All Questions

Filter by
Sorted by
Tagged with
10
votes
1answer
865 views

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. ...
11
votes
2answers
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 ...
4
votes
2answers
334 views

AX.25 to Kenwood $PKWDWPL sentence

In my vehicle, I have a Byonics TinyTrac4 paired with an AvMap G6. I also have a Kenwood TM-D710 that I'm currently using for voice. I live in a region of the US where both 2m APRS and 70cm High Speed ...
3
votes
1answer
179 views

Does using a computer SMPS to supply a transceiver bleed hum into the signal?

A dedicated/custom power-supply for an HF rig may, on occasion, be unavailable. The internet lists any number of articles on the subject of modifying a computer power-supply. E.g. http://www.wikihow....
12
votes
6answers
20k views

Calculating Antenna Length on the FCC Exam vs. in Reality

I have seen the following formulas for calculating half and quarter wavelength antennas: Formula for $\frac{1}{2}$-wavelength antenna (in free space): \begin{equation} \mathrm{Length~(feet)} = \frac{...
3
votes
2answers
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?
2
votes
0answers
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, ...
14
votes
2answers
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?
6
votes
1answer
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 ...
2
votes
1answer
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 ...
10
votes
2answers
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 ...
5
votes
4answers
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 ...
1
vote
2answers
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 ...
10
votes
2answers
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 ...
8
votes
2answers
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 ...
3
votes
0answers
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: ...
8
votes
2answers
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 ...
3
votes
1answer
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 ...
21
votes
13answers
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?
14
votes
4answers
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 ...
7
votes
2answers
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 ...
2
votes
1answer
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. ...
10
votes
3answers
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 ...
8
votes
2answers
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 ...
4
votes
1answer
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 ...
12
votes
1answer
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?
3
votes
1answer
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?
9
votes
3answers
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 ...
5
votes
1answer
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 ...
2
votes
3answers
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?
-1
votes
2answers
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.?
9
votes
5answers
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?
5
votes
1answer
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?
17
votes
8answers
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?
0
votes
1answer
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?
5
votes
2answers
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?
5
votes
1answer
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?
13
votes
3answers
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?
5
votes
2answers
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?
5
votes
3answers
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?
57
votes
16answers
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?
2
votes
5answers
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?
7
votes
1answer
1k views

Power limit of 50 ohm BNC connector?

Is there a limit to the power a 50 ohm BNC connector can handle?
3
votes
2answers
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?
8
votes
2answers
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?
4
votes
3answers
6k views

How and why sunspots affect propagation in HF bands?

How and why do sunspots affect propagation in HF bands?
2
votes
3answers
2k views

GNU/Linux contest logging software? [closed]

What contest logging software exists for the GNU/Linux operating system?
5
votes
2answers
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.
9
votes
4answers
3k views

Can I operate in the United Kingdom with a US license?

Can my license from the United States be used to operate while I'm in the United Kingdom?
16
votes
5answers
3k views

Can a licensed ham use or modify CB equipment to work the 10 Meter Amateur bands?

Can a licensed ham use or modify CB equipment to work the 10 Meter Amateur bands? If so, are there any advantages/disadvantages to this?

15 30 50 per page