[Elecraft] Cable X-Perts RG-8 vs Davis Bury Flex

[Don Wilhelm]

Jeff,

My own 'rule of thumb' is that 2 dB less loss in your coax is worth it, 
1 dB is not worth the money or trouble.

You will have to figure the relative loss for your highest band of 
operation, your cable length, and your SWR on the line.  All of those 
factors should be considered.

In other words, the worst RG-8 listed in the ARRL Antenna Book has a 
loss of 1.9 dB per 100 feet at 100 MHz - so your 50 foot length will 
have only 0.85 dB loss at 100 MHz (less at lower frequencies).  The loss 
will not go below 0.0 dB in any case, so by my 1 dB 'rule', it is not 
worth replacing.

OTOH, if you are running that RG-8 at a 5:1 SWR, The loss will increase 
by 0.7 dB which gives you a total loss of 1.5 dB at 100 MHz - still not 
enough to be gained to make it worthwhile for me, especailly if used on 
HF.  YMMV.

Note: I have a 150 foot run of coax before I reach the antenna field or 
go up a tower or mast, so it only takes a small reduction in loss at 
that length to make me think about a change, but for a 50 foot run, I 
would not bother.

73,
Don W3FPR

J S wrote:
> I've read that Davis Bury Flex is very good (low loss) coax. I have
> Cable X-Perts RG-8 (50 feet of it) as my feedline right now.  Is it
> worth my time and $ making a change to Davis Bury Flex or something
> similar?
> 
> Jeff
> K6ATT