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Hi,
Could anyonr tell me about negative swing on AM, and if anyone has remedied that situation. I know the more modern rigs have really NO place on am. But I have a mic that sounds good on am as far as good audio signal reports go, and have an amplifier. But needless to say the amp doesn't work properly with a reversely swinging radio. It swings in reverse at any power level and with any audio adjustment. Any ideas would be sweet !!

Thanks in advance
Joe K0TRT
jwhawg

How do you have it set on the radio settings?? I know the older radio owners manuals said 25 watt carrier and adjust mic gain until you see the neddle on radio meter just start to move while you speak into the microphone.

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""""was not thinking of a cber sat with his makita screwdriver winding round the presets untill his meter said s9+60db from a guy on a handheld 15 miles away""""

well that's pretty much what the manual says about setting up to transmit on am. But like I said, it really doesn't have any affect on the negative swing. Any position and combination of settings.

Hmmm?? and you have good SWR?

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""""was not thinking of a cber sat with his makita screwdriver winding round the presets untill his meter said s9+60db from a guy on a handheld 15 miles away""""

Yep. 1.2 to 1 on most of my antennas. But here is something..... This rig puts out a heck of a lot more that 25 watts on am. Somewhere around 40 watts. I think I'm onto something. This thing is probably "swamping" the audio.

It will swing forward ofcourse but you should put no more than 25 watts at dead key no audio Id put less say between 10 and 20 Watts. Try 10-15 watts deadkey and adjust that mic gain so it just tickles the radio meter as far as movement on output reading I am thinking this is gonna help. You have to remember there is crazy audio in these HF rigs and they are very very touchy.

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""""was not thinking of a cber sat with his makita screwdriver winding round the presets untill his meter said s9+60db from a guy on a handheld 15 miles away""""

It puts out 40watts dead key with NO audio input what so ever. Any audio input at all, no matter how minute will cause a reverse swing on any watt meter I have tried. My swamping theory is wrong because even with the rf power turned all the way down (5watts) it still does it. It does it with the stock mic hooked up to it. Although it has very little audio. ??

Ok so it shows 40 watts deadkey no matter where you adjust the variable power??

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""""was not thinking of a cber sat with his makita screwdriver winding round the presets untill his meter said s9+60db from a guy on a handheld 15 miles away""""

No. It puts out 40w with the rf power up all the way. I think it's only suposed to do only 25w on am, rf power adjustment all the way up. I can adjust it down to 25-30w, but that's with thr rf power at about half. On side band it does it's rated 85-100w. But the fact remains, even with power ADJUSTED back to rated power for am, I still get neg swing.

Ive had a few older radios that did way more out than 25 on dead key with the power all the way up but I just adjusted them to 15 - 20 watts and adjusted the mic gain. To much audio is going to make it swing backwards but there could be another underlying problem one of the other guys may interject here this afternoon with more ideas.

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""""was not thinking of a cber sat with his makita screwdriver winding round the presets untill his meter said s9+60db from a guy on a handheld 15 miles away""""