Index of refraction is pretty constant with frequency, it is roughly equivalent to dielectric constant and permittivity. But angle of refraction does change with frequency. Snell’s law.
From: Adam Moffett Sent: Sunday, January 22, 2017 10:33 AM To: [email protected] Subject: Re: [AFMUG] PTP450 SNMP Miles 6205ft / 126 = 49ft I remembered the right multiplier....but apparently I made up the reason. The multiplier was different for 900mhz. I don't remember about 2.4ghz. Correct me if I'm wrong, but doesn't the index of refraction vary with wavelength? Isn't that why a prism makes a rainbow? If so, then the speed of 5.8ghz microwave through air would be different than simply "speed of light". Is it still close enough for these girls you mention? ------ Original Message ------ From: "Chuck McCown" <[email protected]> To: [email protected] Sent: 1/20/2017 11:51:09 PM Subject: Re: [AFMUG] PTP450 SNMP Miles OK, round trip would be 6205 x 2 or 12410 nS in a vacuum. But it is a bit slower in air. Close enough for the girls we go with. From: Steve Utick Sent: Friday, January 20, 2017 9:45 PM To: [email protected] Subject: Re: [AFMUG] PTP450 SNMP Miles For reference, I checked a PTP450 radio here. It shows An Air Delay of 126 bits, 12625 ns and 1.175 miles (6205 feet) On Fri, Jan 20, 2017 at 8:11 PM, Adam Moffett <[email protected]> wrote: I don't know if this is still true, but it used to be that air delay was a count of 10 nanosecond intervals, and if you multiplied by 49 feet you'd get the actual range. 49 ft/10ns being the speed of the signal through the medium. ------ Original Message ------ From: "Steve Utick" <[email protected]> To: [email protected] Sent: 1/20/2017 6:09:23 PM Subject: Re: [AFMUG] PTP450 SNMP Miles Air Delay on the PTP450 is at: .1.3.6.1.4.1.161.19.3.1.4.1.24.2 The current round trip air delay in bits measured between the AP and SM. On Fri, Jan 20, 2017 at 8:19 AM, Matt <[email protected]> wrote: Anyone know how to pull link miles from a PTP450 link master using SNMP?
