On 5/18/2011 6:40 AM, dalej wrote:
> Wilco on the setup Roger. I'm wondering where you place the choke balun in
> your coax? I have one here by Balun Designs and it's in the shack on the
> antenna side of everything else. Would it be better out by my remote switch
> at the base of the tower? It probably doesn't make a lot of difference.
I have one on the coax at the feed point to keep common mode voltages
down and another where the coax reaches the tower. Each is 6 turns of
Davis BuryFlex(TM) on 5 #31 mix cores for both 75 and 40 meter, center
fed, half wave slopers. See pages 35 and 36 as well as Fig 36 of
http://www.audiosystemsgroup.com/RFI-Ham.pdf , Jim Brown's (K9YC) "A
Ham's Guide to RFI, Ferrites, Baluns, and Audio Interfacing"
73
Roger (K8RI)
> 73
> Dale
>
>
>
> On 18, May 2011, at 3:38, K8RI wrote:
>
>> On 5/18/2011 4:05 AM, dalej wrote:
>>> Nice installation Roger. Thanks for the article and pictures. Mine is not
>>> as elaborate, but I do have three ground rods all tied together at the base
>>> of the tower and one at the shack entrance about 30 feet from the tower.
>>> The station ground is tied into the cold water copper pipes which is tied
>>> to another ground on the other side of the house at the service entrance
>>> and it is tied in to the street side of the water meter too. The entire
>>> ground system here is all tied in to the tower grounds with heavy solid
>>> copper buried wire. We don't get the lightning storms here like say in
>>> Tucson Az or Florida, but we do get some. Sometimes rather intense..
>>>
>>> I was gonna say that (I have not had any lightning damage here in 38
>>> years), but I'll just say I've been lucky so far.
>>>
>> Thanks on the comments,
>>
>> Even with 32 or 33 Ground rods cadwelded(TM) to over 600 feet of bare #2
>> copper, I have claim luck, particularly as many times as the tower has been
>> hit.<:-)) It's taken all those hits without damage...that I know of, but
>> the next one could blow everything apart. You never know, but it doesn't
>> hurt to try and stack the odds in your favor.
>>
>> Keeping the antennas at DC ground along with current baluns helps keep the
>> noise down too.
>>
>> 73
>>
>> Roger (K8RI)
>>> 73
>>> Dale
>>>> I hope when you disconnect things inside you ground things outside.
>>>> A floating antenna or antennas make a tempting target for lightning and
>>>> from there it's a short jump to the house.
>>>> With the ground system here, I rarely disconnect anything and have had
>>>> no damage from numerous strikes to the tower. That's not to say I feel
>>>> immune with this system as I don't, but if I disconnect anything it gets
>>>> grounded.
>>>>
>>>> 4th photo down on http://www.rogerhalstead.com/ham_files/cablebox.htm
>>>> shows the initial entrance box. It's been replaced with a larger box,
>>>> more cables, more polyphasers and more grounds. The bare #2 copper
>>>> ground line on the far right caries through to the equipment inside the
>>>> house.
>>>>
>>>> 73
>>>>
>>>> Roger (K8RI)
>>>>
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>
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