Cheap UV EPROM Eraser Teardown and Spectrum Analysis

In this video, I did a quick teardown of a cheap made-in-China UV EPROM eraser and measured the spectrum of the UV tube using a monochromator. www.kerrywong.c...
www.kerrywong.c...

[@stude1965]

I have one of these erasers and I couldn't get a M27C801 completely erased after multiple tries. I took a mirror from a car sunvisor and glued it to the inside of the top above the bulb thinking it would reflect more light downwards. It worked!

[@marcofelicani4307]

i had some problem, too!

[@loicduwelz1659]

Thank you. Exactly ALL the info i was looking for before buying one. Mercury lamp, timer, electronic ballast, even spectrum of the light. I can now buy one safely ;)

[@KerryWongBlog]

Great!

[@andycraig7734]

Thank you for the video. Is that bulb one of the types that should be cleaned of skin oils after touching?

[@MatsEngstrom]

I feel silly for commenting on a 7 year old video, but how the heck could the power consumption in "standby" (when the power was cut by both the switch and mechanical timer) be two watts? Must be some major leakage in the switches then ;-)

[@alien8r33d]

I had one of those and I noticed that when I slid the draw out, it felt like it was catching on something so I opened it up. In mine the draw was retained by a self tapping screw through a slot in the plastic, which prevented the draw from being pulled right out the front of the unit but it was slowly sawing through a track on the underside of the PCB which was carrying live mains. Stripped and binned.

[@KerryWongBlog]

Mine has a tapping screw to prevent the draw from being totally pulled out as well. Yeah, if wire was caught it could be damaged overtime.

[@alien8r33d]

Not a wire, it was a track on the PCB.

[@pyt22fr11]

Excellent video, thanks !

[@geezberry8889]

you forgot to give your verdict on whether this is a good product\design and if people should buy it

[@fausergustavo]

the diferency can be because boncing on plastic parts ???

[@KerryWongBlog]

It could, I should test it again directly against the UV tube. I would need to somehow reduce the intensity as the light is too bright for the monochromator and would saturate the output.

[@fausergustavo]

Kerry Wong , i dont know if its possible .. but you coud probe directly but a litte far from the lamp ... so the intensit will be less then it would be near ... and from the that we can calculate the real power ...

[@davidgaleski5303]

thank you

[@KerryWongBlog]

You are welcome!

[@ubaidullahubaidullah4936]

Thnks

[@EdwinNoorlander]

Does it work on 240v AC?

[@KerryWongBlog]

I haven't tried, but the ebay site did say 110-240V and @vladabuba below did say he got it working under 240V.

[@joeambly6807]

Are you related to Amy Wong on Futurama? :)

[@KerryWongBlog]

No :-)

[@CAHSR2020]

Looks like you came to the Wong place for Amy.

[@vladabuba]

I have bought the same model from ebay. But after pressing 'On' and setting timer, I do not see any light. Not even purple light from device hole as in your video. Is my unit faulty? I received it brand new - but it looks dead on arrival :( ... Also I'm using 220V as I'm in Europe, but in description on ebay it states that it supports from 110-240V...

[@KerryWongBlog]

Yes, looks faulty to me. If it's not economical to return you can always fix it yourself, as long as the UV tube is intact. It could be just a loose wire somewhere.

[@vladabuba]

Thanks for reply. Had contacted ebay seller and then had opened uveraser myself. Yes, it was faulty - mechanical timer was broken. Just had disconnected wires from timer and then bonded them together and now eraser works fine ;) How much time it takes to erase eproms? (mine is ST M27C64A)

[@KerryWongBlog]

Mine took around 15 to 20 minutes.

[@papalevies]

Do UV erasable eeproms still get produced?

[@KerryWongBlog]

Oh yes, you can still buy them brand new.

[@glenslick2774]

Who still produces UV erasable EPROMs? The only EPROMs I currently see listed at Mouser and Digi-Key are Atmel / Microchip OTP plastic DIP parts. I don't see any windowed ceramic parts from them or any other manufacturers such as STMicroelectronics.

[@CAHSR2020]

He must be talking about old-new stock?

[@andycraig7734]

I found a M27C322 EPROM on eBay made in 2011. 23rd week. ST brand. Singapore