designing a preemphasis filter

Narax wrote:
> Sorry, I accidentally hit the "Send Message!" button.
> 
>> Notice that the pre-emphasis has about 15 dB or more boost at high
>> frequencies, make sure that this does not casue OVEVERMODULATION to
>> your modulator.
>>
>> Mark
> 
> Thank you for this hint - I didn't take this in concideration till now and
> I think this is the first thing the check out.
> 
> 
> One more question about the RC-curcuit: You said that I should take its
> phase response. But a simple RC-curcuit has a diffrent magnitude response
> than I want to achieve. Is a mix of the desired magnitude response and the
> RC-circuit's phase response a good design?

The deemphasis filter in the receiver is a simple RC. The preemphasis 
filter should complement it, and the complement is also a simple RC. Why 
do you want a different response?

Jerry
-- 
Engineering is the art of making what you want from things you can get.
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>The deemphasis filter in the receiver is a simple RC. The preemphasis 
>filter should complement it, and the complement is also a simple RC. Why

>do you want a different response?
>
>Jerry

My mistake. I don't want another response.

Things are beginning to work fine - I just now took a look at the results
from the FDLS algorithm and they are good. As always I have another
question: What is the artificial delay good for? I know that things don't
work fine without it, but why?

Narax wrote:

   ...

> Things are beginning to work fine - I just now took a look at the results
> from the FDLS algorithm and they are good. As always I have another
> question: What is the artificial delay good for? I know that things don't
> work fine without it, but why?

How does the frequency-domain Least squares algorithm enter the picture? 
I don't know which delay you mean, but one commonly adds a delay to 
match an unavoidable delay in a parallel part of a process.

Jerry
-- 
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯