nearly identical location (+/- 6 inches). My results suggests there is insignificant difference in the effective sensitivity between the KG-805G and the (4) Motorolas, as none of them reproduced audio at a spot in the fringe area where the KG-805G did not receive and reproduce audio. Since no radio demonstrated better sensitivity in the fringe area I concluded that no further range comparisons were warranted. So this concluded my sensitivity comparisons. Findings from my Adjacent Channel Interference Comparisons Findings here are significant in that it was observed that in the presence of my adjacent channel interference signal, not a single radio (KG-805G or other) opened squelch nor would reproduce audio under test conditions beyond a distance of about 3/10 mile (B1 on map). At 3/10 of a mile and less, all models tested, except the GTX1000, opened squelch. Even as close as 1/10 mile (B2 on map) the GTX1000 would not open up squelch, showing a significantly reduced usable distance compared to the other models. It was noted that when the radios opened squelch that the quality of audio through all the radios was significantly degraded. Even with the audio degraded, with carefully listening, the words could be understood from all radios that did open squelch. As the radios moved closer and closer to the home, the degree of audio degradation decreased. Subjectively speaking, I ranked the radios in the following order in terms of intelligibility when subjected to the interference condition at the 3/10 mile. XPR7550, XPR6550, KG-805G, VX-261, EVX-S24, EVX-534.Then again at 1/10 mile I ranked that as follows: XPR7550, XPR6550, KG-805G, EVX-534, EVX-S24, VX-261 at 1/10 mile. Conclusions Staying within the bounds of what I set out to do, here are my conclusions. In my physical and RF environment, given the objective of maximum simplex range (HT-HT) there is was no material benefit to switching to commercial grade part 90 radios from my current KG-805G radio. No part 90 radio model demonstrated any materially better sensitivity nor increased range under static RF conditions; no radio demonstrated a materially increased range under adjacent interference conditions. All were equally as effective and I found zero increased range benefit to justify a model change. Saying it another way. In my environment, with locally strongly attenuated signals, the difference between the KG-805G and the part 90 radios was not significant. The GTX1000 radio, Midland’s long-time flagship bubble-wrap radio, while reasonably sensitive, is an inferior performer in the presence of adjacent channel interference, giving credibility to the many assertions that radio-on-a chip radios can/will have limited usability in high RF environments. Opinion The cost difference between the KG-805G and Midland GTX-1000 can be justified considering the KG-805G outperformed it by a factor of 3 when exposed to adjacent channel interference as was the case in my comparisons. Users of the GTX1000 (or any like performer) at high-occupancy public events may find their usable range substantially and undesirably reduced compared to users of better models when there are a lot of GMRS and FRS radios in active use in the vicinity. The cost difference between a KG-805G and a new Motorola radio is not justifiable when the key objective is maximum range (HT-HT), while it may be justified when other qualities are deemed more important. For those interested, here is a google earth image with annotations of where the tests were conducted. I personally found this effort very beneficial. Nothing like getting your feet wet and experiencing something first hand. If you made it this far, thanks for sticking with me. And once again, Thanks to RadioGuy7268. Best regards to you all. MichaelWRHS965KE8PLM Edited for spelling.Edited to amend conclusion. Lwood, Radioguy7268, wayoverthere and 5 others 8 Quote
axorlov Posted February 15, 2021 Report Posted February 15, 2021 Thanks! Very good hands-on. But was it narrow-band or wide-band with the 805G and Motorolas? I'm guessing narrow-band, since you have GXT1000 in the mix. Also, with the GXT1000, did you use the 5W channels or the 0.5W? I'm guessing again the full-power, judging by the results. Quote
wayoverthere Posted February 15, 2021 Report Posted February 15, 2021 It's kind of interesting seeing how well the wouxun did, at least in the environment you're working with. Thank you for all the effort you put into this...interesting reading. Quote
berkinet Posted February 15, 2021 Report Posted February 15, 2021 .... Because my street allows me to experience everything from great to nothing, it offers a great initial test bed. I theory that any radio with notably better receive capability will pop its head above the rest while operated in the unreliable (fringe) area between 6/10 and 1.4 miles. My plan was that when I identify radio(s) that stand out I will perform more extensive distance testing at greater distances and in different directions. .... Thank you for doing these tests and putting together a comprehensive report. However, I have to wonder whether the test setup truly provided an opportunity to take advantage of the supposedly better quality receivers in the Part 90 radios. My concern is this: The maximum distance over which you could hold usable communications was just 0.6 miles (~1000 meters). That would indicate that the signal was strongly attenuated by something in the signal path. Based on your description of the terrain being flat, the source of the attenuation would most likely be foliage. But, the actual cause of the attestation is not as important as its impact on being able to detect differences in reception. Let's assume, for a simple understanding of the issues involved, that differences in receiver quality appear as a percentage of the usable signal. That is, a good receiver might have 10% greater range than an average receiver. At 10 miles the good receiver would be able to receive a signal at a distance 0.10 mile (160 meters) further than the average receiver. This is an obvious difference and easily noticed by even casual observation. However, at a distance of 0.6 miles, the actual difference in distance is only 0.06 miles (<100 meters). A much shorter difference and one much more likely to go unnoticed. Also, as you have noted, the human ear is not a particularly good device for scientific measurement. So, I would suggest that the conclusion of the tests you conducted should be amended to say that with strongly attenuated signals, the difference between the Wouxun and Part-90 radios was not significant. Quote
mbrun Posted February 15, 2021 Author Report Posted February 15, 2021 Thanks! Very good hands-on. But was it narrow-band or wide-band with the 805G and Motorolas? I'm guessing narrow-band, since you have GXT1000 in the mix. Also, with the GXT1000, did you use the 5W channels or the 0.5W? I'm guessing again the full-power, judging by the results.Fair question. The KG-805G was operating wideband. As for the Motorola’s I will have to confirm with RadioGuy, but at present I believe them to have been configured for wideband. As for the channel used for comparisons 462.6500 was used for all communications between devices under test. 462.6250 was the adjacent channel interference frequency used. The GTX1000 was not evaluated for distance in this round of tests, except for the adjacent channel interference test, as the difference is already known by me. MichaelWRHS965KE8PLM Quote
mbrun Posted February 15, 2021 Author Report Posted February 15, 2021 It's kind of interesting seeing how well the wouxun did, at least in the environment you're working with. Thank you for all the effort you put into this...interesting reading.You’re welcome. Certainly not a lab-grade experiment, but very practical. MichaelWRHS965KE8PLM NCRick 1 Quote
mbrun Posted February 15, 2021 Author Report Posted February 15, 2021 Thank you for doing these tests and putting together a comprehensive report. However, I have to wonder whether the test setup truly provided an opportunity to take advantage of the supposedly better quality receivers in the Part 90 radios. My concern is this: The maximum distance over which you could hold usable communications was just 0.6 miles (~1000 meters). That would indicate that the signal was strongly attenuated by something in the signal path. Based on your description of the terrain being flat, the source of the attenuation would most likely be foliage. But, the actual cause of the attestation is not as important as its impact on being able to detect differences in reception. Let's assume, for a simple understanding of the issues involved, that differences in receiver quality appear as a percentage of the usable signal. That is, a good receiver might have 10% greater range than an average receiver. At 10 miles the good receiver would be able to receive a signal at a distance 0.10 mile (160 meters) further than the average receiver. This is an obvious difference and easily noticed by even casual observation. However, at a distance of 0.6 miles, the actual difference in distance is only 0.06 miles (<100 meters). A much shorter difference and one much more likely to go unnoticed. Also, as you have noted, the human ear is not a particularly good device for scientific measurement. So, I would suggest that the conclusion of the tests you conducted should be amended to say that with strongly attenuated signals, the difference between the Wouxun and Part-90 radios was not significant.First off, you are welcome. Second, you make a very fair statement. There is no doubt that the signals in my environment are in fact very much attenuated. That is why I believe the unreliable/fringe zone from 6/10 to 1.4 miles to be such an important zone. Agreed too that if the fringe area were known to be say, 5 times larger, that finer differences would have been able to be detected. I also believe under laboratory conditions small differences would be detected. But this test was all about the practical, in my environment. In the end, I take no exception to amending the conclusion to clarify. Thanks for your feedback. MichaelWRHS965KE8PLM berkinet and NCRick 2 Quote
Radioguy7268 Posted February 15, 2021 Report Posted February 15, 2021 Fair question. The KG-805G was operating wideband. As for the Motorola’s I will have to confirm with RadioGuy, but at present I believe them to have been configured for wideband. All radios were programmed Wideband, and performance verified prior to shipping with an Aeroflex/IFR 3920. NCRick 1 Quote
mbrun Posted February 15, 2021 Author Report Posted February 15, 2021 All radios were programmed Wideband, and performance verified prior to shipping with an Aeroflex/IFR 3920.Thank you! MichaelWRHS965KE8PLM Quote
Lscott Posted February 15, 2021 Report Posted February 15, 2021 Were the testes performed using the OEM supplied antennas or did you use any aftermarket types? Quote
mbrun Posted February 15, 2021 Author Report Posted February 15, 2021 Were the testes performed using the OEM supplied antennas or did you use any aftermarket types?[/quote] Very good question. Below is a photo of the Motorola equipment used. Both EVX-S24 used the short antennas you see in the picture (one shown attached, one show detached). The VX -261 used the antennas you see attached to the radios in the photo.The EVX-534 used the motorola antenna you see in the image, second from the left. The bent antenna you see on the radio was not used.The two XPR radios used the two remaining antennas you see on the table that are straight. The KG-805G used the manufacturer’s factory default rubber duck. I believe all antennas used with the motorola radios are motorola branded antennas. MichaelWRHS965KE8PLM Quote
MacJack Posted February 15, 2021 Report Posted February 15, 2021 Thank you Michael for taking the time to do this.... As well as Radioguy7268 for providing test radios. I did make it through reading the looong report and very detail. As for the human ears results works for me... If I you can't hear it clear or at all, it fails, I do not need a machine to say how loud or not it is... It all about can I hear and understand the read Constitution. So as a fellow owner of KG-805G with 15 inch Authentic Nagoya NA-771G Handheld GMRS Antenna (15.3 Inch / SMA Female) is a killer setup for our needs. I can reach the repeater with easy. Thanks again guys as well as the comments on wide or narrow band... learned a lot from you all.Jack Quote
jas Posted February 15, 2021 Report Posted February 15, 2021 Excellent post Michael. A great read with a lot of valuable information. Your cutoff distances sure point to a worst case scenario testing, and those are the kind of tests I like to see. I find there is a lot of stuff out there like "I can hit our local repeater from 45 miles with my XYZ HT" possible, but utterly unrealistic, to say the least! With the GSX Midlands if we are on the road .5 miles away and an 18 wheeler gets in between us, it's over! Thanks so much for taking the time! All the best, JAS Quote
mbrun Posted February 15, 2021 Author Report Posted February 15, 2021 You’re welcome Jack. Thank you Michael for taking the time to do this.... As well as Radioguy7268 for providing test radios. I did make it through reading the looong report and very detail. As for the human ears results works for me... If I you can't hear it clear or at all, it fails, I do not need a machine to say how loud or not it is... It all about can I hear and understand the read Constitution. So as a fellow owner of KG-805G with 15 inch Authentic Nagoya NA-771G Handheld GMRS Antenna (15.3 Inch / SMA Female) is a killer setup for our needs. I can reach the repeater with easy. Thanks again guys as well as the comments on wide or narrow band... learned a lot from you all.Jack MichaelWRHS965KE8PLM Quote
mbrun Posted February 15, 2021 Author Report Posted February 15, 2021 You’re welcome JAS. Glad you liked it. Excellent post Michael. A great read with a lot of valuable information. Your cutoff distances sure point to a worst case scenario testing, and those are the kind of tests I like to see. I find there is a lot of stuff out there like "I can hit our local repeater from 45 miles with my XYZ HT" possible, but utterly unrealistic, to say the least! With the GSX Midlands if we are on the road .5 miles away and an 18 wheeler gets in between us, it's over! Thanks so much for taking the time! All the best, JAS MichaelWRHS965KE8PLM Quote
gman1971 Posted February 16, 2021 Report Posted February 16, 2021 Michael, Before anything else is said, thanks for doing this. I am rather surprised the range you got with the XPR7350. Did you had a chance to measure signal RSSI at every point? Did you measure site noise threshold? I would've liked to know what the RSSI readings from the 6550 were. G. Quote
mbrun Posted February 16, 2021 Author Report Posted February 16, 2021 Good Day G. Yes, I was surprised as well. I was certainly expecting I would have experienced more. No, I did not measure RSSI as I do not own any independently trustworthy equipment that would have given me reliable measure. Nor do I have any confidence in the accuracies of the signal level reporting capabilities on the radios themselves to. For certain, I do not trust the meter on the KG-805G. At times 7+ bars while receiving an unintelligible signal does not compute for me The best I can offer with regards to noise in the area is that both my GMRS and amateur HTs signal dance between between 2 and 4 bars when monitor is opened, and that the squelch control on both radios is normally set to 1 and only rarely opens up without some form of intelligible signal present. Michael, Before anything else is said, thanks for doing this. I am rather surprised the range you got with the XPR7350. Did you had a chance to measure signal RSSI at every point? Did you measure site noise threshold? I would've liked to know what the RSSI readings from the 6550 were. G. MichaelWRHS965KE8PLM Quote
gman1971 Posted February 16, 2021 Report Posted February 16, 2021 Well, you actually did have one: The XPR6550 has a very reliable RSSI mode built in. I own several of those radios, all tested with a service monitor, all accurate within a dB to the measured signal. The 6550 gives an actual numeric RSSI readout, not the bars, which are useless unless they are calibrated to a known dB reading. Reading the bars is like eyeballing things out... A 2 and 4 bars out of 5 is a very high noise threshold, but 2 or 4 out of 20 bars is a very low noise threshold. Without knowing the noise threshold on your site its impossible to really know the reasons why the 7350 didn't outperform the other radios. Also, I would've used an SDR cascade to determine the strong off band signals, TV stations, etc... those glow in the dark for an SDR... Thing is, If the noise at your site was really high, it doesn't matter what radio you use, having an effective sensitivity of -120 dBm is useless if the lowest signal you can hear is -96dBm, which in turn, means that the frequency you are using is not suitable for long range comms. Like I've said, you should've done a site analysis, determine which GMRS frequency had the lowest noise threshold, and probably use that. Again, if the noise level RSSI is -96 dB, literally, it won't matter what radio you use, a BF-888s would've probably matched the XPR7350 just fine, and for 9 dollars... Most of those Motorola radios edge the CCRs when he noise threshold is LOW, AND there are strong off band interference, the XPR7550e I have all measured better than -120 dBm effective sensitivity, with a noise floor of -126 dBm. Also, figured I'd say this, but a 50W mobile on the adjacent channel doesn't really qualify as a strong interference. A 250kW TV station on a 1000 foot tower, a few MHz away that is a real interference for a superhet. G. EDIT: Point I am trying to make is that no radio can bend the laws of physics, but the high quality radios are better when the conditions are favorable to be better. The same thing applies to astrophotography, and there are times in which it doesn't matter how many filters you use, or how expensive your equipment, you simply can't picture things b/c the light pollution is, simply put, too strong and too wideband for anything to be effective, especially with the newest LED street lighting that is full spectrum, making most light pollution filters, which block things like Sodium lights etc... those are useless when all you have is LED street light. Quote
mbrun Posted February 17, 2021 Author Report Posted February 17, 2021 Thanks G. Wish I had known about the RSSI meter in the radio. If you are ever looking for a road trip to Cincinnati and some field testing, you know where to find me. Would have loved to have had you around to lend a hand and offer additional insight. If you ever do come down, let’s do it when the temperatures are above freezing. Regards, Well, you actually did have one: The XPR6550 has a very reliable RSSI mode built in. I own several of those radios, all tested with a service monitor, all accurate within a dB to the measured signal. The 6550 gives an actual numeric RSSI readout, not the bars, which are useless unless they are calibrated to a known dB reading. Reading the bars is like eyeballing things out... A 2 and 4 bars out of 5 is a very high noise threshold, but 2 or 4 out of 20 bars is a very low noise threshold. Without knowing the noise threshold on your site its impossible to really know the reasons why the 7350 didn't outperform the other radios. Also, I would've used an SDR cascade to determine the strong off band signals, TV stations, etc... those glow in the dark for an SDR... Thing is, If the noise at your site was really high, it doesn't matter what radio you use, having an effective sensitivity of -120 dBm is useless if the lowest signal you can hear is -96dBm, which in turn, means that the frequency you are using is not suitable for long range comms. Like I've said, you should've done a site analysis, determine which GMRS frequency had the lowest noise threshold, and probably use that. Again, if the noise level RSSI is -96 dB, literally, it won't matter what radio you use, a BF-888s would've probably matched the XPR7350 just fine, and for 9 dollars... Most of those Motorola radios edge the CCRs when he noise threshold is LOW, AND there are strong off band interference, the XPR7550e I have all measured better than -120 dBm effective sensitivity, with a noise floor of -126 dBm. Also, figured I'd say this, but a 50W mobile on the adjacent channel doesn't really qualify as a strong interference. A 250kW TV station on a 1000 foot tower, a few MHz away that is a real interference for a superhet. G. EDIT: Point I am trying to make is that no radio can bend the laws of physics, but the high quality radios are better when the conditions are favorable to be better. The same thing applies to astrophotography, and there are times in which it doesn't matter how many filters you use, or how expensive your equipment, you simply can't picture things b/c the light pollution is, simply put, too strong and too wideband for anything to be effective, especially with the newest LED street lighting that is full spectrum, making most light pollution filters, which block things like Sodium lights etc... those are useless when all you have is LED street light. MichaelWRHS965KE8PLM gman1971 1 Quote
gman1971 Posted February 17, 2021 Report Posted February 17, 2021 Awesome! Thanks Michael, ... and yeah, totally above freezing, and no snow... we are covered in like 4 feet of snow around the house here!! In Wisconsin hahaha... G. Thanks G.Wish I had known about the RSSI meter in the radio.If you are ever looking for a road trip to Cincinnati and some field testing, you know where to find me. Would have loved to have had you around to lend a hand and offer additional insight. If you ever do come down, let’s do it when the temperatures are above freezing. Regards,MichaelWRHS965KE8PLM Quote
haneysa Posted February 22, 2021 Report Posted February 22, 2021 I have some Part 90 HTs, and many models of the "bubble-pack" radios, including some legacy Motorolas with repeater capability, as well as the KG-805g, and the GMRS-V1. The 805g is well worth the extra cost over any of the bubble-pack radios. The 805g beats the GMRS-V1 as well. The 805G is repeater compatible, and you can program many custom channels. The 805g can utilize better HT antennas, or external antennas. I do not have a service monitor, but field-testing leads to to believe that the 805g has a much better front end than most CCR and the bubblepacks. For those who are stickler's for FCC rule compliance, the 805g is type certified for GMRS. I do have some part 90/95A radios from Kenwood and Icom, but many of the Part 90 radios being used by GMRS operators are not part 95, and some may object to their use. I don't have a problem with anyone using them. The way I see it, the purpose of the FCC rules is to prevent harmful interference and to let as many people as possible use the spectrum. It makes no logical sense to limit someone's choices, as long as the operator does not misuse their equipment to the detriment of someone else (No Harm, No Foul). I really appreciate the efforts of the tester. More info is always good. AdmiralCochrane 1 Quote
wayoverthere Posted February 22, 2021 Report Posted February 22, 2021 I have some Part 90 HTs, and many models of the "bubble-pack" radios, including some legacy Motorolas with repeater capability, as well as the KG-805g, and the GMRS-V1. The 805g is well worth the extra cost over any of the bubble-pack radios. The 805g beats the GMRS-V1 as well. The 805G is repeater compatible, and you can program many custom channels. The 805g can utilize better HT antennas, or external antennas. I do not have a service monitor, but field-testing leads to to believe that the 805g has a much better front end than most CCR and the bubblepacks. For those who are stickler's for FCC rule compliance, the 805g is type certified for GMRS. I do have some part 90/95A radios from Kenwood and Icom, but many of the Part 90 radios being used by GMRS operators are not part 95, and some may object to their use. I don't have a problem with anyone using them. The way I see it, the purpose of the FCC rules is to prevent harmful interference and to let as many people as possible use the spectrum. It makes no logical sense to limit someone's choices, as long as the operator does not misuse their equipment to the detriment of someone else (No Harm, No Foul). I really appreciate the efforts of the tester. More info is always good.I think it comes down to the low bar to entry; since there's no knowledge requirement for a gmrs license, this is the FCC's way of giving a user with zero knowledge a way to know they're using compliant equipment, and (in theory) not throwing spurious emissions all over the spectrum. Ham, on the other hand, has some level of knowledge required, so they allow more freedom on equipment, with the burden on the operator to ensure the quality of their own equipment. AdmiralCochrane 1 Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.