# All Questions

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### Can I have multiple inverted-vee antenna fed by a single coax?

A friend who recently received his call is planning to setup an inverted-vee for 40/20m bands. Our take is the signal will take the path of least impedance into the correct length antenna wire. ...
567 views

### Why is an exemption for music given to NASA broadcasts of manned space flight missions?

FCC 97.113 Prohibited transmissions reads: (e) No station shall retransmit programs or signals emanating from any type of radio station other than an amateur station, except propagation and ...
334 views

3k views

### How to calculate the peak-to-peak voltage of a sine wave given RMS voltage

How do I calculate the peak-to-peak voltage of a sine wave given RMS voltage?
74 views

### When and how do I use a Smith chart? [closed]

What are some real-world problems that a Smith chart can help me solve? Ultimately I'd like to gain a more intuitive understanding of the space the chart represents, but it seems to me that actual, ...
915 views

### Why is the solar-flux index measured at 10.7 cm?

Why is the solar-flux index measured at 10.7 cm? What makes that such a special frequency?
7k views

### How to find the front-to-back ratio given an antenna radiation pattern diagram?

I know that the front-to-back ratio is 18dB in the below antenna radiation pattern diagram, but I don't know how to read the diagram to obtain this result. How does one read and understand such ...
113 views

### Model of a specific DVB-T tuner chip (circa 2013) that can be used to collect raw IQ samples

There is a common DVB-T receiver chip capable of producing raw IQ samples, which makes it a good device for Amateur Radio SDR experimentation. The chips is used in some DVB-T USB dongles sold around ...
972 views

### Where can I find the official definition of ITU Zones?

I've been looking around for a spot that has the official definition of what the various ITU Zones are, but can't find one. What is the official definition? I'm hoping for more than just a map, unless ...
3k views

### Can I listen to hams on a standard AM/FM broadcast receiver?

I am very much out of practice with amateur radio (like many others), so to some, this question may seem obvious. I don't have any specialised amateur radio equipment, but I do have a Sanyo AM/FM ...
56 views

### What are some fun activities hams participate in? [closed]

Yes, Amateur radio is a hobby. The general impression however is that it is a geeky/nerdy/kooky (I forget which carries a negative connotation!) hobby; either the ham sits at a transceiver, or is ...
240 views

### Which qualities/features does an SDR radio device need to be usable for Amateur Radio?

I know what things to note when selecting an analog amateur radio, but SDR devices have completely different specs, e.g. sample rate and resolution. What do I need to know about the device to make ...
5k views

### Phasing harness for antenna array

I understand that certain antenna designs (particularly phased arrays) require feeding each radiating element with a certain number of degrees of phase separation in order to achieve a desired ...
381 views

### Getting Started with APRS [closed]

The APRS.org web site provides some good information but is not very well organized and does not appear to be actively maintained. What are some good resources for beginners seeking the following: ...
136 views

### How is ARES different from RACES?

Just what the title states. Here, in India, in the context of public service we hear of RACES (Radio Amateur Civil Emergency Service). I recently learnt about something called ARES in a similar ...
301 views

### How is a “Generally Inactive” ham determined for Field Day GOTA?

ARRL Field Day Rules allow a GOTA station to be operated by "a generally inactive licensee. " There are members of my club which started to become active again after a long term of inactivity a few ...
15k views

### How can one convert from Lat/Long to Grid Square?

I see that many contests, awards, and other items, use Grid Squares as a means to identify where one is. How can one figure out what one's grid square is, given lat/long?
2k views

### OK to use any repeater?

There are a number of repeaters in my area, each belonging to a particular amateur radio club. These guys are all friendly and willing to chat but I was wondering if it was bad form to make use of a ...
1k views

### Practical 80m vertical wire antennas without radials?

We'd like to install an antenna for 80m at our club/contest station. Our club, OH2K, is housed at a school, and we can't fill the roof with a radial mesh. The roof is not metallic itself, either. We ...
107 views

### Interference generated by antenna placement?

I'm thinking about putting up a 80m dipole in the back yard, the only place I have to put this (can't do inverted V since I don't have a high enough location) is close to a overhead telephone wire. ...
560 views

### How to Evaluate Antenna Data

I found some data on antennas that had been tested for a specific radio. I'm trying to decipher what this data means and how one would go about gathering it. Are there any good resource for learning ...
135 views

### What regulatory issues/differences should I be aware of as a US ham vacationing in Europe (Poland)?

I am a US ham with an Extra Class ticket. If I were to go Poland (or possibly some other part of Europe) on vacation and bring some radios, what legal stuff do I need to know about? I know that my ...
92 views

### HSMM problems introduced by mismatched antenna feed points

I have been trying to understand the finer points of HSMM, and I ran across this statement about antenna feed points (emphasis mine): 802.11 signals produce very broadband signals, typically 20-22 ...
16k views

### What do “QRM” and “QSB” refer to?

An answer on Basic QSO format? mentions things like "QRM" and "QSB". What do those terms mean?
1k views

### Is there a way to modify my Yaesu FT-60 to transmit on all 4 ham bands it can receive?

I have a Yaesu FT-60, and it can transmit on 2m, 70cm, and receive 1.25m and 33cm bands. I would really like to find a way to get it to transmit on 1.25 and 33cm. Is there a way to make this happen?
1k views

### AIS and RTL-SDR Dongles

I am looking for an Windows-based AIS Decoder for RTL Dongles. Currently, there is a solution available using GNU Radio and SDR# but it is complicated to set up and keep running. ADSB has a dedicated ...
373 views

### Secure communication over Amateur-band HSMM / 802.11 in the United States

I'm quite interested in 802.11 over amateur radio frequencies; however, all I have done at this point is reading (I don't have a ham license yet). The conventional wisdom (espoused in this ham.SE ...
419 views

### What's the purpose of a soundcard in digital communication?

If I get involved in digital communications do I need to buy a soundcard? If so, why, what does it do?
1k views

### Basic QSO format? [closed]

What is the basic format for a QSO? How should I answer to "CQ", how do I know when it is my turn to answer, when should I give the report, etc.?
385 views

### Is a Technician license enough to assist in times of emergency?

Is a Technician license enough to assist in times of disaster/emergency or do I need General or higher?
211 views

### Can I modify my radio to transmit on frequencies that I can currently only listen to? [closed]

I bought a radio that can receive 4 ham bands, but only transmit on 2. Can I modify my radio to transmit on these frequencies legally?
24k views

### Should I chose a vertical or a horizontal HF antenna?

If I only have the budget for one HF antenna, should I chose a vertical or a horizontal antenna?
94 views

### Can wood be used to build 6m quad? [closed]

Could I use wood to build 6m quad? If not, what material(s) would be better/more useful?
2k views

### Pros/cons of the PL259/SO239 connector (M type)?

What are the pros/cons of the PL259/SO239 connector (M type), and why is it used preferentially on civilian rigs vs military?
317 views

### How do I determine antenna spacing?

How do I determine antenna spacing so that I don't end up overdriving the front end of a receiver when transmitting?
33k views

### Good wire for wire antenna?

What properties should I look for in a good wire for building a wire antenna? Could anyone recommend something specific for me?
116 views

### Abilities to limit antenna use?

What kinds of abilities does a Home Owners' Association (HOA) in the United States have to limit the use of antennas placed on a roof to an owner of a home in the area?
3k views

### What frequencies am I not allowed to use north of line A in the USA?

What frequencies can I not use if I live north of line A in the USA?
7k views

### Why is Morse Code still in use?

Why do people still use Morse Code? What are its advantages over newer Voice or Data communication modes?
463 views

### Metal for antenna construction?

What do I need to consider when choosing metal for an antenna? How do I determine what thickness to use?
1k views

### Power limit of 50 ohm BNC connector?

Is there a limit to the power a 50 ohm BNC connector can handle?
8k views

### Antennas I can effectively use in an apartment? [closed]

What are some antenna designs that balance manageable size/shape with effectiveness for use in an apartment?
754 views

### Vertical antenna on HF?

What are some of the advantages and disadvantages of using a vertical antenna on high frequency? Are there any better antenna types that I should use?
6k views

### How and why sunspots affect propagation in HF bands?

How and why do sunspots affect propagation in HF bands?
2k views

### GNU/Linux contest logging software? [closed]

What contest logging software exists for the GNU/Linux operating system?
1k views

### Battery capacity vs. weight for portable transceivers

What kind of battery has the most capacity for the weight? I want to take my transceiver backpacking, so I care about weight.