I am capturing the schematics of the video circuitry related with the generation of the video composite signal (i.e. around the MC1377 PAL/NTSC encoder).
In situ, that's this part (taken from my series of shots of my motherboard) :
There are 2 components that I cannot define completely : DL1 and L403
What I could infer so far, thanks to the datasheet of the MC1377 :
- L403 seems to be a passband filter, consisting of tuned coils. The datasheet has a sample application circuit mentionning such device from TOKO. And I could find somewhere some kind of catalogue/datasheet that look alike the component on my motherboard and with the same number of pins like suggested by the schematics. But I could not find any other details, namely the frequency range, from the marking on the component.
- DL1 seems to be a "Delay line" (there is a builtin symbol on kicad too). Again, nothing about the delay introduced, and I got nothing by looking for further data using the marking.
So my questions :
- Please confirm that L403 is a passband, and DL1 a delay line ; or please teach me if I'm wrong.
- What are the parameters of each of those two components ? And it seems that it depends of the target system (PAL or NTSC).