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Audiophile73
Junior Member
Username: Audiophile73

Post Number: 42
Registered: 5-2004
Posted on Saturday, January 29, 2005 - 5:30 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

ok i have an issue I am driving a xforce 400 with a texas star modulator. My radio keys 2 watts but I think thats too high. So I need to be able to play with it a bit. My tech told me that messing with the coils L13 and 14 changes the frequency is this true. So do I just turn L12 to get the dk I want or what. My radio is a uniden pc78. I need help PLEASE
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Patzerozero
Intermediate Member
Username: Patzerozero

Post Number: 370
Registered: 7-2004
Posted on Saturday, January 29, 2005 - 9:58 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

you're looking to get approx 250watts (on a good meter) dead key from the 400, assuming it's a 4-2879 with no driver stage,(if xforce is variable, set up with variable FULLY clockwise). texas star modulator is more then up to handling 3-4 watts dead key, so key TS up with variable set low, and adjust TS clockwise til output from xforce is in that 250watt area. shut off xforce & double check TS dead key(for reference purposes) could be anywhere from 10-40 watts deadkey. when setting multiple amps up this way, you need an accurate & reliable wattmeter. 78 with 3.5 watts dead key probably has an honest 11 or so watts swing on that accurate peak reading meter, maybe about 7 watts swing on that accurate RMS scaled meter, again well within the texas stars handling capabilities, and whatever swing you get out of the TS, maybe honest 80 watts pep, the xforce can handle that and then some. your 78 keying 2 watts if fine, if anything a bit low even. not enough input to amplifiers, though not as damaging to transistors as being overdriven can make the output sound just as crappy.

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