[Lowfer] Antenna design idea question

[Joe]

Where was it naturally resonant?

And If i remember right a helical antenna usually has at least a 
naturally resonant length of wire if not mre  never less  than a full 
sized antenna.

Joe

Ed Phillips wrote:

>    I am aware to two such efforts to put a helical antenna on 1750 
>meters here in Socal.  Neither was very successful [performance 
>noticeably poorer than simple base-loaded 40 foot "push-up tower] and 
>I'm afraid you may go to a lot of work and be disappointed with the 
>results.  Randy Sedan, WD6ELU, went to a lot of trouble to make a 50 
>foot helical using 2" PV; it was white but I don't know the schedule.   
>I forget the wire size or turns but he wound it full from end to end and 
>I was part of the crew which assembled to help him raise it.  Turned out 
>to be a giant fiasco.  We had ropes attached in many places and guys on 
>ladders and on his roof to help get it up.  Turned out that the PVC was 
>more like limp spaghetti and we succeeded in getting both the top and 
>bottom perpendicular to the ground with the middle bent into a perfect 
>U.  From this point things went slowly because everyone concerned was 
>paralyzed with laughter and we all [some of us were OLD men] kept 
>getting the giggles.  Eventually it was maneuvered into place and guyed 
>so as to be straight.  It worked, sort of.  He had it base loaded and 
>was able to put out a signal from his beacon ELU but it was at least a 
>couple of S units weaker than the original mast and was almost inaudible 
>at my location, which is about 50 miles away.  I could copy the CW OK 
>but his SSB voice announcement was unreadable.  Bottom line was that it 
>was a lot of work for him and a great disappointment
>
>    While he had much less than a quarter wave of wire on the thing I 
>suspect the results would be no better with more wire.  The ITT 
>handbooks 'REFERENCE DATA FOR RADIO ENGINEERS' have lots of info on the 
>design of such helicals and perhaps a better design would have worked 
>but I doubt it.
>
>Ed
>W6IZJ
>IZJ [sometimes]
>
>Michael Lodico wrote:
>
>  
>
>>Good morning all you Lowfer's out there.
>>
>>I am trying to plan for an antenna for this winter and came up with an 
>>idea based upon what a ham did for a shortened 80 meter vertical.  The 
>>plan is as follows:  you take a 1/2 wavelength of wire and wind it on a 
>>rod like a solenoid so that it is shortened considerably.  He claims 
>>that it performs quite well.
>>
>>What I have in mind is to take 4 lengths of PVC heavy wall pipe, 4", 3", 
>>2" and 1 1/2", and wind a 1/2 wavelength of wire over the 40' length.  I 
>>would do this in 10' lengths and dope the windings in place to hold them 
>>and then connect them together at each joint.  At the top I would add a 
>>10' diameter capacitor hat.  By using the different diameters this gives 
>>me  anchor points for  Dacron guys.
>>
>>My question is has anybody tried this?  Is it a feasible design idea 
>>worth pursuing?  Any comments or feedback would be greatly appreciated.
>>
>>73,
>>Mike
>>K1EG
>>______
>>
>>    
>>
>
>
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