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70cm UHF Repeater Build Up, Update 1

So after a few weeks of doing some research, and joining a few yahoo groups to help in the research, I have some progress. Since I can't see spending money on something that locks me into 1 option I am looking for a repeater controller that has more then I really need right now. I am looking at the NHRC-4 it has room for two repeaters, or a repeater and a link, DTMF programming, a digital switch and some other stuff, along with the required IDing. It comes either as a kit, or pre-assembled. I think I am going to get it pre-assembled. I will have enough to do with all the other bits, and the price is not too bad either.
 
For the radio(s) I am still up in the air. Using HTs are pretty much out, while they are cheap, they are cheap. The HTs have little to no shielding, little to no heat sinking, and nowhere near designed for near 100% duty cycle. Sure they would work well if I just wanted to do a proof of concept type thing so I could say I built one, but I want to be able to use this, and have others use it as well. Eventually I would like to see it sit on a small tower with maybe 75-100W output, and have a 10M link, but we will see how it goes. So that leaves me to linking two similar radios, like a Kenwood TK-805D, or just getting a Kenwood TKR-820, which is a desktop repeater with about 5W at 100% duty cycle. Currently I am leaning this way, as the TKR is meant to be a repeater, and can handle 100% duty cycle. if you haven't notices "100% duty cycle" comes up a lot. Well... look at it this way, if 2-3 hams are using a repeater their radios only get used about 33% of the time, assuming they all talk for about the same time. That leave time for the radio to cool down, BUT the repeater is running for all three, and gets no time to cool. Equipment not rated for this use will burn up in no time. look at the TKR-820 as an example, it is rated for 20W at 50%, and only 5W at 100%. Now you have to decide what duty cycle you will use, but for my initial setup I think I can get away with 10-15W and not have an issue for now. When it sees more use and longer QSOs I will have to look for a separate power amp for it.
 
Well that is where I am with this project, maybe I'll be on the air before 2013, but not likely.

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