Glenn W9IQ
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Equation 1 as proposed in the article has two primary shortcomings: It does not address losses in the line. As a result, the formula may overstate the maximum peak voltage. It requires that ZG (the ...

It appears to be a "vertical" CB ground plane antenna that had been mounted or stored in a horizontal orientation. It is not suitable for effective TV or FM reception. It is also noteworthy that one ...

Your line of sight to the ship transmitting the AIS signal is one of the more limiting factors. Usable AIS VHF signals will travel just slightly further than line of sight conditions. This is known as ...

Since you know the complex reflection coefficient, you can simply use this formula to calculate the complex impedance: $$Z=Z_O\frac{1+\rho}{1-\rho} \tag 1$$ Assuming the characteristic impedance is ...

AM synchronous detection will certainly reduce or eliminate selective fading. It generally isn't implemented simply due to the increased cost and complexity. But you will certainly be pleased with its ...

The primary factor to consider is the directivity of the parabolic antenna. It is given as: $$d=\frac{(\pi D)^2}{\lambda^2} \tag 1$$ where D is the diameter of the dish and $\lambda$ is the ...

Near and Far Fields To mount the two antennas in close proximity to one another, you should minimally ensure that neither reactive (near) field interferes with the reactive field of the other in ...

Let us say that I want to stick with a non directive antenna, because I do not know in advance the direction I will be receiving from. With this as the starting point, consider that there is no real ...

The formula you are seeking comes from the Shannon-Hartley theorem: $$C=B\log_2\left(1+\frac{S}{N}\right)\tag 1$$ where C is the channel capacity in bits per second, B is the bandwidth in hertz, S ...

If you wish to transmit a measured parameter under US FCC Part 97 regulations, you would be operating under the telemetry rules. This is defined as "A one-way transmission of measurements at a ...

It depends... With a 100% steady modulated carrier, the PEP will be 4 times the unmodulated carrier power. The average power under this condition will be 1.5 times the unmodulated carrier power with ...

It appears to be typical moisture ingress. The joint between the coax and the connector is not inherently waterproof. A damaged jacket can also be the source of moisture ingress. Normally the ...

You need to install the Icom USB drivers on your PC. You mentioned that your PC is running Linux but I am not aware of any Linux drivers from Icom - I only see Windows support on their website. Once ...

As a new ham, you may have more success answering a CQ since you will then know that you can at least hear the other station over your local noise. Answering a CQ also requires less finesse so you are ...

Poor Loop Gain The small (<0.1 wavelength in circumference) loop antenna has very low gain. While the size somewhat lowers the directivity, the primary reduction in gain is due to inefficiency as ...

You are correct that there is a clear correlation. Perhaps your Smith chart does not have the following scales along the bottom?: The technique is to use your compass to measure from the center of ...

The Current FCC Regulations (as of July 2018) Parts 97.305(c) and 97.307(f) regulate digital modes primarily by symbol rate. The table in 97.305(c) maps bands/frequencies to specific symbol rate ...

126.3 MHz is the Talkeetna CTAF (Common Traffic Advisory Frequency). You may have heard some traffic on this frequency while in-flight. Pilots use this to advise other pilots that they are in the area ...

The antenna is matched to be 50 ohm at A (Fig. a). So, to measure it in practice, the author designed a 50-ohm transmission line which connects A to B. Am I right? The antenna by itself is not a 50 ...

The transmissions quoted most likely are not occurring. The quantity of frequencies is suspicious for any broadcasting service and some of the frequencies themselves are not suitable for broadcasting ...

I suspect the primary reason that the kit supplier does not ship the kit with prewound toroids is that there is insufficient volume to make it economical to have them commercially wound. A second ...

If I wanted to build a mostly-portable-but-still-comprehensive kit to use in emergencies, either my own, or simulated ones through ARES or RACES, what should I put in the kit? If you are active in ...

This depends largely on the elevation and clear line-of-sight conditions. You will find your answer under this question Could I expect 12 mile range with the GXT1000VP4 radios? included a simple ...

These radios will operate largely on a line of sight basis with a slight boost from refraction. This is known as the radio line of sight. It is given as: $$D\approx1.41\sqrt{H} \tag 1$$ where D is ...

An RF tag system is designed to function in the near field of the antennas. The frequencies involved are in the 13 MHz range and the antennas used in these applications are defined as electrically ...

Based on your description, I would suspect moisture damage. Moisture ingress in coax cables typically results in the corrosion of the copper braided wires in the shield. The oxide that forms ...

The answer to your question involves both technical and regulatory issues. Technical Considerations Radio signals can travel between two locations on earth either by line of sight or by propagation ...

It is very difficult to help you with analyzing a circuit when clearly, and as you stated, your measurements were in error. The electrically fractional wavelength loop will have a very low feedpoint ...