Frequencies available for Ham simplex - Digital and Analog

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human8472

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My wife and I both have our technician level licenses. What simplex frequencies are we allowed to use for simplex conversations?

For example if I look at the ARRL band plan for 2 meters and it shows some simplex channel groups:

146.40-146.58

147.42-147.57

Can we select any frequencies in these ranges for simplex communications? Are we free to use digital and analog with any frequency in these ranges that are not already in use? Thank you.
 

human8472

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Thank you for that information.

146.400 146.415 146.430 146.445 146.460 146.475

It seems that they list all the frequencies in the range by 15 KHz spacing. With digital narrowband having a spacing of 6.25 KHz would that open up more channels ?
 

nd5y

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It seems that they list all the frequencies in the range by 15 KHz spacing. With digital narrowband having a spacing of 6.25 KHz would that open up more channels ?
No because almost everybody else is still using 16-20 kHz wide FM on receivers with filter bandwidths that can be up to 30 kHz wide. If you run a narrow digital mode like NXDN or even CW on a a frequency that is only a few kHz away from somebody running FM you will both cause interference to eachother.

Legally you can operate simplex on any frequency that your license class allows and that Part 97 allows as long as you don't cause interference. If you pick the wrong frequency you could interfere with repeaters, point-to-point links or other stuff.

In most areas it's usually safe to operate simplex on 2 meters between 144.9-145.10, 145.51-145.79, 146.41-146.6 and 147.40-147.59 although in some areas some of those frequencies could be used for repeater inputs or outputs, RoIP nodes, or packet radio.

Where are you located? Check your state or regional frequency coordinator and see if they have VHF/UHF band plans for your area.
 
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popnokick

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Proceed carefully before you light up VHF / UHF simplex frequencies with digital voice modes (e.g. D-Star, DMR, C4FM, P25). It can range from mildly aggravating to completely intolerable for some users to hear the buzzing digital wasp's nest on a frequency "thought" to be analog simplex.

The ARRL Band Plan doesn't address all the details / modes / specific frequencies used for VHF / UHF simplex communications. One of several places to find more info is here -
https://sera.org/index.php/frequency-coordination/frequency-utilization-plans-revision-band-plans/
Because this info is subject to change I didn't quote specific frequencies, but did quote the following -

"Of particular note, some simplex frequencies listed in the ARRL Band Plan may, or may not, be repeater inputs in some areas as our coordinators make changes to better suit their area."

"Another example is the different assignments of spectrum for FM Voice Simplex, and Packet/ Digital Simplex. Repeater users as well as packet/digital users are asked to honor these frequencies by utilizing the ones specifically assigned to the particular mode they are operating."

"All coordination and spectrum management by coordinators is based on “gentlemen’s agreements” and usage by all hams whether they are operators using FM repeaters, simplex, or packet digital using duplex packet modes or simplex. For spectrum management to continue to work successfully around the nation, operators must take the responsibility of working only frequencies in the mode in which that frequency is assigned."

"This prevents chaos and interference and arguments. All modes of amateur operations are well represented by frequency spectrum assignments on most all bands. Using only those frequencies assigned prevents unwanted problems."

Finally, here are the "most common" simplex frequencies I've seen used / recommended for various digital modes -
D-Star (2M) - 145.670
D-Star (70cm) - 440.9125 440.9250 440.9375 440.9500 440.9875 441.0000 * 441.0125 441.0250 441.0625 441.0750 441.0875 441.1000 441.1375 441.1500 441.1625 441.1750
* 441.000 is the National Digital Simplex Calling Frequency
DMR (2M) - 145.510, 145.790
DMR (70cm) - 441.000, 446.500, 446.075, 433.450
(.... and I'll let someone else fill-in with C4FM or other modes)
 

popnokick

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Thanks Tom for pointing out to all reading that the SERA plan is but ONE regional plan and that other plans have variations based upon geography. Sorry if I didn't make that clear in what I wrote.
 

AK9R

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Band plans, no matter who publishes them, are just guidelines or "gentlemen's agreements". The ARRL publishes a band plan that tries to incorporate typical operating practices across the country. But, your state or regional frequency coordinator ls likely to have a slightly different band plan that would be more appropriate to use in your particular area. Even then, you are likely to find users who don't follow the band plan. Listening first for other activity on your frequency of choice is always a good policy.
 
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DaveNF2G

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If you are (un)lucky enough to live in New York, you need to find out which coordinating body covers your part of the state. There are no statewide coordinators here.
 

zz0468

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To the OP, the salient point of all this is that the appropriate frequency for you to operate simplex on is subject to local agreement. Failure to follow local custom could find you operating on someone's coordinated repeater input.

The ARRL bandplan is useless except in the case of areas that have adopted it for their local bandplan.
 

k6cpo

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The way I see it is that as long as you're not operating on some repeater's input or output frequency, using simplex for a digital mode is about the same as using it for analog FM. If you listen first and make sure there is no other activity on the frequency, then you should be fine. If some other operator gets his shorts in a wad because you're using digital on what he feels should be an analog frequency, that's his problem, not yours.
 

zz0468

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If some other operator gets his shorts in a wad because you're using digital on what he feels should be an analog frequency, that's his problem, not yours.

That's not going to fly...

In most areas, there are designated FM simplex frequencies. Digital modes are getting popular enough that the local groups that do frequency planning and coordination should be making suitable frequencies available for the various digital modes.

Good amateur practice would include making an effort to operate with local standards in mind. Popping up on a digital mode in the middle of a bunch of FM activity is not only NOT the other guy's problem, it could be interpreted as against the rules:

97.101 General standards.
(a) In all respects not specifically covered by FCC Rules each amateur station must be operated in accordance with good engineering and good amateur practice.

Learn what the local frequency assignments are, and find a place that fits in. It's really not that difficult.
 

human8472

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Thanks for all the answers. I will look to see if I can find a local band plan. I just want to stay within the FCC regulations and not annoy anyone else.
 

k6cpo

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That's not going to fly...

In most areas, there are designated FM simplex frequencies. Digital modes are getting popular enough that the local groups that do frequency planning and coordination should be making suitable frequencies available for the various digital modes.

Good amateur practice would include making an effort to operate with local standards in mind. Popping up on a digital mode in the middle of a bunch of FM activity is not only NOT the other guy's problem, it could be interpreted as against the rules:

97.101 General standards.
(a) In all respects not specifically covered by FCC Rules each amateur station must be operated in accordance with good engineering and good amateur practice.

Learn what the local frequency assignments are, and find a place that fits in. It's really not that difficult.

The Coordinating groups and the league need to get with it then and start designating spots for digital voice on the VHF/UHF bands. The only thing I can find looking at the band plans put forth by the two coordinating bodies in Southern California are slots for packet. Nothing for simplex modes such as DMR and System Fusion.

My club uses a 2 meter simplex frequency we chose ages ago for simplex nets and we aren't adverse to using it for System Fusion on occasion. Nobody seems to mind.
 

KD2FIQ

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I would love to see established calling frequencies for all the digital modes (C4FM especially). Sometimes I feel someone just needs to pick it and then maybe it will spread. Looks like Dstar and DMR have it figured out.

Sent from my SM-N910V using Tapatalk
 

I_am_Alpha1

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Human8472: Congrats on your Tech ticket. I truly hope you enjoy ham radio and advance to Extra. It can be tough as you see from the comments already posted as most of them are full of opinion and not fact--hams are very opinionated and stubborn. You will need to filter out what the law actually says. Refer to the actual FCC laws to verify what you are being told (even what I'm typing).

As to your original question: 28.3-28.5 SSB, 50.1-54.0, 144.1-148.0, 222.0-225.0, 422.0-450.0, 902.0-928.0, 1,240.0-1,300.0, and much more higher frequencies are legally available for you to choose at your will. Keep in mind that the upper and bottom limits will vary based on your bandwidth. There are some specific geographic restrictions you should be familiar with--like the "A" line or 70cm power limit in FL.

No one can tell you not to transmit on a specific frequency--they can however tell you that you can't use their equipment (meaning a repeater or echolink node needs a tone if they want to make it private as no one owns the rights to a frequency). You may not interfere with other users--basically don't talk while someone is using a frequency. All frequencies are used on a sharing basis--even repeater frequencies. You may transmit simplex on a repeater input frequency without using a tone and the repeater users are required to share the frequency with you.

The ARRL is nothing but a lobbying group. They do not have any authority or law enforcement powers what so ever. At the HQ level they do good, lobbying for the hobby. At the state and local level it's another thing where it goes to their head (some of them) and they believe they are law enforcement or policy makers--NOT! Frequency coordinators only help space out repeaters so they don't interfere with each other, but that is voluntary--no one is required to coordinate a repeater. I can install a repeater on 145.0 without coordination and no one can do a thing about it.

By law, I can talk on any frequency that my license allows. I can place a repeater on any frequency that my license allows and even tell you that you can't use it by using a tone. Personally I use 423-424 for simplex because I'm not near the "A" line and most people don't bother to "open up" their radios to TX on the lower part of 70cm. If you want a private frequency (actually doesn't exist) try 223.0 as that band gets very little use.

Now that we've covered that, let's talk about how things work. Band plans were created to help control the chaos. Many consider it good operator practice to follow the plan as best you can to help keep frequencies civilized. Uncoordinated repeaters are frowned upon--especially when there are so many seldom used repeaters available. A good practice would be to listen, listen, listen--this will help you learn how it is where you operate to help you better fit in. Visit some clubs to get the lay of the airwaves--there are good and bad clubs (my experience is that their are more bad clubs than good, which is very sad). You won't keep everyone happy, but stick to the band plan as close as you can and stand up for your right to use the frequency.
 
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hill

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PL tones aren't really to make the repeaters closed, but cut down on interference. Anyone that has a radio or scanner can find most PL tones quickly.
 

popnokick

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You may transmit simplex on a repeater input frequency without using a tone and the repeater users are required to share the frequency with you.
[snip]
I can install a repeater on 145.0 without coordination and no one can do a thing about it.
This FCC regulation could be applicable (note subpart (c) below regarding non-coordinated repeaters) -
§ 97.205 Repeater station.
(a) Any amateur station licensed to a holder of a Technician, General, Advanced or Amateur Extra Class operator license may be a repeater. A holder of a Technician, General, Advanced or Amateur Extra Class operator license may be the control operator of a repeater, subject to the privileges of the class of operator license held.

(b) A repeater may receive and retransmit only on the 10 m and shorter wavelength frequency bands except the 28.0-29.5 MHz, 50.0-51.0 MHz, 144.0-144.5 MHz, 145.5-146.0 MHz, 222.00-222.15 MHz, 431.0-433.0 Mhz, and 435.0-438.0 Mhz segments.

(c) Where the transmissions of a repeater cause harmful interference to another repeater, the two station licensees are equally and fully responsible for resolving the interference unless the operation of one station is recommended by a frequency coordinator and the operation of the other station is not. In that case, the licensee of the non-coordinated repeater has primary responsibility to resolve the interference.
 
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