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eHam Forums => Mobile Ham => Topic started by: N4ZYV on September 26, 2003, 05:19:15 PM



Title: What is the best mobile tuner?
Post by: N4ZYV on September 26, 2003, 05:19:15 PM
Anyone here like to give opinons? Sort of like asking who wants to be a millionaire, huh?
I'm going to set up my little pickup for HF. I'll be using a 102" whip to start with. Is there a mobile tuner that has shown itself to be particulrly suited for this? Power level will be 100-200 watts for the forseeable future.
I was also thinking of trying a horizontal loop over the fibergalss bed cap (I just have to try it). Would that work better with a certain style of tuner as opposed to a whip?


Title: What is the best mobile tuner?
Post by: AA4PB on September 26, 2003, 10:29:56 PM
If you keep the power down to 100 watts, I'd recommend the SGC SG-237. It'll tune a 102-inch whip from 75M thru 6M. It will also work with any radio - not restricted to a particular brand/model.

If you are using it with an Icom and want it to work with the Icom tune button, take a look at my web page at http://www.ham-kits.com for information on an interface that will do that.


Title: What is the best mobile tuner?
Post by: K0BG on September 27, 2003, 08:44:49 AM
If you have an Icom, the AH-4 will do a creditable job on 40 thru 6 meters coupled with the aforementioned whip. I have an SGC 235 (500 watt version) and although it will find a solution on 75, results are not spectacular.

By the way, it really isn't a "tuner", it's a coupler. The moniker ATU, or Autotuner is a misnomer.

One more item. The AH-4 is strickly a switchable LC, and when matching high inpedance loads like a long wire, the input SWR tends to climb near its matching range. The SGC units are also a switchable LC, but in some matching solutions, it adds capacitance to the input side thus becoming a Pi configuration. Both LC and Pi circuits are  less lossy than any "T" type you can buy.

Alan, KØBG


Title: What is the best mobile tuner?
Post by: AA4PB on September 27, 2003, 02:42:04 PM
I agree with Alan that the results on 75M with the SGC and a 102-inch whip are not "spectacular". My testing shows however that it does as well as a 75M Hamstick (also not a spectacular 75M antenna), but it may give you a point of reference. The SGC will allow you to get on 75M and make contacts with a 102-inch whip whereas the AH-4 will not (although Alan has a solution with a custom loaded whip). If you want to put out a big mobile signal on 75M then you probably should be looking at something other than a coupler and a 102-inch whip.