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Fusebreaker
Intermediate Member
Username: Fusebreaker

Post Number: 188
Registered: 3-2004
Posted on Saturday, September 17, 2005 - 11:27 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

1.Adjust VR1 for maximum recieve.(will see big improvement).
2.Set the radio to channel 20,Key the radio,Adjust L14 for right on 4.0 watts of carrier.
3.Solder a 150k ohm resistor across the PA and external speaker solder lugs.
4.Turn mic gain(dynomic) to max,say 1-2-3 in your regular voice dont scream!!!,Adjust vr4 until the modulation is loud with 0% distortion.
if it is set to high the tune up is worthless and you might as well toss the radio out the window.
5.By removing the resistor it disables the talk back but if you want you can leave it in the radio.(Leave It).If you get a high pitch sqeel when you talk change the resistor to a 200k ohm or high until sqeel is gone.In order for your radio to be tuned correct the owners voice and mic type play a big part if you go from a power mic to an RK-56 type noise cancel mic then your modulation will be to low so if you change your mic readjust Vr4 then it will work with the same modulation as you had before the new mic.
If you exceed 4 watts carrier then its likely your modulation will swing the power of your radio down instead of forward then you just wasted the tune up. Say you set the carrier to 6 watts well it will go from 6 watts down to 2 or 3 watts wHEN you modulate.Swing is not everything but there is a balance that must be respected to make a radio operate correctly.FROM MY EXPIERIENCE A 4 WATT CARRIER THAT SWINGS TO 7 OR 8 WATTS IS PERFECT BUT OPIONIONS VARIATE SO THIS IS A GUIDE IF YOU USE IT THE LADY AT THE MCDONALDS 2 BLOCKS AWAY WONT HEAR YOU AND IF YOU DONT WANT THE FFC TO KICK YOUR DOOR IN WITH A WARRANT THEN FOLLOW THE MODULATION RECOMMENDED.


I GOT BORED LOL HOPE SOME ENJOYS THIS
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Dragon883
New member
Username: Dragon883

Post Number: 4
Registered: 2-2019
Posted on Saturday, November 14, 2020 - 11:47 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

For those of you reading this... vr1 does NOT increase your "receive"... it only turns up the METER DISPLAY.
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Charliebrown
Advanced Member
Username: Charliebrown

Post Number: 735
Registered: 10-2002
Posted on Sunday, November 15, 2020 - 11:29 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

what does soldering a resistor across the pa do ? I never heard of that one
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Bobicpfan2
New member
Username: Bobicpfan2

Post Number: 7
Registered: 8-2011
Posted on Saturday, April 10, 2021 - 4:44 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

VR2 is the S meter adjustment. NOT VR1. disregard what Dragon883 said

CharlieBrown - the resistor adds talkback

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