nice video about kosbo clock

[Franck Pissotte]

only for french understanding people
https://www.youtube.com/watch?v=JTqkxA22mJs&feature=em-subs_digest

[gregebert]

Nicely built, but the wrong schematic was shown because the upper PCB uses HV5122 parts, and the schematic showed K155D.

My only concern about using socket pins in this case is that they were already soldered to the board, so plugging-in the expensive IN-18's may subject them to stress. I individually numbered mine, slid the socket pins onto the tube,  THEN soldered in-place; the socket pins are custom fitted to each tube and there's almost no stress on the tube. I also 3D printed pin collars, though they are mostly cosmetic.

That IN-18 with the 9110 date code must have been one of the last few built....

No heat-sink on the MOSFET, and could probably use a few more mounting holes [Did you notice the display burped when the PCB was wiggled ?]

[Alic]

He says in the video that the HV5122 is compatible with the SN74141/K155ID?

I feel the same way about the pins, having already killed an IN-18 this way :-(.

Unfortunately Kosbo only sells his IN-18 clock fully assembled without the tubes afaik.

I'm also partial to heatsinks to prolong the life of the components and the surrounding PCB areas as much as possible, especially when there isn't an apparent ground plane to help dissipate the heat.

[gregebert]

The HV5122 is a completely different animal than the 74141/K155; it has a built-in shift register which seems to be a common, and very useful feature of the HV55xx device family.