I purchased a CZH-T501 transmitter and have attempted to use the RDS port on the back. I am able to get RDS to go through to the radio but the sound is distorted and high pitched with no bass or mid range. I have tried to use the pre-emphasis settings in breakaway broadcast processor and stereo tool, but it never sounds right. Am I correct in my assumption that this port is for RDS only and not designed as a multiplex port for proper audio? I am able to encode the stereo but the sound is too high pitched. Is there a way this can be fixed?
I was able to get the RDS to work through the regular line in with normal sound, but this transmitter sounds absolutely terrible. The sound is so lack-luster and muddy. I had a cheap $100 transmitter that competed with commercial radio stations but the output final finally died. Hence, I bought this expensive unit but it sounds so bad. Comparing it to cmmmercial FM audio is a comedy act. Is there something wrong in my audio chain or is this just a POS?
Checking the manual which doesn't have much information looks like it suggests the port is for RDS/SCA only. If that is the case then it's possible there is built in filtering on that to only pass the frequencies needed for RDS. Passing RDS through the regular audio jacks may be a bad idea if they are also filtered to only pass audio frequencies. Doing so would probably distort the transmitters built in audio limiter or something else. I would run the unit without any RDS enabled and see if that helps.
Would you recommend using a separate sound card for RDS and can you recommend a simple program other than Stereo Tool to send RDS text to an output? I'm currently using stereo tool as a dst plugin and multiple instances running at the same time tend to cause problems.
Would you recommend using a separate sound card for RDS and can you recommend a simple program other than Stereo Tool to send RDS text to an output? I'm currently using stereo tool as a dst plugin and multiple instances running at the same time tend to cause problems.
Thanks
I honestly have no idea with the software side of things. My guess is that using a separate sound card would get the trick done. If you have another computer laying around you can just use that into the RDS input to verify that it solves the issue. I played around with Airomate RDS software some time ago and it seems to be suited for this kind of usage if I remember correctly. If Stereo Tool has the ability to send the RDS out to a separate sound card then that would be all you need. What I find odd is that the transmitter doesn't have a standard MPX input and instead separates the RDS/SCA from the audio. I suppose in some station setups it would simplify things.
Thanks for the reply Kage. However, I found the RDS port to be basically useless. It introduces all kinds of high frequency static and noises/beeps from the computer into the audio chain. I ended up using a separate, standalone instance of Stereo Tool to send the info to the main sound card. I then have breakaway running with instance of Stereo Tool as a dst plugin. This takes care of the stereo widening and audio processing. Hence, I now have processed audio and RDS going into the main inputs of the transmitter from the same sound card. This seems to work very well.
I now have a pretty sweet setup using a very nice ground plain antenna, a 12 db attenuator and the transmitter loafing along at the 0.0 watt setting. SWR is damn near flat 0. The signal goes about halfway down my street. Just enough for a decent signal around my house but not enough to attract major attention (hopefully).
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