Here is yet another approach from back in the '70s: The 146.94 repeater in Ft Worth was located on a 1000 ft tower on the east side of the city. It utilized a solid state converter for 2 meters down to the 10 meter band where plenty of low band receivers would work. I think it used a piece of RG-58 to route the 10 meter signal to the bottom of the tower. The transmitter was located at the 500 ft level and several transmitters were utilized. a separate 145.76 repeater was implemented from this same receive antenna with a directional antenna to serve Ft Worth only. Receivers for 146.34, 146.94, 146.16 and maybe 146.76 were all connected to the 10 meter down converter output.
Receiver outputs were all routed to 440 transmitters and receivers to allow interconnect at a trustee's home. I once saw this system work a skip situation with the 146.94 repeater in Little Rock Arkansas where a station on the Ft Worth repeater was repeated on the Little Rock repeater and a station on the Little Rock repeater was repeated on the Ft Worth repeater. Granted when the Little Rock repeater stood down, the Ft Worth repeater would howl, but as soon as a signal appeared on 146.94 the incoming signal would override the local .94 output and through the 440 link it was repeated back on the local .94 transmitter. I never knew how much isolation this represented, but it was really a nice set up for a repeater system. Alas - it all went away when the 1000 ft tower was removed. I worked this repeater regularly from my mobile Progress Line 60 watt radio in Greenville, TX - 90 miles away. 73 - Jim W5ZIT --- On Wed, 12/17/08, kb5vjy <[email protected]> wrote: From: kb5vjy <[email protected]> Subject: [Repeater-Builder] Yet Another split antenna Question To: [email protected] Date: Wednesday, December 17, 2008, 11:04 PM Folks, I have read just about every split antenna post that I can find.. I hate to be a "yet another" poster but here is my situation. I just want to know if it is do able. And what problems I might run into. After months of waiting, I have been issued a repeater pair of 147.255 for a long range 2m repeater that will be installed. This is my first 2m repeater, but I do have 3 70cm repeaters (all Mastr II's).. My situation is the following: I have a Mastr II Station 100w Cont. Duty PA for the project... I still have to order the xtals. I will run a PL as needed on 127.3. The controller will be a CAT (version unsure of) I have a 2000' broadcast tower with a platform at 1300' and another at 1000'. There is a DB 224 mounted under the 1300' and one under the 1000' platform with a section of 7/8 feedline running from the top platform and the bottom platform. There is a full rack size NEMA 12 enclosure on the 1300' platform. After Feb '09 there will be NO VHF transmitting equipment on this tower at all. The closest transmitter is 6 miles away. What I would like to do, is mount the radio in the enclosure at the top platform. Use the top DB 224 for the Receive antenna, and the 1000' DB 224 for the Transmit antenna. What are the problems that I will run into with this situation, and should I look for some type of filter for the receiver. I do plan on putting an APRS Digi at 1300' as well moving one of my 70cm repeaters to the same platform some time early next year. Any comments would be helpful. Thanks.. 73 de Joe KB5VJY.... Sorry.. RTTY dayz!
