View Single Post
  #4   Report Post  
Old October 2nd 05, 05:42 PM
Dave
 
Posts: n/a
Default

what sleeve and what coax? you asked about Er for tubing and didn't mention
any other components.

"David" wrote in message
...
OK, so the electrical wavelength of the tube will only be effected by the
dielectric material and it does not make any difference how large the gap
is between the Sleeve and the Coax ?

The frequency of operation is 920 MHz.

Do you happen to know what the covering is made of on the outer sheath of
RG174 ? The cable I have has a stranded inner core and seems to have a
PFTE dielectric. (Doesn't melt at all when soldering so I assume this is
what it is).



Reg Edwards wrote:
"David" wrote

Does anyone know where I can find Er tables for various type and


diameter

of metal tubing so I can calculate Velocity coefficient Vp ?


=====================================
The velocity factor of any conductor, including tubes, depends only on
what surrounds it.

If the surroundings are air, which is mainly oxygen and nitrogen, then
the VF = 1.00, equivalent, in metric units, to a velocity of 300
metres per micro-second. Or in ancient, old-fashioned units, it is the
far-less-convenient 669600000 miles per hour, give or take a few
100,000 miles. Who cares?
---
Reg.