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Re: Help FT-847 and HEIL ...



Tnx KE9NA and AA2BN for the anwers ... Just removing two SMD 2K2 on 
PHONE-UNIT and working OK now !


 >The FT-847 is designed to support headphones with an impedance of 32 Ohms.
 >The Heil and Kenwood phones usually 4 or 8 Ohms.
 >You may remove the attenuator resistors located on the headphone jack
 >unit. These are SMT resistors that are colored RED, and will change the
 >impedance of the jack to match your Heil phones.

 > On the Schematic labeled "FT-847 Connection Diagram" the Phone Jack Unit
 > circuit is in the upper right hand corner. There are two resistors shown
 > there. They are labeled as R8501 and R8502 (One goes to the left earphone,
 > the other to the right - separate but identical circuits). Both are 100 Ohm
 > 1/2 Watt resistors (leaded) Now, what the schematic doesn't show you is 2
 > 200 Ohm (labeled on the resistors as 2R2 which if I remember chip resistor
 > lingo correctly is 200 Ohms) chip resistors to ground that make a voltage
 > divider with R8501 and R8502. The leaded parts are in series with the
 > headphones when plugged in and the chips shunted to ground. >

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