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2
votes
1answer
25 views

Is this “floating” output single-ended or differential and against GND or VCC?

I'm looking at a simple FM transmitter output (see picture). It is from the collector of a transistor and it goes through a DC blocking capacitor before the antenna would be connected. The entire ...
0
votes
1answer
19 views

Increasing communication range by boosting output and input power

I am trying to increase the range of communication between two SDRs to simulate near space communication. The output power of TX is 10dBm but I would need 37dBm for near space communication. That ...
5
votes
2answers
153 views

Can half of a directional antenna (Yagi-Uda, HB9CV) be replaced by a ground plane?

Consider a center-fed dipole antenna. It‘s well understood how the bottom element can be replaced by a ground plane (in practice, generally a few rods but in principle a conducting plate would work as ...
2
votes
1answer
52 views

In Canada, does a person need to be licensed to buy amateur radio equipment?

I have studied for and am ready to take my amateur radio license test but there are currently no licensed instructors available in my region to administer the test. Can I start acquiring ham radio ...
0
votes
0answers
15 views

Hatch Mount Antenna Selection - Dual Band 2m/70cm

I just bought a Diamond CP-5NMO hatch/lip mount and intend to put it on the hatchback lip of our 2018 Subaru Forester and, if it will fit, another one on our 2019 Kia Niro EV. I understand that hatch ...
0
votes
1answer
20 views

Bidirectional motor control using MFJ-4116 with RCS-4

I have the RCS-4 with two MFJ-4116. Prior to installing my motorized HF antenna system topside, I bench-tested the core of the assembly in my shack. The MFJ-4116 near my transceiver was injected with ...
2
votes
1answer
51 views

Looking for criticisms on my VNA-like SWR meter I am designing

I am in the process of building a SWR meter with VNA-like features. I'd be really interested to hear from fellow hams any input, suggestions, or tips they have regarding this before I go get it mass ...
2
votes
1answer
78 views

Half wave dipole with parasitic element, (Gain calculation)

good morning all, I have difficulties to find the correct formula that allows me to calculate the gain of half wave dipole in parallel with another parasitic half wave dipole. I'm trying to calculate ...
4
votes
1answer
26 views

License document requirements

Are there any requirements to post, carry, or have available an official paper copy of one's radio license in order to operate in the U.S.? Do any states require physical possession of a printed ...
1
vote
3answers
57 views

Why is outer coax usually grounded?

I'm building a simple ground plane antenna for VHF, and I'm doing some research on grounding in case I want to permanently install it. I keep hearing that the ground rod is connected to the outer coax ...
3
votes
2answers
298 views

Recommendations for starting out with HF for an amateur

I'm a beginner who's nearly half a year from receiving my ham license in India. I want to start with HF radio and wish to build my own rig. Currently I have looked and multiple designs using the ...
1
vote
2answers
30 views

How do I find when my license expires?

I have a general license but I do not know when it expires, please help.
1
vote
0answers
13 views

Can the AT-D878UV be programmed for dPMR channels?

I am curious whether the Anytone AT-D878UV (which is a DMR radio) can be programmed to receive dPMR channels. I understand that the big difference between DMR and dPMR is the technique used to divide ...
1
vote
1answer
18 views

How to calculate of shielded loop antenna correction factor without extra antenna measurements

A lot of article about 60 cm shielded loop antennas and how to measure antenna factor using antennas with already known antenna factor. But for example if I have one shielded loop antenna (...
1
vote
1answer
34 views

Output power from the TX/RX port of the USRP N210 decreases as the frequency increases

I am trying to build an FMCW radar using a USRP N210 with a CBX40 daughterboard. I generate a sweep from 1.5GHz to 5GHz. According to their respective datasheets, the daughterboard and the USRP should ...
3
votes
2answers
42 views

Recommendation for hobbyist flight computer radio antenna

I'm a CS college student working on the flight computer of my Rocketry Club's rocket. My flight computer has a 915MHz radio transceiver, and it needs to transmit data to my computer with another radio ...
1
vote
1answer
15 views

What length and number of radials should be used for a dual band vertical whip backpack antenna?

The Situation: Very new Ham I have a 2m/70cm 48" Abree whip antenna, originally designed to be connected directly to an HT I would like to mount this antenna to the side of my hiking backpack, ...
1
vote
3answers
213 views

Why are no 2w FRS walkie talkies on the market?

I have read that the new laws regarding FRS radios state that you may use up to 2 watts power, yet I can't find a single 2 way radio that advertises 2 watts power; only .5 watt, or they don't state ...
0
votes
1answer
31 views

Ground pass through cinder block — copper pipe, braid, stranded?

What’s the best way to connect a station (desk) ground bus to an outside ground rod? Is it viable to double-sleeve a copper tube through existing PVC pipe? For coax pass thru, I have a 1.5” PVC pipe ...
1
vote
1answer
39 views

Repeater carrier as access

I'm just getting into ham radio. I'm trying to connect to a repeater here in Ireland: Channel: RU260(RB10) Output: 433.250 Input: 434.850 Call sign:EI7SHR Access: Carrier What does the "...
0
votes
1answer
354 views

Yaesu FT-817 Won't transmit on 160m to 6m

I'm having the following problem with my FT-817: 1) Receives fine on all bands 2) Transmits fine on 2m and 70cm 3) Doesn't transmit at all on 160m through to 6m 4) Keying the MIC on 160m to 6m, ...
0
votes
2answers
93 views

How do you know if you're on a 10 meter band?

I am just getting into ham radio, and I find it very interesting, but to make phone calls, you have to be on a 10 meter band. Does anyone know how to infer the band you're on is 10 meter? Thank you ...
1
vote
1answer
98 views

Repeater identification ending (CW)

I am just starting to learn CW, and for practice I have been recording and transcribing repeater identifications that I hear. This is what I heard today: DE W9KIC/R BBG What is the meaning of "BBG"?
5
votes
3answers
242 views

Getting Started In Ham Radio

I'm 13 years old. I hear all the fuss about ham radio how awesome it is. I really want to join, but I hear you have to get a certification. How much does it cost? How long does it take? How much does ...
2
votes
3answers
135 views

How can I get started with Amateur Radio?

I would love to get involved with amateur radio, but I'm not sure how. My community recreation center hosts a class to get a Technicians license for a reasonable price ($10), and I know a little bit ...
7
votes
3answers
6k views

Straight to General license, skipping Technician?

I would like to get involved in ham radio and I'm inclined to study for and take the General exam right away, rather than going for Technician and then upgrading. Are there good reasons not to do this?...
10
votes
4answers
947 views

What is the highest US amateur license I can get in one sitting?

If I start with no current license, can I take all the exams in one sitting to get to Amateur Extra?
6
votes
3answers
271 views

What does a first-time operator need to know when looking for a DIY kit?

When I was growing up, I lived about three blocks from a Heathkit, and envied every device on the shelves. Now that I'm older, am teaching myself electronics and have a background in film and ...
6
votes
7answers
150 views

Space Requirements

As I progress in my path to getting a ham license I notice that a lot of radio enthusiasts avidly talk about their radio shacks (or do they call it cabins?). Do I need that much space to start? Do I ...
3
votes
1answer
59 views

If WSPR can go further than FT8, why do I only see local WSPR signals?

I've been scanning through the bands using WSJT-X to pick up FT8 and WSPR. Using a VHF discone, I decode messages from nearly 10,000 km away, consistently, when listening for FT8. But when switching ...
1
vote
2answers
60 views

Benefits of AGC?

I note that many popular kit and QRP radios do not include any AGC capability. Thus it must be possible to operate successfully without AGC. Are there difficulties involved in manual gain control? ...
4
votes
5answers
5k views

Grounding a dipole

How do you properly ground a dipole (RX only for VHF scanning) to protect it against ESD/lightning? In my set up i'm putting a dipole on my roof. I've connected the two dipole elements together with ...
0
votes
1answer
65 views

Anyone know what this antenna is?

Hello, what kind of antenna is this? I’ve been trying to figure it out for 14 years. None of my neighbors know. Whomever installed it either moved or passed away.
4
votes
2answers
125 views

Heat-shrink as dielectric for bazooka balun?

I'm intending to make a sleeve balun (aka bazooka) for 2m, but rather than keep the lossy coax jacket as a dielectric (I have some RG58), was considering to remove it and replace it with heat shrink ...
1
vote
2answers
42 views

FT-450D not transmitting with microphone

I've been using FT8 on my Yaesu FT-450D for quite some time. I decided to try to talk on phone frequencies and discovered neither one of my mics will transmit. My mics are the original hand mic and a ...
1
vote
3answers
49 views

Where to find QRM and/or QRN audio files?

I'm looking for some QRN/M audio files to "show" someone what said noise can sound like, particularly interested in static crashes or lightening bursts. Have Googled same with no joy other ...
1
vote
1answer
35 views

Physical QSL card request procedures?

Is there a way to determine whether a station or operator still sends physical QSL cards, rather than only uploading some data online? (or doing nothing at all.) If so, what is the current procedure ...
2
votes
1answer
63 views

Is it possible to show frequency and channel name at the same time on AnyTone 878UV?

On the AnyTone 878UV I can choose to display the frequency or the channel name or frequency (Settings->Radio Set->4 Ch.Name). But seems to me like there's enough screen real estate to be able to show ...
3
votes
1answer
77 views

How to simulate two antennas in 4nec2

I need to simulate 2 helix antennae placed side by side, and see the resultant radiation pattern. But after adding the second antenna with a separate and when I try to simulate 4nec2, only simulated ...
17
votes
4answers
3k views

What defines music, per amateur radio regulations?

Sometimes when I access IRLP nodes, they have a very short melody telling you that you are connected; or when my local repeater's net begins, it does the famous doorbell 8-note sequence. What is the ...
0
votes
1answer
19 views

Is this result correct ? [ impedance cavity based on emtamaterials using CST Microwave]

In the contexte of my reaserch about antenna conceptions, I'm trying to simulate using CST Microwave a cavity antenna based on metamaterial structure and a slot antenna as a GND,However I got as a ...
2
votes
1answer
69 views

Substitute a car roof with radials?

I have a K40 Plus CB antenna, which is supposed to be attached to a car roof for the ground plane. However, I would like to set this up as a base antenna. Could I instead attach the ground to separate ...
1
vote
2answers
59 views

How many turns of wire inside 60 cm shielded loop antenna (9kHz - 30 MHz). How can I find this number without destroying the antenna?

Lots of information about shielded loop antennas is available on the internet. However, antenna manufacturers do not indicate the number of turns. How can I find the number of turns of a manufactured ...
0
votes
1answer
29 views

Does the 450D work with Winlink and allow Winlink to control changing frequencies and bands?

Will the 450D computer control program interface with Winlink and allow Winlink to change radio frequencies/bands?
0
votes
1answer
49 views

SWR jumps to maximum of gauge

(I'm asking this in the context of a Cobra 29LTD CB, but I think that it also applies to amateur radio in general.) In SWR mode, the needle swings all the way to the right, hitting the limit. The (mag ...
0
votes
2answers
95 views

How to use 75ohm (RG6) coax?

I know that there have been many similar threads on this, but I still need clarification. At the moment, the only thing I have is a 500' roll of RG-6 and a (very) tight budget, and I should be ...
2
votes
1answer
64 views

Help with Repeating 439 MHz signal

I have a remote wireless water tank level sensor. It transmits at 439 MHz with an apparent max range of 100 metres. Unfortunately I need about 200 metres. How can I extend that range?
1
vote
2answers
75 views

Troubleshooting 5BTV antenna

I have a Hustler 5BTV antenna i resurrected after a previous monopole succumbed to birds. It is giving me a world of trouble trying to get it tuned for resonance. For those not familiar with the ...
1
vote
0answers
63 views

Does the price of ham equipment normally rise during winter?

Recently licensed technician here, and going straight into my general class, I'm keeping an eye on cheap (sub-$400) HF radios. I keep reading articles that suggest used radios that normally sell for ...
6
votes
1answer
769 views

How to measuring ferrite core efficiency vs frequency

There is an unknown ferrite toroid. I would like to figure out whether it can be used in an audio transformer, or maybe in a 1:4 transformer on given HF frequency. The experiment I came up with is ...

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