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615_ri
Junior Member
Username: 615_ri

Post Number: 44
Registered: 5-2006
Posted on Monday, May 21, 2007 - 4:54 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

is this possible?? i know i did it on my vr9000 from the subscriber sections. thanks.

kenny
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Dale
Advanced Member
Username: Dale

Post Number: 882
Registered: 12-2002
Posted on Monday, May 21, 2007 - 8:38 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

i believe its possible but im not sure
exactly what ya gotta do for that mod
dale/a.k.a.hotrod
cef426
cvc#64
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615_ri
Junior Member
Username: 615_ri

Post Number: 45
Registered: 5-2006
Posted on Tuesday, May 22, 2007 - 3:59 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

oh. that would be great if someone knew how to do it. do you just need to run 12v to the final?
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2600
Advanced Member
Username: 2600

Post Number: 591
Registered: 7-2002


Posted on Monday, May 28, 2007 - 2:59 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

This trick will REDUCE the modulated swing on this radio by a factor of three or four.

In a SSB radio that uses a transistor as the AM modulator, the main 13.8 Volt DC power passes through it, with a loss of about two Volts. Jumping around that transistor to feed power directly to the final will increase the peak power on AM, or at least bring it up equal to the SSB peak power.

The Cobra 29 uses a different method. An audio transformer steps up the (approx) 12-Volt audio signal to about double that much. This puts a peak modulated voltage ONTO that final that is 24 Volts or higher.

If you "power jump" around this, and hook your 13.8 Volt DC power directly to the final, this will REDUCE the final's peak output.

Can't figure out who would be looking for that result on purpose.

The power jump is only helpful in a radio that does NOT use a transformer as the AM modulator.

73

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