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27mhzman
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Username: 27mhzman

Post Number: 1
Registered: 7-2004


Posted on Friday, July 23, 2004 - 10:06 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

there are people makeing mods by installing dual finals in these radios.Does anybody know about this mod?were can i get the part numbers as they are scraping them off.
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Tech808
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Username: Tech808

Post Number: 3119
Registered: 8-2002


Posted on Tuesday, July 27, 2004 - 9:37 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

27mhzman,

Sorry do not know about the Dual Final Mod on a Cobra 25 but here is the Information that I do have for more power.

Mods for the: Cobra 25LTD / GTL / CLASSIC

#1 ~ Adjust VR-5 for Max modulation.

#2 ~ Adjust L10, L9 and L8 for max RF output.

OR

#3 ~ Power Modification:

Change stock final to a 2SC1969 Adjust L10,L9,L8 and Change C91 to a 33uf 16volt polarized electrolytic capacitor.

Hope this helps.

Lon
Tech808



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Tech548
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Username: Tech548

Post Number: 173
Registered: 5-2004
Posted on Tuesday, July 27, 2004 - 6:57 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

27mhzman

There's far more to it than meets the eye. Not only do you have to duplicate the componets in the final circuit, but they also have to be parelelled.

And there's just no room in the 25 to successfully do this. And even if you could, there isn't enough buffer and driver there to drive the two finals to a respectable RF power level where anyone on the receiving end would even notice. You have to more than double your RF power just to come up a half S-Unit. Two finals in a Cobra-25 would never accomplish this.

It would cheaper just to invest in a duel final 10 meter radio. 10 meter radios are getting cheaper and cheaper all the time.

Jeff
Tech548

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