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WRVG593
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Hi there, I recently gotten into radios and wanted to get into amatuer radio. My question is if you use let's say, 130 mhz to 220 mhz, or 400 to 520, can you use any of the frequencies not currently in use? For example, if I plug in the frequency 158.452 can I just transmit assuming there's no other traffic (ems, police, fire, etc.) Or are there very specific frequencies that I can transmit on (repeaters only) or can I simplex transmit to people? I know it sounds funny but I'm really interested in amatuer and just haven't started studying yet. I love learning from this site and would appreciate all help. 

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6 minutes ago, WRVG593 said:

Hi there, I recently gotten into radios and wanted to get into amatuer radio. My question is if you use let's say, 130 mhz to 220 mhz, or 400 to 520, can you use any of the frequencies not currently in use? For example, if I plug in the frequency 158.452 can I just transmit assuming there's no other traffic (ems, police, fire, etc.) Or are there very specific frequencies that I can transmit on (repeaters only) or can I simplex transmit to people? I know it sounds funny but I'm really interested in amatuer and just haven't started studying yet. I love learning from this site and would appreciate all help. 

Short answer: No, you can not. You are only allowed to used frequencies that are allocated for Amateur Radio (if you have Amateur Lincese). 158.452 is not one of them.

Long answer: For starters, see the frequency allocations: https://en.wikipedia.org/wiki/Amateur_radio_frequency_allocations  and  http://www.arrl.org/frequency-allocations Or in graphic form: http://www.arrl.org/graphical-frequency-allocations

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6 minutes ago, axorlov said:

Short answer: No, you can not. You are only allowed to used frequencies that are allocated for Amateur Radio (if you have Amateur Lincese). 158.452 is not one of them.

Long answer: For starters, see the frequency allocations: https://en.wikipedia.org/wiki/Amateur_radio_frequency_allocations  and  http://www.arrl.org/frequency-allocations Or in graphic form: http://www.arrl.org/graphical-frequency-allocations

Okay let me reiterate in a different way. I understand the bands now. I guess my actual question then would be between 144 and 148 can I just transmit simplex and call it a day? Or do I have to be on a recognized repeater? Same with 420-450 (except gmrs/frs). 

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14 minutes ago, WRVG593 said:

Okay let me reiterate in a different way. I understand the bands now. I guess my actual question then would be between 144 and 148 can I just transmit simplex and call it a day? Or do I have to be on a recognized repeater? Same with 420-450 (except gmrs/frs). 

That is little more complex. The short answer is: Yes, you can transmit simplex FM (I presume) between 144 and 148 MHz.

But by blindly doing so, you will piss off quite some number of people, depending on your location and how the air is congested. While the Amateur Band Allocations is the Law, there is also a gentleman's agreement called a Band Plan. Here are Band Plan in US: http://www.arrl.org/band-plan  Look for 2m. They do vary locally, depending on how many users doing what exactly. Speaking of 2m, there is a national calling frequency (FM) 146.52 MHz and several frequency ranges dedicated for FM simplex. These are not the law, but an agreement.

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4 hours ago, axorlov said:

there is also a gentleman's agreement called a Band Plan

This gentleman's agreement is so universally known and adhered to that it's actually built in to a lot of transceivers. If you select a certain frequency on a 2-meter tranceiver, for example, it will automatically know if it's a repeater frequency that needs a positive or negative offset, or if it's a simplex frequency. Same with HF radios. Traditionally, different bands operate on either upper or lower sideband. Radios will automatically transmit on these upper or lower sidebands depending on the band.

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12 hours ago, WRQC527 said:

This gentleman's agreement is so universally known and adhered to that it's actually built in to a lot of transceivers

 

This is true…in many cases. However, as stated earlier, the band plans do vary locally. As an example of this, many years ago, I had a group of ham radio friends that operated simplex FM on 146.400. That frequency was designated as a simplex frequency in our coordinated band plan. It also appears on modern amateur transceivers with no pre-configured offset, nor does any other frequency offset to 146.400.

At some point, we received emails from Riley Hollingsworth, who was the legal counsel for the FCC at the time. Hollingsworth stated in the email that he had received complaints regarding interference to a repeater over 160 miles south of us, in another state, and asked that we contact him, in order to get more information in the matter. Each of us talked to Hollingsworth, and explained how we used the frequency (simplex FM operation, either mobile or base, how much power, antennas used, etc.) 

The issue at hand was this…the repeater to our south had numerous input sites, and one of those inputs was about 90 miles away, on a tall tower, and the repeater had no PL tone on it. Further, the output of the repeater was on 147.000, and the input was on 146.400, the simplex frequency in our region.

When Hollingsworth told us of the issue, he asked we do some testing, and we did tests and found that a 5 watt HT signal from a third floor apartment in an urban area, 90+ miles away, could hit this input with mild band enhancement.

Now if you take your modern amateur 2m transceiver and look at the “automatic repeater shift” setting for 147.000, you will find it will indicate a “+” (positive) offset. However, the repeater in question used a negative offset, putting the input on a designated simplex frequency in our coordinating region. I recall mentioning this to Hollingsworth during our phone call, stating that my FCC approved equipment puts me on simplex on 146.400, and that the input to 147.000 would be 147.600 on my Yaesu radio.

Upon completion of his investigation, Hollingsworth told us that we were operating correctly and to continue doing what we were doing. We were operating correctly and in compliance. The repeater owner had been told many times to tone the input to the repeater, as he had filed other complaints with the FCC regarding the same matter. The FCC determined it was unreasonable for a high profile repeater to operate in this manner, when in fact, all FCC approved gear will indicate a positive offset for 147.000, and tone access has been an established convention for nearly two decades at this point in time. The repeater owner had been advised to tone his repeater several times by the FCC, but refused to do so.

So here is a case where the band plan in one location was different from that in a neighboring state, as conceived by “coordination councils”, and the typical ham transceiver would have a different repeater shift from what was in use.

And to put the cherry on top, we contacted the coordinating councils in the two regions about this matter while the FCC was doing it’s investigation, and both council bodies responded with “you are wrong. You can’t interfere with a repeater, so you must change frequency”. These “councils” were, in fact, wrong, and went away with their tails between their legs when presented with the findings from the FCC. 

it is always best to understand the rules of amateur radio, and the conventions of operation within your region, so that you have the FCC on your side, and you can educate arrogant hams who “think” they know what they are talking about. 

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48 minutes ago, WRAM370 said:

 

This is true…in many cases. However, as stated earlier, the band plans do vary locally. As an example of this, many years ago, I had a group of ham radio friends that operated simplex FM on 146.400. That frequency was designated as a simplex frequency in our coordinated band plan. It also appears on modern amateur transceivers with no pre-configured offset, nor does any other frequency offset to 146.400.

At some point, we received emails from Riley Hollingsworth, who was the legal counsel for the FCC at the time. Hollingsworth stated in the email that he had received complaints regarding interference to a repeater over 160 miles south of us, in another state, and asked that we contact him, in order to get more information in the matter. Each of us talked to Hollingsworth, and explained how we used the frequency (simplex FM operation, either mobile or base, how much power, antennas used, etc.) 

The issue at hand was this…the repeater to our south had numerous input sites, and one of those inputs was about 90 miles away, on a tall tower, and the repeater had no PL tone on it. Further, the output of the repeater was on 147.000, and the input was on 146.400, the simplex frequency in our region.

When Hollingsworth told us of the issue, he asked we do some testing, and we did tests and found that a 5 watt HT signal from a third floor apartment in an urban area, 90+ miles away, could hit this input with mild band enhancement.

Now if you take your modern amateur 2m transceiver and look at the “automatic repeater shift” setting for 147.000, you will find it will indicate a “+” (positive) offset. However, the repeater in question used a negative offset, putting the input on a designated simplex frequency in our coordinating region. I recall mentioning this to Hollingsworth during our phone call, stating that my FCC approved equipment puts me on simplex on 146.400, and that the input to 147.000 would be 147.600 on my Yaesu radio.

Upon completion of his investigation, Hollingsworth told us that we were operating correctly and to continue doing what we were doing. We were operating correctly and in compliance. The repeater owner had been told many times to tone the input to the repeater, as he had filed other complaints with the FCC regarding the same matter. The FCC determined it was unreasonable for a high profile repeater to operate in this manner, when in fact, all FCC approved gear will indicate a positive offset for 147.000, and tone access has been an established convention for nearly two decades at this point in time. The repeater owner had been advised to tone his repeater several times by the FCC, but refused to do so.

So here is a case where the band plan in one location was different from that in a neighboring state, as conceived by “coordination councils”, and the typical ham transceiver would have a different repeater shift from what was in use.

And to put the cherry on top, we contacted the coordinating councils in the two regions about this matter while the FCC was doing it’s investigation, and both council bodies responded with “you are wrong. You can’t interfere with a repeater, so you must change frequency”. These “councils” were, in fact, wrong, and went away with their tails between their legs when presented with the findings from the FCC. 

it is always best to understand the rules of amateur radio, and the conventions of operation within your region, so that you have the FCC on your side, and you can educate arrogant hams who “think” they know what they are talking about. 

Wow. 616 words. I think this is a new mygmrs record. 

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19 hours ago, WRVG593 said:

Okay let me reiterate in a different way. I understand the bands now. I guess my actual question then would be between 144 and 148 can I just transmit simplex and call it a day? Or do I have to be on a recognized repeater? Same with 420-450 (except gmrs/frs). 

You may communicate using simplex; you don’t need to use a repeater, but as others have pointed out you should adhere to the band plan established in your area.  A local amateur radio club can help you find out what that is. If one hasn’t been established locally, then you should use this one from the ARRL site.  Notice that Simplex appears in three or four different portions of this band plan, not the full 144-148:

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19 hours ago, axorlov said:

That is little more complex. The short answer is: Yes, you can transmit simplex FM (I presume) between 144 and 148 MHz.

But by blindly doing so, you will piss off quite some number of people, depending on your location and how the air is congested. While the Amateur Band Allocations is the Law, there is also a gentleman's agreement called a Band Plan. Here are Band Plan in US: http://www.arrl.org/band-plan  Look for 2m. They do vary locally, depending on how many users doing what exactly. Speaking of 2m, there is a national calling frequency (FM) 146.52 MHz and several frequency ranges dedicated for FM simplex. These are not the law, but an agreement.

Not to mention...unless youve prearranged with someone else to meet there, it may not do much good to look for simplex contacts in a portion of the band where others aren't expecting to find simplex contacts...if that makes sense.

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On 2/6/2023 at 4:09 PM, WRVG593 said:

Okay let me reiterate in a different way. I understand the bands now. I guess my actual question then would be between 144 and 148 can I just transmit simplex and call it a day? Or do I have to be on a recognized repeater? Same with 420-450 (except gmrs/frs). 

Another complexity to take into account: the bandwidth of the mode you are using.

A radio with +/-5.0kHz deviation would need to be at 144.005MHz (minimum) to keep the deviation edge at 144.000MHz, any lower and you are transmitting outside of the band. Similar for the upper end (147.995MHz).

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  • 3 weeks later...

That is incorrect. To get occupied BW, you need to multiply Deviation x Audio BW. For a typical 3k audio bandpass, that would be 15 kHz. Standard FM of 5k is usually setup for 20 or 25 kHz channel spacing. N-FM is setup on 12.5 or 10k channel spacing. 

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10 hours ago, WRQH488 said:

That is incorrect. To get occupied BW, you need to multiply Deviation x Audio BW. For a typical 3k audio bandpass, that would be 15 kHz. Standard FM of 5k is usually setup for 20 or 25 kHz channel spacing. N-FM is setup on 12.5 or 10k channel spacing. 

 

It looks like you are trying to use the Carlson Rule.  Carson’s Rule is an estimation of the maximum bandwidth. The bandwidth will be proportionate with the audio signal amplitude, but with a maximum bandwidth estimated by Carson’s Rule, the bandwidth would be 2(5 kHz + 3 kHz) = 16KHz, not 15KHz.

Unfortunately, on the VHF amateur bands, channel spacing is 15KHz across most of the country.  This leads to a lot of bleed-over when there are conversations happening on adjacent channels.  There are about 10 states that use 20KHz, which is better.  UHF is 12.5KHz for NFM and 25KHz for FM on the amateur bands and GMRS, which is a bit more comfortable with regard to prevent/avoiding interference. 

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5 hours ago, marcspaz said:

Unfortunately, on the VHF amateur bands, channel spacing is 15KHz across most of the country. 

Who ever came up with that had a major brain F--t. In all fairness it was likely done due to the band getting crowded with all sorts of modes and specific uses. With only 4MHz of bandwidth that can get allocated quick.

On UHF the usual 430-450 gives one 20 MHz of bandwidth to use. South of Line-A it's 420-450. For example the vast majority of digital voice operations you'll find on UHF. Most likely due to more room to accommodate it.

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