[Lowfer] Wild Bill's Loop Lessen #51

Tue, 12 Nov 2002 00:51:40 -0500

> BTW: Be darn sure that the Vcc current you are reading on the
> final is for
> the output transistors alone and not for any other active component.

I gave the computer a exciter-ectomy and have the subject board on my
kitchen table. If the WX forecast holds for tomorrow I will not be able to
do my yard work (DARN!) and I will put the patient under a microscope in an
attempt to trace out the schematic of (at least) the final.

If possible I will remove the pi filter at the final.

Mike

> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]]On Behalf Of Bill Ashlock
> Sent: Monday, November 11, 2002 5:37 PM
> To: [email protected]
> Subject: [Lowfer] Wild Bill's Loop Lessen #51
>
>
> Mike S,
>
> >the LW-MAX's final was drawing more current than expected:
> 250mils >@11.5V
>
> 2.87 watts. Yikes! The output transistors must be smokin! Tis a
> good thing
> you are reading approximately .83A on the loop, which is equal to the
> current that you read when you substitute the 1.3 ohm test coil.
> This says
> that loop AC resistance is also 1.3 ohms and the signal you have been
> sending represents a .95W output from the LW-max. The problem is with the
> efficiency of the output stage of the LW-max - about 35%! A scope
> you would
> likely show you the filter is the cause of the problem.
>
> BTW: Be darn sure that the Vcc current you are reading on the
> final is for
> the output transistors alone and not for any other active component.
>
> Bill
>
>
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