[TowerTalk] Orion 2800 Rotator Cable Replacement

[john at kk9a.com]

The link may work better without the sentence period.  
http://www.cmewire.com/catalog/sec02-bcc/bcc-01.pdf

KK9A

Quoting john at kk9a.com:

> An alternative to the stretching exercise would be to purchase hard  
> drawn copper wire, here are the specifications:
> http://www.cmewire.com/catalog/sec02-bcc/bcc-01.pdf.  BTW, I used to  
> purchase copperweld however it held so terribly at P40A that I quite  
> using it.
>
> John KK9A
>
>
>
> Bob Shohet, KQ2M wrote
>
> Hi Jim,
>
> ”A major advantage of using stretched wire is that un-stretched copper
> will stretch under tension over years. Before changing to stretched
> wire,”
>
> I have seen you mention this a number of times in the past and I  
> have been meaning to ask you some questions about it.
>
> My non-engineering understanding of wires and stretch is that a  
> given wire after being subject to variable strength forces over a  
> given period of time, will stretch only so far before it breaks.   
> Assuming that that is conceptually correct, let’s say that we have  
> two wires – Wire A and Wire B.  Wire A has been pre-stretched before  
> being put up and is now compared against Wire B which has just been  
> put up without being pre-stretched
>
> Now we subject both wires to the same forces over the same period of  
> time.  I would expect that going forward Wire A will not stretch as  
> far as Wire B, but is more likely to break and break sooner under  
> significant force than Wire B because it has already been  
> pre-stretched.  Wouldn’t this be correct?
>
> If this is not correct, can you please explain why?
>
> Tnx & 73
>
> Bob  KQ2M