Yet another resistance decade box

[JacquesBBB]

On One of the external holes, there is a pin that has been melted to hold firmly the board. Just cut the top part as close to the board you can ( i do it with a sharp wire side cutter).

Then press on the other side starting with the side with no pins. It should come now easily.

Do not break the pins. They will be useful to hold firmly the new board.

To put the new boards you need to be sure they are completely engaged on the pins. This needs some local pressure, they will snap nicely.

[mrjoda]

check this. It is easy

https://youtu.be/6eoKMs7ws6U

[nikifena]

Finally I finished my decade box.
The enclosure is made from 1mm sheet metal.

[Alex Nikitin]

Finally I finished my decade box.
The enclosure is made from 1mm sheet metal.

Looks good! However, a couple of suggestions:

1) Connecting a metal box to one of the terminals might not be a good idea if you plan to use the box as a resistor substitute in a live circuit. IMHO either the box should be plastic with an internal shield or a metal with a separate connection to the case (this also would provide a nice reduction in the stray capacitance across the resistors stack if the box is grounded separately).

2) You've connected the case to the high resistance end of the stack. This way the parasitic capacitance and leakage across the high value resistance is maximized. It makes more sense to connect the case/screen to the lower resistance side if you don't have a separate connection for the case.

Cheers

Alex

[nikifena]

Thanks for your suggestions Alex.
I will use for testing multimeters or if I need a variable resistor in some situations. The highest resistance values are to check the maximum measured capabilities of the DMM.

Yes, you are absolutely right! Grounding the isn't the best idea which I made Unfortunately there is not enough space for a switch. I will leave the existing box as is, but I will keep in mind about your recommendations in the future

Thanks again

[ivaylo]

Finally I finished my decade box.
The enclosure is made from 1mm sheet metal.

Goog job, Niki! You didn't say how. you produced the metal box from the nice drawing you posted before...

[nikifena]

Thanks ivaylo. I'm making electronic devices and have good experiance with sheet metal work. I made all of my enclosures 3D and then I send the files for production in my town. The process is pretty simple - laser cut, bending on a press brake and finaly powder coating. Because this is only one enclosure I prefer to place labes made with transparency foil printed with laser printer, but silkscreen is much better for mass production and gives much higher quality looks

If you guys like this enclosure, I can make similar like this one in a small batch. The price will be about 12-15 Euro imho.

[Back2Volts]

Finally I finished my decade box.
The enclosure is made from 1mm sheet metal.

It looks great!   Did you actually build the box yourself ?     

[nikifena]

^ I made all necessary sketches for fabrication, but I use few local companies to produce the enclosures.

[ebclr]

I used a hot hair, on the plastic pin, instead of cutting, On this way I can remelt after change the board

[Leo Bodnar]

Where is the link where you buy these kits from?
Leo

[ebclr]

Isn't a kit , was a group buy for the PCB and resistors only, I'm not sure if still available

[Mr. Scram]

Isn't a kit , was a group buy for the PCB and resistors only, I'm not sure if still available

It's open, right? So making more shouldn't be too much of an issue.

[Leo Bodnar]

Somebody please make them and stick on their web shop. 
This is impulsive buy thing-o like mints at the checkout, not something most people would spend a week reseraching and then wait for a month to arrive.
Please?

[ebclr]

"It's open, right? So making more shouldn't be too much of an issue."

Make yourself

[Mr. Scram]

"It's open, right? So making more shouldn't be too much of an issue."

Make yourself

Why so terse? I wasn't suggesting anyone specific should make them, I'm just saying making more is possible without having to steal the design.

[Fortran]

I've still got a lot of PCB's laying around.
You're welcome to buy as many as you want.

But supplying resistors is a bunch of work, so I'd need to up the price a lot on those.



Edit: I've got about 200 pcb's left, and enough 1% resistors for all of them.
It's the 0.1% resistors that's annoying to source in quantity.

[Mr. Scram]

I've still got a lot of PCB's laying around.
You're welcome to buy as many as you want.

But supplying resistors is a bunch of work, so I'd need to up the price a lot on those.



Edit: I've got about 200 pcb's left, and enough 1% resistors for all of them.
It's the 0.1% resistors that's annoying to source in quantity.

Can you give a ballpark price?

[Fortran]

6 PCB's = 1.50 USD
1% resistor kit = 2 USD
Shipping worldwide  = 3 USD


Edit: All gone

[bitseeker]

Wow, I didn't know you still had that many, Fortran. Glad to see new folks are interested in them.

[Fortran]

Many?
Considering how many I ordered, I'm scraping the bottom

[Leo Bodnar]

1% resistor kit = 2 USD

How much is for 0.1% kit?
To put it into perspective $2 is 12 minutes of unskilled labour in the UK (i.e. barely navigating into resistors section on Farnell)

[Fortran]

I dunno.  30 USD?
If there's a craze for them (again) I could go a lot lower, but they are expensive so I don't want to order unless I know I can sell them all.

To put in perspective, I bought a reel of 1% for the price of a set of 0.1%

[Leo Bodnar]

To put in perspective, I bought a reel of 1% for the price of a set of 0.1%

Heh, i have recently bought a single 0201 resistor for the price of a full reel of 1%
http://uk.farnell.com/1714024

[Fortran]

Then you know why I'd rather sell the stuff I have in stock