[TenTec] [Fwd: Line Isolator Balun (sorta) question.]

[Dr. Gerald N. Johnson]

First thing you need is good short ground connections between units, 
often the coax performs that. If the equipment is fully shielded, there 
shouldn't be any RF on the outside of the coax, providing the shield 
braids are properly connected in the connectors and the connector shells 
(UHF) are tight. I prefer other connectors which have springy shield 
connections like BNC, C, or N. Coax cable with lots of braid (not like 
that sold in Radio Shack stores) is of benefit in keeping RF IN the coax.

On 8/6/2010 1:25 PM, Rick - NJ0IP / DJ0IP wrote:
> I have had different experience, Jerry.
>
> Living in Europe, I often found myself with the ham shack on the 2nd or 3rd
> floor and occasionally even higher.
> Obtaining a good ground is a challenge under these conditions.
>
> Running my Omni V, VI, and VI+ into a linear, I sometimes found I would have
> certain bands where I couldn't run more than about 300w before the circuit
> breaker on the 961 blew.  Usually it was 15m but sometimes even 40m.
>
> I found by inserting a line isolator (mine was from Radio Works) between the
> transceiver and the linear, it always cured this problem.
>
> A few times I had my shack at ground level or in the basement and had a
> short lead to a good ground.
> I never encountered this problem under these good conditions.
>
> My take out of that was always have one of these line isolators with me on
> my portable operations because you never know what kind of ground you will
> get at the portable QTH.
>
> 73
> Rick
>
73, Jerry, K0CQ