talking local on 20 and 40 meters..

[KD2GOE]

this maybe a dumb question but talking to a friend that lives 3 miles away. using our fan dipoles we can barely hear each other on 20/40 meters. The 2 antennas are broadside to each other so what would be the reasons we cant hear each other?
i have made plenty of contacts on my antenna on 20/40 so i know i am sending out a single..
when it comes to his A99 and my Imax i we can talk on 10 12 & 15 no problem..

and our antennas are 20 ish feet in the air..

 

[543_Dallas]

That's NVIS propagation. Most of your signals are going straight up. If your friend were another 50 miles out you'd probably have no issues talking during the day on 40. Try using a vertical antenna if you can swing it.

 

[Tallman]

Or you could switch to vertical polarization.

 

[KD2GOE]

That's NVIS propagation. Most of your signals are going straight up. If your friend were another 50 miles out you'd probably have no issues talking during the day on 40. Try using a vertical antenna if you can swing it.

"Most of your signals are going straight up" that is what i was thinking was going on..
it was just some thing we wanted to try now that he has a working 20/40 meter antenna and i was shocked how week we where to each other. it is not some thing we want to do normally if we are going to have a QSO we would just run it on 10, 12 or 15..
i am working on a 20/40 vertical but i wont be able to set one up till i move..

 

[543_Dallas]

You could use your phan dipole as a Marconi. Tie the center conductor and shield together at ground level and feed the whole thing against some ground radials.

You can make up some connectors to switch between configurations easily. It will require a tuner at the feedpoint to work very well. Tuning in the shack makes for lots of coax loss.

 

[Road Squawker]

"Most of your signals are going straight up".....

No, it's not. it's going in the same direction and elevation angles it goes to when you talk to someone 1000 miles away.

the antenna doesn't "know" you are talking to someone close.

In fact, IF the signal was going straightup (a cloudwarmer antenna) , then you would be able to hear each other.

There is no NVIS propagation on 20 and very little on 40.

put up a 44 foot wire and work him on 60.

 

[wavrider]

https://en.wikipedia.org/wiki/Near_vertical_incidence_skywave

Little time spent on google and your question is answered with explanation.

 

[KD2GOE]

https://en.wikipedia.org/wiki/Near_vertical_incidence_skywave

Little time spent on google and your question is answered with explanation.

Thanks ill take a look
I may have not been wording it right when looking on google when i did. Why i ask on hear i am still a rookie though it might start up a good conclusion..

 

[KD2GOE]

I am working on a vertical antenna right now it is 24' 6" need 1 more pipe to hit 32' for a 1/4 wave 40 meter antenna and then i was going to coil load it for 80 meters.
I made it out of wire conduit thicker to thinner with a 102 steel whip as the top. I brazed stainless slugs that i made on the CNC that are tapped with 3/8-24 to connect end to end.
I shod have cut slits in to the pipe and used hose clamps so i can claps it in on its self. as i want to be able to move it around when camping.. opps
but that should accomplish what i want to do i would think..

 

[543_Dallas]

No, it's not. it's going in the same direction and elevation angles it goes to when you talk to someone 1000 miles away.

the antenna doesn't "know" you are talking to someone close.

In fact, IF the signal was going straightup (a cloudwarmer antenna) , then you would be able to hear each other.

There is no NVIS propagation on 20 and very little on 40.

put up a 44 foot wire and work him on 60.

Very little NVIS on 40? Do you use HF at all? If you do is it just random DX or people you talk to on a weekly basis? The same phenomenon happens with close locals on 75 at night. I can barely hear guys across town on a low horizontal antenna but the guy 50+ miles out hears him fine.

You're right about the antenna not being able to think for it's self though.

 

[wavrider]

http://www.hamuniverse.com/antennas.html

Some good antenna ideas.

IF you are wanting local rag chews on 40 meters,, a low hung half wave dipole is the ticket. high angle of radiation,,cloud warmer,

vertical are for DX on the lower bands. experiment,,enjoy,,have fun.

 

[543_Dallas]

Verticals are great for DX but they can work better than a nvis antenna for someone that close to him. Good local nvis communication seems to around 30 to 40 miles.

There's too much bs out there about nvis work. Like the ones that say the antenna can only be a few feet above the ground to work. Looks good on paper but in reality it really sucks. Put the thing up as high as you can.

Some notes on that from someone more credible than me. https://www.w8ji.com/nvis_n_v_i_s_antenna.htm

 

[Road Squawker]

I stand by the "very little" on 40,....
7 Mhz is at the high end of NVIS propagation.

Putting a dedicated NVIS antenna "as high as you can get it" kind of defeats reducing QRM and increasing SNR..

 

[543_Dallas]

If you think lowering an antenna is how you increase performance let's just agree to disagree. I understand the theory but the reality is ground loss kills performance. It's also a good way to piss off your neighbors.

Do you actually ragchew with the locals on the lower frequencies? Guys with higher antennas are stronger and hear better. The few that have verticals are very strong at close distance so to say they are only good for dx is not true.

Theory and terminology aside the important thing is to put up something that works. Another observation from the lower frequencies is the gurus that are always quoting from the internet and telling someone how to improve their signals are the hardest ones to copy. If you want to test antenna performance hit the AM button on your rig. Wet noodles transmit fine on ssb.

 

[2RT307]

40 has been really long lately during the day. I can normally talk to guys in Houston, San Antonio, Austin/Hill Country, Shreveport, NW Arkansas (you listening, Homer?) and OKC with no problems at all. I can barely hear them lately... everything is long for the most part. Wish I could put my Imax up for 10, 12, and 15, but I'll have to live with stealthy wires for now.

73,
Brett