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Allan
Junior Member
Username: Allan

Post Number: 40
Registered: 2-2006
Posted on Saturday, March 25, 2006 - 1:52 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Prolly a DA question but, I am limited to my experience with these devices, mostly the mobile 12 volt models (broadband 3-30 type), but have noticed trimmers in some models. Some have one, others have two, and some with none at all. In the old tube amp days, I remember there were the load, plate, tune, and other air capacitors in them for tuning purposes. In the tranny models, are these small trimmers to dial them in, or to make up for components with broad tolerance specs, or what? What about the ones with none? Just curious. Any input would be appreciated. Thanks...... Allan
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 2616
Registered: 7-2004


Posted on Saturday, March 25, 2006 - 5:46 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

you pretty much got it allan. just an attempt to get 'em near 50W. some are a hard value & they hope for the best, some adjust to get 'em as close as possible.
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Allan
Junior Member
Username: Allan

Post Number: 41
Registered: 2-2006
Posted on Saturday, March 25, 2006 - 7:22 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Ahhh. Well, I've had the ones that were without trimmers, with horrible results in the radio/amp marital match-making, and others that were spot on when trying to set the SWR's. Thanks, again, Pat. Another round for the radio god.
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Allan
Junior Member
Username: Allan

Post Number: 44
Registered: 2-2006
Posted on Saturday, March 25, 2006 - 10:28 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

About the ones with trimmers. Would you tune them for max watt output, or back the output off, with a little forward swing, pushed by the audio? Seems like the ones driven wide open sound 'muddy', or is it mainly "crud in, crud out" what I am hearing on some units?
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Patzerozero
Senior Member
Username: Patzerozero

Post Number: 2619
Registered: 7-2004


Posted on Saturday, March 25, 2006 - 10:44 pm:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

if you're sure it's on the coils of the output transformer, it actually is SUPPOSED to help match the amp up at 50W, it shouldn't affect power in any way. the RADIO is what should be adjusted to make the amp dead key X & swing Y. crud in = crud out most of the time. & if in is OK & crud is still out, radio is most likely overdriving amp.
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Allan
Junior Member
Username: Allan

Post Number: 46
Registered: 2-2006
Posted on Sunday, March 26, 2006 - 6:51 am:   Edit Post Delete Post    Move Post (Moderator/Admin Only)

Gotcha. Thanks....

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