Labels:bulletin board | reckoner | scauper | sky OCR: (A) BULB ConneCtor CONNECTOR SHIELD BOX (B) ANTENNA LINE ANY XMtr LINE JNE LENGTH /8 Figure 1. Use of lamp bulbs as ammeters. (A) Use as wide-band RF ammeter Estimate current by brightness. Or. place second bulb with known current from battery rheostat and ammeter as close as possible. adjusting current for equal brightness. The RMS current is the same as the ammeter reading. Two bulbs separated by 1/4 wavelength make SWR indicator. Equal brightness is 1:1 SWR unless line length accidentally such as to give a false equality If the relative brightness changes on moving the 1/8-wave section to the transmitter end, the new relative brightness is the correct indication.
