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EDA => General PCB/EDA/CAD Discussions => Topic started by: Chris56000 on May 14, 2021, 08:04:59 pm

Title: Elektor PCBs – can JLC make them this style?
Post by: Chris56000 on May 14, 2021, 08:04:59 pm
Hi!

Attached is a layout drawing of a modern Elektor PCB where the track is in black on the top side of a green background, from the colour–printed era of the Magazine.

Is it still possible to get a PCB made by JLC, PCB Way, etc., to this style with the black tracks on top, if so, how is it done?

I know JLC can handle TTF on silkscreen as they've made two PCBs for me with "Radio Constructor" Magazine silkscreen lettering!

Chris Williams
Title: Re: Elektor PCBs – can JLC make them this style?
Post by: thm_w on May 14, 2021, 08:33:26 pm
JLC will not do this.

But any sort of regular fab could likely do a similar looking piece if you ask for a one layer board with two color silkscreen. Black first then white overtop.
I'm also quite sure this photo is a photoshop creation/screenshot and not an actual board.
Title: Re: Elektor PCBs – can JLC make them this style?
Post by: ataradov on May 14, 2021, 09:18:28 pm
I'm not sire I understand the request. The visual effect shown on the picture is easy to get - it is a single layer PCB with tracks on the back side and silk screen on the other side. One of the sides has green solder mask. No copper pours, of course.

If you light that PCB from the back, it will appear exactly as shown on the picture.

If you want it to work without the light, then you have to duplicate traces and do a double color silk screen. None of the cheap prototype services will do that. But I'm sure they will do it for the full price.
Title: Re: Elektor PCBs – can JLC make them this style?
Post by: TK on May 14, 2021, 09:31:40 pm
ataradov is right.  It is a single sided PCB and the black traces you are seeing are the bottom side of the PCB (you can see the letters in reverse).  The top only has white silkscreen and green soldermask.
Title: Re: Elektor PCBs – can JLC make them this style?
Post by: Chris56000 on May 15, 2021, 08:46:13 am
Hi!

Quote
If you want it to work without the light, then you have to duplicate traces and do a double color silk screen. None of the cheap prototype services will do that. But I'm sure they will do it for the full price.

Ah, that explains it!

I remember in my college days (40 years ago!) another student bought a ready made PCB from the Elektor Print Service that had a double layer silk screen, black was a top– side reproduction of the tracks and a white silkscreen component overlay on top – it also had red solder mask underneath on the copper side, I know JLC can't do that with red underneath and blue solder mask on top!

Mind you, in the 1970s and 1980s up to at least 2000, boards from Everyday Electronics didn't have any solder mask or silkscreen, you had to rely on having the original article with the assembly drawing to hand!

I know JLC will do me the TTF silkscreen, so I'll design my Elektor Style PCBs with the Elektor style components and the original "Microgramma" typeface for the component designators, then if at some future date we get a reasonably inexpensive service that offers two silkscreen layers and choice of solder mask colour on top & bottom I can make the genuine Elektor "full monty" from my student days!

Chris Williams
Title: Re: Elektor PCBs – can JLC make them this style?
Post by: nctnico on May 16, 2021, 02:59:09 pm
I'm not sire I understand the request. The visual effect shown on the picture is easy to get - it is a single layer PCB with tracks on the back side and silk screen on the other side. One of the sides has green solder mask. No copper pours, of course.
That is not the question. PCBs from Elektor (IIRC) usually have the traces as a black silkscreen on the component side with a white silkscreen on top. So two silkscreen runs.

This is another example: (https://www.uploadarchief.net/files/download/ps-2.jpg)
Title: Re: Elektor PCBs – can JLC make them this style?
Post by: dunkemhigh on May 16, 2021, 10:35:43 pm
I think they are correct. It seems very strange indeed to have two silks (although I can see the case for having the copper duplicated on top for 'education'), so I tried to find an example either way. What I managed to turn up was from here:

https://worldradiohistory.com/UK/Elektor/00s/Elektor-2007-01.pdf (https://worldradiohistory.com/UK/Elektor/00s/Elektor-2007-01.pdf)

On page 44 of that is a PCB exactly as you've shown - copper is black on the top. This is a double-sided PCB so that isn't the bottom copper  but the top copper.
(https://www.eevblog.com/forum/eda/elektor-pcbs-can-jlc-make-them-this-style/?action=dlattach;attach=1219856;image)

However, it's a fake PCB - a printout rather than a photo. Photos of the actual PCB are on page 45, and if you take a look at the top side you can see it's just normal resist-covered copper.
Title: Re: Elektor PCBs – can JLC make them this style?
Post by: ataradov on May 16, 2021, 10:48:19 pm
This only works for a single sided PCB anyway. So why not just duplicate the copper artwork on both layers? It will not be as visible, so you may need to play with the color of the solder mask, but it would be much easier and cheaper than multicolor silkscreen.

Transparent solder mask may be the most visible. It will look like the yellow PC motherboards popular in the 90s and yearly 2000s.
Title: Re: Elektor PCBs – can JLC make them this style?
Post by: srb1954 on May 17, 2021, 12:11:59 pm
Hi!

Attached is a layout drawing of a modern Elektor PCB where the track is in black on the top side of a green background, from the colour–printed era of the Magazine.

Is it still possible to get a PCB made by JLC, PCB Way, etc., to this style with the black tracks on top, if so, how is it done?
This looks like a drawing rather than an actual photograph of a PCB.

However, you can get this effect of the black tracks by specifying "black oxide" finish on your PCB. This converts the surface layer of the copper to black cupric oxide. This is normally used for internal layers of a multi-layer board to improve the adhesion of the fibreglass prepreg to the copper layers.

In the past I have also seen black oxide applied to the outer copper layers of double-sided PCBs to improve adhesion of the solder mask to the copper tracks.  I haven't seen black oxide finish on PCBs for many years so I assume the the formulation of solder masks has improved sufficiently that black oxide is no longer required.