oh, one very important item I forgot to add......the termination at both
ends of your jumpers will be ABSOLUTELY critical as to how well your
overall shielding effectiveness will be. You have to make sure that the
connectors you use are of good quality and are properly terminated. The
best quality shielded cables will be rendered near useless when it comes
to SE if the shields are not properly bonded to the outer shell of the
connectors at both ends.
Gedas, W8BYA
Gallery at http://w8bya.com
Light travels faster than sound....
This is why some people appear bright until you hear them speak.
On 9/4/2019 3:31 PM, Gedas wrote:
It will depend on who makes the cables you are comparing. If both are
M17 rated then both should be double shielded and use silver coated
copper conductors which is good but some manufactures may use 95%
braid coverage while some may use less. Some may use 95% for both
shields others may use 95% for the outer and less for the inner. Also
the angle of the weave also affects the shielding effectiveness. This
SE will also vary with frequency. But in general, esp for HF use, you
will find both to have similar shielding performance as long as you
stick to a known trusted & respected name brand. Also keep in mind the
dielectrics are totally different between the two.
Gedas, W8BYA
Gallery at http://w8bya.com
Light travels faster than sound....
This is why some people appear bright until you hear them speak.
On 9/4/2019 2:54 PM, Stig Lindblom wrote:
Gents;
We are rebuilding a contest station operating room (HS0ZAR@HS0ZGD) and
need to do a lot
of new jumpers.
Ref. advise below from K9YC (tnx) we will use RG400 (or similar) for
short jumpers.
Considering to use RG214 (double shield) for longer jumpers, and for
coax-stubs as well.
How is the measured, or experienced, shielding of RG214 compared to the
RG400 ?
73 de Stig
LA7JO _ HS0ZGD
On 8/6/2019 6:50 AM, Gedas wrote:
And. the conductors are Silver plated, copper clad steel.
------------------
Clarification for other readers. The center of RG142 is silver coated
copper coated steel, the center of RG400 is stranded silver-coated
copper. Both have double silver-coated copper braid shields.
Loss is about the same as RG58 -- in other words, fairly high. The
principal virtue of these cables is their superior SHIELDING, which is a
LOT better than most braided coax. You only want to use this stuff for
short jumpers.
I've been happy with at least two purchases of Harbour Industries RG400
that I've found on ebay from a US vendor. Harbour Industries is based
in VT, and has a presence across the border in QC. NA6O was happy with
the RG400 he bought from China.
73, Jim K9YC
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