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1500 questions
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3 answers

Cheap antenna for new HF HAM

I just got a 100W HF radio and I am new at this. What is the cheapest antenna I can hook up without burning up my radio or shocking myself?
Pugz
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ARRL handbook as a reference for all your radio learning needs?

Looking to take up learning understanding everything from basic electronics to how today's wideband radios work, so that I can build my own radio systems (not just ham radios), and talk radio concepts better. Would ARRL Handbook be a good enough…
eecs
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How is a crossed-ellipse display generated from FSK?

What is the algorithm or circuit needed to generate a (vintage?, retro?) crossed-ellipse display from RTTY and/or 2FSK signals? (as per the (obsolete?) questions in some FCC exam pool) (assume already down-converted from HF RF to either/or a…
hotpaw2
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Can I modify my radio to transmit on frequencies that I can currently only listen to?

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?
Timtech
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What does a receiver's noise reduction function do?

Some receivers contain a noise reduction button or function. What does this noise reduction do? Is there more than one type of noise reduction? How does the circuit or software know what part of the signal to reduce as noise and what part to not…
hotpaw2
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2 answers

Can anyone identify this military radio?

Hoping someone can identify the following military radio. I spotted it at the curb and decided to make it a land-fill diversion project...
radiorabid
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Why a capacitor is needed in Fuchs antenna?

I tried to understand the physics of Fuchs antenna and there is one thing that I don't quite understand. This is probably a very silly question, but I spent a lot of time looking for an answer (books, online) and didn't manage to find it. Modern…
Aleksander Alekseev - R2AUK
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6 answers

EFHW works only on one band - what am I missing?

I tried to build a multiband EFHW antenna as described in articles by PA3HHO, PD7MMA, G0KYA and many others. I decided to start with a short 40/20/(15?)/10 meters version without any loading coils. Surprisingly, no matter what I tried I didn't…
Aleksander Alekseev - R2AUK
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5
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3 answers

Heathkit SB-102 Plate Current out of control

I bought a "technician special" Heathkit SB-102 transceiver. Everything seems to work well until I attach a dummy load and try to go through the "initial tune up" procedure in the manual. At the point where I switch the "Mode" to "Tune", instead of…
Zeiss Ikon
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Why is my calculation for added length of coax for a double cross antenna different to everyone else's?

I'm an amateur amateur radio enthusiast finally building my own antenna, and have decided on a double cross antenna, with the goal of pulling data from NOAA satellites. Four coax cables, two of length x, and two of length x+λ/4. For 137 MHz, the…
zeph
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Better SWR bandwidth

Good day, I have a Kenwood TS-480HT with a Wolfriver coil and a stainless steel whip in my car. I find that on 40 meters I can get the SWR at around 1.4 (using an MFJ 269) at 7.1000 MHz. But the SWR goes high (2.5 to 3.0) very quickly if I go closer…
Danny
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How should two loopstick antennas be placed w.r.t each other to maximize transmission?

An engineer working in the RF industry told me something which left me very confused: He said that a pair of emitter-receiver beacons get the clearest signal when loopstick antennas in the receiver and the emitter are parallel. That is, when both…
Dugas
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3 answers

Why does no one use a Buddipole as an Inverted V?

I have been looking at the Buddipole, and I've seen the most popular configuration is as a standard dipole with the arms parallel to the ground. I've also seen it configured as an upright V, as well as configured in a sloped condition. But I haven't…
SandPiper
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Can I take and use Baofeng UV-82 in Norway?

Planning to go for a camping trip. According to this document (in Norwegian but easy to understand), I can use a radio running PMR446 and KDR 444 freqs. Baofeng can do this. The question is: is the Baofeng unit legal itself? And is it legal to take…
Alexander
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How do I interpret the FCC ground conductivity map files?

The FCC has .seq files that show ground conductivity which it makes available for download. Unfortunately, there doesn't appear to be any documentation that comes with the files, or even headers. I can make an educated guess that there are two…
user3486184
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