Amateur Radio Stack Exchange
Amateur Radio Stack Exchange

Questions tagged [2m-band]

Use this tag for questions relating specifically to the amateur radio VHF allocation around 144 MHz.

56 questions
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votes
4 answers

What's the difference between national calling frequency and national simplex calling frequency in the 2m and 70cm band plans published by ARRL?

On the 2 meter and 70 centimeter band plans published by the ARRL, what is the difference in intended use between the calling frequencies (144.200, 432.10 MHz) and the simplex calling frequencies (146.52, 446.00 MHz)?
Andrew N5ITM
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13
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2 answers

Is there an optimum Antenna Feedline Length for mobile installations?

I bought a ham radio antenna mounting kit for my car that includes ~16' of coax. One end has a trunk lip NMO antenna mount, the other end has a re-solderable PL-259. I asked the sales person if it is best to shorten the coax after installation to…
BenSwayne
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11
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6 answers

While backpacking, is it worth mounting the antenna to the backpack frame (above my head)?

I am planning a trip with a large group in 6 weeks. We will be spread out in small groups on a trail in a mostly desert plateau landscape perhaps 5 miles apart, but mostly in a straight line. I'm new to amateur radio, but I have been studying and I…
NL - Apologize to Monica
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10
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2 answers

Getting Started with Digital Modes on VHF on Linux

I am interested in learning about digital modes using 2m and Linux. I have a couple of older 2m rigs (HTX-212 and an old Yaesu) with no additional hardware, like a TNC. What current resources exist for hardware setup and software configuration for…
Rob Gibson
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7
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5 answers

Is the National Calling Frequency actually used?

I know that the national calling frequency is 146.520. Everywhere I go, it does not give a DUP or TSQ. I am not trying to be or, ask a crazy question but is there or not.
Glenn
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6
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4 answers

What is the minimum signal strength I need to receive?

Let's say a transmitting station is using a 8W radio with a J pole antenna. The cable connecting the radio to the antenna is RG-58A/U and is 25ft long. At 144.075MHz, the attenuation of the cable is 1.5dB. At 8W, the power from the radio is 9.03dB.…
KM4NTK
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6
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1 answer

Two antennas on different sides of a building

I live in the 4th floor of a building with one side facing south and the other north. I am able to use my 2M mobile base transceiver with a mobile magnet mount antenna placed just outside the window. I get fairly decent coverage of areas on one side…
4G1BGS Larry
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5
votes
1 answer

HF/VHF antenna for high altitude balloon

I'm working on the design of a dual band transmitter for use on a high altitude balloon. I'll be transmitting on 2 meters and 20 meters (APRS and WSPR) with about 50 mW. To keep the weight to an absolute minimum, I'm designing it to use a single…
whalphen K8VFO
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5
votes
2 answers

How to adapt commercial VHF yagi for 2 meter amateur use?

I recently acquired a Decibel 3-element VHF Yagi that was formerly in commercial service. I connected my MFJ-259B antenna analyzer to the antenna and found its minimum SWR at 155 MHz. I have not measured the boom length or the element lengths. I'm…
Aurelia Peters
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5
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1 answer

bizzare CW on 2m

I'm currently in Kershaw, SC. Yesterday an automated signal popped up on a 2m simplex freq (147.455 MHz) and has been running since. It sounds like Morse, but it is random letters that don't seem to have any repeating pattern. After every seeming CW…
Aaron
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5
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2 answers

What gain and power are required for successful DX contacts on 2m/70cm bands in CW?

I would like to practice in CW on 2m/70cm bands when and if there will be a tropospheric or sporadic-E propagation. However I don't have mush space for the antenna. There is a possibility to install 3+5 el Uda-Yagi antenna on the balcony (the height…
Aleksander Alekseev - R2AUK
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5
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3 answers

Why are 2m and 70cm the common frequencies on HTs?

Why do most HTs have 2m and 70cm as the two bands? Is it just out of history or tradition, licensing restrictions, or is there something in the transceiver or antenna design that would make these the two obvious frequency bands of choice?
RoboKaren
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4
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6 answers

Slot antenna for 2 meter mobile

My primary vehicle is a Smart car, with a roof that's a piece of plastic(100% moon roof). Not the most awesome of cars to use for grounds. I'm building a bumper mounted antenna tower, EMT with some square tube. Earlier today I stumbled across an…
Omagasohe
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4
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2 answers

Ideal antenna type for FM 2 meters?

Clearly, building a Yagi tuned for 2 meters will likely have the best directional performance. Putting that aside, I'm trying to get information on what antenna type will have the best overall performance in the 2 meter band in an NFM mode. I have…
David Hoelzer
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3
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5 answers

If i connect two antennas to one radio using a t connector will it work?

If I connect two antennas to one radio using a t connector will it work? If a connect 2 antennas (a mag mount + a dipole?) to the same radio with an adapter will it work normally on 2M band and will it cause extra interference? Also, if it works…
Charl1110
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