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Sg569
Junior Member
Username: Sg569

Post Number: 35
Registered: 12-2004
Posted on Friday, January 14, 2005 - 12:08 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Does ANYONE have any plans to build a noise filter?? How about a pre-amp???
Just curious
Thanks
sg569
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Bruce
Senior Member
Username: Bruce

Post Number: 2094
Registered: 9-2003
Posted on Friday, January 14, 2005 - 10:51 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

do you mean like for a receiver audio output ????

There are 3 ways

1) audio bandpass ( MFJ MAKES SEVERAL )

2) SCAF bandpass audio filters ( fancy bandpass )

3) DSP ( digital ) filters

I use all 3 and dont realy find any of them highly effective ..... but every bit helps!
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Sg569
Junior Member
Username: Sg569

Post Number: 42
Registered: 12-2004
Posted on Saturday, January 15, 2005 - 3:15 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks Bruce
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Sg569
Junior Member
Username: Sg569

Post Number: 45
Registered: 12-2004
Posted on Wednesday, January 19, 2005 - 2:53 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

I think I was looking more for a filter to hook up into the power leads. The pre-amp for recieve purposes(cb).
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Bruce
Senior Member
Username: Bruce

Post Number: 2111
Registered: 9-2003
Posted on Thursday, January 20, 2005 - 4:51 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

ok try http://www.palomar-engineers.com/Ferrite_Beads/ferrite_beads.html

This place has good stuff and been around a long time.

As for a receive preamp I use a EP-27 preamp bought from copper when i need one and if i get a chance i might replace the transistors in it with 2sc2999's ...... that should realy make it a hot one. If i get the chance to do that and it works i'll let you know.

Another very good preamp is made by HAMTRONICS for 10 meters ( They make 6 2 and 440 too )
Not cheep and its just a board you put in a case with some sort of switching but its noise figure is down less that .5 db and gain is better that 20 ...... MORE than enough.
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Sg569
Junior Member
Username: Sg569

Post Number: 47
Registered: 12-2004
Posted on Thursday, January 20, 2005 - 8:45 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Bruce, I went to ********* web site, and they advertise a pre-amp for $ 39. wired& tested, I know that I could pick up a Bandit pre-amp for about $35+ shipping and tax....
******************* also advertises a "lil pre-amp" for like $14 it installs inside the radio, but dont give any db gain figures.
I know where to find the premade, but doggone it I wanna build one, I wanna, I wanna, I wanna.
lol
yes I know I would end up spending more for the parts and for my time than what it is really worth; But noone pays me for MY "me" time, I get bored easily. I want the project, to learn from
Thanks,
sg569/ Walter
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Bruce
Senior Member
Username: Bruce

Post Number: 2114
Registered: 9-2003
Posted on Thursday, January 20, 2005 - 11:02 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

HE HE HE my kinda tech! I love building them my self. Except for ramsey and TENTEC i dont know of anyone selling any kind of kits .... the little preamp is junk i still have one in the bag. The problem is we are a dieing breed so many out there have no intrest in building kits
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Sg569
Member
Username: Sg569

Post Number: 51
Registered: 12-2004
Posted on Friday, January 21, 2005 - 3:09 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Thanks Bruce

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