Re: [Repeater-Builder] Diversity FM reception
Feeding 2 separate V H antennas in phase yields 45 degree polarization. If one antenna is fed 90 degrees lead or lag, then you have RH or LH CP. --Don-- W8DPK larynl2 wrote: ... Years ago before CP antennas were commonly available, FM stations would feed two separate antennas on the tower. One was H, the other V. Was that then 45 degree polarization?? ... Laryn K8TVZ
Re: [Repeater-Builder] Manual needed Motorola S-1320A Signal Generator
Here is a link to the S-1320A service manual: http://mcarcoh.org/S1318-19-20-21-29 Signal Generator.pdf It's a pretty large file, about 16MB, but it's very high resolution. I'll leave it on the site for a few weeks. 73, --Don-- W8DPK ,___
[Repeater-Builder] Weatherproofing A449-6 Gamma Match
Our club 2M repeater uses Cushcraft A449-6 yagi antennas at the each end of the 440 MHz links to the 3 remote receive sites. One of the links occasionally fails during rainy or icy weather. I've always been concerned that the gamma match (Cushcraft calls it a Reddi-Match) is out there in the weather with no protection. I've been considering using ScotchKote on the assembly to weatherproof it. Will ScotchKote affect the SWR or performance at 440 MHz? Is there a better method? Thanks and 73 --Don-- W8DPK
[Repeater-Builder] Side-mounted DB-224 performance
Our club has permission to mount our brand-new DB-224E on the side of the local hospital's tower, about halfway up (90'). We want maximum signal to the north-east, so will be mounting the antenna on the NE leg of the tower, with all 4 elements on the NE side of the mast. Is it necessary to use a stand-off bracket? Or would it be OK to mount the mast right next to the tower leg using the bracket(s) that came with the antenna? I don't care about performance to the south-west; actually a null to the SW would be good to minimize interference from a co-channel system only 100 miles away. 73, --Don-- W8DPK
