The Studer "90°" Dome Filter Stereo to Mono Quadrature Summer

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mediatechnology
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Re: The Studer "90° Filter" Stereo to Mono Summer/Recorrelator

Post by mediatechnology »

Putting the final touches on the "Quadrature Summing Filter" board.

Image

I eliminated the relay which forwarded I and Q as "stereo" to the final output.
That would almost never be used except for people wanting to do sin cos detection and draw flower petals on the oscilloscope.
I provided the separate I and Q outputs on a header.
The board is 3.7" x 2.75".
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mediatechnology
Posts: 5173
Joined: Sat Aug 11, 2007 2:34 pm
Location: Oak Cliff, Texas
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Re: The Studer "90° Filter" Stereo to Mono Summer/Recorrelator

Post by mediatechnology »

This is the current schematic for the "Quadrature Summing FIlter" layout.

I decided to eliminate the ability to route the separate I and Q components to the final outputs to save a relay and board space.
This mode would not be used in most applications.
I and Q now come up on a header where they can be used in a sin/cos output configuration for instrumentation applications.
J1 optionally routes the Left input to both allpass chains for a "one in two out" mode.

Image

The board is 3.7" x 2.75"

Image
User avatar
mediatechnology
Posts: 5173
Joined: Sat Aug 11, 2007 2:34 pm
Location: Oak Cliff, Texas
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Re: The Studer "90°" Dome Filter Stereo to Mono Quadrature Summer

Post by mediatechnology »

Quadrature Summing Filter boards are on order and should be available in about 7-10 days.
I'll be building one to check the layout as soon as they arrive.
The BOM for parts excluding PC board looks to be about $101 US.
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