crt ss6900n low on modulation ??

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WARLOCK
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crt ss6900n low on modulation ??

Post by WARLOCK »

i have a rca ss6900n i bought off a member on here , i keep getting bad reports of my modulation is quite low the ic9 is set on 63 , i have tryed a power mike still reports are that the modulation is low anybody got any thoughts as to whats wroung ??
108EH002
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Re: crt ss6900n low on modulation ??

Post by 108EH002 »

Take it you have the original mic aswell as power mic and is this in all modes = am/fm/ssb George ?

If only on FM then it could be the variable resistor that is marked usually FM Dev,as this is set too low ?

Does the mic need the wire on pin 4 disconnected ?
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Retro_CB_Dude
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Re: crt ss6900n low on modulation ??

Post by Retro_CB_Dude »

I'm having similar problem, and wondering if there is an interal adjustment ? Or perhaps something could be removed for more AM audio in my case?
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ch25
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Re: crt ss6900n low on modulation ??

Post by ch25 »

Low means how much percentage measured with the scope?
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Retro_CB_Dude
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Re: crt ss6900n low on modulation ??

Post by Retro_CB_Dude »

No it means compared to majority of my other radios I use hooked up using as a base setup through my beam with low SWR basically. I'm not talking a BIG problem here but curious if there is a trimmer inside the unit for mic gain too. Don't know if they are marked inside either. Seems someone would know for sure without having to pop the cover myself. I know the mic gain on mine is in the menu for the 1st option having version 6 here!

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Re: crt ss6900n low on modulation ??

Post by ChubbyChops »

W501 is AM mod adjustment.
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Re: crt ss6900n low on modulation ??

Post by Retro_CB_Dude »

Thank you CC, much appriciated. Yeah not wanting it on default for AM, typically a bit LOW. AM here in USA tends to get a bit rough sometimes and one needs to be able to punch through with good solid clear audio. I don't like to over drive the circuit either! Wonders if clockwise is up or down, but it'll be easy enough to tell.

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