Page 1 of 1

CZE-T251 modification to modulate full MPX spectrum and RDS subcarriers

Posted: Sat Mar 21, 2026 4:55 am
by Admin
When I bought CZE-T251, I noticed that this transmitter cutting audio spectrum after 15kHz.
After I open it I found that it contains BH1415F chip

Image

This chip has integrated filter that cut everything after 15kHz, and I decided to turn off this filter by removing two capacitors on modulator board. You can find this chip under metal shielding plate.
Here is the picture after modification done.

Image

After that modification it started to pass through full MPX signal and RDS subcarriers.
Note: Don't forget to turn off stereo on your transmitter!
Any questions? Feel free to ask here.