Power Meter Calibration and Comparison

[danq]

Here's a mockup of what I was thinking:

rkcstr that looks very good to me - exception being that Kenom's spec should be used for the connector to the Dorcys, because he knows what fits.

But... are there 2 connectors here? one at each end of a 2-wire cable? that's what it sounds like if there's a connector on the box. That means a loose cable to ship around or get lost (I've seen those photos of Ken's workspace, and mine is sometimes similar)  :

Suggestion: no connector on the box - just cable out, terminated with whatever Kenom wants to plug into his end. I mean plug into the Dorcys. ;-)

Hey, what about just using a standard audio cable - with, say, an RCA jack?


Alternatively, rkcstr could make a cable that plugs into whatever he feels like on his end, leaving the other end unterminated; then Kenom can add whatever he wants on the other end! Still leaves us with a loose and non-standard cable though... I like the standard audio cable better.

DanQ

 

[IgorT]

Looking good!


Audio cables are good, but audio plugs are not..

I use them on some of the devices i make at work, and they can be very tricky. I actually have to buy the plug in one shop and a socket in another, for them to work perfectly with each other. Otherwise, you just look at it funny and it interrupts.. Something, that is not noticable in audio but can be bad in a more sensitive application.

Pretty much any other socket/plug combo is better than audio plugs.

 

[rkcstr]

The idea was that the socket would be on the PSU and then a wire coming out of the laser housing with a plug on the end of it to connect to the PSU... there would be no plug on the laser housing end, just a wire coming out of it, unless you'd prefer a socket on both ends?

Oh, and I think the socket is smaller than it appears, it's tough to resize things to scale in Photoshop :-/ The widest part is 17mm in diameter, the inner part is 13.5mm.

This is what I had in mind:

EDIT: Igor, you may be right... I was just trying to find a plug-in connector that was relatively cheap. I'll look around to see if I can find something better. BTW, it's not actually marketed as an "audio" connector, it looks similar (to me) to a PS2 mouse port. the left hand panel on this catalog page, 3-pin mini-DIN:
http://www.mouser.com/catalog/635/1272.pdf

 

[rkcstr]

Oh, and here's the mini-DIN connector shown to more accurate proportions:

And, also more accurate: ;D

 

[danq]

yeah, that would be better than audio...
anyway, what rkcstr's proposed/illustrated comes out the same to me - he can do that connector;ship it all out to Kenom; Kenom can either hardwire or put a connector on his end.

 

[IgorT]

BTW, it's not actually marketed as an "audio" connector, it looks similar (to me) to a PS2 mouse port. the left hand panel on this catalog page, 3-pin mini-DIN:

This plug should be good.. I was talking about the 3.5mm stereo jack. Like the ones found on headphones.. Those can be very flimsy..

EDIT: I was answering to DanQ, because i wasn't sure what an RCA jack is.. The socket in your pictures has a much firmer grip on the pins..

 

[Kenom]

Actually I really like rckstrs idea of having the wire terminate inside the barrel.  I can then just glue the wire in.  Of course tie the old' electricians knot on the inside so it doesn't come loose.  Very good idea indeed.  Then it just plugs into the psu.  one or the other.  I do NOT want to see the ability to plug both in simultaneously as I see no benefit or need for that at all.  Dooo eet.

Do you need me to ship you my IEC or UEC or whatever it's called?

 

[rkcstr]

Also, I found these DC connectors which should have secure contact as well as being twist-lock so they shouldn't pull out accidentally and they're actually cheaper than the others... so I may use them instead.  Whaddaya think?

Plug:
http://www.mouser.com/Search/ProductDetail.aspx?qs=xQLC6%2biNr%2b5MWDRjhaS8ww==

Jack:
http://www.mouser.com/Search/ProductDetail.aspx?R=163-1100-EXvirtualkey11180000virtualkey163-1100-EX

You can see what they actually look like here (the 1/4 turn locking, not screw on):
http://www.minute-man.com/acatalog/Online_Catalog_Locking_Coaxial_Power_Plugs___Jacks_202.html

Do you need me to ship you my IEC or UEC or whatever it's called?

Nah... that's okay, they're only about $1 each, I was actually going to buy a few extra for myself  ;D

 

[IgorT]

Also, I found these DC connectors which should have secure contact as well as being twist-lock so they shouldn't pull out accidentally and they're actually cheaper than the others... so I may use them instead.  Whaddaya think?

These should be good.. I use these all the time in my devices. The only plugs/sockets i ever had problems with are the headphone jacks. Unfortunatelly i often need three connections and a small socket/plug..

If at all possible, i use the DC adapter connectors or the DIN / Mini DIN connectors instead. Never had any problems with them in 10 years.. The headphone sockets need to be replaced all the time on the other hand..


Oh, and strain reliefs, where cables leave a box or laser would be very good.. You can make a simple one from overlapping shrink tubing. Whenever i have to repair one of my devices, it's always a broken cable at the spot where it leaves an enclosure, because people like wrapping cables tightly, and make a 90° bend in it at the point where it comes out.


But if the back of the laser will be filled with silicone, it will be soft.


Kenom: You are right.. One plug is always better than two.

 

[Zom-B]

I was thinking too about having the wire terminate in the laser, but then I thought, it would require to ship more wire than necessary. If the wire terminated in the box then there's less wire. Downside is that a plug has to be firmly attached in the Dorcy, so I think the dorcy-with-wire is the better option after all. Weight difference is also negligible.

Is the back cap of the Dorcy's made of such a material that drilling a hole in it is feasible? In that case, only the electrician's knot and anti-tamper glue (red/blue Locktite or for example) are necessary. (so you can see if it has been tampered with)

 

[rkcstr]

Both of the connector types appear to have a built-in strain relief, so that shouldn't be a problem.  I'm leaning toward the DC connector because it will lock in place so that it won't accidently disconnect, though I think the mini-DIN probably won't just pull out very easily either.  Anyone have a preference?

Also, not sure if you have an idea on what cable you want to use Kenom, but I have some of this gray 3 conductor wire meant for audio cable below.  It's 22ga wire and shielded, though that's not really an issue here.  The only downside is that it is not greatly flexible, but it would work.  If you have access to a nice super flexible cable, I can just leave mine off.  Also, just need to decide what length to make the wire as well if I am supplying it.

Actually, scratch that, I just found an old broken laptop charger that had a nice flexible cable on it and looks to be 2 conductor 18ga wire, only 3.2mm diameter and I have about 4ft of it... should work nicely ;D

laptop wire

shielded audio wire

 

[danq]

ok - everything's decided
now it's time to make like a small burrowing rodent:

GOPHER   IT!

 

 

[rkcstr]

Ordering parts tonight, USPS Priority... should be here by Thu.  

I'm sending this to you, Kenom, right?  If I have enough time, I may have it ready in time to ship that day or Friday.

 

[Kenom]

yeah.  ship it to me.  The only thing I need from you is an estimate of costs for your portion of the build.  That way I can put up the price break down for the number of participants and have folks start payin.  What you have proposed there works for me.  As long as the parts needed to add the cable/ and plug and the psu is all I would need.  that and 2 adjustable drivers.  Thanks.

Concerning the back of the laser. I will not be putting the tailcap on. it's a waste of time trying to modify the endcap to work with what we need. Just fill the end with silicone and seal it up so that it can't be messed with once it's set. Plus it's much quicker.

 

[rkcstr]

Yeah, I was going to make up the PSU, attach wire to each of the plugs for the laser, and do you want me to attach the drivers to the other end of the wire? Also, for the drivers, if we're doing a red and a violet, I can do a high (120-430) and a low (30-150) to making it easier to finely adjust the current, I'll just mark them as such, okay? And, if I'm attaching the drivers, how long would you like the wire?

And, FINALLY, I'm going to ship in a small cardboard box with foam inserts. If you want, you can give me the dimensions of the two laser housing (and tripod?) and I'll find a way to fit it all in there so things fit snugly and simplify shipping of everything.

 

[Kenom]

Well, lets work in reverse chronilogical order. 1. I have boxes galore I've purchased for shipping the Kryton laser barrels. one of those boxes is the one that i use for shipping orders up to 8 barrels, is small enough to fit the barrels in and big enough (barely) for the customs forms if needed. I was then going to cut out egg crate foam (of which I have a ton) and make some small pockets for everything to fit into nice and neat. So I don't think you need to go all out to ship it to me, although I do appreciate the extra effort and thought. However if you are really intent on providing the box. I will not stop you. The dorcy's are 83mm long and 28mm at it's widest. tripod is 6 inches long and 1/2" x 1 1/2". The Dx clip that goes on top is 2"x2"x3"

2. Wire length. I'm going to go out on a limb here and say a length. This length is going to be with the wire from the plug going into the wall taken into consideration as generally those are six feet and we don't really need that much distance between the laser and the psu, only enough to make sure the heat from us is not a factor in the meters reading. so with that said, the number I'm going to say is 2' it's small enough it can be wound into a small circle and big enough to give us a bit of distance between the meter and the laser.

3. The ranges you selected sound good to me.

4. You can solder the driver to the wire. that really doesn't make any difference. Make one less step for me trying to figure which wire is neg and Pos. (not that this is hard.)