Fan dipole questions..

[BJ radionut]

http://www.randl.com/shop/catalog/man2/alpha delta/dxcc.pdf
Might be a choice to consider...If nothing else interesting reading.
Balun on dipoles...95% of ones I have made...never used one...Also when trying to "stretch" bandwidth a balun can create issues. They are used for Totally resonate antennas...and don't like to be stretched with a tuner...You end up giving up power in heating the balun.
All the Best
Gary

 

[JoeDirt]

MFJ-941E

Other issue is the powerlines that run thru those trees though.. and my neighbors are literally 15-20' behind me.

I dont live in a park but my neighbors are just as close. I use a inverted V 140' doublet (max length i can fit), the ends are tied to the neighbors fence.

I also have power lines in my back yard, where is your transformer? Most parks are all low voltage insulated wire.....

I would recommend the same setup but in a V (non inverted) configuration, run ladder line with a feed point close to the ground (not seen) then run as much thin gauge wire (20 gauge insulated gray or brown) through the trees as you can get away with (more the better), zigzagging if needed. That would give you a nice discrete multiband antenna, no common mode or band restrictions like with a fan dipole. On HF the wires do not need to be in a straight line, hell wrap them around a tree trunk or the branches no way they neighbors are going to see that! Higher is not always better......

 

[CB590]

Anyone know the center frequencies to tune for voice for General class?

For 80/40/20/10

 

[CB590]

I came up with this for tuning the center of the General class phone/voice:

3.9mhz 80m
7.2375mhz 40m
14.2875mhz 20m
29mhz 10m

This look right to you folks??

 

[543_Dallas]

29mhz is where you find AM on 10m. Its mostly a ghost town. Most voice activity will be between 28.300 and 28.500.

http://www.arrl.org/graphical-frequency-allocations

 

[CB590]

29mhz is where you find AM on 10m. Its mostly a ghost town. Most voice activity will be between 28.300 and 28.500.

http://www.arrl.org/graphical-frequency-allocations

So go for 28.400 for center of band?.

 

[543_Dallas]

So go for 28.400 for center of band?.

Yep. That's where most of the action is.

 

[w9cll]

Yep. That's where most of the action is.

When there is action, personally I wouldn't waste time with a dedicated 10m element. Go for 17m, much more activity there.

 

[543_Dallas]

When there is action, personally I wouldn't waste time with a dedicated 10m element. Go for 17m, much more activity there.

Good point. If I had to pick one it would probably be 17. When I do find someone on 10m it usually doesn't last long before they fade away or they just want to exchange callsigns and signal reports.

 

[BJ radionut]

Also if you shoot for 7.100 to be your best match on 40m
(remember DX window 7.175-7.200)...very likely close to 1.5/1 center of phone band...
Then you will likely have a good match on 15m also.
GL
All the Best
Gary

 

[JoeDirt]

Just feed it with ladder line and forget about it! 4 Bands can get tricky, 3 seems to be ok.

 

[CB590]

I'm doing 40/20/10 for the fan..

@BJRadio.. Going for 7.2375 for 40m as center for the phone/voice

Not really looking at CW/RTTY/Data ranges. Have no key.. haven't learned Morse yet. Don't have data cable or software either..

The fan is so I can just hopefully 'bypass' the tuner for 40/20/10 and if needed I can ''tune" my other bands on the old end fed as I do now.. I can tune 80/60/17/15 currently on that.

The 941e has 2 antenna options.. and also bypass option for either..

 

[w9cll]

The fan is so I can just hopefully 'bypass' the tuner for 40/20/10 and if needed I can ''tune" my other bands on the old end fed as I do now.. I can tune 80/60/17/15 currently on that.

I think you're going to find that the "Fan" works better than the end fed. I played with an end feed for a while and while it worked ok I kept finding myself going to to my fan. I finally took down the EF. On thing to keep in mind with EF's is they like to radiate into everything if you feed them power.

 

[N0NB]

Balun on dipoles...95% of ones I have made...never used one...Also when trying to "stretch" bandwidth a balun can create issues. They are used for Totally resonate antennas...and don't like to be stretched with a tuner...You end up giving up power in heating the balun.

It depends on the style of the balun. Ferrite transformer type baluns can suffer from the problems you describe. Choke style baluns that use ferrite beads over a length of coax should be more immune to the issues.

Walt Maxwell was among the first to promote choke baluns in his Another Look at Reflections series published in QST in the '70s and later formed the basis of his Reflections, Reflections II, and Reflections III series of books. I have the original and III but screwed around and never ordered II.

I've used choke baluns in the past and had excellent results even doing naughty things like tuning the WARC bands on a 40/20/15/10m trap dipole. The balun fared well, the traps, not so much.

 

[CB590]

In other news..

Just measured my mobile home.. apparently I have 34' from my current 9:1 un-un location mount to the front of the trailer.. so I can just squeak the 33.8' to get this 40/20/10 fan up.. going left up the tree I get like 40'..

So get 1:1 balun, (I already have 12THHN wire, and S40 1/2" poly gray for the spacers) and put together and up..

Should I leave on a inverted slope going 15' on one end to 10' at mounting point, and up to 27' in the tree ?? I can lower the tree end to be same 15' as in the front..