Thank you for all the good input. Here is a bit of additional information on
my plans. Initially I was considering a 40m yagi but the wind loads scared
me off , so now I am planning on putting a 40m four square in the back 5
acre field. Also I have enough tower to put up a second 120 foot tower in
the back 5 acre field. I could hang an 80m four square dipole array from it
and also load it for 160m. So the tower that we are discussing which is by
the house will be used for 20m through 10m.
73 Mark N1UK
----- Original Message -----
From: "Jim Thomson" <jim.thom@telus.net>
To: <towertalk@contesting.com>
Sent: Sunday, 23 May, 2010 10:10 AM
Subject: [TowerTalk] Optimium Tower Height
> Subject: Optimium Tower Height
>
>
> Date: Sat, 22 May 2010 05:48:41 -0400
> From: Pete Smith <n4zr@contesting.com>
> Subject: Re: [TowerTalk] Optimium Tower Height
>
> This is also the advice I was given 15 years ago by a very well-known
> and technically accomplished local multi-multi owner - he said if you
> only plan one tower, make it 100 feet. I altered my plans accordingly,
> and am very glad I did it.
>
> 73, Pete N4ZR
>
> On 5/21/2010 7:35 PM, john@kk9a.com wrote:
>> According to (sk)W2PV's Yagi Antenna Design book a good height is 1 1/2
>> wavelengths high.
>
> ## 1.5 wave lengths is 100' on 20m... but is 3 wave lengths on 10 m!
> He doesn't mention a 40 m rotary dipole or 40m yagi in his proposal.
> Even if wire ants used on the low bands... they will work better up
> 100' vs 70'. If he wants to shunt feed the tower on 160m.. again
> a 100' tower will work better vs 70'. Considering the 100' tower is
> 2 wave length's on 15M.. and 3 waves on 10m.... he might want to
> consider either a tic ring or side mount rotor... and a 2nd TH7 down
> the road...at a lower height... say 50' [just above guys]. If that is the
> case, you will want to consider the guying levels used... and whether
> the 2nd TH-7 will rotate freely.
>
> ## even a 40m rotary dipole is a good ant,..if up high enough. The F/S
> alone will justify it. A friend had 4 x tic rings on 160' of 45-G.. + a
> protistel on top. You can hang a lot of AL off rohn 45g.
>
> ## 2 x TH-7's @ say 55' and 100' would work very well...esp if they
> can be pointed in diff directions. Then toss in the top,bottom, both in
> phase,
> both out of phase combo's, then u have a killer combo. You might even
> want to make it higher..like 110-130'.... then you have room to hang all
> sorts of stuff on it... including fixed yagi's.. or vhf/uhf ants.
>
> ## if you have room for 100' to 130'... I'd suggest to go for it. A 2nd
> tri-bander, lower down will take care of the high angle stuff..if needed.
>
> Later........ Jim VE7RF
>
>
>
>>
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
>>> I have started my Rohn 45 tower projhect. I am planning to put a
>>> Cushcraft
>> A3WS and a TH7DX atop this tower. I was planning on erecting a 100 foot
>> tower but a fellow ham suggested that that might be too high. What in the
>> groups informed opinion would be an ideal height for these antennas?
>>
>>
>> I appreciate your input
>>
>>
>> 73 Mark N1UK
>>
>> _______________________________________________
> _______________________________________________
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>
>
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