# Tag Info

Accepted

### How does an SWR meter really work?

Dispelling the Myth To begin with, the typical HF SWR meter does not have the ability to separately sample the forward and reverse power, voltage, or current. Any description of the device or its ...
• 18.1k

### I have 60 feet of coax but only need 20 feet; can I loop up the excess?

There's nothing inherently wrong with “looping up” extra coaxial cable. In fact, a neatly wound coil of coax can function as an air-core choke balun (“ugly balun”) which is useful for some antenna ...
• 22.7k
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### Is there an optimum Antenna Feedline Length for mobile installations?

In the absence of common-mode currents, then the optimum feedline length is 0, because a longer feedline only increases your feedline losses. These losses are due to the resistance of the wire, ...
• 49.8k
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### Why is my calculation for added length of coax for a double cross antenna different to everyone else's?

The difference is the "Velocity factor". A 36cm long physical coax wire of this type is electrical 54.4cm long. Different types of wire have different velocity factors. https://en.wikipedia.org/wiki/...
• 126
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### Is "low loss" cable required for HF?

Your question seems as much about psychology as much as technical concerns. We mainly favor the technical questions, but I'll take a stab at the psychological aspects also. All of you, please feel ...
• 8,922
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### Why isn't twisted pair used for feedlines?

Balanced lines (of which twisted pair is a special type) really have an upper frequency limit; you can't use them to transport 1 GHz (well, you can, but the smallest variation in direction or distance ...
• 13.3k
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### Soldering PL-259.. with a torch?

Our friends in the UK and other parts of the world are now wondering how you could even begin to solder a PL259 connector with a torch (aka flashlight)! But in their vernacular, you of course are ...
• 18.1k
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### VHF 50 Ω Antenna Over 75 Ω TV Coax

I will need a UHF/VHF diplexer on either end to suitably merge/split the signals from each antenna Yes, this is correct. A tangent: If you wanted to save some money by using mass-market parts, ...
• 22.7k
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• 49.8k
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### Understanding coax radiation and "current on the shield"

Perhaps some of my confusion comes from an audio background, where one has "balanced" and "unbalanced" cabling in a way that is easier for me to understand: an unbalanced cable is simply a signal and ...
• 49.8k
Accepted

### RG-174 to pull signal from 1st IF?

So, you say: I don't care if the signals are delayed. I'm just tapping the line out to a pan adapter. I am most concerned about influencing the existing function of the receiver And that's exactly ...
• 13.3k