Adapter Box for (all) your Lab needs

[dangrie]

Hi,

I just wanted to show off and get feedback on my latest Project that I cobbled together in the last 2 Days. It is a "universal" Adapter Box that simply gives multiple connection points with the most common connector types seen in a lab environment.





The complete thing is highly inspired by the "Monsieur Adapteur" by felitek.de which appeared in EEVBlog #606. I wanted to have one, but sadly the Project is discontinued. Although all Files are available for this Project, I had some trouble sourcing some of the used components, so I spun my own.

I was surprised to not easily find 100 similar projects, so I wonder I you know of any? Also: What do you think of the Layout, Connector choice, and other design decisions? I would be happy to get some feedback before ordering the first set of Boards. Think something like this is useful?

All resources and documentation can be found on GitHub: https://github.com/dangrie158/AdapterBox/blob/master/README.md

[t1d]

I think that is rather neat and well done. You might swap places, with the BNC and Banana Socket sections. This would put the tallest component in the middle, giving better access to the lower Banana Socket components.

Also, you may want to use the multi-connection type Banana Sockets. They provide more attachment options.

Both of the Banana type connectors, the single and multi, can be directly bolted to the PCB. You just need to create big pads, for the post nut to seat on and make contact. No need, for the wire washer, or soldering. I added a layer of solder, to the pad, to give it extra strength, so the nut would not scrap it off. Here's the idea...

When you are bolting on the multi-connection type Banana Sockets, raise one of the plastic nuts and insert a small screwdriver, in the post's side-hole. Tighten the plastic nut, just with very slight hand pressure. Use the screwdriver to hold the post's hole in the proper direction, to allow access, when in use. Then, tighten the securing nut. Repeat, for the other posts. You will not need the backing plate.

I am sure that you know that Banana sockets pair holes are set on 19mm centers.

[Dave]

Personally, I don't see it being useful in any scenario.

If I need to connect something, I'd rather just crimp a couple of connectors onto a cable than have a bulky box sitting on my table. Most of the time you need more than 2 wires anyway.

The BNC on there seems pointless, because you're not going to maintain the characteristic impedance with this thing.

[Richard Crowley]

If I need to connect something, I'd rather just crimp a couple of connectors onto a cable than have a bulky box sitting on my table.

With something like this, you don't have to stop and get the connectors and crimp them on.
With something like this, you don't have to waste a couple of crimp connectors for something temporary.

Most of the time you need more than 2 wires anyway.

The concept is applicable to to a large number of wires.

The BNC on there seems pointless, because you're not going to maintain the characteristic impedance with this thing.

If you are interfacing to banana or any of those other connectors, then impedance is not important for the experiment.  Essentially by definition.

[Dave]

For a quick test, I'd simply use croc clips or J-hooks.
I don't mind spending 5 minutes to crimp a couple of custom cables together, if I'm going to be using them for a day or two. You'd have to waste a lot of connectors to outweigh the cost of such adapter.

Fair point on the BNC.

[001]

Awesome cute project 
I build similar from oil can years ago

[cgroen]

Brilliant idea 
(now is just the question, are you planning on making a small batch to sell, and if so, do you ship to Denmark  )

[dangrie]

Thank you very much for the constructive criticism and feedback.

I think that is rather neat and well done. You might swap places, with the BNC and Banana Socket sections. This would put the tallest component in the middle, giving better access to the lower Banana Socket components.

That totally makes sense! Thanks, I did not think if this. I just moved some stuff around and updated all files (See the github Link and also the updated images in my first Post.

Also, you may want to use the multi-connection type Banana Sockets. They provide more attachment options.

I don't quite understand what you mean by multi-connection type? Do you mean 2 Banaplugs in 1 Case with the standard spacing?

I am sure that you know that Banana sockets pair holes are set on 19mm centers.

Yes, the Banana Plugs are spaced 19mm apart in both directions.

If I need to connect something, I'd rather just crimp a couple of connectors onto a cable than have a bulky box sitting on my table. Most of the time you need more than 2 wires anyway.

Stopping a prototyping session because I have to "quickly" crimp a pair of cables was exactly what drove me into wanting something like this. Of course a crimped cable is always superior to having to dick around with adapters, but when I just need to temporarily power my project via jumper cables and only have a plug pack or benchtop supply I now don't have to look for contacts, housing, crimping tool, heat shrink etc. but can simply plug in my banana plugs into one end and attach the jumper cables on the other. I also do not waste a set of rather expensive banana connectors. Also I do have a much nicer way to connect my crocodile clips to any other cable. I find especially crocodile clips to be unreliable when simply connected to pin-headers or banana jacks or plugs.

Brilliant idea 
(now is just the question, are you planning on making a small batch to sell, and if so, do you ship to Denmark  )

Thanks! I did not currently plan to "manufacture" these in any way, but since I probably have some space PCBs and other parts and live in Germany, shipping should not be a problem. I plan to order the first batch of PCBs this weekend and can keep you updated. If you want, send me a PM and we'll figure something out

[cgroen]

PM sent Daniel

[gdewitte]

I recently built something similar (and also based on the Monsieur Adaptateur that I had purchased a few years ago and found very handy). I ditched the BNC figuring I could always use one of those BNC-to-banana plug adapters if needed, and added an Anderson Powerpole panel mount.

[t1d]

I don't quite understand what you mean by multi-connection type? Do you mean 2 Banaplugs in 1 Case with the standard spacing?

Look at the third/down picture of the "Multi-Connection Banana Socket," in my prior post. Look at the one with the nut raised. You will see that you can insert a wire, into the hole in the post, and tighten the nut, to secure the wire. With the grommet-style Banana Connector that you have specified, you do not have that additional option. Does that make sense?

If you make space for the multi-type, the grommet type will be accommodated, too, and the user can choose whichever they like.

Just a suggestion...

[t1d]

I have made a custom PCB library part, in Kicad, for the multi-type Banana Socket, if that is the CAD program that you are using... I think that I up-sized the hole, to accommodate the grommet-style type, too, but open the editor and double-check the hole diameter, just to make sure.

If you are using Eagle, there may be a converter out there, to adapt the file. I think that I have seen such a thing.

[t1d]

If using the multi-type, you will need to adjust the positive and negative orientation, of the individual component, to face the holes, to the side of the box.

For either style, you presently have...
+  +
-    -

This orientation would give more options...
+  -
-   +

By alternating the orientation, you add another direction to turn the Banana Plugs... Presently, they can only be oriented in perpendicular, to the box.  If you space all the holes at 19mm centers and modify the orientations, as I suggest, they could be plugged in perpendicular, or parallel, to the box.

[Conrad Hoffman]

It needs a couple male banana plugs sticking out the side so you can plug it into meters and such. You can also cheat and put an SO-239 female UHF connector on it, with a female banana jack 3/4" away. That gives you the 239 plus the ability to accept 3/4" dual banana plugs using the center of the 239.

[Gixy]

I have Something very similar. As I use it mainly for power supply connections, I have no BNC plug but USB female socket instead, and a LED to indicate power on.

[dangrie]

I don't quite understand what you mean by multi-connection type? Do you mean 2 Banaplugs in 1 Case with the standard spacing?

Look at the third/down picture of the "Multi-Connection Banana Socket," in my prior post. Look at the one with the nut raised. You will see that you can insert a wire, into the hole in the post, and tighten the nut, to secure the wire. With the grommet-style Banana Connector that you have specified, you do not have that additional option. Does that make sense?

If you make space for the multi-type, the grommet type will be accommodated, too, and the user can choose whichever they like.

Thanks. I will make sure to leave enough space so one can fit whichever socket they prefer
Do you have a link or Part# for the posts you used? they look awesome.

For either style, you presently have...
+  +
-    -

This orientation would give more options...
+  -
-   +

Thats a good point, going to update the board right now. Having more options is kind of the whole reason for the box.

I recently built something similar (and also based on the Monsieur Adaptateur that I had purchased a few years ago and found very handy). I ditched the BNC figuring I could always use one of those BNC-to-banana plug adapters if needed, and added an Anderson Powerpole panel mount.

Great, do you have som pictures? Do you know of any PCB-mount poles? However, I think I'm too limited in space with the form factor I'm targeting.

It needs a couple male banana plugs sticking out the side so you can plug it into meters and such. You can also cheat and put an SO-239 female UHF connector on it, with a female banana jack 3/4" away. That gives you the 239 plus the ability to accept 3/4" dual banana plugs using the center of the 239.

I thought about that but ditched the idea since this would mean I would always have sticking out poles connected to potentially high voltage and always risking shorting them. So I decided to just plug in a banana-cable to connect to meters and power supplies.

I have Something very similar. As I use it mainly for power supply connections, I have no BNC plug but USB female socket instead, and a LED to indicate power on.

USB may be a good option, I will check if I can fit it nicely. BNC is kind of important for me, since I have lots of BNC cables with different ends I can use for probing and now also powering, etc.

I also thought about the LED. How do you drive it with the varying input voltages? I thought about using an LM234 as a constant current source over a wide voltage range (certainly the 2-30V I use 99% of the time). It would also be protected up to 20V of reverse voltage which would help keep the circuit simple.

[t1d]

Do you have a link or Part# for the posts you used? they look awesome.

This is what I bought. They were the cheapest, at the time. But, I see some cheaper, today. So, shop around.

Also, there are a lot of different styles, of this same thing. I think I started with a search for "Speaker Banana Jacks." Adding "Speaker" seems to narrow the search, better.

https://www.ebay.com/itm/Banana-Plug-Terminal-Connector-Amplifier-Jack-Audio-Speaker-Adapter-Dual-Cable/282398851657?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

[gdewitte]

Here are two pictures of my home-built version: one 3/4 view showing the Powerpole panel mount end and the other 3/4 view showing the 5.5mm DC jack panel mount end. The box is a Hammond 1591 I had originally purchased for another project. I replaced its top cover with a piece of PC project board (ground plane on one side and solder pads on the other; I cut a length-wise break in the ground plane with my Dremel to make positive and negative sides). The Powerpoles use Anderson Autogrips from Hardened Power Systems (https://www.portableuniversalpower.com/our-products/anderson-autogrips/) for the panel mount.

[t1d]

I cut a length-wise break in the ground plane with my Dremel to make positive and negative sides).

Really nice job!

I take it that you just cut through the copper and not completely through the board. I think the line down the middle, that I am seeing, was made with a marker, as opposed to it being a cut's shadow... Correct?

[gdewitte]

Correct: only milled through the copper on the ground plane side; the line on the pad side was for reference.

[t1d]

Correct: only milled through the copper on the ground plane side; the line on the pad side was for reference.

I must laugh... I know myself... I would have way over-thought this... Designed a custom PCB, paid for it, waited for it, etc... When all I needed was a positive and negative plane.

Simply excellent, pun intended, on your part... A single piece of copper clad, divided, and a few holes...

Quirky, on mine. lol

[gdewitte]

[size=0px]I must laugh... I know myself... I would have way over-thought this... Designed a custom PCB, paid for it, waited for it, etc... When all I needed was a positive and negative plane.[/size]
[/size]
[/size][size=0px]I have to admit that a custom PCB was my first thought and I was considering a cutout for the Powerpoles, including a fuse holder for the positive plane, getting a right-angle PC mount 5.5 mm jack, silk screening spiffy labels, … And then I thought "Or, I could just mill the copper off the middle of a copper clad PCB and solder some parts on." [/size]

[gdewitte]

And, clearly, I need to work on the correct method for inserting a quote 

[Microcheap]

Neat  , I would just add maybe a micro USB connector for completeness

[Gixy]

I also thought about the LED. How do you drive it with the varying input voltages? I thought about using an LM234 as a constant current source over a wide voltage range (certainly the 2-30V I use 99% of the time). It would also be protected up to 20V of reverse voltage which would help keep the circuit simple.

Yes, simple current source (LM234 or opamp)