# All Questions

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784 views

### Closest antenna to an isotropic? [closed]

What is the closest antenna ever made to an isotropic antenna? That is, has the same gain in every direction in free space?
5k views

### Is it illegal to key up and not identify?

So, I key up on a repeater to see if it works, or to see what cool courtesy tone they are using. I don't do anything else. Is it illegal or bad ham radio etiquette to just key up for a second, key ...
932 views

### Bicycle mobile antenna

I have mounted mobile verticals (mag mounts) on my bicycle, but I have learnt that a bike does not have a good RF ground because there is nothing close to a plane. Without wasting too much more ...
302 views

### What rig or rigs are onboard the ISS?

This article mentions the Ham Shack aboard the ISS. From the picture it looks like a small very light rig like a Yaesu FT-817. What radio(s) do the astronauts use when they talk to Hams and School-age ...
503 views

### How to increase antenna aperture?

I know that in the short wavelength region, where parabolic antennas are used, the aperture can be increased simply by making the dish larger, as is the case with the radio telescopes. But how to do ...
323 views

### Energy vs power in transmitters

Higher frequencies have a higher energy, simply stated by Planck's constant. When I am transmitting 100 watts on 500 kHz, and transmitting 100 watts on 5 GHz, is there an energy difference in the wave?...
315 views

### 2 m meteor scatter FM voice freq?

What frequency should I use to try and make meteor scatter contacts on 2m FM tonight, with a nice meteor storm coming?
1k views

### Fastest Speed allowed for CW FM repeater ID in USA

What is the fastest legal WPM I can use for my repeater's Morse code identification? I am in the USA.
3k views

### Using Earth as an RF ground

I have built a simple ground plane antenna for 70cm with a connector, 4 radials, and one vertical element. The RF ground is connected to the radials, and the RF is connected to the vertical. It got ...
392 views

### Why is an RF ground not as critical as the other, and can they be used backwards?

I will give the magmount antenna as an example: The vertical element to the antenna is very critical, cut to a certain wavelength, often added with some loading coils, or a little spiral to make ...
613 views

### Consistency of Morse Code/CW sending speed

How important is it to maintain a consistent Morse Code WPM keying speed when transmitting CW? I occasionally hear operators slow way down when sending RST and location info, and then later ...
419 views

### Is it possible to radio between America and India?

My friend and I want to see if we can Ham radio between San Jose, CA and Bangalore, India. We're beginners and are going to be using handheld radios. Are there any networks of repeaters, that could ...
337 views

### How do you operate an “up 3” split dx station with a Kenwood TS570 or similar HF radio?

My Kenwood has "split" and "rit/xit". Is the "split" mode suitable for operating a split for a DX pileup situation, where a station is listening "3 up"? I'm confused about which of the larger or ...
343 views

### How to choose a coaxial cable

How do you know which coaxial cable to choose for your application? For instance; I require a cable that has a 50ohm impedance, an operating frequency of 2.4GHz, length of 100mm, and needs to be ...
5k views

### Baofeng uv-82 will not transmit in channel mode?

I have 2 Boafeng UV-82 radios. I programmed the frequencies using Chirp. When I try to access the repeaters in channel mode I cannot connect. When I switch to frequency mode and turn off the duplex ...
36k views

### What is a Gamma match in the context of the driven element of a Yagi antenna?

How (and why) does a Gamma match work, when used on the driven element of a Yagi antenna? As shown here: (source: http://www.iw5edi.com/ham-radio/?2-element-yagi-for-10-meters-band,49) The article ...
418 views

### Can two FM radios transmit two separate PL tones at the same time, and be received by two radios with matching PL tones?

Can two FM radios transmit two separate PL tones, and be received by two radios with matching PL tones? Or will the receivers hear a mix of the two, or nothing at all?
357 views

### Should the capacitance or inductance be varied to achieve resonance?

A resonant circuit is typically composed of some resistance and reactance, the latter being provided by inductors and capacitors. The resonant frequency being calculated as the inverse square of their ...
137 views

### Capacitance methods (antenna extensions, whole body as antenna) for receiving better

I have seen that there are times where reception isn't very good on a radio, but as soon as the hand is approached as much as possible to the antenna (with or without direct contact to the actual ...
12k views

### Spacing between elements on a Yagi antenna

Does anyone know what the spacing between elements on a beam antenna should be? I built a 146 MHz 3 element beam following instructions, and the spacing was 16" between the driven element and the ...