Amateur Radio Stack Exchange
Amateur Radio Stack Exchange

Questions tagged [70cm-band]

Use this tag for questions relating specifically to the amateur radio UHF allocation around 430 MHz.

18 questions
37
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
  • 923
  • 1
  • 8
  • 19
11
votes
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
  • 211
  • 3
  • 7
8
votes
1 answer

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?
Jacob
  • 442
  • 3
  • 11
7
votes
4 answers

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?
Jacob
  • 442
  • 3
  • 11
5
votes
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
  • 4,262
  • 12
  • 48
4
votes
2 answers

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 70 cm band to the radiolocation service. Some of…
Rodrigo Magalhães
  • 71
  • 5
4
votes
3 answers

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 geography where you cannot use all or part of the 70cm…
Stephen Michael Kellat
  • 194
  • 2
  • 10
3
votes
3 answers

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.
Definity
  • 163
  • 5
3
votes
1 answer

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 more will be enough. Should I: Buy an…
KP4MCG
  • 217
  • 3
  • 5
3
votes
1 answer

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 the 70cm band, relative to its performance on the…
Andrew N5ITM
  • 923
  • 1
  • 8
  • 19
3
votes
2 answers

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 more than a thousand feet up in a pass, with a…
Zeiss Ikon
  • 4,055
  • 10
  • 31
2
votes
1 answer

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? Stereotypically the 2m VHF frequencies are considered to…
natevw - AF7TB
  • 7,219
  • 2
  • 23
  • 58
2
votes
1 answer

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 assembly is connected to the ground of the BNC.…
AndrejaKo
  • 2,853
  • 2
  • 17
  • 31
2
votes
1 answer

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.
W8AWT
  • 1,286
  • 1
  • 13
  • 32
1
vote
1 answer

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 need any other type of RF filters or will a…
vraho10
  • 11
  • 2
1
2