The attenuation curves generally follow a straight line when drawn on log-log graph paper.   The slope is such that a coax with 2dB at 50Mhz will be 0.8 at 10Mhz.   Most coaxes have about the same slope.   What causes this attenuation is mostly the "skin effect" on the center conductor.   So, one need only look at the same freq when comparing attenuations when selecting which coax you're planning to use from under the shack table (not strictly true, but close enough for "goverment" work! :-) ).   Voltage ratings: note that foam dielectric cannot take as much voltage as solid dielectric.

73 de WA2ISE

Text and layout for the tables above is © Copyright 1997 Robert Casey WA2ISE   Contact via the email address available at http://www.qrz.com/~WA2ISE

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The information below was collected by WA6ILQ:
See the note at the bottom regarding Heliax velocity.

Coax Style	DB Loss per 100 feet Frequency in Mhz			Velocity	O.D.	Shield	Notes
	147	444	903
Andrews FSJ1-50	2.25	4	6.18		n/a	100%	solid copper jacket   1/4 inch Superflex
Andrews FSJ4-50B	1.275	2.4	3.37		n/a	100%	solid copper jacket   1/2 inch Superflex
Andrews LDF2-50	1.275	2.3	3.31	.88	n/a	100%	solid copper jacket   3/8 inch Heliax
Andrews LDF4-50A	0.83	1.5	2.2	.88	n/a	100%	solid copper jacket   1/2 inch Heliax
Andrews LDF5-50A	0.455	0.83	1.23	.88	n/a	100%	solid copper jacket   7/8 inch Heliax
Andrews LDF6-50	0.34	0.615	0.91	.88	n/a	100%	solid copper jacket   1-1/4 inch Heliax
Andrews LDF7-50	0.25	0.46	0.72	.88	1.98	100%	solid copper jacket   1-5/8 inch Heliax
Times Microwave LMR-200	4	7	10		0.195	100%	Not recommended for duplex use
Times Microwave LMR-400	1.5	2.7	3.9	.85	0.425	100%	Not recommended for duplex use
Times Microwave LMR-600	1	1.7	2.5	.85	0.59	100%	Not recommended for duplex use
Times Microwave LMR-900	0.7	1.2	1.7		0.875	100%	Not recommended for duplex use
Times Microwave LMR-1200	0.5	0.9	11.3		1.25	100%	Not recommended for duplex use
Belden 8214 (RG8/U type)	2.25	4.5	6.7		0.403	97%	n/a
Belden 8216 (RG174/U type)	10.5	20.5	31		0.101	90%	n/a
Belden 8240 (RG58/U type)	5.65	10.7	16		0.193	95%	n/a
Belden 8259 (RG58A/U type)	6.1	12.5	20		0.193	95%	n/a
Belden 8267 (RG213/U type)	2.35	4.6	7.6		0.405	97%	n/a
Belden 8268 (RG214/U type)	2.35	5.1	7.7		0.425	97%	double silver shield
Belden 9258 (RG8/X type)	4.55	8.5	12.8		0.242	95%	n/a
Belden 9273 (RG223/U type)	5	9.4	13.8		0.212	95%	double silver shield
Belden 9913 (RG8 type)	1.55	2.9	4.2		0.405	100%	Braid shield over foil shield, not recommended for duplex use
Belden 9914 (RG8/U type)	2	3	5.7		0.403	100%	braid shield over foil shield
Belden 84142 (RG142 type)	4.75	8.8	12.5		0.195	98%	brown FEP jacket - double silver shield

The table above gives 0.88 as the velocity for all LDF series cables. I have seen one book that mentions only 1/2 inch and 7/8 inch and gives 0.81 for a velocity factor. Not havaing the equipment to measure it myself I have no idea as to which is correct.

Most of us don't think of it, but the outer jacket of most feedline cabling is flammable, and this factor can influence how you run the cabling and what cable you chose to run - some types are available with a teflon outer jacket, many are not.   This flammability aspect was brought home to me by a recent email pointing me at these two web pages:
Fire at the tower, by John White, K7RUN,
and at Wanted Poster - Arsonist
The first article is WELL WORTH READING, and does not mention the fact that many cable jacket materials give off toxic fumes while burning.

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Hand-coded HTML © Copyright 2005 and date of last update by Mike Morris WA6ILQ
Original page created 01-Dec-2004 by WA6ILQ from WA2ISE's saved page layout.
Page updated - added the lower table 12-2006 by WA6ILQ