User:Netshine2/sandbox

stripline

Characteristic Impedance
An accurate closed form equation for the characteristic impedance of a stripline with a centered conductor has been reported as

$$\begin{align} Z_{stripline} &= \frac{30\pi}{\sqrt{E_r}}\frac{1-T}{W_{eff}+C_f} \\ C_f &= \frac{2}{\pi}log\biggr(\frac{1}{1-T}+1\biggr)-\frac{T}{\pi}log\biggr(\frac{1}{(1-T)^2}-1\biggr) \\ \end{align}$$

Where:

$$\begin{align} W_{eff} &= \begin{cases} W-\frac{(0.35-W)^2}{1+12T}, & W<0.35 \\ W, & W \ge 0.35 \end{cases} \\ T &= \frac{t}{h} \\ W &= \frac{w}{h} \\ w &= \text{width of the stripline conductor} \\ t &= \text{thickness of the stripline conductor} \\ h &= \text{thickness of the substrate from the top ground plate to the bottom ground plate} \\ E_r &= \text{dielectric constant of the substrate dielectric material} \end{align}$$

Note that when the conductor thickness is small, T< .05 and T< 0.025.

Mount Elden Contemporary History

Contemporary history
John Elden, the settler for whom Mount Elden bears its name, settled at the base of what is today Mount Elden in 1877 to raise sheep near a natural spring, now referred to as Elden Strings. The home-site today lies within the Kaibab National Forest and bears a National Forest historical marker just north of the City of Flagstaff, Arizona, pictured to the right.

John Elden earned notoriety when according to legend his six year old son, Little John Elden, was felled by a gunshot, purportedly by a disgruntled stranger named Bob Roberts attempting to water his horse at the spring but was turned away by Mrs. Elden. A citizens posse was formed to track down and catch Roberts, and Roberts was killed shortly afterwards under unknown circumstances. Elden then abandoned the home-site and moved his family to California to start a dairy business. However, none of the legendary story regarding the murder of Little John, the murder of Roberts, or the citizen's posse any any basis in historical fact in that no valid historical records were ever found, although the Little John grave site today remains a historical marker next to the home-site.