The device for measuring the current or emf is connected within the circuit of the thermocouple. It measures the amount of emf flowing through the circuit due to the two junctions of the two dissimilar metals maintained at different temperatures. In figure 2 the two junctions of the thermocouple and the device used for measurement of emf (potentiometer) are shown.
I think that this is what advertisers are shooting for when they pay the big price to get their ads up there. Regular billboards are just as effective as ever, even though there are now digital billboards being made that can have multiple ads on them and switch between them every few seconds.
How much does a billboard cost? 1  Billboard advertising costs can be different depending on the location of the billboard. 2  The price for electronic billboards can cost anywhere from $1,200 to $5,000. 3  One of the companies that offers billboard advertising is Blue Line Media.