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27

It's a feature not a bug. When turned on, the weather alert function checks the local NOAA station for its alert tone every 5 seconds for half a second... doing so takes over the receiver. I'd turned it on, and forgotten I'd done so; and how that feature is implemented never registered in my mind. Turning it off solves my "problem." Thanks to ...


16

There's a lot that can be said about lightning protection, but it usually boils down to doing all of these things: make good, low impedance connections to Earth bond all Earth connections together with a low impedance path have only a single point of entry to protected equipment A real problem when discussing lightning protection is that people will ...


6

QST magazine printed a comprehensive three part article in 2002 addressing lighting: Lightning Protection for the Amateur Radio Station. They are republished by the ARRL. QST June 2002, pp. 56-59 QST July 2002, pp. 48-52 QST August 2002, pp. 53-55 The surest way to protect your radio gear is to disconnect it from power, from the antenna, from your computer ...


5

I'd recommend one of two solutions: 1. Don't throw it out the window. Most lightning damage comes not from direct strikes but nearby strikes, which can still induce large-ish voltages on the feedline: not enough to make lightning, but enough to damage things. A couple feet of air between the feedline and the tranciever will protect against this. If you do ...


5

Here in EU it's perfectly legal to receive transmission on any frequency. Additional restrictions may apply if the transmission is not mean to be public, for example encrypted Wi-Fi networks or government agencies radios. (source: Telekommunikationsgesetz (TKG) § 89).


5

Here in the US, it is perfectly legal for you to listen and "download" the satellite data. Since the data is created by a public agency, it is considered to be in the public domain and not subject to copyright. On this website at http://www.weather.gov/disclaimer, you can find the following: "The information on National Weather Service (NWS) Web pages are ...


5

There is §97.205, which regulates repeater stations: (e) Ancillary functions of a repeater that are available to users on the input channel are not considered remotely controlled functions of the station. Limiting the use of a repeater to only certain user stations is permissible. So if the net is on a repeater, the repeater's control operator can decide ...


5

Many companies make lightning surge protectors. the install in the coax to your radio and divert the strike to ground. NOTE: THERE IS NO SURE WAY TO PROTECT YOUR RADIO EXCEPT DISCONNECTING IT FROM POWER AND THE ANTENNA. Search for polyphaser, they are well respected, MFJ also makes some lower cost options..


4

A lot of things will work electrically when wet, as long as the water film is thin relative to the size of the thing. For example, a wet dipole, no problem. A tiny coil where water droplets can short adjacent turns, not so much. Water getting in coax, either the feedline, or as part of a balun or trap, is a problem. The water will wick down the shield, ...


4

NLCs may propagate radio waves, according to a 21 May 2019 article on Polar Mesospheric Summer Echoes: The underlying physics of these echoes is still uncertain. A leading theory holds that the ice particles in noctilucent clouds are electrically charged, and this makes them good reflectors of radio waves. However, NLCs are not always visible when ...


4

You may be able to operate the device without consideration of your amateur radio status. CFR 47 Part 15.231 permits the low power use of 433 MHz without a license provided certain transmission repetition rates and maximum field strength rates are met. 433 MHz is commonly used by non-licensed home weather stations under part 15 provisions. If you need to ...


4

In my experience, the small amount of exposed thread on the SO-239 after inserting the PL-259 is the primary challenge in weatherproofing this connection. The first line of defense is to orient the housing with the connector pointing toward the ground to prevent water from pooling around the joint, particularly in the presence of ice and snow. I break the ...


3

There's no easy way to weatherproof it, but only you can know how bad the weather is likely to get, and balance the effort and cost of providing protection against the actual needed protection. If you do want to throw it outside and protect it, though, one method that works fairly well is to take a piece of capped PVC mounted so the cap is up, forming a ...


3

The overall antenna length being very close to a perfect 1 wavelength is the linchpin of the issue, I suspect. It is not surprising that it can be easily moved outside of the tuning capability of your tuner, as the impedance peak near resonance can be quite sharp (depending on the Q of the antenna system), allowing the impedance to change by hundreds or even ...


3

On HF, "range" is a function of propagation, which is affected by the signal's frequency, the solar flux, geogmagnetic conditions ("space weather"), the state of the ionosphere along the path the signal traverses, the number of "hops" required between reflective ionospheric layers and the earth, and whether the earth reflections are over land or saltwater. ...


3

What you need to do is follow the requirements of the National Electrical Code (assuming USA). This article covers it well. (ps. Failure to comply with NEC 810 is the #1 reason ham radio operators in the US have fire insurance claims denied, and why they have to buy ARRL's silly little insurance policy. If you follow NEC 810 and get permits for your work, ...


3

A discharge tube would serve to protect your rig from a close strike. Apart from that, make sure you have a decent ground for your shack. Having said that, it's probably not a good idea to operate in heavy weather. Unless absolutely necessary to continue operation, I'd go QRT, and disconnect the coax from the rig.


2

The Band Activity chart at DX Heat is a good way to evaluate propagation from the standpoint of "who is working whom, right now." Combining the color coded activity depiction with your general knowledge of when bands are more likely to be open can guide you as to what bands are opening and which are closing. The filtering tools allow you to target specific ...


2

Quick and easy propagation forecast tools are at VOACAP Online http://www.voacap.com/prediction.html and http://www.voacap.com/coverage.html for area coverage. Required are the transmitter and receiver positions, transmitter power, mode, antenna types, date and sunspot number. It does not consider the effects of geomagnetic ionospheric disturbances. The ...


2

Generally, keep equipment higher up and sheltered from the elements. The comment above about being unsympathetic to the desire for a foot-switch is not far off the mark too. A foot-switch is a comfort, and (as you have discovered) Field Day is not about comforts. If it's dry and pleasant out then sure, use a foot-switch. If it starts getting damp, unplug it ...


2

Properly applied tape is the appropriate solution: https://ham.stackexchange.com/a/12564/218 The box, and the connection between the connector and the box should already be waterproofed if the balun is made well. If not, you could always disassemble and put it back together with some silicone sealant, and add a weep hole somewhere for residual moisture to ...


2

You say your dipole's total length is 20 meters, and you are using it on the 20 meter band. When the dipole's length is equal to some multiple of the wavelength (1λ, 2λ, 3λ, ...) the dipole is antiresonant, and the feedpoint impedance is at a maximum. Being the worst possible match, it will require maximum range from your tuner. If the total length of the ...


2

Telemetry is explicitly allowed in §97.111. You must use an authorized "digital code", which probably means ASCII. And you must use a publicly documented technique. I don't see any specification in the manual of how this device works, but it's probably something simple like FSK, so no difficulty there. §97.309 RTTY and data emission codes. (a) ...


1

Noctilucent clouds are just clouds at a very high altitude. The temperature is low so they are formed by ice crystals. They are visible only when the sun is below the horizon but still shining on the clouds that are at very high altitudes. I can not imagine any effect on radio propagation. Maybe with visible light from a laser one could get reflections(??)


1

In the US, if you don't want to reinvent the wheel then your easiest solution would probably be APRS, more specifically the Citizen Weather Observer Program, which is a standardized system to send weather station data to the National Oceanic and Atmospheric Administration via APRS and/or the internet. Thousands of weather stations in North America already ...


1

Legal discussion To ISM or not to ISM, that is the question So, in Europe, 433 MHz is an ISM band – you could even operate a device there if you weren't a licensed Ham! That also includes the fact that if you choose to go for unlicensed operation rather than amateur licensed operation, the no-encryption rule, and the callsign rule (both of which frankly ...


1

Not really. You can try using the noise reducer control on your radio, but if the noise is really bad, it won't be that effective. Most of the noise you're talking about was due to lightning near where you were operating. Not much you can do about that.


1

The DXLab Suite includes PropView, a convenient front-end to VOACAP, which makes current and near-term propagation predictions. PropView works in conjunction with the other components of the DXLab Suite, so it works best when you use DXLab for all of your logging and operating functions. You can download N6BV's Propagation Prediction Files with the purchase ...


1

Here is a useful site for both long-term (monthly) and near-term propagation conditions. http://propagation.hfradio.org/ For VHF and UHF skip conditions (just in case you are interested) try here: http://www.dxinfocentre.com/tropo.html


1

If you want to get a more automated prediction, look for propagation prediction software (many available on the 'net) and plug in the data. Of course, it's still useful to know the basics, such as how the ionosphere works (see ARRL handbook), to understand what the programs do. And very important: Even if you take into account all of the data you have ...


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