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Ah, the joys of running the TH-F6A. I suspect the following:<br><br>The remote mike button functions are wired as different resistances into the mike circuit.<br>Like remote mike button 'A' is a 10k resistance, remote mike button 'B' is a 15k resistance<br>across the mike circuit, etc. I don't remember the exact values, but you get the idea.<br><br>I've found that the after market plugs don't quite fit into the jacks properly on the side<br>of the radio. The jacks are recessed slightly, meaning the outer shell or cover for any<br>external plug must be very thin. This<br>means the plugs are almost, but not quite, seated into the radio jacks. When this <br>happens, the slightest movement outward on the plugs will trigger a channel change,<br>vfo mode switch, or some other strange behavior in the radio, even if you lock the<br>functions. I think the lock only affects the buttons on the radio, not the external<br>mike functions. <br><br><br>Even if you bought the cable from the open tracker folks, it may still just use more<br>standard sized plugs.<br><br>If you made your own plug, be aware that the ground or return for the mike circuit is not<br>the shell or shield on the (larger) mike jack; it's the shell on the audio output jack.<br><br>I have a cable I made from external parts, with very narrow shells, that do seat properly<br>into the jacks. I can let you borrow it.<br><br>Or maybe better yet, I have a known-good<br>Radio Shack HTX-202 you could use. It uses the more standard wiring for audio and mike:<br>the larger 3.5 mm or 1/8 inch for external speaker, 2.5 mm or 3/16 for the mike, with<br>a 10K to ground to key the thing. When powered by 12 volts, it's rated to 5 watts out,<br>and the usually measure pretty close to that. BNC RF connector, standard barrel sleeve<br>for input power. <br><br>Everything about the Kenwood is odd, as far as connectors are concerned.<br><br><br>> Date: Wed, 4 Feb 2009 16:35:58 -0600<br>> To: craprs@rf.org<br>> From: info@n-connect.net<br>> Subject: [CRAPRS] Radio Problems<br>> <br>> Posting from the CRAPRS mailing list:<br>> I've got an Opentracker2 in my truck connected to a KenwoodTHF6A, and <br>> an external antenna. It's a "waste" of a tribander to use it on <br>> APRS, and I've got another HT on my list of radio gear to acquire, <br>> but for now, the Kenwood is all I've got.<br>> <br>> The problem I'm having with it is that it changes channels. <br>> Completely randomly. Sometimes it's fine for weeks, and other times, <br>> it changes channels after only a minute of use. It's worse when I <br>> run it off it's internal battery, so I run it off 12 volt vehicle <br>> power. And it's random. It will randomly change to some memory <br>> channel.<br>> <br>> I've got some snap on chokes, for the mic and audio cable, but they <br>> don't seem to have any effect. Running off the HT's antenna (crap for <br>> getting packets out, but I wanted to test it) or external roof top <br>> mag mount doesn't make any difference. Normal power is 5 watts. <br>> I've run it on .5 watts, and .05 watts, and have seen no difference. <br>> And yeah, you CAN actually get some APRS packets out on .05 watts. <br>> But not many, and not far from a digi. :-)<br>> <br>> I've set it to one band use only, and always run it with the controls <br>> locked when I use it as an APRS radio. I also run it in VFO mode, <br>> since I do not have a memory setting for 144.390. So VFO, one band <br>> mode, controls locked, and it still manages to change to some random <br>> memory channel. Since I have a lot of channels in memory that I <br>> can't transmit on, (radio works well as a scanner too) I usually land <br>> on one of those channels, so it's no real harm. But one of these <br>> days, I'm going to land on a repeater channel, and blast it with APRS <br>> packets.<br>> <br>> And that day was today, when I noticed it was on 444.225. (Dubuque?) <br>> I'm not sure if that is a working repeater, or not.<br>> <br>> And it stays locked during the channel change. I have to unlock it, <br>> and change it back and relock it.<br>> <br>> Anyone have any ideas?<br>> <br>> _______________________________________________<br>> CRAPRS mailing list<br>> CRAPRS@rf.org<br>> http://rf.org/mailman/listinfo/craprs<br><br /><hr />Windows Live™: E-mail. Chat. Share. Get more ways to connect. <a href='http://windowslive.com/online/hotmail?ocid=TXT_TAGLM_WL_HM_AE_Faster_022009' target='_new'>Check it out.</a></body>
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