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-   -   IC Marking (https://www.vintage-radio.net/forum/showthread.php?t=160599)

Wendymott 16th Oct 2019 1:29 pm

IC Marking
 
2 Attachment(s)
Hi Peeps..... Please do not think I am telling you erstwhile members how to suck eggs... but it occurred to me today, the difficulty of reading some IC markings, in my case with a bench magnifier AND a monocular eye piece.
I had just bought some 8V and 9V 3 pin regulators.
With minimal storage space left to segregate these items.."Light bulb" moment.. felt tip pen..it will not harm the thermal properties...
Thus they are combined in one sector without confusion

Nuvistor 16th Oct 2019 1:37 pm

Re: IC Marking
 
Nice and neat.

I find if something is too small to see the writing I take a photo with the phone and enlarge it, usually works without any eye strain. All done in the phone.

Argus25 16th Oct 2019 2:00 pm

Re: IC Marking
 
A really useful hand tool to have on the electronic workbench is an Otoscope.

These were designed to be inserted into the external acoustic meatus to view the Tympanic membrane. They provide a glare free lighting and a good level of magnification with a magnifying lens over the viewing window.

Typically they run from 2 AA cells (the cheap ones) and have either an LED illumination or a "lens end bulb" in them. They provide a great hand tool to use to pick up to examine IC, markings or other surfaces, for many repairs/inspections. I discovered this more or less by accident, that they were a great electronics workshop tool, even though not intended for the application.

The prices of these have dropped down really low over the years, I just looked and saw one like this:

https://www.ebay.com/itm/Mini-Otosco...IAAOSwOxJdn39V

But there must be many more examples on the usual auction sites.

G8HQP Dave 16th Oct 2019 2:34 pm

Re: IC Marking
 
Yes, I often struggle to read tiny mid-grey or brown writing on a dark grey background. I find that a magnifying glass and daylight can help, and find the best orientation by experiment.

Nickthedentist 16th Oct 2019 3:00 pm

Re: IC Marking
 
I agree.

The digital macro function on my 10 year-old Canon compact camera is amazing. The same model can be had for a fiver on eBay now if you're lucky.

The direction of the lighting is crucial too. I find shining my LED dental curing light almost along (rather than perpendicular) to the surface, then using the macro on the camera gives easy to read results almost every time.

N.

G6Tanuki 16th Oct 2019 3:11 pm

Re: IC Marking
 
Ultra-violet light (from one of those handheld 'fraudulent banknote detector things shops used to have a few decades back) can also provide a useful reveal.

[This sometimes helps too with the faded writing on valve envelopes].

AC/HL 16th Oct 2019 4:23 pm

Re: IC Marking
 
Search UV torch on eBay or Amazon

Wendymott 16th Oct 2019 4:31 pm

Re: IC Marking
 
Thanks for the comments and recommendations peeps

Diabolical Artificer 16th Oct 2019 7:45 pm

Re: IC Marking
 
Good idea Wendy, I sometimes use my daughter's nail varnish to mark different hfe on trannies like BC456A/B/C. She gets lot's as unwanted gift's in myriad colour's, saves lot's of different bags; just have to mark the bag with a little key, EG red A, blue B, green with sparkles C.

"A really useful hand tool to have on the electronic workbench is an Otoscope." I agree. I got mine out of a hospital skip years ago. It's great for seeing in out of the way corners, checking down holes etc.

Polaroid glasses can help ID hard to see IC/tranny numbers too, just a matter of getting them at the right angle.

Andy.

Maarten 16th Oct 2019 11:51 pm

Re: IC Marking
 
I use an older version with glass lenses of this pocket magnifying glass: https://www.opticsplanet.com/zeiss-o...ifier-d36.html

I do agree that the macro setting on a camera can be very useful as well. I have one that performs decently under low light conditions.

Oldcodger 17th Oct 2019 12:25 am

Re: IC Marking
 
These days when I keep them in a bag and mark the bag for type. For singles I use a Sharpie pen and mark the type on the TAB(e;g 7805 or +05with the current suffix) when I get them.
Helps if you have a mix of both + and - regulators. As + and - terminal regulators have differing pinouts, you could also mark the tab with +/-05( current suffix) and mark the common with black ink at the top.
For a quick voltage check, I use an old Panasonic 4 pin connector with wires connected to the socket and a meter on the output. A 78/79 device plugs nicely into this and it's quick and easy to check the device.


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