Amateur Radio Stack Exchange
Amateur Radio Stack Exchange

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1500 questions
7
votes
3 answers

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? If this course of action is allowed and not ill…
Gregory
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2 answers

Apps and or equipment needed to document local interference?

A neighbor ham user recently started doing something that causes very noticeable feedback/buzzing in AM radio as well as any device that uses a wired microphone (such as a gopro with wired mic). Before I approach this individual, I'd like to make…
a coder
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7
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8 answers

VHF/UHF digital single-frequency repeater without duplexers?

Some digital voice protocols are time slotted (TDMA), i.e. the transmitter of a station is not on all the time, and multiple stations may transmit digital voice on the same frequency at the same time by transmitting small digital bursts, one by…
oh7lzb
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7
votes
1 answer

Using more than 400W in the UK

With a full amateur license in the UK, up to 400W can be used - however, there are cases that might call for higher power, such as bouncing signals off the moon. Is there any way I can obtain permission to use a higher power, even if this is…
berry120
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7
votes
2 answers

What are CQ/ITU zones used for?

There are already questions about the definition of CQ zones and ITU zones, but there is no information about what these zones are used for (and Google brings up various maps but no explanation). (Is this something a non-US novice-class amateur…
Georg DO1GL
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7
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3 answers

Broadcasting a WiFi SSID long-distance

Which equipment would be good for broadcasting a WiFi SSID the longest possible range? We're making an orienteering race in a forest and would place a sender somewhere high over the trees, transmitting a WiFi signal into the forest. The SSID should…
sune
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7
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2 answers

Do aprs.fi and APRS-IS use the same credentials?

I have an account/profile on aprs.fi, and now I am trying to use APRSdroid, which requested my credentials. Can I use the password from aprs.fi for it? I am unable to register/submit my application through TQSL because my country is not on the list.…
harayz
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7
votes
1 answer

Can I touch the ground of a PWR/SWR meter?

I'm planning to build a 5W PWR/SWR meter very similar to this design by G3YMC, but with two meters: I'd like to put it in this metal box, and use the box as ground. However, the bottom of the box would then also be ground, and I may accidentally…
user885
7
votes
3 answers

decibels as ratio and dBm as absolute values

I am just trying to understand the nitty gritty of using decibels and absolute measurements in dBm. I see them referred to routinely in RF, and using reference sheets I can understand enough to make sense of gains and losses, but I would like…
nanker
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7
votes
4 answers

Shaving Quartz Crystal for New Frequency

Back in the 1960s during my Novice days I operated on the 40-meter band only with 4 different quartz crystals that determined my transmitting frequency with my Eico 720 CW transmitter. I had heard about other old-timers who would shave (or…
K7PEH
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7
votes
2 answers

Center frequency spike on software radio for mismatched/disconnected antenna

A while ago I was using a software radio receiver to perform some antenna analysis. I left the spectrum display on while disconnecting the cable and noticed that when the cable was disconnected I could see a very large spike in the frequency…
mtrberzi
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7
votes
1 answer

Is it possible to remove the previous callsign information?

I had a name change some years ago and had a new callsign generated. But the FCC keeping a record of my previous callsign puts me at risk of an abusive ex finding me. Is it possible to disassociate the old callsign from my FCC record so there's no…
MuffintopBikini
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7
votes
3 answers

Has any computer been hacked over amateur radio digital modes?

We don't normally worry about security in ham radio, because we can't encrypt our transmissions anyway in the vast majority of cases. Some niche protocols support authentication of messages, but that's it, unless you're controlling satellites. There…
Someone
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7
votes
1 answer

How do you solder/crimp a 90-degree BNC connector?

I ordered this 90-degree BNC connector, but I'm not sure how to connect the center pin. The back of it looks like this: The small screw plate threads into the back when you're done connecting the wire. But how does the wire connect? The hole is…
KJ7LNW
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7
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7 answers

Amateur Radio License: USA or Canada, does it matter?

I'm hoping to take the exam in the fall. My question is, does it matter whether I do so in the US or Canada? I would like to operate the radio at my school in Canada, but I do get the chance to come the US, so I can potentially take the exam there.…
user1488
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