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SSB modulation needle swings backwards

R

Radiopunk0

Member
Jul 31, 2022
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I have a Galaxy 979F, 3 watts going into a KL 203P amp. I noticed recently on ssb that my mod needle on the TC3001-P swr/power/mod meter swings backwards. Works fine on AM. Doesnt affect my DX work on ssb. My QSO heard very well. (Note) on the 979F, the mod & power needle is 0 unless i talk. So i dont think prob is radio. Tried to reduce dead key to 1 watt but still same effect. My power supply MFJ 4035MV works perfect. My antenna cable isnt compromised. Like i said, only on ssb. When i power up, it goes into the red near set and when i talk, it back swings... Im at odds on this but im thinking the meter. Any suggestions please
 
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FlatlandBusa said:
Dead key shouldn't have anything to do with SSB. Are you showing any output on SSB which the mic keyed and not talking? SSB watts should be zero unless modulating.
Click to expand...
You are correct, i shouldnt have anything until i talk on ssb. When i key up, i have 60% mod reading just from keying up on meter. Not even talking. Once i talk it does bounce to 80 and drops to 0 and back up to 60. Im thinking meter is wonky
 
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Have to agree with the other guys, if you turn the mic gain down and key the radio with no modulation there should be zero carrier, no output.
If you do have a carrier you have a problem.
Try this on both upper and lower side band and report back.
Trying to read modulation on that meter on SSB will not work.
There is no carrier to modulate.

73
Jeff
 
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Radiopunk0 said:
Tnks Jeff ...on ssb when i key I have 60% mod reading just from keying up on meter. Not even talking. Once i talk it does bounce to 80 and drops to 0 and back up to 60. Im seeing now that the radio reads 0 for power & mod. But on the external meter, both needles are moving some. I think the meter is defective
Click to expand...
 
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sp5it said:
On SSB there is no dead key.
If you see dead key power on SSB yor radio is defective.
Click to expand...
You are correct. I meant to say using a 3 watt input. Radio & mod Power indicator is 0 until i talk. But on the external meter the Power & mod is showing numbers. On my radio its 0 until i speak .Im thinking prob is meter
 
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My final diagnosis is the TC3001-P external meter is defective. On ssb both the power & mod needle moves when it shouldnt. Thank goodness the radio works as should showing 0 until speaking. The external meter is not interfering with my dx qso's but its not accurate. Retired on fixed income, i will have to wait for another meter. Thanks to all who helped. Really appreciate it
 
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