How do you setup a Flex 6XXX for AM mode

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When I try to use the AM mode on my 6500 they say I am still on side band. I am using 1.9.7. i checked the scope and it looks like i am on AM. The operators manual dosen't say much on how to setup.
Dennis KM6DF
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Dennis Daniel KM6DF

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Posted 2 years ago

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Jim Gilliam

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On AM the peak voltage amplitude of the audio is twice that of the resting carrier. When you modulate the peaks will give a peak power of 4 times the resting power. Therefore, you should not set your carrier level to more than 25 Watts or your signal will distort.
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Jim Miller

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I have run am a few times on my 6300 and since I run a 2 kw amplifier I have to set the power controfl so that the carrier runs about 350 watts and set the mic gain not to get into the red.  I leave the carrier level at 100.  On my last qso with several am guys on 75 meters I got very good comments on my audio.  One ham said it sounded as good as the best plate modulated tube transmitter.  After the qso I looked the man up on qrz and discovered I was speaking to Bob Heil who should know good audio when he hears it. 
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James Del Principe

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Dennis, when you key the rig, you should see a line representing the carrier. Next, when you speak, you should see sidebands on both sides of the carrier and they will rise and fall with your voice. They will not appear to be four times the height of the carrier on screen. You will only see peak power of four times on a good peak reading watt meter. It is true the carrier will (should) be 25 watts which gives 100 watts peak but.... only on a major voice peak. I hope this is a help to you. 73, Jim
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Alan, K2WS

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Dennis, make certain that the AM Carrier slider is all the way to the right. Otherwise you will sound distorted on AM receivers employing "envelope detection" or diode detection. The RF Power slider can be set to 100 or any level above 0.
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Ken - NM9P, Elmer

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Yes. On the 6000 series, the carrier level is automatically set to the proper level with the carrier level set to 100. Then set your mic gain so that it runs up to the yellow but never into the red on voice peakes. Do not use PROC or at least never more than NORM. But I recommend none at all. Set your TX bandwidth for 3000 Hz. (This is the audio bandwidth. Total TX bandwidth is twice that for AM. Adjust TX EQ for maximum clarity, remembering to readjust mic gain to keep in in line.

Then have fun!

The carrier level allows advanced users to reduce carrier level lower than the standard amount to provide a reduced carrier modulation which has greater than 100% positive cycle modulation while keeping the negative half of the cycle from going below zero. A little reduction, say to 95 or 90 can sometimes help some voices. But too much will be problematic for standard (non-synchronized) detectors.
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Andrew Russell

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If there is frequency selective fading (ie on the low bands) less modulation relative to the carrier may be better for conventional am detectors when the carrier fades.
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Ken, I’ve commented on this in the past, but it might be worth mentioning again. I use my 6500 with my ACOM 1000 amp, on AM. Without any modulation I set the RF output from the 6500 to produce 250W out of the ACOM 1000. That allows it to safely run at 1KW peaks (250 x 4). Next, I reduce the AM carrier level to reduce the resting carrier out of the ACOM to 100W. On peaks it’s still hitting the 1KW peaks. This really reduces the ACOM’s operating temperature, and it has not caused any problems while being received by both SDR and legacy “boat anchors”. It sounds incredible!

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Philip KA4KOE

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I been operating a 6300 on AM for over a year, and never had bad report. I do run it into and amplifier with about 20 watts carrier. I set rf power all the way up, set the carrier level for 20 watts , I use an external scope, and adjust the mic level, so the audio negative peaks are close to base line. This gives me slightly more than 100 percent positive peak, but not too much to be distorted in diode detector. I have processor on in normal position, seems to give more dense audio, with no ill effects. Good luck.
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James Del Principe

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Hasn't been said yet that I can see but my AM group on 75 mornings always uses SAM...synchronous detection. Makes a big improvement during selective fading. BTW, we do not reduce carrier but I may try that...... and no processing.  Sounds great.   73, Jim