Skipp, I agree with nearly every point you made, having had experience with both the Kenwood and Hamtronics repeaters. However, Hamtronics and similar repeaters have one serious deficiency: A total lack of PA protection against high SWR due to antenna or feedline problems. In addition, the Hamtronics PAs have no active power control circuitry; if the supply voltage goes up, the output power goes up, and vice-versa. The Kenwood TKR-x50 repeaters, on the other hand, have both active power control and high SWR protection built-in.
I have a Hamtronics REP-200 repeater in service right now on 224.500 MHz, and I took the precaution of hanging a single ferrite isolator on its TX output to protect the very simple 15 watt PA. So far, so good... 73, Eric Lemmon WB6FLY -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of skipp025 Sent: Tuesday, March 02, 2010 9:35 AM To: [email protected] Subject: [Repeater-Builder] Re: Hamtronics versus Commercial (Kenwood) Repeater Selection A Hamtronics versus a Kenwood Repeater... > If you are considering purchasing the Hamtronics REP-200 > repeater, I would spend my money on a Kenwood TKR750/850 > series repeater. They are about the same price, but the > Kenwood is a much better built piece of equipment and has > a decent built-in controller for basic operation. As a huge and long time fan of Hamtronics gear and of course a full Kenwood Dealer and Service Station... I have to say I'm in a corner regarding the above statements... Both complete Repeaters are in the same price range and of course the Kenwood is a commercial quality/spec unit. But the Hamtronics unit is also quite usable, has more desired Amateur Radio Operational features (because of the internal controller). The Hamtronics Repeater in basic form is lower in transmit power output and the chassis is not as rugged (thick metal chassis parts). But there's nothing wrong with the supplied chassis of the Hamtronics Repeater if you buy the pre-made complete repeater versus installing transmit and receive modules in your own box of your selected size and material(s). Unless you install an additional external repeater controller onto the Kenwood Repeater... you don't get an Auto-patch (telephone interconnect), the ability to command CTCSS (PL) and Carrier Squelch operation on/off and a number of other "bells and whistles" you could research by inventorying the feature set page of the Hamtronics Repeater Controller Manual (on their web page). > If you were looking to buy just the individual pieces from > Hamtronics and put your own repeater chassis together, I > would prefer to use just about any commercial equipment > instead of those pieces. ... which shows a fairly obvious bias against Hamtronics Equipment for what-ever reason good or bad. There's nothing wrong with current Hamtronics, Hi-Pro and similar products if you understand what you get when you buy them. They tend to be very decent performers and in the case of the Hamtronics unit... probably also FCC Type Accepted. > I am not sure what features you are looking for in the > controller but there is a large amount of support available > in the amateur community for Arcom, NHRC, CAT, ICS, and > Link-Comm controllers. The Pacific Research Controller > does not seem to be used much in our area but it looks > like it will do most things a person would need. So will the Hamtronics COR-5 Repeater Controller > Good luck with your project. I suspect the selection of radio products would obviously come down to motivation and money. If you bought a ready to rock-and-roll Kenwood TKR-850 Repeater (from me :-) you'd be pretty much in a plug & play situation once you had a duplexer & antenna scheme in place. You could then or later install an external repeater controller onto the TKR-850 if you needed additional operational features not available with the "stock TKR-850 repeater controller". If you were interested in a converted surplus radio package, you could save a bit of money and probably have to get more into the technical details of the equipment while trying to get it on the air. There are also a fairly large number of usable repeaters made from surplus Mobile Radios connected "back to back" with basic logic and audio cables. You could also go with a more modular and hand constructed Hamtronics, Hi-Pro Modular type of repeater project, which is a favorite topic of mine. You will learn a lot more about both repeater and radio operation if you construct your own repeater. There is a serious glut of cheap, high quality surplus radio gear available at flea markets and Ebay... so all bets are off on pricing on that type of gear... you might even find people willing to donate equipment for little or nothing. When 224 MHz band repeater operation is desired... there is less plug and play gear available, so cases like building a project using Hamtronics and Converted Surplus gear should be a lot more cost effective. Indeed I've done many a project from Hamtronics and Hi-Pro Modules (as well as a number of other brands) and of course have provided examples of these projects in photos available in the Group Photos Section: http://groups.yahoo.com/group/Repeater-Builder/photos/album/1157128983/pic/l ist <http://groups.yahoo.com/group/Repeater-Builder/photos/album/1157128983/pic/ list> You could easily duplicate the above mentioned project in the UHF 445 MHz Amateur Band with great results. Keep in mind you have to do all the hardware (chassis holes, wiring, mounting of modules, testing... etc) but if you're into that type of building there's a lot of fun and knowledge to be had... So, I'm an advocate of both the buy-it or build it repeater method. You have to figure out how much time, money and resources you want or are willing to apply toward getting things done (a repeater on the air). And of course "Repeaters are like opinions..." or is it the converse? cheers, skipp skipp025 at yahoo.com > > "k9bf" <k9bf@> wrote: > > Hi all. > > I am thinking about implementing the above products into > > a repeater. I would like some comments from those that > > have experience with any of them. Also, does anyone have > > any for sale? This is for a UHF machine and would use the > > newer Hamtronics components. > > Thanks and 73 > > Ben K9BF
