Questions tagged [vhf]

Very High Frequency is the frequency range 30-300 MHz.

Filter by
Sorted by
Tagged with
20
votes
1answer
4k views

Why do people say, “get a nickel,” on repeaters?

Sometimes, I'll hear someone say "wait a moment, I'm getting a nickel," and then drop the carrier only to resume talking. Why?
3
votes
2answers
159 views

What is proper procedure for asking for “distant” contacts on 2m FM on simplex?

As a new ham, just for fun, I'm planning to hike up to the local high point (which while not high in an absolute sense does have a commanding view of the surroundings) with my 5 watt FT-4XR and a slim ...
3
votes
1answer
48 views

Is it possible to convert a euro Yaesu 991a to US band plan?

I bought a euro Yaesu 991a . The vhf/uhf band plan is severely limited for use in the US . I have tried the button presses as shown for the earlier 991 and the service mode works to open the frequency ...
2
votes
6answers
1k views

Optimal length of HT antenna for VHF UHF and diminishing return

I see folding antennas of various lengths that people are using for for their HT. My question is about the optimal length. I know it may "depend" on many factors so let me know if I need to provide ...
4
votes
3answers
290 views

Is the Boom Strictly Necessary in a Vertical Dipole?

I'm planning to build a vertical dipole for 4m and a club member pointed out that my design needs to allow for a boom that should be at least a 1/4 wave long. Why does a vertical dipole need a boom ...
4
votes
3answers
280 views

Is testing SWR *practically* less important for 2m/70cm than HF bands?

Totally new amateur operator and I've noticed that a lot of material e.g. Your Tube videos, blogs, forums when discussing metering VSWR mainkly seem to be talking about HF bands. I also see fewer VSWR ...
1
vote
2answers
144 views

Trying to identify and understand this antenna design - ground independent dual band vertical

This is the insides of a common dual band antenna 2m/70cm, made by diamond or nagoya. its generally labelled as: 1/2 wave radialless (144MHz), 2 x 5/8 wave radialless (430MHz) Its meant to be ground ...
2
votes
0answers
55 views

Biconical antennas - bandwidth and installation

I am posting this question (and its related question) here because of the unique expertise that Ham Radio Operators have as it relates to antennas. I'm a newish Ham and really appreciate your help ...
3
votes
2answers
117 views

Why am I receiving a local tv channel on a CMB frequency

I am using a simple Baofeng H6 dual band radio and I programmed weather channels. Well, on frequency 161.77500 I am actually picking up WGN, a local tv network. This frequency should be reserved to ...
3
votes
4answers
9k views

Looking for a UHF / VHF transceiver for PC.`

I am looking for a simple UHF / VHF transceiver that I can plug into my PC via USB and be able to RX/TX on one channel, using the built in mic... Maybe even record the RX from the freq. Everything I ...
14
votes
4answers
11k views

Where are the baluns for VHF and higher? How can one be made?

In another question, commenters recommended that I look into adding a 1:1 balun to a dual-band dipole to eliminate the feedline as a radiator. As I understand it, a 1:1 balun also functions as a choke,...
3
votes
3answers
250 views

Use (TV?) Log-Periodic antenna for VHF

I found this old log periodic antenna that I assume was from a TV. Could I, or how would I, use this on the amateur radio bands? My main focus would be VHF, with UHF being secondary and HF would also ...
1
vote
1answer
83 views

What length and number of radials should be used for a dual band vertical whip backpack antenna?

The Situation: Very new Ham I have a 2m/70cm 48" Abree whip antenna, originally designed to be connected directly to an HT I would like to mount this antenna to the side of my hiking backpack, ...
13
votes
8answers
22k views

Is packet radio possible on Baofeng UV-5R and similar HTs?

I am curious to know if it is possible to do packet radio on VHF/UHF using the UV-5R... I have seen some invasive hardware hacks, but without modifying the radio itself (firmware, hardware) it's my ...
0
votes
1answer
41 views

Hatch Mount Antenna Selection - Dual Band 2m/70cm

I just bought a Diamond CP-5NMO hatch/lip mount and intend to put it on the hatchback lip of our 2018 Subaru Forester and, if it will fit, another one on our 2019 Kia Niro EV. I understand that hatch ...
4
votes
2answers
197 views

Heat-shrink as dielectric for bazooka balun?

I'm intending to make a sleeve balun (aka bazooka) for 2m, but rather than keep the lossy coax jacket as a dielectric (I have some RG58), was considering to remove it and replace it with heat shrink ...
3
votes
1answer
107 views

How to simulate two antennas in 4nec2

I need to simulate 2 helix antennae placed side by side, and see the resultant radiation pattern. But after adding the second antenna with a separate and when I try to simulate 4nec2, only simulated ...
12
votes
2answers
4k views

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 ...
3
votes
3answers
511 views

Ground-Plane radial sizing, is there such thing as too long?

I'm just trying to make sure I understand the theory correctly. I have some triband VHF/UHF/800MHz antennas, I need to mount on a tower so I plan on using a "mobile to base" conversion kit. ...
2
votes
3answers
151 views

Weakly directive VHF/UHF antenna

Most resources around the Internet discuss common antenna types, classifying them between directive (like Yagi) and nondirective (like a simple dipole). Directive antennas are good when you know from ...
6
votes
4answers
763 views

Any reason not to choose a discone antenna over a Wide/ MultiBand mobile antenna for TX/RX operations

We are setting up a all-band radio in an emergency com center that's intended most for amateur band use, but since its' for emergency use will also be used in the public safety bands; (150-170)MHz, (...
2
votes
1answer
772 views

how does this collinear antenna work?

I was looking for a cheap and easy to build 2M/70cm vertical. I found this: http://vk2zoi.com/articles/dual-band-high-gain-flower-pot/ Here are the plans to build it: But I don't really understand ...
1
vote
1answer
95 views

Handheld multiband radio for a ham firefighter?

I live half a mile from my volunteer fire station. We are toned out on a VHF frequency by a neighboring municipality, and we provide mutual aid for their fire department that is toned out on an 800-...
5
votes
4answers
455 views

Will Icom HM-133 work on IC-2800H

I have been having problems with the knock off of Icom microphone so I figured I would bite the bullet and get a new Icom microphone, since the original is out of production. I found that HM-133 looks ...
5
votes
2answers
663 views

Troposcatter: really all that bad?

The previous question, Packet Radio at 100 miles and specifically, Phil's answer raised an interesting question: In a 50–100 km distance situation where Line-Of-Sight beams aren't an option for ...
5
votes
2answers
313 views

Wide band TX capable band-pass filter for VHF and Airband

I want to share the same antenna for VHF (TX/RX 144-148 MHz) and for Airband RX-only (116-136 MHz). I live on a very congested area where filter is a must, so I'm looking for the best solution for my ...
1
vote
0answers
153 views

Extremely strong QRM on VHF?

I don't usually operate in 2 m, save for FM satellites. I usually go to a nearby park when I do this, for better view of the horizon. But I tried working them from home for the past couple of days, ...
2
votes
1answer
146 views

144/430 MHz antenna on 155 MHz?

We have a local radio shop that started selling us Relm P150s with a high gain 9 inch antenna, and those are ok. He also has thrown in longer 15 to 14 inch dual band antennas saying use those in ...
0
votes
1answer
103 views

How should I stack these folded dipoles?

Looking to stack these 8 folded dipoles on my 100ft tower. I can not find any information whatsoever on these. I have 4 consecutive serial numbered boxes. Bluewave Marathon BME139FN1H0 138 - ...
3
votes
5answers
377 views

Malicious interference to repeater

Our local repeater is severely sabotaged by unknown parties. For example, broadcast radio transmissions are repeated. Other times someone will send a transmission, when a qso is in progress. Local ...
3
votes
2answers
239 views

What VHF & UHF frequencies are important during an emergency?

If something bad goes down (state-wide or nationwide), what frequencies should I be tuning into? I did see this answer, but I have a BaoFeng UV-82HP which cannot do HF at all, so what are my options? ...
5
votes
2answers
328 views

BAOFENG UV-5R for cubesat communication on lab, does it work?

Here we have a cubesat which operates in VHF/UHF. Communication with it (from a ground station perspective) is done with an Icom Radio. Would it be possible to replace it with a cheaper BAOFENG?
2
votes
3answers
562 views

High Altitude Balloon Antenna Design

I'm designing a weather balloon with a club at college. We want to build the antenna from scratch to learn more about antennas but are at a loss as to which antenna design would actually work for high ...
1
vote
5answers
2k views

Can I contact the International Space Station using my Baofeng UV5R?

I saw this article but I can't imagine the power output, (eight watts max) would be enough to be picked up by the ISS at 200 miles above me. Similarly, I don't know if the preamp on the receiver ...
1
vote
1answer
84 views

Are there any satellite email reflectors?

I'm just getting started using amateur satellites and would like to subscribe to an email reflector, but I can't find one. Is there anything out there?
4
votes
2answers
65 views

2 meter Mode Options

FM seems to be the most popular in the 144 to 148 MHz Amateur Band .Narrow band is used for spectrum conservation . SSB is also used but is more common on the HF bands .Would SSB provide any ...
0
votes
2answers
57 views

Local Relay with static

On our local Relay there are from time to time transmissions, where only static can be heard. Most transmissions via relay can be heard clearly. What could be the cause of this?
4
votes
1answer
184 views

Does a UHF/VHF handheld transceiver kit exist?

I am a licensed ham looking for a UHF/VHF handheld transceiver kit. Unfortunately so far I was only able to find broken links, i.e. Ten-Tec used to produce exactly such a thing but they just don't ...
1
vote
3answers
676 views

Why aren’t emergency services using callsigns?

I’m super new to radio with nobody I know knowing it, so noob alert - plus some extraneous details in case you can comment on any of those. I got a pair of BaoFeng BF-F8HP radios with recommended ...
3
votes
2answers
2k views

What makes JT65 preferable for VHF, and JT9 for HF

Are the bands really that different in characteristics where JT65 works better for VHF, and JT9 for HF? The claim comes from the WSJT website: JT65 was designed for EME (“moonbounce”) on the VHF/...
3
votes
2answers
591 views

Noticeable difference between trunk and roof mount?

Between trunk-mounting and roof-mounting a 2m/70cm antenna, both as through-hole NMO mounts, is there really that big a difference performance-wise? I mean, I know roof mounting is better, but let's ...
3
votes
2answers
384 views

House wiring as an antenna on HF and 2 meters?

The apartment I live in is a 1970s type without access to the outdoors. It does have a balcony. A 2m transceiver is the only radio which will enable me to reach the ham world. Would be possible to ...
2
votes
3answers
857 views

VHF 50 Ω Antenna Over 75 Ω TV Coax

I have a 50 Ω VHF airband antenna which I’m planning to install in my loft, for use with a RaspberryPi-based RTLSDR scanner/receiver. I already have a UK-standard UHF/Freeview antenna using standard ...
1
vote
0answers
38 views

Unsure how to assemble Shakespeare SSB antenna; not working [closed]

Have 23 foot Shakespeare SSB antenna. Can not connect through the side feed termination band? Antenna not working? What is the band supposed to look like? Is the termination band supposed to be ...
5
votes
1answer
577 views

Kenwood TH-D72A: what's the difference between Tone and CTCSS?

Kenwood TH-D72A supports 3 types of tone: Tone, CTCSS and DCS. What is the difference between Tone and CTCSS? As far as I know CTCSS is basically a continuous transmission of a given low frequency ...
1
vote
1answer
275 views

Colinear Vhf antenna

Textbook colinear vertical antenna designs show coax cable with alternating braid to centre configuration. Commercial whips seem to utilise a single wire as the radiating element with .66 velocity ...
9
votes
2answers
2k views

Marine VHF whip antennae - what are they?

For marine VHF (156~162 MHz), the most commonly used antenna is a 1/2-wave dipole or a collinear array in the form of a fibreglass rod. Collinear arrays are used to increase gain in some antennas. ...
2
votes
2answers
916 views

Is there a DV VHF calling frequency in the UK?

On the band plan for VHF for the UK, I can see 145.500MHz being the FM calling frequency but I cannot find any for DV. Is there one? In contrast, for UHF, I can see a calling frequency for FM at 433....
27
votes
11answers
31k views

What's a cost-effective way to boost the range of my cheap 2m/70cm handheld?

I'm a very casual/beginner level ham and as such have mostly avoided committing too much in the way of financial resources - I have a UV-5R for a personal radio, anything else I do I've used others' ...
2
votes
4answers
7k views

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 ...