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1500 questions
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2 answers

Communications : Ground wave propagation

I was studying ground wave propagation, my book writes the lines about it without explaining it. I really do not know any explanation for these queries coming in my mind. I've Googled it, and you will get nothing so good for these queries on Ground…
Selena
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Variable phase antenna

I'm thinking about phased antenna arrays, and am wondering if it's possible to have three fixed position antennas, and vary the length of their individual feedlines to the common point through mechanical means. The best way to describe what I'm…
Adam Davis
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Are there any rules/conventions for transmitting coordinates in CW?

I am wondering how hams transmit coordinates in Morse code. Considering that coordinates can be represented in many different formats (such as DD, DDM, DMS, WGS84, etc.) and that an error in the decoding of the coordinates can mean a lot, it seems…
codeaviator
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calculating all specifics for a 5/8 antenna

So, I've built a couple 1/4λ ground plane antennas for Airband and Marine band. I don't transmit, I'm just listening, etc. So, constructing ground plane antennas with the radials and getting the impedance to be 50Ω is rather easy, not so for the…
polemon
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Has anyone actually heard or used rare Morse code characters on the air?

When I got my license about 50 years ago, I believe the only punctuation marks on the test were the period, comma, question mark, and slash mark. Once on the air, I heard and used the usual prosigns, [AR], [BT], [SK], [KN]. I also frequently heard…
Michael
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2 answers

Who should announce the call sign when an unlicensed operator is transmitting?

If an unlicensed operator is operating phone on an amateur frequency under the direct supervision of a licensed operator for, say, longer than ten minutes, should the unlicensed operator say the call sign of the licensed operator, or should the…
Noji
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How to get professional or official clarification of FCC Part 97 rules for specific complicated situations?

I'm specifically focusing this question on methods to get official clarification where one doesn't currently exist. I am not asking this audience for interpretations. As part of my volunteer work with CERT, we're exploring a number of communication…
Matthew Wetmore
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What is the point of a SWR/power meter where the needles cross over each other?

There are SWR/power meters with two separate gauges, and others that have them mounted so the gauge needles cross over each other. Aside from looking cool, does the cross-over point of the two meters provide specific or useful information?
Adam Davis
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Are ionospheric predictions useful in practice for ham radio operators?

A number of government agencies around the world provide ionospheric predictions, such as vertical foF2 or oblique path useable frequency range advice. Examples include IPS, SWPC and DIAS. Typically, the major customers of these agencies are in…
Bogdanovist
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How do I extend broken coaxial cable?

I have a piece of 75 ohm coaxial cable of unknown type (outer diameter is around 7 mm) which has developed a breakage in the center conductor (which is stranded). This cable is an adapter cable which connects my RG-6 type coaxial cable to my RTL-SDR…
AndrejaKo
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Use a TV coax and balun for a poor-man's OCFD?

Can I use TV coax and a cheap TV balun to build a poor-man's OCFD? Marginal performance is acceptable if it saves money. If I could listen to 10% of transmitters within a 100 mile radius that would be acceptable. And as for the coax length, probably…
SlowBro
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Simple cheap foxhunting?

I'm currently looking to do a foxhunt for a youth group, and need to keep it inexpensive and easy enough that it won't be impossible for those new to foxhunting and ham radio, but difficult enough that it will still be rewarding. I'm a relatively…
Adam Davis
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2 answers

Is it possible to overload APRS?

Does APRS have a limited capacity in terms of beacons? What happens when an APRS frequency experiences a large number of packets?
JC Hulce
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8
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2 answers

HF Digital Mode Band Plan for the USA

I recently started playing with the digital modes, but have been frustrated with the difficulty in finding where certain modes are commonly used. Is there a digital mode band plan for the HF bands, to the level of which modes are commonly used on…
PearsonArtPhoto
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4 answers

Two Antenna Tuners in Series

My radio has an internal antenna tuner that can be activated to rapidly tune for the frequency in use. My antenna has a disgusting SWR for the band I want to use (as measured with an AA-54 antenna analyzer). When activating the internal antenna…
Steve
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