RDS

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   Have you tested this with your transmitter?  IIRC, mono FM has a pilot tone at 19kHz and stereo FM adds a L-R difference signal at 38kHz.  In order to prevent the incoming audio signal from interfering with these signals (added by the transmitter) a low pass below 19kHz is typically applied to the incoming audio.  In other words... a device like this is not compatible with every transmitter out there.  

The release notes show this device being introduced at after the audio is multiplexed (19kHz low pass already applied and 38kHz subcarrier already created)... do you know how to find this line and modify your transmitter accordingly?  (This device is not just plug and play into your typical Ramsey/Belkin box... hardware modification will be required to tap the MPX signal).  I believe we have a broadcast engineer in our midst that can correct anything I might have messed up... it has been a while since I studied RF from an EET perspective.

It is an interesting concept and I will make a note of it, but this is not on the project plan at this point in time.

Edited by LightsOnLogan - 29 Aug 2008 at 3:29pm

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LightsOnLogan Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Joined: 11 Oct 2007 Online Status: Offline Posts: 3187	Quote Reply Posted: 29 Aug 2008 at 3:22pm
	Have you tested this with your transmitter? IIRC, mono FM has a pilot tone at 19kHz and stereo FM adds a L-R difference signal at 38kHz. In order to prevent the incoming audio signal from interfering with these signals (added by the transmitter) a low pass below 19kHz is typically applied to the incoming audio. In other words... a device like this is not compatible with every transmitter out there. The release notes show this device being introduced at after the audio is multiplexed (19kHz low pass already applied and 38kHz subcarrier already created)... do you know how to find this line and modify your transmitter accordingly? (This device is not just plug and play into your typical Ramsey/Belkin box... hardware modification will be required to tap the MPX signal). I believe we have a broadcast engineer in our midst that can correct anything I might have messed up... it has been a while since I studied RF from an EET perspective. It is an interesting concept and I will make a note of it, but this is not on the project plan at this point in time. Edited by LightsOnLogan - 29 Aug 2008 at 3:29pm


JohnnyL Members Profile Send Private Message Find Members Posts Add to Buddy List Pre-Order User Joined: 17 Dec 2007 Location: Merced Ca Online Status: Offline Posts: 67	Quote Reply Posted: 29 Aug 2008 at 3:10pm
	http://pira.cz/rds/show.asp?art=minirds_encoder ive got one these gizmos and would like to use it this season

LightsOnLogan Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Joined: 11 Oct 2007 Online Status: Offline Posts: 3187	Quote Reply Posted: 29 Aug 2008 at 3:00pm
	I was still scratching my head trying to figure out why someone wanted to connect to a SQL database with the depreciated RDS... that is the programmer in me. It just now dawned on me that this post might be referring to "RBDS" (Radio Broadcast Data System). If so, what transmitter were you planning on using that supports the 57kHz subcarrier and what interface does it have for reciving the data to transmit (this is not just a matter of the info simply being embedded in the audio signal)? Edited by LightsOnLogan - 29 Aug 2008 at 3:00pm


JohnnyL Members Profile Send Private Message Find Members Posts Add to Buddy List Pre-Order User Joined: 17 Dec 2007 Location: Merced Ca Online Status: Offline Posts: 67	Quote Reply Posted: 25 Aug 2008 at 6:48pm
	well, its a pretty cool toy and LOR II will support it eventually, hopefully this year so i dont think its going to far to inquire about Aurora's future goodies...

LightChristmas Members Profile Send Private Message Find Members Posts Visit Members Homepage Add to Buddy List Beta Testers Joined: 15 Oct 2007 Location: Equality, IL Online Status: Offline Posts: 993	Quote Reply Posted: 25 Aug 2008 at 10:23am
	Remote Data Services? Might be me being short-sighted, but why?


JohnnyL Members Profile Send Private Message Find Members Posts Add to Buddy List Pre-Order User Joined: 17 Dec 2007 Location: Merced Ca Online Status: Offline Posts: 67	Quote Reply Posted: 25 Aug 2008 at 1:08am
	do you have any plans support RDS?