I’m trying to fix my friend’s Proton 440 FM tuner that only plays through one channel. I traced the signal to this component. Since both channels have this Low Pass Filter in their path, I swapped positions and now the opposite channel does not work, but the one that didnt work before, does now. I measured across the input and output of the bad one and it is completely open. The working component reads about 45 ohms or so. I have not been able to find much of any information about it. I have a service manual and it describes it as FM MPX LA1196. In the schematic it is labeled as LPF 301, hi-lited in pink on the attached picture. Most of what I have read suggests trying to fine an old tuner to pull parts of but I have been unsuccessful at that so far. I also read that some can be jumpered across and it might work, but this gives a pronounced hum on the faulty channel with no other signal when I try.
With this in mind, I decided to try the experts and see if some of this information helps to identify the characteristics of the component and see if there might be alternatives I might be able to try.
Thanks
Hello,
Welcome to the DigiKey TechForum. I searched for possible alternatives and wasn’t able to find anything to offer for this part. Pulling parts from another device may be the best option for a repair in this case.