David Hoelzer
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  • Member for 6 years, 5 months
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Extra class first?
10 votes

An advantage of how the exams are administered is that you can take as many exams as you want (until you fail one) in one sitting. You start by taking the technician exam. Provided you pass that, you ...

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Noise & shielding, SDR Dongle
Accepted answer
5 votes

While the other answer is quite detailed, this one is much shorter and specific: I purchased and installed an aluminum RF shield for the dongle. The noise floor is significantly lower as a result! ...

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What is the etiquette for answering real world, non-contest HF SSB calls?
Accepted answer
4 votes

Welcome to amateur radio! While it is true that communications are supposed to follow a standard, folks can become lazy. You will find some frequencies where some folks have set up shop, apparently ...

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FT8 etiquette when no reply after responding to CQ?
Accepted answer
3 votes

There are a few things to have in mind. First, be reasonable. :) If there is no response, there's nothing wrong with trying again. There could have been interference that you cannot hear or the ...

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How to choose antenna "pigtail" pragmatically?
3 votes

BNC work well, make a positive connection, and are simple to crimp. I would suggest that you purchase a pigtail rather than manufacturing one because the SMA connectors are a beast to crimp. As far ...

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Can I use new 14500 batteries instead of AA with Yaesu VX-8DR?
2 votes

This would very much depend on how the device is wired internally. Is it possible that this will work? Yes. Is it possible that you can destroy your device? Yes. The current that can be delivered ...

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Learning morse, but I can't write fast enough?
2 votes

I'm by no means great at morse... but the morse elmers I know around here tell me that what happens is that, other than the first time you hear the callsign, you begin to "predict" what's ...

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Maximum occupied bandwidth and symbol rate for amateur satellites
2 votes

The maximum rates for the US are as follows: Frequency Rate 2 Meters 19.6k 70 cm 56k >902MHz. None You can find a reference from the FCC, a copy of the relevant section here, and another ...

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Do modern radios and power supplies require grounding for safety?
2 votes

I'm going to say "Yes," but refer you to the ARRL for a discussion that you might review to make your own decision. Safety is potentially a factor, but a bigger concern is that the ...

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What cause `multiply` has difference result between `float` and `complex` signal?
1 votes

If I understand your question correctly, the issue is that you have one graph producing a complex output of an FFT and the other producing a floating point output from an FFT. When you produce an FFT ...

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Which Frequency Band(VHF/UHF) is most useful for satellite in MEO?
1 votes

I'm not going to try to address the "Whys" (since I'm not competent to do so) but you may find the following useful. This is from the European Space Agency. There's also a really nice graphic to go ...

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