General > General Technical Chat
Broadcast/Shortwave Aerials? Confusion...
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Kerlin:
That's it he has done it.
Notice how I predict he will just make an excuse, and he does, multiple ones.
But it went further than that he skipped over all my suggestions and ignored them.
I wasted my time answering.
That's it he has done it, from now on I must resist the temptation to help people, just sit on the side.
It happens too often on all forums.
tkamiya:
I'm not sure if I can achieve a balance between being simplistic and theory, but here goes....

Antennas can be divided into two categories.  Resonant type and non resonant types.  Dipoles are basis of resonant type and random wire, ie. long wire antennas are non resonant types.  They both work and work well.

Resonant types are cut for a certain frequency.  Length of element is based on half a wave length and for exact formula, you can easily look up various literature.  This is a very efficient form of antenna but has one major draw back.  It's good for one frequency, and odd multiple there of.  So you will need multiple of these to cover various HF bands.

Non-resonant types are often just a random length of wire stretched as long and as high as possible.  It works well on all frequencies if you have a proper matching network, and a suitable and good grounding system.  For listening purpose, just a wire as long as possible will perform respectably.  Basic rule applies here.  Longer, higher, away from noise sources, and do it safely.  That's it.  This is the type I have.  I also have a very basic grounding system.  Not very efficient compared to resonant types, but most broadcasters are in Multi-Killowatt ranges on HF bands.  Good enough is, really good enough.

You can get infinitely  complex from here, but I don't think it applies here.  I don't recommend over-thinking this at beginning.  Soon enough, they will catch up to you.
tautech:
It doesn't need to be anything more than a long wire hung between the house/shack and a tree with insulators at each end and end fed.....with the obligatory lightening arrestor and ground if leaving gear connected or listening in shitty weather.
Dad listened to SW from all over the world in the 40's and 50's from little old NZ mind you many were directional SW broadcasts towards downunder.
In my teens I played a bit with SW too and got contacts from OZ, US and EU with just a rudimentary length of wire and cheap SW transistor radios.
Dads stuff was all home built often with handmade coils and all valve based. Well remember him teaching how to make a wave trap wound on a toilet roll tube.

There's certainly no need to overthink it for it to just work.
 
vk6zgo:

--- Quote from: tautech on July 22, 2020, 10:07:58 am ---It doesn't need to be anything more than a long wire hung between the house/shack and a tree with insulators at each end and end fed.....with the obligatory lightening arrestor and ground if leaving gear connected or listening in shitty weather.
Dad listened to SW from all over the world in the 40's and 50's from little old NZ mind you many were directional SW broadcasts towards downunder.
In my teens I played a bit with SW too and got contacts from OZ, US and EU with just a rudimentary length of wire and cheap SW transistor radios.
Dads stuff was all home built often with handmade coils and all valve based. Well remember him teaching how to make a wave trap wound on a toilet roll tube.

There's certainly no need to overthink it for it to just work.

--- End quote ---

Exactly!
Old domestic valve radios were quite sensitive, & had relatively high impedance inputs.
Many will give reasonable results with quite abysmal antennas.

When I was a kid, we lived "in the bush" (not that far from Perth WA, but we didn't have Mains  power).
Our home radio was a valve portable, & after local broadcast hours we could hear a lot of distant stations on MW, usually from the Eastern States, but on several occasions, the USA.

We had a decent end fed outside antenna attached to a tree, which then sloped down into the house, where it plugged into the portable's "external aerial" socket.
An earth lead was provided to a quite small stake in the garden, but on occasion, the earth lead fell out with no obvious change.

My brother used the same antenna for his regenerative receiver, which used battery valves.
He listened to a lot of HF stuff on that antenna.

When "Z" call amateurs finally got HF privileges, I picked up a Yaesu FT301 transceiver, brought it home, grabbed some random wire, chucked it out the back, connected up the radio & had a listen to the 20m  band.
The radio was seemingly "deaf as a post", & I was devastated, but went ahead with putting up a 20m dipole.
Now the band was "jumping with signals"..

Radios with low impedance inputs don't play well with random length anennas without any matching circuit.
Scungy old mantel sets work well with such antennas.
GlennSprigg:

--- Quote from: Kerlin on July 21, 2020, 07:59:02 am ---That's it he has done it.
Notice how I predict he will just make an excuse, and he does, multiple ones.
But it went further than that he skipped over all my suggestions and ignored them.
I wasted my time answering.
That's it he has done it, from now on I must resist the temptation to help people, just sit on the side.
It happens too often on all forums.

--- End quote ---

???  Really... what is your problem Kerlin ???
Firstly, I DID take notice of the TECHNICAL info you spoke of, & I thanked you/others for it!!  :scared:
In fact, I copy/pasted ALL the tech info from everyone, including you, and saved it all in a file.  :P

You say you 'predicted' that i would & did make multiple excuses... ?????? What drugs are you on??...
I simply re-explained what I was trying to find out, in a simplistic way, & considering my limited time
on this good Earth to take it all in!!  I'm sorry I don't come up to your 'standard'...  ???

   I wasted my time answering.
   That's it he has done it, from now on I must resist the temptation to help people, just sit on the side.
   It happens too often on all forums.
Sigh...   :palm:  EVERYONE else here spoke in a friendly manner, and were respectful. Other than your
technical words, and ESPECIALLY in your last 'reply'... you seem to have a MASSIVE chip on your shoulder!
If that happens "all too often" on "all forums", what may that suggest to YOU!!   |O
My life is literally too short to converse with you further.  :--
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