weedeewee wrote on 2026-02-25, 16:38:

When you go for something LED based it's good to know that if the LEDs aren't in a metal case that they won't produce the good UV for erasing the eproms.
the reason for them being in a metal case is that the UV also destroys the plastic casings.

I'm using a UV sterilizer with LEDs in a plastic case and it works for erasing EEPROMs.

I wouldn't necessarily assume that just because it is LEDs in plastic that it won't work. It really depends on the type of LEDs themselves.

Ozzuneoj wrote on 2026-02-25, 07:41:

What if you use a magnifying glass to focus sunlight on the photo-sensitive window? Would that wipe them fast? 🤣

No, at least with normal (soda–lime) glass - it blocks UV.

So, I'll have to buy some kind of second-hand gadget sterilizer with UV-C light, because sun exposure for moths is not an option.

Grzyb wrote on 2026-02-26, 03:39:

Ozzuneoj wrote on 2026-02-25, 07:41:

What if you use a magnifying glass to focus sunlight on the photo-sensitive window? Would that wipe them fast? 🤣

No, at least with normal (soda–lime) glass - it blocks UV.

I think there's more effective ways to literally burn the EPROM chip, than using the sunlight + magnifying glass 🤣

BTW, you have a nice profile picture 😀

For an old job I had, I had to erase thousands of EPROMs. I used the same basic UV eraser that is everywhere on Aliexpress, like this one:

https://www.aliexpress.us/item/3256807473408653.html

It's the best tool for the job. Never once had an issue, and it's quick and cost less than $15.

jh80 wrote on 2026-02-26, 04:50:

For an old job I had, I had to erase thousands of EPROMs. I used the same basic UV eraser that is everywhere on Aliexpress, like this one:

https://www.aliexpress.us/item/3256807473408653.html

It's the best tool for the job. Never once had an issue, and it's quick and cost less than $15.

This is the one I had that came with pieces falling out of it. I've just read so many bad reviews about them failing or the bulbs going bad (burning) quickly I didn't want to try another. It's frustrating, because I'm sure they do work when they aren't broken.

I guess you could purchase a 254nm LED and point it at the erase window

Ozzuneoj wrote on 2026-02-26, 04:53:

This is the one I had that came with pieces falling out of it. I've just read so many bad reviews about them failing or the bulbs going bad (burning) quickly I didn't want to try another. It's frustrating, because I'm sure they do work when they aren't broken.

Yeah, you have to play the Aliexpress lottery, but the reviews are generally high.

I imagine if you're only needing to erase an EPROM once in a blue moon then it might be tempting to try other solutions, but if you're doing something with arcade boards or something like that where you've got to erase a bunch of chips frequently, then it's worth ordering some until you get a decently built one.

Shponglefan wrote on 2026-02-25, 15:14:

I use a UV sterilizer designed for pacifiers. It is a little awkward since it has a set timer, so i have to repeatedly reset it to fully erase an EEPROM. But it does work.

The attachment Sterilizer 1.jpg is no longer available

The attachment Sterilizer 2.jpg is no longer available

You can just wire up a bench PSU to the traces for the LED to bypass the micro controller's timeout 😀 I would've kept the overall PCB if I hadn't accidentally put 15 volts into it and burned out the other LED.

Here's my 3d printed EPROM bracket to hold an up to 32-pin ROM in place over the LED - the arm has a hole in the middle so you can line up the LED with that hole to get the bracket in the right place.

I use a toothbrush sterilizer