Hello, I’m looking for a suitable replacement for a zener diode in a Technics SA-600 receiver. The service manual states the part number is SVDMZ424B but doesn’t offer any specifications beyond the circuit diagram. Hard to see, but appears to have “Z24” marking. Red with black band towards one end, and a small silver band. Pretty beefy legs and body compared to other zeners I can see on the board.
Reason for replacement is indication of heat damage on the PCB right near the diode, so anything that would be an upgrade would be great.
Thank you!
Hi ripneck
I am not able to locate a datasheet or specifications for part number SVDMZ424B. Without a datasheet or knowing the specifications for the part, I am not able to offer an alternative.
Based on this from the SA-600 service manual, I agree that it’s almost certainly a 24V zener diode.
Additionally, in this manual for the Technics SU-V4X, calls the SVDMZ424B a 24V zener diode.
It is being used to prevent a voltage spike from occurring when the relay coil is de-energized. I don’t know what the power rating is based on the given information, but larger will generally be better. It would make more sense, in my opinion, to use a TVS (basically a zener diode designed to clamp voltage and dissipate a lot of power for a short period of time). I would recommend using one of these TVS diodes for that purpose.
1 Like
