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From: AMuzi <am@yellowjersey.org>
Newsgroups: rec.bicycles.tech
Subject: Re: For those who believe in electricity
Date: Wed, 9 Apr 2025 07:39:30 -0500
Organization: Yellow Jersey, Ltd.
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On 4/9/2025 5:53 AM, zen cycle wrote:
> On 4/8/2025 6:44 PM, Frank Krygowski wrote:
>> On 4/8/2025 6:29 PM, Frank Krygowski wrote:
>>> On 4/8/2025 5:15 PM, Frank Krygowski wrote:
>>>> On 4/8/2025 4:00 PM, Zen Cycle wrote:
>>>>> On 4/8/2025 3:04 PM, Frank Krygowski wrote:
>>>>>> On 4/8/2025 1:40 PM, Zen Cycle wrote:
>>>>>>> On 4/8/2025 12:44 PM, Frank Krygowski wrote:
>>>>>>>> On 4/7/2025 2:58 PM, Zen Cycle wrote:
>>>>>>>
>>>>>>>>> Just as a matter of personal interest, can you read 
>>>>>>>>> the numbers off the 16 pin IC?
>>>>>>>> It has no numbers or other codes at all! It's solid 
>>>>>>>> black with a sort of fine stippled finish.
>>>>>>>>
>>>>>>>
>>>>>>> Take another look. I can see 4 rows of text but the 
>>>>>>> resolution on the picture isn't good enough to make 
>>>>>>> it out. FWIW, it's the square device in your second 
>>>>>>> picture with 4 solder joints on each side, next to 
>>>>>>> the octagonal device with "220" written on it (that's 
>>>>>>> a 220uH inductor, likely part of a PWM or PS switcher 
>>>>>>> circuit).
>>>>>>
>>>>>> Sorry, Zen, it absolutely has no writing on it. I 
>>>>>> don't know if I can manage a micro photograph to 
>>>>>> convince you, but I'm using a high powered loupe in 
>>>>>> sunlight. It's just a stippled black finish.
>>>>>>
>>>>>>
>>>>>
>>>>> Try again, using this as a reference:
>>>>>
>>>>> https://1drv.ms/i/c/5c034a6b86a172e9/ 
>>>>> EX6snfFdTeJMl1tfB4xqOUwBXw_4YXVPsbTNjw04Bpgcdw?e=lFRSWg
>>>>>
>>>>> 4 lines of text. I think I can make out 4x35x on the 
>>>>> first line, but that's it.
>>>>
>>>> Those are reflections. There is no text, no letters, no 
>>>> numbers. I'll try to get a super-closeup photo later, 
>>>> but this is silly.
>>>
>>> Here are two more shots, through a loupe:
>>>
>>> https:// 
>>> live.staticflickr.com/65535/54440036155_e9437c6d58_m.jpg
>>>
>>> https:// 
>>> live.staticflickr.com/65535/54438807352_4bb9fb0d30_m.jpg
>>>
>>> Honest, no text, no letters, no numbers.
>> Here's a larger version of the better one. I think I 
>> clicked wrong before generating that link.
>>
>> https://www.flickr.com/photos/16972296@N08/54438807352/in/ 
>> dateposted- public/
>>
>> It does seem odd to have an unlabeled 16 pin device. I can 
>> check to see if that's some sort of coating applied over 
>> some text.
>>
>> ... Nope. Some fine black stuff scraped away, and the 
>> surface now looks smoother, but still no visible characters.
>>
>>
> 
> I don't know what to tell you except maybe get someone with 
> better eyesight to look at it. The First of the new photos 
> is a good angle, I can see the lines of text but still 
> blurry. The second and third of the new photos are a bad 
> angle such that the light doesn't catch the text, but better 
> resolution.
> 
> I know Jeff has already commented about seeing the text, I'd 
> be interested if anyone else has seen the photos and can 
> comment.
> 
> _All_ devices of this type are laser etched with the part 
> number and some sort of factory/lot/date code, or at the 
> very least with some type of abbreviated code that you can 
> decipher with the data sheet. Some companies _do_ have 
> devices custom built with no markings to prevent reverse 
> engineering, but those are rare and generally restricted to 
> higher dollar items.
> 
> No big deal. It was just a matter of personal interest, 
> don't bother putting anymore effort into it if you don't 
> want to.


A customer produces an industrial machine based on his 
father's design patent for which my customer (an academic 
electrical engineer PhD) makes up the controller boards. He 
scuffs the top of some chips and coats them with epoxy.

I can see where a manufacturer would request electronic bits 
with no number if it would otherwise reveal information to 
competitors but I don't think that's likely for  a bicycle 
lamp.  Not unreasonable for a $50K machine.

-- 
Andrew Muzi
am@yellowjersey.org
Open every day since 1 April, 1971