K-40 Panel

[Custom_Creations]

Here is my K-40 panel for now. I did not get all the parts in that I want to use but here it is so far. Nothing special.

[NedMan (Ned Hill)]

Nice. Are you using two tone acrylic or painting the engravings white?

[Custom_Creations]

Paint. Too poor to get 2 tone… LOL

[NedMan (Ned Hill)]

Nothing wrong with paint, it’s what I did with mine. Used silver calligraphy ink, makes it sparkle a bit

[Custom_Creations]

What is the Pot. (V) part and how is it connected?

[NedMan (Ned Hill)]

Ah, excellent question That’s a voltmeter measuring the voltage between the In and ground pins on the potentiometer. The voltage is directly proportional to current so I can just turn the pot to a voltage.

Digital Control Panel and Tube Current

So the HVT on my LPS went and did a zombie on me. Since I needed to replace my LPS I decided it was time to do a bunch of upgrades I’ve been sitting on. In addition to the LPS I also replace the tube (2.5yrs original). Also wanted to get rid of the digital control panel and go to a potentiometer and ammeter so I can see how much current I’m actually running. @donkjr was big help in getting me going on this upgrade. To make the transition I did a series of measurements . With the new tube…

[NedMan (Ned Hill)]

More discussion here

Ned's control data drove me to distraction

I had the notion of characterizing the operator control of the K40 LPS on my to-do for some time now. Then @NedMan goes ahead and does a stellar job of capturing just that! I couldn’t hold back my curiosity and just had to build some math models. I captured this musing in a blog post. Perhaps someone else will be equally thrilled to get a glimpse at these models… or not

[Custom_Creations]

Oh, ok. I have a bunch of those I used for vape mods

[NedMan (Ned Hill)]

Yeah it’s a 3 wire meter pulling off the 5V on the power supply to read voltages below 3V.
Wiring diagrams here:

Replacing the Digital Panel with an Analog one

This post links to a blog post that outlines the process of converting a K40 with a Digital Panel to one that has analog controls and display. This post provides: Instructions Schematic Pictures Panel Layout This conversion was a collaboration with @NedMan (https://donsthings.blogspot.com/2019/02/replacing-k40s-digital-panel-with.html)

[Custom_Creations]

This is the style I have. No docs for it. Lol.

[donkjr (Don Kleinschnitz Jr.)]

Gives you an accurate pot position by reading the IN voltage. This way you do not have to have graduations.
It’s a value of 0-5.

[Custom_Creations]

Here it is installed.

[funinthefalls (Anthony Bolgar)]

Looks good!

[donkjr (Don Kleinschnitz Jr.)]

Very sharp nice job!

[Custom_Creations]

Thanks! Now to control the Z with Easy stepper and some type of small Arduino board…