Zener Diodes Help

Thanks in advance if anyone is able to help.
Trying to help partner repair an Alpine Amp which was put through reverse polarity…
From what we’ve gathered, it looks like the Zener Diodes have been fried
Managed to identify the zener diodes per the service manual but we’re far from proficient in understanding the specs…
At the same time i dont believe these zener diodes are available anymore… so i’m guessing we have to find the closest equivalents in order to repair the unit…?

the Amp in question is an Alpine MRP-F300
The zener Diodes we believe to be fried are the following:


The following link is to my Adobe Document Cloud with the Datasheet to the HZL-L Series of zener diodes

This next link is the Service Manual for the Alpine MRP-F300…

If anyone could advise on a suitable equivalent available from Digikey or just any equivalent at all… that would be super helpful!



I would be very surprised if a few zeners were the only thing that let the smoke out in such a situation.

That said, the first things you’d want to look for in sourcing a replacement zener would be a device in a similar physical package, with the same Zener voltage. Items currently on hand matching the package should be accessible here. The ‘15’ in the P/N would point in the direction of a 15V device nominally, ‘16’ a 16V, etc. Looks like the original part series may have been sold sorted with a finer gradation of test voltages than usual (grade 1, 2, etc.) which you’ll probably have trouble finding; it’s a bit akin to a grocery store selling a 5 pound bag of flour, but as separate items depending on whether the bag weighs 4.995 to 5lb or 5 to 5.005lb. Haven’t digested the design enough to know if that would make much difference or not, but if it does, by the time you bought enough to sort through in hopes of finding one that matches, you’d be getting close to the cost of a replacement unit.

Honestly, unless you’ve got some skill at electronics test & repair you’re probably better off replacing the unit. Just replacing parts that look burny probably 'aint gonna do the trick, and if you don’t replace -all- the stuff that’s broken, you run a risk of toasting new ones that you’re putting in. If you’re in it for the learning experience though, it could be a worthwhile effort.

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