Quarter wave and counterpoise? With antennas "short" generally equates with "sucks". I have seen a counterpoise add 6db even to a helical "ducky". On Aug 3, 2016 10:58 PM, "Neil" wrote: > Hi all, > > I built a quick device for a friend that lets a receptionist send > messages from a PC to a desktop display device, and vice-versa with a > handful of canned responses. The PC side uses VB to serial (via USB), > to a USB-to-serial interface, then a 433 Mhz serial module, through an > IPEX-to-RP-SMA interface, to a short whip antenna. The desktop display > device also has the same 433 Mhz serial module (controlled by an > Arduino), to the same IPEX-to-RP-SMA interface cable, then to an > identical whip antenna. > > I'm not getting the range necessary... I'm getting 35-ish feet indoors > (through one wall), and need about 100 feet indoors (in an office > through a glass wall). I've tried a 433 Mhz PCB antenna, but that got > me less distance than the whip antennas. And the whip antennas are > listed as being for 433 Mhz. > > Any clues on how to get better distance? I'm looking for 433Mhz > amplifiers, but they're a bit pricey. I'm short on time, so hoping to > find a ready-made solution (if an amp is necessary), rather than having > to build one. > > Cheers, > -Neil. > > > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .