Defective 74HC165 Shift Registers

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Alpes Machines is very sorry and presents his apologies :

It has been discovered that some 74HC165s from the first batch are randomly defective (certainly a factory bad batch : 44EJ3HKE4) after several hours of use. The sourcing has been changed since. Here is a screen shot :

 

It’s strongly advised to use DIP16 sockets for those shift registers in order to swap them for new ones when needed, in the future, or to change them now for brand new ones.

Mouser’s part : 595-CD74HC165E

They are easily available worldwide in electronic components stores or on the internet (#74HC165 ) for a few bucks (or you can ask us some samples).

The serial out shift registers 74HC165 are used to “decode” the buttons press. So if you discover that the buttons are not working correctly, it is certainly the fault of ‘165s.

./..

But now that you’ve discovered that the shift registers are faulty, what to do ? Well, you need to remove them. We will sacrifice them and replace them for a DIP16 socket + brand new 74HC165. Ideally you would remove them with a desoldering station.

If you don’t have a desoldering station, there is an efficient process :

  • Remove as much as possible the solder
  • Cut the legs to remove the body of the shift register
  • Remove the leg of each hole
  • Clean the holes

 

You will need the following tools (especially desoldering wick/braid) :
Use the braid to remove as much as possible the solder from the pads, softly pushing with your iron (set on 320°C), first from center and, then, from the sides to the center of the component, on the BOTTOM side of the PCB.
Then you cut the leg by pushing on sides of each adjacent legs to force the tweezer between the legs. Be as possible at the vertical, and start on leg 1 (the slimmest).

Then, while heating the pad, you remove the resting leg by pulling it with a tweezer.
Now just clean the holes using the bread, ideally by not ironing the center, but just around the hole as the rest of solder could melt and close the hole. Don’t apply too much pressure as the heat would deform the pad. You can cut the braid at 45° to insert the end of the wick inside the hole, or use a resistor leg as a wick at the very end :

Check in the light that each hole is circular and properly cleaned. Then solder a DIP16 socket, insert the new shift register and it’s done.

 

Sold Out

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Dear fellows,

The first batch of Matrix Ctrlr is sold out. I will restock 10 more kits end of next week : you can preorder them by using the normal procedure in the paypal listing. I would ship them when ready.

 

Once this small run sold out, i will launch another batch, with price drop. Options should evolve too (extension, alternative firmware Eprom, assembly service). Waiting time should be around one month, corresponding to the necessary delay to restock all parts, panels, overlays and components.

Cheers

Matrix Ctrl kit stock is low

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THANK YOU !!!

Only 4 Mainboard PCBs in stock ! Expect at least 10 days to restock.

Extension is SOLD OUT ! idem : 10 days.

The rest is OK for the moment. Critical items are front panel and overlay (one month delay both).

There are 4 units soldered and built for those interested by mounting service.

 

 

PS : OS is currently 0.97d with major features and enhancements.

Assembly service for Matrix Ctrlr kit

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According to Facebook traffic and analytics, the Matrix Ctrlr shows great interest.
Unfortunately, lots of you seem refreined by the fact of building it despite it has been conceived from the beginning to be as simple as possible.

So, those interested by a Matrix Ctrlr (fully built) can comment this post to give me an estimate. I would then consider if i am proposing an assembly service in the Shop.

Thanks for your interest ????