marcspaz Posted November 2, 2022 Report Share Posted November 2, 2022 5 hours ago, KAF6045 said: Just to fill in blanks, I believe the only HF band (unless you count 6m as HF rather than VHF) that permits FM is 10m. Considering that common FM deviation for Amateur likely requires a 20-25kHz bandwidth, and the 20m voice region is only 200kHz wide, FM mode would allow for less than 10 non-interfering QSOs. Amateur AM mode is only 6kHz wide, SSB about 2.7kHz wide -- and both of those modes don't have capture effect, so it is possible to have overlapping QSOs which one can adjust filters to minimize interference (lack of capture effect is why aviation bands don't use FM -- it permits a distress call to be heard through an ongoing communication). This is not accurate. You can use any modulation type (including digital) on any HF band except 60m. Also, there is extremely limited bandwidth restrictions on all HF bands (depends on modulation type) except on 60m, which is heavily restricted. SteveShannon 1 Quote Link to comment Share on other sites More sharing options...
KAF6045 Posted November 2, 2022 Report Share Posted November 2, 2022 17 hours ago, marcspaz said: This is not accurate. You can use any modulation type (including digital) on any HF band except 60m. Also, there is extremely limited bandwidth restrictions on all HF bands (depends on modulation type) except on 60m, which is heavily restricted. Apparently a change (or not covered by my old license manuals) (first is FCC regs, second is Wikipedia) Quote The following standards and limitations apply to transmissions on the frequencies specified in § 97.305(c) of this part. (1) No angle-modulated emission may have a modulation index greater than 1 at the highest modulation frequency. Quote Frequency modulation can be classified as narrowband if the change in the carrier frequency is about the same as the signal frequency, or as wideband if the change in the carrier frequency is much higher (modulation index > 1) than the signal frequency.[7] For example, narrowband FM (NFM) is used for two-way radio systems such as Family Radio Service, in which the carrier is allowed to deviate only 2.5 kHz above and below the center frequency with speech signals of no more than 3.5 kHz bandwidth. So basically extreme NFM for most bands... 10m seems to have a small section that would allow regular FM (note NO (1) restriction). It's the only band that ARRL band plans explicitly list an FM section. Quote 10 m 29.0-29.7 MHz Phone, image (2). marcspaz 1 Quote Link to comment Share on other sites More sharing options...
WRUE951 Posted November 6, 2022 Report Share Posted November 6, 2022 On 3/7/2022 at 7:42 AM, WRPN896 said: I heard this morning on the net that the FCC does not allow newly Repeaters is this 100% Correct? DE WRPN896 Thats flat out BS... Was the guys first name 'Joe' by any chance? Quote Link to comment Share on other sites More sharing options...
Lscott Posted November 6, 2022 Report Share Posted November 6, 2022 People need to read the rules before believing some of the stuff they get on the 'net. The rules don't limit the number of repeaters, just the number of frequency pairs, GMRS "main channels", they can use, currently the rules list 8 RX and 8 TX frequencies. As a side note I don't see anything that requires the RX and TX frequencies to be exactly 5MHz apart either so long as you use one of the 8 TX and one of the RX ones listed in the rules. https://www.ecfr.gov/current/title-47/chapter-I/subchapter-D/part-95/subpart-E/section-95.1763 You can have as many repeaters as you want on a frequency pair so long as the frequency is shared with other users. fe2o3 1 Quote Link to comment Share on other sites More sharing options...
WRKC935 Posted November 6, 2022 Report Share Posted November 6, 2022 OK, here's what is being misunderstood here. There was a time the the FCC issued repeater pairs to new GMRS license applicants. These were from the 8 repeater pairs laiid out in the rules pertaining to the service. You typically would get two pairs to use and this was to more or less act as 'coordination' for frequency use. That was stopped and all license holders had unrestricted access to ALL 8 pairs to be put into use or to be used to access other repeaters. Repeaters back then were more 'private use' that what we are doing now with the service where a few put up big repeater systems that the rest enjoy the coverage of. Some charge for that access and others don't. But the bigger point is that we all can use ALL the repeater pairs and WE as license holders are now responsible to do our own frequency coordination. Now that isn't a bad thing as long as both parties involved are willing to work with each other. At the point one or both parties decide to not be flexible, then it turns into a mess that the FCC will NOT get involved in unless the regulations on the books are broken. At that point the pull the license of the problem individual or individuals and the problem is again solved. Guessing this is the basis of what you are understanding with the statement you made. It's partly correct but not close to the truth. No big deal. We all are learning every day. And hope to keep learning. gortex2 1 Quote Link to comment Share on other sites More sharing options...
BoxCar Posted November 6, 2022 Report Share Posted November 6, 2022 Just because the rules do not say you cannot do something, they also don't say you can either. By convention, UHF repeater pairs are 5 MHz apart for uniformity. If you use a non-standard split you need to monitor both input frequencies to prevent interference to the other users. Rules DO state you are to avoid causing harmful interference to others. UncleYoda 1 Quote Link to comment Share on other sites More sharing options...
MichaelLAX Posted November 6, 2022 Report Share Posted November 6, 2022 23 minutes ago, BoxCar said: Just because the rules do not say you cannot do something, they also don't say you can either. By convention, UHF repeater pairs are 5 MHz apart for uniformity. If you use a non-standard split you need to monitor both input frequencies to prevent interference to the other users. Rules DO state you are to avoid causing harmful interference to others. WoW: and you criticize some of the things I like to discuss here??? Let's unpack this: With only 8 repeater channels available for GMRS you are proposing what? That the rules do not prevent split frequencies so that your repeater potentially interferes with 2 of those 8 channels? "You need to monitor both input frequencies..." - Do you mean you must monitor both the input frequency and the split output frequency? Sorry, but I am missing the advantage, if any, of this idea. But I like that you propose it here! Quote Link to comment Share on other sites More sharing options...
Lscott Posted November 6, 2022 Report Share Posted November 6, 2022 9 minutes ago, BoxCar said: Just because the rules do not say you cannot do something, they also don't say you can either. By convention, UHF repeater pairs are 5 MHz apart for uniformity. If you use a non-standard split you need to monitor both input frequencies to prevent interference to the other users. Rules DO state you are to avoid causing harmful interference to others. If you wanted to keep someone from using your repeater with the cheap frequency preprogrammed radios then picking a non standard frequency split would do the trick. Since the rules don't require one to use a 5 MHz split you're free to pick from any of the 8 TX and any of the 8 RX frequencies for the repeater. The only radios that will work in that case are modified radios and commercial Part 95 certified radios which you can independently set the TX and RX frequencies. Also the same idea will work to frustrate simplex jammers. Radio one will TX on F1 and RX on F2. The other radio will TX on F2 and RX on F1. Both frequencies are legal simplex channels. Each user can have several channels programmed up with different combinations of TX and RX simplex frequencies and switch between them, memory channels, as conditions demand. To do this with more that two radios is not as simple and would likely require some method to scan several channels very rapidly, a programmable home or priority channel feature etc. As far as I can see there is nothing in the rules that prohibits this either. So long as your operation is not causing interference, as you pointed out, it should be OK. Quote Link to comment Share on other sites More sharing options...
SteveShannon Posted November 6, 2022 Report Share Posted November 6, 2022 1 hour ago, Lscott said: If you wanted to keep someone from using your repeater with the cheap frequency preprogrammed radios then picking a non standard frequency split would do the trick. Since the rules don't require one to use a 5 MHz split you're free to pick from any of the 8 TX and any of the 8 RX frequencies for the repeater. The only radios that will work in that case are modified radios and commercial Part 95 certified radios which you can independently set the TX and RX frequencies. Also the same idea will work to frustrate simplex jammers. Radio one will TX on F1 and RX on F2. The other radio will TX on F2 and RX on F1. Both frequencies are legal simplex channels. Each user can have several channels programmed up with different combinations of TX and RX simplex frequencies and switch between them, memory channels, as conditions demand. To do this with more that two radios is not as simple and would likely require some method to scan several channels very rapidly, a programmable home or priority channel feature etc. As far as I can see there is nothing in the rules that prohibits this either. So long as your operation is not causing interference, as you pointed out, it should be OK. Actually the lowest caste radio, the Baofeng uv5r, can easily be programmed to follow any splits, frequencies, tones, or possibly even bands. In fact that flexibility is exactly why some people like them. Quote Link to comment Share on other sites More sharing options...
BoxCar Posted November 6, 2022 Report Share Posted November 6, 2022 1 hour ago, MichaelLAX said: WoW: and you criticize some of the things I like to discuss here??? Let's unpack this: With only 8 repeater channels available for GMRS you are proposing what? That the rules do not prevent split frequencies so that your repeater potentially interferes with 2 of those 8 channels? "You need to monitor both input frequencies..." - Do you mean you must monitor both the input frequency and the split output frequency? Sorry, but I am missing the advantage, if any, of this idea. But I like that you propose it here! Michael, I'm a former NATIONAL frequency coordinator for Parts 90.20 and was a member of both the Land Mobile Communications Council and the Public Safety Communications Councils besides being a member of the FCC's Communications Information Security and Reliability Federal Advisory panel. I did part 90.35 and 101 coordination. I have written petitions to the FCC for rule changes and had them implemented. One petition initiated the first rule change in 35 years. I was an instrumental part of obtaining the Band 14 allocation at 800 MHZ among other items in my career. Now, what have you done that provides you with your qualifications? marcspaz, Radioguy7268, Lscott and 1 other 2 2 Quote Link to comment Share on other sites More sharing options...
Lscott Posted November 6, 2022 Report Share Posted November 6, 2022 2 hours ago, Sshannon said: Actually the lowest caste radio, the Baofeng uv5r, can easily be programmed to follow any splits, frequencies, tones, or possibly even bands. In fact that flexibility is exactly why some people like them. It's also not Part 95 certified. I'm talking about radios certified to use on GMRS. Radioguy7268 and gortex2 2 Quote Link to comment Share on other sites More sharing options...
MichaelLAX Posted November 6, 2022 Report Share Posted November 6, 2022 On 11/6/2022 at 7:24 AM, BoxCar said: Now, what have you done that provides you with your qualifications? I must admit: I have never proposed a split frequency shift for the 8 repeater channels of GMRS. You have me there! Quote Link to comment Share on other sites More sharing options...
SteveShannon Posted November 6, 2022 Report Share Posted November 6, 2022 6 hours ago, Lscott said: Since the rules don't require one to use a 5 MHz split you're free to pick from any of the 8 TX and any of the 8 RX frequencies for the repeater. The only radios that will work in that case are modified radios and commercial Part 95 certified radios which you can independently set the TX and RX frequencies. 1 hour ago, Lscott said: 4 hours ago, Sshannon said: Actually the lowest caste radio, the Baofeng uv5r, can easily be programmed to follow any splits, frequencies, tones, or possibly even bands. In fact that flexibility is exactly why some people like them. It's also not Part 95 certified. I'm talking about radios certified to use on GMRS. No, that’s not what you said (first quote) Quote Link to comment Share on other sites More sharing options...
Lscott Posted November 6, 2022 Report Share Posted November 6, 2022 28 minutes ago, Sshannon said: No, that’s not what you said (first quote) You advocating the use of uncertified radios on GMRS? I'm not. Also this part I guess you missed, "the cheap frequency preprogrammed radios", does not apply to the UV5R type radio since it is freely frequency programmable. Radios such as the 805, 905, 935 and similar from other manufactures etc. have preprogrammed TX and RX frequencies you can't modify and are commonly used for GMRS. Quote Link to comment Share on other sites More sharing options...
wayoverthere Posted November 7, 2022 Report Share Posted November 7, 2022 9 hours ago, Lscott said: You advocating the use of uncertified radios on GMRS? I'm not. Also this part I guess you missed, "the cheap frequency preprogrammed radios", does not apply to the UV5R type radio since it is freely frequency programmable. Radios such as the 805, 905, 935 and similar from other manufactures etc. have preprogrammed TX and RX frequencies you can't modify and are commonly used for GMRS. sorry to rain on that point, but I can at least speak to the 805g...Wouxun's unmodified software will allow you to combine any of the GMRS RX frequencies with ANY of the in-bounds transmit frequencies...the lockdown for part 95 certification is strictly software based (as i've alluded to elsewhere), it only gives you in bounds frequencies to choose from the drop-down that is the TX frequency column. I have a couple screenshots (that successfully loaded to the radio) with 462.550 as the RX, and both 467.725 and 467.7125 as associated TX frequencies. I also grabbed one showing the drop-down for the TX frequency column. SteveShannon 1 Quote Link to comment Share on other sites More sharing options...
Lscott Posted November 7, 2022 Report Share Posted November 7, 2022 8 hours ago, wayoverthere said: sorry to rain on that point, but I can at least speak to the 805g...Wouxun's unmodified software will allow you to combine any of the GMRS RX frequencies with ANY of the in-bounds transmit frequencies...the lockdown for part 95 certification is strictly software based (as i've alluded to elsewhere), it only gives you in bounds frequencies to choose from the drop-down that is the TX frequency column. I have a couple screenshots (that successfully loaded to the radio) with 462.550 as the RX, and both 467.725 and 467.7125 as associated TX frequencies. I also grabbed one showing the drop-down for the TX frequency column. So in the case of that radio it does appear you can mix TX and RX frequencies so I off base on that one. I guess I should be more careful about making statements on radios I haven't really used. Thanks for pointing it out. In any case one can use that radio and try out the split frequency operation for fun. Quote Link to comment Share on other sites More sharing options...
MichaelLAX Posted November 7, 2022 Report Share Posted November 7, 2022 Is this what you are talking about: Cross Channel 2-in-1 Duplex Repeater Controller Quote Link to comment Share on other sites More sharing options...
WRKC935 Posted November 8, 2022 Report Share Posted November 8, 2022 On 11/6/2022 at 7:50 AM, BoxCar said: Just because the rules do not say you cannot do something, they also don't say you can either. By convention, UHF repeater pairs are 5 MHz apart for uniformity. If you use a non-standard split you need to monitor both input frequencies to prevent interference to the other users. Rules DO state you are to avoid causing harmful interference to others. I actually know of at least one system that does this. Down in Tampa there is a GMRS repeater that The input frequency happens to be the same channel that some cruise ship uses for in dock operations and when they come in it tears up the repeater access since the tower is right on the water near the port. That repeater has two Input frequencies. The owner switches between the two receivers as needed to keep the simplex radio operations off the repeater when the ship is in port. Not sure if it's FRS or GMRS being used but I know it causes him problems and that is how it was dealt with. Quote Link to comment Share on other sites More sharing options...
marcspaz Posted November 8, 2022 Report Share Posted November 8, 2022 I am not a lawyer nor a law enforce officer,, but I spent a long time studying constitutional law and criminal justice. Almost a decade. I have a high degree of confidence in stating that if something is not explicitly prohibited, it's assumed legal. There are very, very limited exceptions where guilt is assumed until proven otherwise. In those cases (statutes) it is very clearly defined as a prima facie prohibited act until determined otherwise allowed. I am unaware of any law that has actual assumptions. AdmiralCochrane, SteveShannon and TOM47 3 Quote Link to comment Share on other sites More sharing options...
Lscott Posted November 8, 2022 Report Share Posted November 8, 2022 20 hours ago, MichaelLAX said: Is this what you are talking about: Cross Channel 2-in-1 Duplex Repeater Controller That's what some people have used for building a simple repeater using two separate radios. Best use of one is for a cross band repeater. Lets say between 2M and 70cm bands for Ham use. You can run two low power radios into one antenna using a duplexer. https://mfjenterprises.com/products/mfj-916b I believe you can get about 60db isolation between to two ports with the above model. Quote Link to comment Share on other sites More sharing options...
gscanter Posted February 6, 2023 Report Share Posted February 6, 2023 I just want more UHF spectrum to set up new repeaters outside the normal 8 sets Quote Link to comment Share on other sites More sharing options...
SteveShannon Posted February 6, 2023 Report Share Posted February 6, 2023 3 minutes ago, gscanter said: I just want more UHF spectrum to set up new repeaters outside the normal 8 sets Sorry. That’s all we get. TOM47 and gortex2 2 Quote Link to comment Share on other sites More sharing options...
gortex2 Posted February 6, 2023 Report Share Posted February 6, 2023 1 hour ago, gscanter said: I just want more UHF spectrum to set up new repeaters outside the normal 8 sets They have that but its called Amateur Radio. SteveShannon and tweiss3 2 Quote Link to comment Share on other sites More sharing options...
WRQC527 Posted February 6, 2023 Report Share Posted February 6, 2023 26 minutes ago, gortex2 said: They have that but its called Amateur Radio. Yep, and the problem with that is, for example here in Southern California, ham repeater pairs are hard to get. TASMA and SCRRBA coordinate repeaters, and there are already so many that adding new ones is darn near impossible. Quote Link to comment Share on other sites More sharing options...
wrci350 Posted February 6, 2023 Report Share Posted February 6, 2023 It is highly unlikely that more bandwidth will ever be added to the 70cm ham band or to GMRS. Quote Link to comment Share on other sites More sharing options...
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