Dan KD2EE
  • Member for 8 years, 3 months
  • Last seen more than 7 years ago
Is Morse code allowed on FM in the USA
Accepted answer
17 votes

Completely legal. In fact, it's common practice to identify repeaters (both in the amateur service and in public safety/commercial) with exactly this method. That said, you likely won't make many ...

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Can a licensed ham use or modify CB equipment to work the 10 Meter Amateur bands?
16 votes

You can, but you probably don't want to. CB radios are limited to a set of 40 channels, most don't have frequency control. That somewhat limits the utility in the ham band where we have a very wide ...

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When may a ham operate beyond the privileges of their licence class?
14 votes

In the US, any person may operate under the direct supervision of an operator of a higher class. This is how the GOTA (get-on-the-air) stations work at field day, but it's applicable at any time. In ...

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Good wire for wire antenna?
14 votes

Because of the skin effect, which causes most of the electric current to be concentrated around the outer surface of the wire at high frequencies, larger gauge wire is needed for RF than for an ...

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Does iron ore in the ground affect my signal?
12 votes

If anything, living in an area with high metal deposits near to the ground will improve your conditions by improving the conductivity of your ground. That said, unless it's very near to the surface ...

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What does TX/RX Exchange refer to?
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10 votes

It's intended for contest logging. Most contests require that you "exchange" some information. Sometimes it's as simple as an RST signal report and you'd just enter whatever signal report you gave an ...

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Can I operate in the United Kingdom with a US license?
10 votes

Yes, with some extra paperwork. ARRL has most of the rules for international operating. In the case of a US operator in the UK, you'd be operating under CEPT. You'd need to be an Extra - General ...

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Why do concurrent FM signals not mix together?
Accepted answer
9 votes

I understand why you think it should mix - that's what happens with SSB, for example. The difference with FM is that in FM, at any instant, each station's signal is only at one frequency. If you ...

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How do I discover APRS coverage?
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9 votes

Coverage maps are a thing that is notoriously difficult to do right. There are some very complex programs (Radio Mobile is the one I know the most about) which can generate coverage maps if you're ...

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Is a Technician license enough to assist in times of emergency?
9 votes

Most local emergency communications use VHF and UHF repeaters. If we're talking about coordinating CERT or public safety, search and rescue, that sort of thing, then yes, a technician is enough. On ...

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2m or 70cm FM mobile radio for digital mode operation
8 votes

Sure, most radios have the ability to patch in audio. If it isn't through the front microphone connector, it's through an accessory connector, which is available on every commercial radio I'm aware of ...

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Abilities to limit antenna use?
8 votes

The only power that an HOA holds is that which is specified in the contract signed by the homeowner. This may limit towers or visible antennas. Hams have found quite a few ways around this: It is ...

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What are the most common RF connectors encountered in amateur radio?
7 votes

Connector use varies based on frequency band and also based slightly on power. The most common that I see, I have bolded, and while they are sorted by band, a VHF/UHF connector can be used on HF - it ...

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Can antennas have reverse harmonics
7 votes

The answer is yes (sort of), but it isn't because of "reverse harmonics". That doesn't actually mean anything. Quarter-wave antennas work for the same reasons as dipoles do - due to the physics of ...

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What causes ground losses in a HF antenna system?
7 votes

While ground effects are common concerns in almost every antenna and radio system, they are particularly important in the case of a monopole antenna. Monopole antennas, including quarter wave ...

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What is generally considered "too much" power for JT-65 on HF?
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7 votes

5 watts is probably what most JT-65 purists will tell you to use, but in practice, I tend to aim for 20 watts. That gives you a good 6dB boost (every doubling of power is equal to +3dB) which is ...

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Should I chose a vertical or a horizontal HF antenna?
7 votes

It doesn't really matter. You're asking about a topic called polarization, which is really important in VHF and UHF. It's the reason why rotating your HT can improve or harm your reception, and it's ...

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What organizations in the USA can I join to participate in emergency preparedness?
7 votes

The level to which amateur radio operators participate in emergency management varies between municipalities. ARES is the most well known organization, it is managed by emergency managers in each ARRL ...

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What type of solder is best suited for radio and electronic use?
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6 votes

First of all, acid-core solder is never used for electronics any more, that just isn't what it's for. I think it's still used for plumbing or other soldering where there aren't sensitive components ...

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75 watts and a mag mount antenna
6 votes

It's hard to make guesses about this sort of thing because there are too many different factors. The mag mount antenna certainly is better than your FT60 antenna, and the 75 watts is certainly better ...

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With solid-state equipment, when would one use a dummy load?
Accepted answer
6 votes

Any time you don't want to transmit RF. For example, if you have an oscilloscope and spectrum analyzer and would like to test the output of your transmitter (e.g. to make sure it's on frequency, that ...

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How do I power my radio in a vehicle mobile install?
Accepted answer
6 votes

While many transceivers and scanners can be powered by a cigarette lighter adapter, you typically want to run at most one transceiver in this way, and should make absolutely certain that you know ...

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Using more than 400W in the UK
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6 votes

This is not commonplace. Most operators in the UK get along fine with the 400W limit. Given the path losses inherent in Earth-Moon-Earth - hundreds of decibels - the antenna is a much more important ...

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Are there any antennas I shouldn't use in my car?
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5 votes

There's nothing particularly wrong with them. Cars, being mostly made of metal, do a pretty good job of shielding any RF signals, which is why you probably get worse reception when your HT is in your ...

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Power dissipation in transmission lines?
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5 votes

No. The cause of power loss in a feed line is not due to the characteristic impedance, it actually varies among transmission lines of the same impedance. Otherwise all 50 ohm coax would be the same - ...

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How do club codes stay secret?
5 votes

They stay secret because it takes a certain amount of effort and time to decode them - at the very least you need to record the tones and then feed them into a computer program. That means you need to ...

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How do I determine antenna spacing?
5 votes

If the antennas are at least one wavelength apart, you could use the Friis transmission equation. This would allow you to determine, based on the power of the transmitter and the antenna gains, the ...

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How would I go about setting up my own repeater in the UK?
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5 votes

Repeaters take time and money to set up and maintain. Many repeaters are operated by a club or a group - you may want to consider pooling resources with other local hams. Unlike in the US, UK amateur ...

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Power limit of 50 ohm BNC connector?
4 votes

Note that the following may not apply to adapters, which may have lower power limits. This thread on eham contains a few suggestions. The third poster states that the design rating is 7 amps on the ...

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Does modulation affect propagation?
4 votes

Usually, the answer is no. While modulation may affect the acceptable Signal to Noise ratio, allowing a given signal to be received from further away or in worse conditions than a different modulation,...

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