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It is a good reference documents as it covers the majority of the design criteria for such an antenna. Interesting the performance of the final design is pretty close to that of the popular PA0RDT and

Historically in the early days of coax, 50 Ohms was preferred for better power handling and 75 Ohms for lower loss. Over time 50 Ohms became the de-facto standard for transmitters and 75 Ohms for

Hello Simon, Saturday, January 1, 2022 Who is Mary and will your wife mind, that is what I want to know? ;) Happy New Year. The divorce courts are backlogged so you will have time to hide some of the

Quote “Whilst I realize there's no such thing as perfection in an imperfect world,” I beg to different..my Wife is allowing me to put up a top band 20m vertical with all its associated stuff, plus

The owner/developer (W7EL) of the well known EZNEC antenna analysis software has just retired and is now offering it for free to the amateur radio community. With this software you can simulate the

Hello Alan and Martin, Saturday, January 1, 2022 I should be able to give this a go tomorrow and will report back. Thanks. One downside of the loop's relocation and my making it a smaller

Hi Alan, OK, if this is problematic, then I'm not sure how the test I was thinking of can be achieved. My intention was to leave the loop in place with the ends shorted, so that the differential mode

Martin As Andrew said shorting the input is not a good idea and will not do what you think it will. Leaving the terminals open will but you need to disconnect both terminals.? The amplifier is a

Hi Chris, Happy New Year. I managed to take a listen today, and it's pretty good, and certainly a lot more sensitive than it originally was. The signal levels seem correct and the noise floor is now

Hi Larry, Yes that's a good cable. My main reason for suggesting 75 Ohm sat TV cable is that it's about the cheapest double screened coax that is readily available. But if you are really keen to use

Hi Tomasz, I have standardised on using 'F' connectors on all cables that carry both DC and RF, as this helps prevent accidentally connecting cables with DC onto a receiver input. Sometimes I use

The optimal length for a BOG for 80 meters for good RDF is about 200 to 250 feet. if you are space limited, try a VE3DO loop. vertical dimension is about 10 feet and horizontal length is between 20 to

Hello all, Just want to jump in regarding RG-58, etc... I highly recommend this double-shielded RG-58 substitute, https://messi.it/en/catalogue/50-ohm-cables-ham-radio/ultraflexibles/hyperflex-5.htm

Good question But why not just use a 50r plug? Unless missing something here..obviously does not matter about the slight swr difference, just as long as 50r plug fits 75r cable. Simon

[email protected]> wrote: Hi Martin, What about connectors for these cables? AFAIK for TV cables they make mainly Fs and BNCs, out of which only the latter are of any use for our purposes (not too

Hi Chris, That's excellent news, your perseverance has paid off, so well done for sticking with it. The downside is that your KiWi has now become more popular, so it's difficult to obtain an available

Hi Simon, Try G3TXQ Don't worry, it happens to the best of us. Rather too often in my case........ Regards, Martin

Hi Martin Opps how did i get that wrong!!!?? I was even looking at the filters at the time.. Apologies to g3tso, espically if still with us!! G3TSQ NOT G3TSO.. Sorry peoples ( getting old i guess)

Hello Martin, Alan, Andrew Ikin and all that contributed to this lengthy thread. Friday, December 31, 2021 Sincerest thanks to all, I moved the loop into the woods yesterday and today found 135 feet

For receive purposes there is really very little difference between the two. In practice neither the signal source (generator) or the receiver (load) are likely to be an exact 50 Ohm match, and in