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Your final amplifier and driver stage most likely have lower gain on 10 meters than lower bands. Output should normally still be the same though. Radios are made with extra gain in the preceding stages to take care of this and provide uniform power out everywhere. They use ALC to reduce extra gain.

Seeing as how it behaves OK on CW and not on SSB the situation is probably low I.F. gain and/or the mic input to the radio was low to begin with.

Any SWR higher than 1:1 will start another gain reduction process to protect the final amplifier. Check into a known good dummy load to eliminate this cause. Why do I say known good dummy load? Because I just spent 4 hours bench time on a rig I killed testing into an intermittent estate sale dummy load!

Try another mic with more gain.

If this doesn't work then it's time for an I.F. alignment.

If the radio has an ALC meter the readings can help understand what's going on. You should have enough gain to make ALC on each band.

<blockquote data-quote="HiDef" data-source="post: 145439" data-attributes="member: 7734">Your final amplifier and driver stage most likely have lower gain on 10 meters than lower bands. Output should normally still be the same though. Radios are made with extra gain in the preceding stages to take care of this and provide uniform power out everywhere. They use ALC to reduce extra gain. Seeing as how it behaves OK on CW and not on SSB the situation is probably low I.F. gain and/or the mic input to the radio was low to begin with. Any SWR higher than 1:1 will start another gain reduction process to protect the final amplifier. Check into a known good dummy load to eliminate this cause. Why do I say known good dummy load? Because I just spent 4 hours bench time on a rig I killed testing into an intermittent estate sale dummy load!Try another mic with more gain. If this doesn&#039;t work then it&#039;s time for an I.F. alignment. If the radio has an ALC meter the readings can help understand what&#039;s going on. You should have enough gain to make ALC on each band.</blockquote>

[QUOTE="HiDef, post: 145439, member: 7734"] Your final amplifier and driver stage most likely have lower gain on 10 meters than lower bands. Output should normally still be the same though. Radios are made with extra gain in the preceding stages to take care of this and provide uniform power out everywhere. They use ALC to reduce extra gain. Seeing as how it behaves OK on CW and not on SSB the situation is probably low I.F. gain and/or the mic input to the radio was low to begin with. Any SWR higher than 1:1 will start another gain reduction process to protect the final amplifier. Check into a known good dummy load to eliminate this cause. Why do I say known good dummy load? Because I just spent 4 hours bench time on a rig I killed testing into an intermittent estate sale dummy load! Try another mic with more gain. If this doesn't work then it's time for an I.F. alignment. If the radio has an ALC meter the readings can help understand what's going on. You should have enough gain to make ALC on each band. [/QUOTE]

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