Questions tagged [70cm-band]
Use this tag for questions relating specifically to the amateur radio UHF allocation around 430 MHz.
20 questions
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Does sporadic E apply to UHF?
ES season is coming up so I want to know if ES applies to UHF. Google says that it applies to 6 meters and 2 meters. What about 70 centimeters? Can I talk further with 8 watts? They say you can DX and ...
- 805
2
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2
answers
157
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Performance of 2M/440 Amateur magnet mount antenna with CB
As I suspect that most people reading know already that a "well behaved" CB antenna tends to be quite large. In the past I compromised on a "proper" antenna to reduce size by ...
- 369
0
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1
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Maximum occupied bandwidth and symbol rate for amateur satellites [closed]
I'm looking for information regarding allowed occupied bandwidth and maximum symbol rate for the following amateur satellite bands
Amateur VHF (144 to 148 MHz) aka 2m-band
Amateur UHF (430 to 440 MHz)...
3
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1
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Recomended coax for 100ft (2m/70cm)
I recently moved to another house. My setup's current coax is 50ft/RG8x/PL259 (bought in 2018), but it is not enough for connecting my antenna to where I want to place the radio. I believe that 50ft ...
- 217
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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+...
3
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2
answers
478
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Is there a trick for reaching a repeater "through" terrain?
I live in a draw, well below local average ground level. There are two repeaters I want to be able to use (because they're in the network my club uses). One is in the 440 band, thirty miles away but ...
- 4,145
0
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2
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361
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Proper magnetic mount placement on roof
I have a Nissan Versa 2012 (hatchback). It comes with one of those default antennas at the back/center of the roof, for listening to AM/FM radio stations.
I have a dual band mag-mount (TRAM 1185), ...
- 217
2
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1
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1k
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440 MHz repeater, how would I set one up?
I’m currently attempting to set up my first 440 MHz machine.
From all the research I’ve done I need two radios, a controller and a duplexer.
I was going to go with a DR-1x. Is this correct? Would I ...
- 21
2
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1
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1k
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Dual-band rubber duck gain on 2m vs. 70cm
Using a dual band "rubber duck" like the stock Baofeng antenna and/or the physically longer NA-771, which band will give the best results between two mountain tops given the same input power?
...
- 7,469
4
votes
2
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536
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Experiences on a 70 cm band shared with radiolocation service
I currently live in Brazil and our governmental regulatory agency (www.anatel.gov.br) has recently started a public consultation process regarding the allocation, in secondary nature, of part of the ...
2
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1
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Is it possible to determine if I'm adjusting gamma match in correct direction with an SWR meter and if yes, how?
I've recently obtained a Quad Loop antenna for 2 m and 70 cm that's fed through gamma match, as shown in the picture:
The shorter metal bars are connected to the hot side of the BNC, while the longer ...
- 2,942
3
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3
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1k
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Website for satellite down/uplink frequencies and live footprint?
I am looking for a website that has the satellite footprint as well as the downlink freq. I just got a 2m/70cm handheld and want to see what I can pick up.
- 163
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6
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3k
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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 ...
2
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1
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2k
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Radiation pattern for a 1/4th wave 2 meter antenna used on 70cm
What would the radiation pattern look like if I used a 1/4th wave 2 meter mag-mount antenna on 70cm with an HT.
- 1,346
4
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3
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What are the geographical restrictions in using the 70cm band in the United States of America?
Geographical restrictions exist for various frequencies in terms of usage in the United States of America as stipulated in 47 CFR 97.303. What are the restrictions, if any remain, in terms of ...
3
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1
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What is the theoretical performance of a 2m 1/4 wave ground plane antenna when used at 70cm?
If I have a 2-meter 1/4 wave ground plane antenna with 1/4 wave radials bent down at approximately 45 degrees, what kind of performance in terms of SWR and gain pattern can I expect when using it on ...
- 943
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2
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What is the essential gear to have in a VHF/UHF FM base station? [closed]
I'm trying to assemble a VHF/UHF FM base-station at home. Assuming I have the following pieces of equipment:
VHF/UHF FM transceiver
power supply - 30 amps, no meters
antenna that's resonant on 2m and ...
- 943
38
votes
4
answers
46k
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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....
- 943
7
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4
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4k
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Why is the 70cm band commonly referred to as the 432MHz band?
I keep reading and hearing the 70cm band (420-450 MHz depending on local regulation) referred to as the 432 MHz band, particularly by older hams. Why?
- 442
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1
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473
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Why do USA transceivers limit transmit to 430-450MHz?
The FCC table of frequency allocations clearly states on page 27 that the Amateur allocation for 70cm is 420-450MHz, but I've seen a lot of transceivers that limit transmit to 430-450MHz.
Why is this?...
- 442