[TowerTalk] Single tower and 3 monoband yagis - "Christmas three"

[Billy Cox]

Good Afternoon Fudo,

May I suggest before you invest into doing this, you review W6QHS/W6NL
and N6BT's published materials on the "christmas tree".

Both found the performance, regardless of which yagi that you place on
the top, was much less especially on 10 and 15.

Many years ago, I helped friends put up (despite all my reservations) 
a 3L40, 5L20, 5L15, and 5L10, all Telrex, on a 3" mast that was at 
best perhaps 14' in exposed height on 100' of Rohn 55G.

It was simply too many antennas placed too close together. I still
believe he would have been better off with the 3L40 and a larger
tribander, something like the C31XR or similar option today and use
individual feedlines for each band?

Hope this helps and Season Greetings to you and yours!

73 de Billy, AA4NU

----- Original Message -----
From: "Fuad Arnautovic" <infobih at infobih.com>

Thank you

I will probably try 10/15/20 from lowest to highest with spacing of app. 8 feets.

73 Fudo

________________________________________
From: TowerTalk [towertalk-bounces at contesting.com] on behalf of n8de at thepoint.net [n8de at thepoint.net]
I agree with Joe, W4TV, but, would add the comment:

PUT THE 20M monobander on TOP of the stack .. that is .. invert it,
with the 10m on the BOTTOM.

73
Don
N8DE



Quoting "Joe Subich, W4TV" <lists at subich.com>:

>
> Unless the monobanders have been designed to operate in a stack
> ("Christmas tree"), stacking them as closely as will be needed to
> stay within your 5m mast will certainly reduce their performance.
>
> If the monobanders have been optimized to work in a stack, use the
> spacing for which they were designed.
>
> 73,
>
>    ... Joe, W4TV
>
>
> On 2014-12-11 9:16 AM, Fuad Arnautovic wrote:
>> Hi all
>>
>> I need advice from some more experienced with stacking about possible setup.
>>
>> Have self-standing tower abt 18 mtr, mast 50 mm (2") 5-6 metres long
>>
>> Antennas are three monoband yagis as follows
>>
>> 20m 4el 9,5m boom
>> 15m 5el 9,6m boom
>> 10m 5el 7,6m boom
>>
>> Does it "Christmas tree" setup working well with this monobanders?
>> What is your recommendation for vertical spacing between? Does 2"
>> mast is strong enough to support all them.
>>
>> I would install lowest antenna for 20m then 15m and on the top 10m
>>
>> I know that is compromise against performance and radiation
>> pattern, but actually cannot install another tower
>>
>> Please help
>>
>> Thanks in advance
>> Fudo, E73CQ