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One more note. The PLL Alignment is spot on. Yes the PLL Alignment is different than most I've done. It is complex because of the 100 Hz resolution.

With no modulation there is a hum in the carrier. I can hear this on a radio without an antenna. Also I can see about 500 mv of that same hum on the scope with no modulation. I think if I can find the source of that hum, I will solve the problem. Also note that side band is perfect. No spurs and...

if i showed a video you would see that there is modulation components in the spurs.

Here is the Spectrum and Scope readings. I'm just getting back into this one. Thanks for your input. This is the result of even a slight amount of mic gain.

This is audio related. Thanks Brandon! I was mistaken. I thought I had tested this rig with the mic gain down. The problem goes away when the modulation is all the way down. I installed a new limiter and replaced the clipped resistor Q32 and R291 respectively. I also removed the resistor on the...

The audio is low and muffled. Transmits the same with mic gain all the way down. I have a full bench. Spectrum analyzer, scope, signal generator, frequency counter and audio analyzer. This unit is literally transmitting on 6 channels. I'll post images of the spectrum when I get a chance. Also...

This radio transmits perfect on sideband, but on AM it has garbled audio and transmits on 6 channels. I have checked the alignment of the PLL System and found everything perfect. The am detect circuits check good also D34 and D35 also Q24 all test perfect. I saw something on this before but...

Thank you midnight special!

Final update... after much study and learning more about the spectrum analyzer. I learned that modulation is what skews the amplitude measurement. NOTE (AM modulation is by default asymmetrical) but not as drastic as illustrated in my original post. The nonsymmetrical reading that I was getting...

Update... The 10.695 crystal and circuits are good. Double checked the PLL Alignment... all is perfect. I'm hoping someone can help me understand the principles that effect the symetry of what is shown on the spectrum analyzer. I've hit the books on this one, but nothing I can find addresses...

Thanks nomadradio… I will look at your recommendations. The mic gain makes no change in the distortion. The power level does affect the amplitude but the symmetry is still off. That’s what I was trying to show in the pics. I suppose I could have provided details with each pic. Thanks again!

Connex Saturn EPT360015B audio is choppy... I'm working on this thig, the best way to describe this audio is it sounds like you are talking through a fan. I have done a full alignment and eliminated all the mods to this radio. The spectrum analyzer shows that the lower side and the upper side...

I like the way you think! Very cool!

Thanks to you all. This site is a treasure.

Bias problem corrected. Thank you Andy. I am new and Learning. I need to reed more. I am currently reading everything Lou Franklin had to sell. Andy do you have any good recommendations on books to read?

Thank you for your time and great explanation Andy. I will let you know how it goes. Out of time today. This makes sense and I was thinking I needed to reduce the bias voltage, I just didn't know how.

What’s your armchair diagnosis if it’s not converted?

Nothing is shorted. The driver transistor checks good out of the radio. It’s probably something really dumb.

The driver current is 10.45 amps yes 10.45 whole amps. The finals combined current is 100ma.

I will measure the current and post it later today. Sorry!