Yes a very negative effect and not a good idea.. If you look in the
history of this NG you will see some numbers about minimum separation
distance from other metal.

If you really want to run a balanced feeder you can use two pieces of
coax with the shields connected at each end. The Z will be twice that of
the original coax. (I use this as a Q section on 20m feeding a loop of
about 170 ohms) Dunno about losses in this case (which open wire feeder
are great for reducing) and of course the Z is going to be kind of lower
than 450r.

Cheers Bob VK2YQA

jimbo wrote:


Thanks for the replies. The ladder line would be used when the other
lines were not being used. Does the proximity of other unpowered lines
affect the ladder line operation for receive and transmit?

Thanks, jimbo