11

The regulations for an amateur radio repeater are fairly minimal. To answer your specific questions: "Does one need a particular license?" Your license must permit transmissions on the repeater output frequency. That is, general or higher for 10m, technician or higher for higher frequency bands. There is no special repeater license. (There used to be.) ...


9

WA9ZZZ's answer missed the issue of control of the repeater. The repeater must be under control of one or more control operators, or under automatic control, at all times when the repeater is on. There are three types of control: Primary control, where a control operator is physically near the equipment and monitoring the repeater, ready to intervene as ...


9

There is a kind of repeater that can repeat any kind of transmission: it's called a linear translator. It's technically equivalent to an SSB receiver linked to an SSB transmitter. It works for any mode because SSB is simply a shift in frequency. Other than the change in frequency, the baseband and RF signals are linearly related. This is also why an SSB ...


8

I wouldn't assume that repeaters with the same call are connected. What the call sign denotes is that they're owned and operated by the same operator or club -- for instance, in my area, there are multiple repeaters on W4NC (Forsyth Amateur Radio Club), but calling through the one on Sauratown Mountain doesn't let you talk to someone tuned to the one on ...


8

It is presumed that you were receiving on the 2m band. It appears that you were listening in, using 'repeater reverse' mode. In other words, you were listening in on the repeater's input frequency rather than on it's output. On 'reverse', you would hear all the stations within range. In this case only one station would have been within range. Had you ...


6

Possible, yes. A good idea as your plan for emergency communication while hiking on a remote and hazardous trail? I wouldn't count on it. As you've already observed, although there are repeaters along the way, you have to know what they are, you have to be in range of them, and someone has to be listening. Consider the things that could go wrong: You ...


6

Talkaround: Transmitting and receiving on the repeater output frequency. Thus, you "talk around" the repeater directly with the other station. (Same as simplex). Both stations in a conversation can do this. Reverse: Switching transmit and receive frequencies. Thus, you can talk directly to another station that is still on the repeater's ...


4

A repeater simply listens on one frequency, and retransmits what it receives on another frequency. If one repeater happened to listen on the frequency another was transmitting, theoretically you could exploit this to extend your range in one direction at least. Unfortunately as a user you have no control over these frequencies. To avoid interference with ...


4

They often do set them up to link to various repeaters. PRA for example. If those repeaters are linked it may work. If not it would not. Are you in contact with the repeater owner?


4

"Carrier access" just means that you do not need a CTCSS tone to access the repeater. Your carrier brings up the repeater. CTCSS access may reduce co-channel interference between repeaters if their coverage area overlaps, but it is not technically necessary for access.


4

A repeater would be complicated, you'd need to get into the details of how the signal works. Fortunately 439 MHz is in or near the amateur band, so external antennas are available. I suggest you modify the receiving end of the system to include an external antenna. To double the range of a radio link, all things equal, you need an additional 6 dB of gain. At ...


4

This sounds like desense cycling: Repeater receiver detects signal. Controller keys transmitter. Signal from transmitter gets into receiver and blocks incoming signal. Controller decides input signal gone, unkeys transmitter. Transmitter off, receiver detects signal. Cycle repeats. Your duplexer might not be working as well as it should. Or possibly, you ...


3

It doesn't know anything. "STE" is the easier one to explain. It controls transmit, not receive. When STE is enabled, when you let go of the PTT button, the radio will send a 55Hz tone for a moment. Other Baofeng radios mute the receive when they hear a 55Hz tone... whether or not the STE option is enabled, whether or not you want it. It has no (...


3

Different frequencies and different locations ... many clubs operate multiple repeaters to give their members access in extended areas. They are NOT necessarily connected. MGRA (Middle GA) has several, two of them CAN be linked via EchoLink; but normally are not. The have the same club call sign.


3

The concept is called "offset". The repeater is listening on one frequency, and is repeating it verbatim in real time on another frequency, but typically at a higher power so more people can hear it further away. Most repeaters (numbers specific for the US anyway, but the concept applies internationally) have a plus or minus 600 khz offset. This is not a ...


3

Yes, your diagram makes sense. And yes, it's doable, given that your amp operates within the power limits of the duplexer and the antenna, and the duplexer isolates the receiver from enough of the amplifier's output. Every solid-state rig that outputs more than a watt has a power amp inside of it already, so it's not a question of "can it be done" ...


3

"E-power" is probably an abbreviation for "emergency power", meaning that the repeater is able to function (for some amount of time) even if grid power to the repeater site fails. A "link" is when two repeaters are connected (over radio, internet, or phone) so that they repeat transmissions heard by either repeater, thus having a larger coverage area or ...


2

I am guessing that you programmed a receive tone requirement. Try programming only the transmit tone and leaving the receive tone not required. I don't have Chirp available right now so I can't give you the names of these fields. Best, Ed Greenberg KM6CG


2

It is likely that you can operate the TK-890H at 100% duty with better cooling. This would be a lot less work than the scheme you propose. The Kenwood TK-890H has no fan - a good thing for mobile use, it's quiet and it will stay clean and last longer. But to keep it compact, the heatsink is much too small for continuous transmission. My reasoning: The radio ...


2

The transmitter doesn't need protection from the receiver, because the receiver doesn't transmit any signal. Indeed. The notch filter in the transmit side is instead to protect the receiver from the transmitter. As well as the familiar harmonics and spur signals generated on specific frequencies by the transmitter it also produces broadband noise centred on ...


1

Just adding to the previous answers. Many people, mostly preppers, throw a cheap Baofeng into their emergency kit or whatnot. Here's the problem with that: so many people have no idea how to use it. I'm almost done with my general license and I still have to use the internet o figure out how my new radios work. Not a bragging/insulting point, but rather ...


1

Sure, I suppose it's possible. Any sort of "voting" seems overcomplicated to me. Simply have a timer that switches to the next radio every 30 seconds or so. If you have five of these radios and switch between them periodically, no one will have a duty cycle above 20%. If you have less than 5 radios then reduce power. The complicated part I suppose ...


1

In an area with good cellular (mobile) phone service, then a cell phone is hands-down the best option for everyday emergency communications. However, many parts of the world, particularly rural and mountainous areas, have better coverage through ham radio repeaters than the mobile (cell) phone network. There are several reasons for this: A cell phone tower ...


1

The transmitter doesn't need protection from the receiver, because the receiver doesn't transmit any signal. Perhaps not, but consider: The transmitter makes broadband noise and intermodulation products that may fall on the receive frequency. More isolation is better. And, The transmitter should ideally also not load the antenna at the receive frequency. ...


1

the industrial, scientific, medical or ISM for region 2 (the Americas) is 902 to 928 MHz. Power is limited to no more than 1 watt without a license. Many consumer devices such as cordless phones use this band as well as industrial networks like ZIGBEE. Amateur radio operators in region 2 are secondary users of this band also know as the 33 CM band. While ...


1

Part of what makes a repeater valuable is it filters out "invalid" or weak signals. This makes them efficient in power use as it's not transmitting all the time. This makes them valuable to the users as they aren't hearing noise all the time through their radios. What makes the signal "valid" is having sufficient power, at the correct ...


1

I don't know any radio firmware that would support blocking a specific ID. It would be easy to implement in MMDMHost. Call Alert is a ringer function. If a radio receives a call alert signal then it rings and sends back an answer to the caller and the caller radio shows a message about the successful delivery.


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