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67 views

Ufer ground and ground rods

I am about to build a new house with a ham shack incorporated in it. I am considering installing number 4 copper wire in the foundation around the perimeter as my ground ring. Is it necessary to ...
75 views

Selecting Directional Coupler for VSWR Measurement

Assume directional coupler is coupling with 16dB attenuation when signal is traveling from input to output. And directivity is let's say 20dB. If I understand correctly, when the RF signal is ...
60 views

JS8: does a QSO over a relay counts as a valid QSO?

I'm playing with the new JS8 mode. One feature I find particularly interesting is an ability to relay messages using rigs of other OP's. Though I'm not sure whether such QSOs should count as valid ...
93 views

A set of utility lines, and above them some high voltage power lines, run almost directly over the backyard fence. Some radio antennas are situated so that they can't fall onto the utility or power ...
125 views

What does CI-V stand for?

In the context of controlling a radio from a computer, what does CI-V stand for? I've noticed in relationship to a jack as well as USB. For example, from the Icom IC-7300 manual:
177 views

Antenna options for a 10x20m property with a large metal roof?

I live in a house that sits in the middle of the city, in a lot 10x20m in size. The first 6x10m are covered by a metal roof with a rather low angle (IIRC only 50cm difference between the highest and ...
71 views

How can I improve my Es'Hail 2 reception?

I'm using an RTL-SDR to receive Es'Hail 2. My chain is as follows in order: 60 cm TV Satellite dish pointing 2 degrees off Es'Hail 2 Universal LNB (from TV company, not really a stable frequency). ...
147 views

How does keying a CW transmitter work?

In my handbook it talks about keying the transmitter to produce the dots and dashes. Does this mean that the operator is turning the transmitter on and off, or does this mean that the key is turning ...
59 views

Really Low SWR Reading On PMR

I spoke to a friend about what antennas I was using for PMR and the frequency range on them was only set to 170-430Mhz he said it could lead to a high SWR, So I decided to test it out for safety ...
161 views

What dielectric strength is required for a variable capacitors in a 100W T-network antenna tuner?

I would like to build a 100W T-network antenna tuner: I have a 12-pole wafer switch, 12.5 meters of enameled copper wire (d=1.5mm) and a pair of 12-365pF variable capacitors rated 200V DC (dielectric ...
71 views

RG-213 Cable with electric strained wire as metallic shield of Coaxial cable

I'm using RG-213 coaxial cable for two-way ham radio communication. But due to weather conditions, the metallic shield of my coaxial cable (RG-213) become rusty and carbonated. If I use copper ...
53 views

Daisy Chaining AM filters to help with IMD

I live near an AM transmitter, and the input of my RTL-SDR becomes overloaded. I've added an AM filter and it's really helped, however I still get a very strong AM signal with some IMD all over ...
117 views

If I send periodic SOS and nothing else, what would be the response by hams and/or government?

TL;DR: If I blast out a periodic SOS, what rescue action should I expect? Similar to if I activated an EPIRB, or something less? This question is inspired by If I receive an SOS signal, what is the ...
77 views

Tips for HF Antenna with house near AM transmitter

My back garden is very small - about 500sqft. I also live near an AM transmitter and requires an AM filter. I would appreciate some general tips on the best approach to receiving HF signals (Ham and ...
295 views

Determining Impedance With An Antenna Analyzer

I need some help interpreting some information from my antenna analyzer (RigExpert AA-35). I want to use the information to impedance match my AM receiving antenna system to AM radios. No ...
48 views

UK “Remote Operation” defination

I am a UK licensed Amateur Radio operator with an Intermediate License. I have a question surrounding the UK's (Ofcom's) definition of "Remote Operation". My understanding is that for any Remote ...
106 views

Why does SDR# sound better than SDR console?

This is kind of odd. I just got my first SDR receiver and I noticed that one application (SDR#) sounds a lot better than another (SDR Console) when listening to stereo FM broadcasts through the same ...
252 views

What does QSL mean in a CW conversation?

When the other party sends QSL, do they just want to know whether I received the previous message and expect RR or ...
104 views

Where does this common spurious transmission come from? Is there a quality difference?

I decided to see what my ham transmissions look like on an SDR and was kind of shocked to see how much leaks out. The waterfall display is split between two handhelds during transmit. There are a ...
110 views

How do I identify a genuine Nagoya antenna?

I recently purchased a Nagoya NA-771 that I believe is counterfeit given the overall feel of the antenna. How do I identify a genuine Nagoya antenna vs. a counterfeit?
403 views

RigExpert AA-35 - Interpreting The Information

I have a new RigExpert AA-35 antenna analyzer. 1st one I have had & 1st time trying to use an analyzer on an antenna. My questions are very basic and general, but I am having difficulty in ...
77 views

I'm putting in a radial system for my inverted-L and am wondering if the hobby wire like the kind sold at Hobby Lobby or Home Depot for hanging pictures, which is 22-24 gauge copper or aluminum, would ...
307 views

Call sign ID for a “homebrew” or improvised repeater?

I saw a couple YouTube videos last night about setting up a repeater using a pair of cheap hand-held radios and, at its simplest, an audio patch cable to connect the speaker output of one radio to the ...
114 views

Cell tower identifier antenna isolator cannon

There are several cell towers on the hills around me. Usually I just walk around their base in a circle with one of the many CellID apps to get their ID. Then I can impress my friends, "That's tower ...
96 views

Line of sight from geographic/map data?

I have line of sight issues with repeaters I want/need to use (it's a repeater network my club uses). One of the options that might be available to me is to install a "passive repeater" in a location ...
95 views

Is there a trick for reaching a repeater “through” terrain?

I live in a draw, well below local average ground level. There are two repeaters I want to be able to use (because they're in the network my club uses). One is in the 440 band, thirty miles away but ...
96 views

Can I measure position with antenna/receiver?

I hope this question is not out of bounds. I'm a EE with little RF and you guys seem to know a LOT about RF... I have a small vehicle traveling in a straight line at low speed. I need to know when it ...
177 views

Is it safe to run two barefoot rigs on one antenna with an AB switch?

I have a Daiwa CS-201A two position switch. The single side is connected to by quarter wave vertical (40m). The A and B sides are connected to an IC-7300 and TS-830S. The switch is claimed to have ...
49 views

How to limit frame transfer in Gnu Radio Companion?

I have as source a bit frame, then I modulate it, to finally transmit it with my HackRF. I can receive and decode it normally with another HackRF. However I would like to limit to a number of frame ...
231 views

Bow Tie antennas impedance

I see on the internet that a radio amateur made bowtie antennas for transmitting and receiving on the 2 meter and 10 meter bands. They produced very good SWR bandwidth when fed with 50-$\Omega$ coax. ...
82 views

cubical quad reflector tuning stub design

I am currently building a two element portative cubical quad with one reflector and one driven element. the conductors of the driven element and reflector are encased in pvc tubing. I was wondering ...
72 views

Problem recording morse with sdr#

I have a problem with recording SWS-morse using SDRSharp and RTL-SDR. I want fixed gain, not audio automatic gain control. The problem is that all signal but the weakest will cause the recorded audio ...
533 views

RTL-SDR - rtl_fm: undefined symbol: rtlsdr_set_bias_tee

On a Raspberry Pi 3 B+ running Raspbian Stretch, when I run this command, timeout 115 rtl_fm -d 0 -g 49 -M usb -s 32000 -r 32000 -F 1 -f 50.293M outfile.raw I ...
192 views

What are the official Baofeng websites in the USA?

Which Baofeng website(s) in the USA is (are) official (that is, selling genuine Baofeng radios, programming cables, and accessories)? Which "Baofeng" websites are NOT, allegedly selling counterfeit ...
105 views

Will I get cleaner keying by keying the oscillator, or interrupting the amplifier B+?

One of my goals as a new ham is to homebrew my own transmitter (using vacuum tubes, aka valves). Initially I'll stick with CW for the transmitter, though over time I might build an AM modulator or ...
153 views

RTL-SDR dongle - what antenna should I use for APRS receive only?

I was following this guide to setup an iGate using an RTL-SDR dongle and a Raspberry Pi. It worked, and I have been able to test it by seeing some APRS packets from a separate transmitter (Arduino+...
126 views

Is there an 8-Watt “Upgraded” Baofeng UV-82?

I recently purchased a Baofeng UV-82 from a seller that advertised it as an "...Upgrade 8W". There are a fair number of these on Ali Express. Assuming it was a UV-82HP and the seller got the listing ...
111 views

How can I be sure I'm actually hitting the repeater?

I'm just starting to use 2m and 70cm bands, which normally use repeaters to extend range beyond a mile or two (limited mostly by line of sight, as I understand it). When I'm at home, however, I'm not ...
309 views

Brand new BaoFeng BF-F8HP — how to save settings in a channel memory?

I just got this new 2m/70cm hand-held, and I'm working through programming the local repeaters into channels. I've been able to set the repeater frequency in VFO mode, then save the settings to ...
106 views

How do I set the “tone” in my new BaoFeng BF-F8HP?

I just got this new 2m/70cm hand-held, my first ham rig. I neglected to order the computer connection cable with the radio (it's on the way, and I've already installed the Chirp software on my Linux ...
110 views

What is the radiation pattern of an EH antenna?

I haven't been able to find NEC cards or pictures of radiations patterns. I'm used to seeing them as polar diagrams, however, the only description I've gotten is "[t]he modification of the loop ...
193 views

How does lowering the RF Gain help with SNR?

Let's say for sake of example we are in the 40m band. I've read articles and posts about riding the RF gain (or even just simply lowering it). And I can see how it is useful in overload situations. ...
62 views

How to log contacts when mobile?

I'm just about to get on the air for the first time as a ham. It's been my understanding that it's good to log contacts with call sign, frequency, signal quality, and time of contact. However, for ...
121 views

Safeguards against cross-border abuse?

I live in a country that falls under ITU region three and recently joined my national amateur radio association. I learned that the frequencies for the repeaters run by the association were kept ...
120 views

Why does adding 50-ohm BNC Ethernet terminator(s) in parallel to my 4-element yagi improve my radio's reception? (70cm)

I have this radio, with a rubber duck antenna, and a repeater twenty miles away to my north-northwest. If I set my radio on the top of a cabinet in my bathroom, I receive the repeater fine. I can't ...
541 views

PL-259/SO-239 vs N Type vs BNC which is best connector to use when?

I understand that the: PL-259/SO-239 connector (so-called "UHF connector") isn't great for UHF frequencies, but is very common N type connector is water-proof; and the BNC connector is quick to ...
105 views

How can the gain of an antenna be negative?

Aaronia released this ultra-wide-range antenna, that can measure up to 35GHz. This was really impressive for only 3000 Euros, so I was considering purchasing it, when I figured I would look at the ...
74 views

Is the NATO/ICAO or ITU figure pronunciation more common?

I know the NATO/ICAO pronunciation of modifying 3, 4, 5, and 9 to "tree", "fower", "fife", and "niner", respectively, but I just discovered the ITU figure pronunciations are vastly different. Which ...