VHF_SWRA Pocket-Size, Direct-Reading VHF SWR Meter This easy-to-build LED bargraph SWR meter goes with you anywhere. By Bill VanRemmen, KA2WFJ Here’s a little SWR indicator that uses an LED array as the readout. Its microstripline directional coupler feeds a sample of the feed-line’s forward and reflected waves to an LM3914 dot/bar display driver. [1] The driver lights an LED whose physical position in the array is proportional to the ratio of the forward and reflected signals. The uppermost LED lights when the SWR is 3:1 or higher, improving resolution in the lower SWR range. Microstripline design allows this circuit to be used at VHF and possibly higher. General Description This metering circuit uses an LM3914 (see Figure 1) with the forward voltage applied to the top of its internal resistiv……