[TenTec] OT: Openwire/Window Line and Bad Wx

Rick - DJ0IP / NJ0IP Rick at DJ0IP.de
Tue Jul 30 16:19:49 EDT 2013


Bob, that only works with the true link-coupled tuners, such as Johnson
Viking, or Annecke.
But most people don't have those, so they're hosed.

I wanted to post how I do it but can't find pictures.
It's late here, so I'll search for pictures tomorrow.
Annecke used to sell some outstanding solutions to the grounding problems.
I still own them, but unfortunately you can't buy them new anymore.

73
Rick, DJ0IP

-----Original Message-----
From: TenTec [mailto:tentec-bounces at contesting.com] On Behalf Of Bob McGraw
- K4TAX
Sent: Tuesday, July 30, 2013 9:05 PM
To: Discussion of Ten-Tec Equipment
Subject: Re: [TenTec] OT: Openwire/Window Line and Bad Wx

Further to this, a properly designed balanced feed system should balance the
line to ground as opposed to just a balanced output or being balanced above
ground.  Being properly designed, be it a balun or balanced tuner, it should
provide a path to ground.  In effect the secondary at the center tap, should
go to ground and not be floating.  Hence no further steps required to bleed
off static build-up from wind, snow and etc.

On this point, any degree of unbalance in the system can be measured as
current in the ground path between the CT of the balanced network and
station ground.  Thus little to no current indicates a good balanced system.

More current indicates some degree of unbalance with larger current values
indicating greater degrees of unbalance.

73
Bob, K4TAX






----- Original Message ----- 
From: "Bob McGraw - K4TAX" <RMcGraw at Blomand.net>
To: "Discussion of Ten-Tec Equipment" <tentec at contesting.com>
Sent: Tuesday, July 30, 2013 12:10 PM
Subject: Re: [TenTec] OT: Openwire/Window Line and Bad Wx


> Yes, but lightning is not DC.  It is a series of short duration pulses 
> resembling AC and should be treated accordingly with little to no 
> inductance in the path.  Thus any inductance in line would actually 
> prevent the energy from going to ground.
>
> For lightning protection on balanced feed systems, see The Wireman model 
> #878 as one good example.   Just about every series fed broadcast tower 
> uses an "arc gap" method for that purpose.  I find that a pair of small 
> engine non resistive sparkplugs mounted on suitable hardware which is 
> adequately grounded does an excellent job and with no issues at legal PEP 
> power.
>
> The old knife switch approach is OK........... if one remembers to put the

> switch in the proper position when lightning is around or the station goes

> QRT.
>
>
> 73
> Bob, K4TAX
>
>
> ----- Original Message ----- 
> From: "Robert Arenella" <rja12 at comcast.net>
> To: "Discussion of Ten-Tec Equipment" <tentec at contesting.com>
> Sent: Tuesday, July 30, 2013 8:01 AM
> Subject: Re: [TenTec] OT: Openwire/Window Line and Bad Wx
>
>
>>
>>> On 7/29/2013 11:31 PM, Richards wrote:
>>>
>>>  > A second question is what lightning protection devices are preferred
>>>  > for securing open transmission line?
>>>  >
>>>  > ===============  K8JHR  ================
>>>
>>> I'm not sure what is "preferred", but what I use is a large DPDT knife
>>> switch, one side to the tuner, the other position to ground.
>>>
>>> Although I don't use one, there is always the ever-popular dual spark
>>> gap as shown in the old (and maybe newer?) Handbooks.
>>>
>>> Finally, for static mitigation there is the high value resistor from
>>> each open wire conductor to ground.
>>>
>>> 73,
>>> Carter   K8VT
>>>
>>>
>>> _______________________________________________
>>> TenTec mailing list
>>> TenTec at contesting.com
>>> http://lists.contesting.com/mailman/listinfo/tentec
>>>
>>
>> Another option is to use a pair of plate chokes from each half of the 
>> feedline to ground.  I have a friend up in NH using this setup.  Keeps 
>> the antenna & feedline DC grounded.  Lightning isn't his big problem, 
>> static electricity generated by blowing snow was creating havoc at his 
>> station. The chokes solved the problem.
>>
>> 73 de bob,
>> N2OAM
>> _______________________________________________
>> TenTec mailing list
>> TenTec at contesting.com
>> http://lists.contesting.com/mailman/listinfo/tentec
>>
>
>
> _______________________________________________
> TenTec mailing list
> TenTec at contesting.com
> http://lists.contesting.com/mailman/listinfo/tentec
> 


_______________________________________________
TenTec mailing list
TenTec at contesting.com
http://lists.contesting.com/mailman/listinfo/tentec



More information about the TenTec mailing list