ALC (automatic level control) - RF Cafe Forums
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Below are all of the forum threads, including all the responses to the original posts.
Post subject: ALC (automatic level control)
Unread postPosted: Tue Mar 16, 2004 1:28 am
Joined: Tue Mar 16, 2004 1:26 am
Anybody know how I can design an ALC circuit with a pin attenuator and a crystal detector. Freq range (DC - 500 MHz).
Post subject: ALC
Unread postPosted: Tue Apr 20, 2004 3:40 pm
Coupling off the output, convert to dc with the crystal detector and varyig the PIN diode with the dc at the input. :|
Unread postPosted: Tue Apr 20, 2004 9:15 pm
Joined: Sun Aug 03, 2003 2:02 pm
Location: Erie, PA
* Here's a really good App Note on how to build a PIN atteunator from Alpha Industries (now Skyworks).
...and another from General Microwave (now Herley).
* Here's an App Note from Agilent for a detector.
...and another from the Electronic Warfare Handbook site.
These and others can be found on the App Notes page right here on RF Cafe.
Good luck to you.
- Kirt B. :mrgreen:
Unread postPosted: Wed May 05, 2004 3:30 pm
Think about the time response and you will get it. With properly made ALC you can get 6dB or more s/n ratio for voice. Video is different. Generally it provides dynamic range compression.