>Hello I am looking for some help I am new to using amplifiers in Ham radio
>I have been a ham for about 12 years but have just started using a amp. I
>have a ten tec Jupiter and use two antennas 1) a tenadyne LPA up at 65
>feet tower is 150 feet away from the house. this antenna is for
>10,12,15,20, mtrs . swr averages at 1.4 : 1
>2) A Carolina Windom by w4cox up about 40 feet and vertical portion
>about 50 feet away from the house with one of the legs of the dipole
>running over the houseabout 18 feet above the roof . this antenna covers
>the remainder of the bands minus 160. with out the amp both antennas work
>fine however when I use the amp the LPA beam works fine but the Carolina
>Windom doesn't work well on 40 or 80 meters. when used there I am told
>and I have listened to the audio , I have a bad flutter to my audio once
>referred to as the sound of a machine gun . Also when I tune the amp with
>low power on 40 or 80 I get a pulse sound that sounds like it comes from
>the amplifier . The sound makes noise like sending cw dots from a keyer
>at about 15 words a minute when this happens the meters still look good
>where they are supposed to be . I have all my station grounded ,
** There is no such thing as a 0v-potential RF-ground.
>I have
>checked all my jumper cables for shorts , ( although two patch cables are
>at about 6 feet too long ? ) when using the Carolina Windom I use a Nye
>Viking antenna tuner to get a flat match ( about 3:1 on 80 and 2:1 on 40
>meters with out the tuner) my centurion is about 4 years old and I was
>instructed by TT to complete the mod needed to use with newer radios ie.
>jumper the diode etc.( mod completed ) by using the load and tune
>controls on the amp I can make these sounds go away but power put out by
>the amp goes down. when I tune the amp for no crazy noise the audio is
>still fluttering . and by the way my satellite tv on the upper floor is
>now bothered by TVI . the phone is not affected. The mic gain is at
>about 14percent and the speech proc is off on the Jupiter . sorry for
>the long post . any and all help will be appreciated . John
** Do you use a coaxial choke balun after the amplifier?
http://www.somis.org/bbat.html
see figure 1C.
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