Questions tagged [vhf]
Very High Frequency is the frequency range 30-300 MHz.
161
questions
0
votes
0
answers
23
views
How does the rabbit ears antenna work?
How do I built a rabbit ears antenna?
I would like to know how a rabbit ears antenna work, like the one shown in the picture below.
From:
https://en.wikipedia.org/wiki/Television_antenna#/media/File:...
- 19
0
votes
1
answer
21
views
Questions about radio antennas
I need to know a few things about radio antennas.
As per the theory, the length of any antenna works best if it's length is exactly the same as the wavelength. With that said, if I need to build an ...
- 19
1
vote
4
answers
127
views
Gap between a dipole antenna
I need to know how much gap should be there between the two arms of a dipole antenna?
I would also like to know how much gap is there between the two rabbit ears antenna and is the loop antenna ...
- 19
0
votes
1
answer
145
views
Why are VHF bands closed all the time?
Why are the VHF bands closed every day? Is it getting abandoned? Every time I check the solar conditions, it says that the VHF bands are closed. GlobalNorth says, "As the big public safety and ...
- 594
4
votes
2
answers
146
views
Shifting Frequency of a VHF Crystal?
I have a boatload of 165.550 MHz Regency 10.7 MHz IF Crystals. I need them to resonate for 165.500 MHz. How can I shift the crystal frequency down 50 KHz without opening the 'tincan' and messing ...
- 59
1
vote
0
answers
92
views
TYT TH-350 unlocking to receive 160-161 MHz in the USA
Recently purchased the TYT TH-350 because it is triband. My version allows for TX/RX 144-148/222-225/420-450. Every other HT I own allows for extended
receive only. The TH-350 has a European version ...
- 131
-3
votes
1
answer
429
views
Handheld amateur radio
Recently purchased a MY-EMR1 which is a handheld ham radio and I want to synchronize it to my sisters in another state if it is possible, she has the same type of radio. All the frequencies have been ...
- 1
0
votes
2
answers
182
views
Using Aviation VHF radio on different frequencies
I have an old Icom A-5 aviation handheld with a frequency range of 118.000-136.975 MHz on top of WX, AM, and FM receive functions. Is there any way with little modification, or a simple static build ...
4
votes
0
answers
64
views
Optimizing Half-Duplex Sequencing: Consolidating RF and Power Connections with Bias-T and VOX
I've successfully implemented a half-duplex sequencing mechanism, which I've illustrated below. The outdoor components are represented in green. In my current setup, I utilize a PLC to control both an ...
2
votes
3
answers
672
views
Monopole antenna with no ground connection
I have a SDR device and have a question about using a monopole antenna with them, but the question could be applied to any device which uses an antenna.
SDR comes prepacked with a monopole antenna ...
- 311
1
vote
1
answer
113
views
Pulsing static on 6m
Located in Illinois, US, I recorded this http://loami-windmill.com/sounds/6m_noise.m4a on 28-June-2023 at 1603 UTC on 50.074MHz USB. The static has regular "pulses" where it gets slightly ...
- 949
1
vote
1
answer
239
views
Creating a single feed wearable wire antenna
When I was deployed, our commo guys gave us wire antennas we could thread through our body armor (through the MOLLE loops).
These antennas were just lengths of 50Ω coax that had the insulation ...
- 155
2
votes
1
answer
202
views
UnUn for VHF and UHF
Is it possible to build an UnUn for VHF or UHF like in HF?
Goal is to use a simple endfed wire or piece of metal as an antenna.
EDIT: I meant "endfed halfwave".
- 21
2
votes
2
answers
155
views
Is the noisy spectrum from 20MHz to 330 MHz normal?
I have recently been testing some VHF/UHF antennas for reception in my Lab, and have noted something I could not explain. Following are the spectrum plots captured on our R&S FSV spectrum analyzer,...
- 23
1
vote
1
answer
464
views
A new ham should start with Digital or Analog Portable Radio?
I am interested in acquiring two portable radios to talk between a family member and me (both new hams), e.g. when we go trekking in a National Park or to communicate in the same city. We used PRM ...
