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advice needed for balanced line terminals

I am designing a portable antenna with a radiating element and a balun that are not close to each other. the impedance has been designed to be close to 50 ohms. So i will feed the antenna with a ...
0
votes
0answers
10 views

House wiring as an antenna on HF and 2 meters?

The apartment I live in is a 1970s type without access to the outdoors. It does have a balcony. A 2m transceiver is the only radio which will enable me to reach the ham world. Would be possible to ...
1
vote
0answers
11 views

How do I design a dual band LPDA antenna?

Im not sure if this is the best place to ask a question like this but its the best place i could find. My goal is to build a dual band antenna similar to this one. https://www.telcoantennas.com.au/...
2
votes
1answer
46 views

Frequency Display for Old Tube Radio

I have a Hallicrafters S-120 1960s vintage vacuum tube receiver (an "All American Five" superhet with solid state rectifier replacing one of the "five" tubes). It works well, doesn't have excessive ...
0
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0answers
26 views

How to control flowgraph variables from a Webserver? [on hold]

I have a simple "dial tone" GRC application that I am running through a simple python webserver, when I run this application and call the freq method I have to set the variable value before running ...
-1
votes
1answer
31 views

TypeError: 'float' object is not callable [on hold]

I am getting this error TypeError: 'float' object is not callable when trying to call the methods into my web server: This is my error log: ...
2
votes
0answers
28 views

What's the issue with stainless steel antenna elements? [duplicate]

New ham, here...getting motivated to build some antennas to experiment with and so far my research has shown that stainless steel is not a desirable metal for creating antenna elements - which is a ...
1
vote
1answer
30 views

Can I connect a 75 ohm antenna to a 50 ohm radio?

I have been looking for an affordable yagi antenna to use with a dual band handheld radio and I came across some very inexpensive VHF/UHF (HDTV) antennas. They are all 75 ohm though. Is it ok to use a ...
1
vote
2answers
70 views

Audio being sent over ground pin on audio jack

I just bought a QYT KT-8900D mobile radio. One of the first things I've noticed is that I cannot use my mixer to completely lower the volume of the radio's 3.5mm TRRS output. When the fader is all the ...
3
votes
1answer
61 views

What type of antenna is this?

I have very little knowledge about antennas (I just read about simple dipoles and monopoles recently) and I need to buy a directional antenna for my wireless device. I have found a cheap antenna (I ...
5
votes
2answers
650 views

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 ...
4
votes
1answer
41 views

Relative computational requirement for various digital modes?

What might be the relative computational performance requirements for the various popular digital modes? (FT, JT, WS, PSK31, etc.) I seem to recall FSK modulation/demodulation being done with 1 or so ...
2
votes
1answer
28 views

Propagation Analysis with WSPR / RBN

I would like to analyze data from the Weak Signal Propagation Reporter (WSPR) and/or the Reverse Beacon Network to understand the propagation mode(s) of the recent welcome spate of CW and SSB contacts ...
0
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0answers
46 views

No module named 'analog_swig' [duplicate]

I know guys you gonna tell me tat there is something wrong about GnuRadio or Pybombs installation. Well, this is my third time during the past 48 hours I reformat the OS of my mini pc fitlet2 mint ...
2
votes
1answer
88 views

Can I capture stereo IQ signals from WebSDR?

When I set my sound device to record from the monitor/loopback source, I can capture the signal from WebSDR in my browser in an application like Audacity. Looking at the captured signal more closely ...
3
votes
0answers
69 views

Where did the LP to BP transformation $ \frac{\omega ^{2}-\omega_0^{2}}{\omega\cdot BW} $ come from?

I'm not sure this question is appropriate for this site, but I feel that if anyone knows about a filter, a radio ham knows! And as a ham myself I feel I need to understand this important area better. ...
4
votes
2answers
64 views

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 ...
2
votes
1answer
39 views

SDR as an oscilloscope

Can a SDR be used as a general purpose AC oscilloscope with appropriate attenuation at the front end. Have in mind a capacitor to block DC voltages, large resistor say 10 Mohms to limit current and ...
1
vote
3answers
87 views

Is it possible to have multiple people talking on the same radio channel at the same time?

I understand that my question is not desireable for ham radio communication at all, but bear with me. I want to use long range walkie talkies whose microphone is attached to an underground acoustic ...
5
votes
1answer
83 views

How does a Faraday cage block an EMP?

If you search the Internet for Faraday cages, you'll find a lot of information about using homemade cages to protect radios from EMP damage while in storage. A lot of that information is either ...
0
votes
0answers
36 views

No module named _osmosdr_swig [duplicate]

I am trying to run GnuRadio python code in my python web server and got the "No module named _osmosdr_swig" error. Please, what is the cause for this error? I know it sounds like so obvious that I ...
1
vote
0answers
47 views

Can my neighbors ham radio station be preventing my TV antenna from proper reception? [duplicate]

I have a winegard 8200 series antenna and it worked flawlessly in getting me reception of more than 70 stations. The wind blew it down and I couldn't replace it for about 6 months due to the fact that ...
2
votes
2answers
107 views

No module named 'gnuradio'

I encountered with the "No module named 'gnuradio'" error while I was trying to run GnuRadio python code in my python web server. And this is my gnuRadio generated code: ...
5
votes
1answer
66 views

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 ...
2
votes
1answer
88 views

Merging gnuradio generated python code into the Python web server

I am trying to figure out how I control a Software Defined Radio over a network, and stream the received baseband samples from my remote hardware back to the gnuradio. What I'm trying to do here is, ...
1
vote
2answers
179 views

Will transmitting on this antenna cause problems?

Inspired by this discussion, I wanted to check if this is something I can get away with. I've got an old FM Broadcast antenna that came with a home stereo receiver -- it's 75 ohm flat cable, in a T ...
4
votes
3answers
80 views

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 ...
2
votes
1answer
59 views

Presumably working FT-8900R doesn't turn on. What can be a reason?

I bought a pre-owned Yaesu FT-8900R. Sadly turned out that the radio doesn't turn on. When I hold the power button (the right bottom one) the speaker pops briefly but nothing else happening. The ...
1
vote
0answers
60 views

Simple Gnuradio TX/RX loopback example/tutorial

I'm looking for some sort of simple and a beginner level instructions on how to build TX/RX loopback flowgraph using GnuRadio software and B200 USRP with an attenuator FW -10 + 10dB. Kindly, help me ...
1
vote
0answers
22 views

Unsure how to assemble Shakespeare SSB antenna; not working [closed]

Have 23 foot Shakespeare SSB antenna. Can not connect through the side feed termination band? Antenna not working? What is the band supposed to look like? Is the termination band supposed to be ...
2
votes
3answers
706 views

VHF 50 Ω Antenna Over 75 Ω TV Coax

I have a 50 Ω VHF airband antenna which I’m planning to install in my loft, for use with a RaspberryPi-based RTLSDR scanner/receiver. I already have a UK-standard UHF/Freeview antenna using standard ...
3
votes
0answers
74 views

GnuRadio RF transmission, legal and safety issues

I'm trying to run some transmit/receive RF examples that I found online using GNU Radio with USRP B200. I read and heard about some cautions in terms of transmitted frequencies here in the USA which ...
3
votes
1answer
63 views

fan dipole with loading coil(s)?

There seem to be plenty of construction articles on center-fed wire fan dipoles with pairs of arms of different lengths, each pair dimensioned for a different band (e.g. half-wave 80M+40M+20M,etc.). ...
2
votes
2answers
738 views

What is this burst transmission sequence across the entire band?

Fairly regularly on the 40m band I hear a quick blip of a tone, and when I look at the waterfall I see these brief transmissions all across the band that look like little dots. What is causing that?
2
votes
1answer
38 views

Using EchoLink with Satellite delivered Internet

I am new to Echolink and I have Hughes Net Satellite delivered Internet service. Can I use Echolink with my Satellite service since there is a longer delay involved. Thanks in advance for your ...
1
vote
3answers
61 views

2m 5-element yagi with staggered driven elements

I have seen sketches of 3-element 2m yagi antennas in which the driven dipole elements are staggered i.e., one element is positioned slightly in front of the other along the length of the (plastic) ...
3
votes
1answer
210 views

How do amateur satellites stay consistently in the amateur-sat bands acoss the globe?

I understand that my local laws may differ but amateur radio satellites, by their very nature, orbit the earth going over several legal jurisdictions. Are satellite bands the same internationally? If ...
1
vote
1answer
60 views

Radio antenna for my FM receiver / Android FM

I want to make a radio antenna at home which will be able to receive all FM frequencies for my FM radio or Android FM. How do I make it? Frequency it can catch : 88 - 108 MHz Thanks.
1
vote
0answers
18 views

FLDigi Crashes When Trying to Load RigCAT Description File

I am trying to setup FLDigi with my ICOM-7300 via the USB connection so I can start using digital modes. Everytime I try to follow the instructions here, it doesn't work. Specifically, everytime I try ...
1
vote
1answer
24 views

Power output of KT8900

Any ideas on adjusting the low power output of the KT8900. The output tranny has a max rating of 12V and specs are centred on 7.5 volts. Yet they try to run it at 13.8V?? I want to reduce the output ...
2
votes
2answers
59 views

Orange Goop Leaking from Power Supply

I have a Baofeng UV-82 with the charging cradle and switching power supply (wall wart). Tonight, I noticed a slick spot on the floor next to the couch, and saw some orange goo on a paper I had picked ...
4
votes
1answer
73 views

Kenwood TH-D72A: what's the difference between Tone and CTCSS?

Kenwood TH-D72A supports 3 types of tone: Tone, CTCSS and DCS. What is the difference between Tone and CTCSS? As far as I know CTCSS is basically a continuous transmission of a given low frequency ...
8
votes
5answers
1k views

Will electrically joined dipoles of different lengths, at right angles, behave as a multiband antenna?

I haven't seen this done, (which, after more than a century of amateur and professional radio development, is probably a bad sign), but I had an idea the other day for simplifying the setup and feed ...
2
votes
0answers
42 views

HackRF One and IoT overloaded?

I'm transmitting Z-Wave frames using HackRF One in loop, one frame every second. Has anyone clue why are some frames not transmitted? You can see several too long gaps between frames on Waterfall (...
4
votes
1answer
80 views

Dipole symmetry?

In ideal free space, both arms of a tuned wire dipole will be of identical length. However, the real world is not perfectly symmetric free space. The support heights, ground levels, ground ...
2
votes
2answers
81 views

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 ...
1
vote
1answer
70 views

Simple antenna for LoRa 433 MHz module

I have some LoRa SX1278 433 MHz modules: However, I don't have an antenna. My question is: what would be a good antenna option for longest range? I don't really care that much about transfer speed, ...
1
vote
0answers
21 views

Baofeng 888s side key didn't work and solved [closed]

Thanks. Solved. Baofeng 888s, programmed with chirp, worked great. I hit the device with CHIRP many times, Everything was ok., but moni button after a month, didn't work. First I thought that the ...
4
votes
2answers
56 views

Propagation effects of noctilucent clouds

I know auroras are a propagation mode, but I was wondering with the recent outburst of noctilucent clouds (as reported on www.space.com) brings with it any interesting propagation modes, either on HF ...
2
votes
1answer
42 views

How do I interpret the FCC ground conductivity 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 ...

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