Hi Joe, I have a large number of the Securicor, Intek 220MHz ACSB trunking combiners removed from service here on the West Coast (California). T'was at one time quite the build-out... going from Texas up through Alaska.
At first glance it appears least one of almost every antenna combiner manufacture produced their own version of the 5 channel combiners for the various incarnations of 220MHz Trunking. However, there are/were other size trunking systems... I have also seen and worked with two and three channel TX combiners. So I have Wacom, Cellwave, Aerial Systems, RJ, Telewave, Sinclair and a few other custom made configurations here. And there are different variations of combiner systems made by the various manufactures. It's very interesting to see how different people accomplished the same task with fairly similar and different hardware layouts. So what is most practical to do with what you have depends on what specific hardware you received. In most cases it's well worth your time to try and track this stuff down... lots of the hardware found in the combiner translates to use in other applications. Specific to the Cellwave hardware you have... depends on what you have. Some of the Cavities are set for pre-selection insertion loss, some are set for one frequency notch. Some cavities have semi fixed loops/probes that are hard to work with... and then there's the easily adjusted bottles. I measured and made actual performance graphs for the Cellwave version... so email me direct if you would like to talk more about it off the list. I'm using a number of the original as-built TX Combiners at various mountain top sites. They simply needed minor modifications and re-tuning. Some of the combiners racks (like a number of the Cellwave units I have) include receiver pre-selection. In many cases the receiver pre-selection will work for low power systems but is really not enough for 2 or more high powered transmitters in the typical close spaced Amateur Ap. The Aerial Systems Square Cavities mentioned in dcflux's post are really, really nice units with relatively much high Q compared to slightly smaller round cavities. But they are cumbersome to mount if you don't have the original mfgrs rack rails. I can post information and hints here if people are interested but it's probably more practical to yak off the list. Please feel free to (send food) email me direct. cheers, skipp skipp025 at yahoo.com > Joe <k1ike_m...@...> wrote: > I have an opportunity to get a combiner/filter panel from a > 220-222Mhz ACSSB system that was abandoned years ago. Has > anyone experimented with making a 222Mhz duplexer out of > the parts in the Celwave rack that was used in this system? > 73, Joe, K1ike
