**PHR-803T**LPC-815**GBW-H10N**Sled/Diodes**

[Spyderz20x6]

[quote author=BluRay link=1226755361/80#92 date=1227345675]OK DrLava and SpyderX i added you to the list.


I will put the PAYPAL address back up when all this nonsense gets sorted out by them. As soon as its sorted, i will order  the GBW and LPC from GB#1 right away. SO if anyone else needs anything, please post it on here or in my pm.



Tommy

I would like to add one more GBW-H10 to my order please.  I will pay as soon as the address is back.

Just learned an important lesson about my cheapie DMM.  If I bump it during a current measurement, something inside opens the circuit and my LD becomes  an LED.  There goes my last 4x until this GB goes through.   :'( :'([/quote]
Thats what test loads are for :

 

[danq]

Just learned an important lesson about my cheapie DMM.  If I bump it during a current measurement, something inside opens the circuit and my LD becomes  an LED.  There goes my last 4x until this GB goes through.   :'( :'(

Thats what test loads are for :

Yes - and you can make your own current meter, it's easy and likely to be more accurate and reliable than a cheap DMM.

just get a decent digital panel voltmeter, then wire a 1-ohm resistor between the 2 leads. It's best if that R is close to the meter, but you won't suffer too much accuracy if it's not.  Be sure that all connections and test leads are low resistance.

The voltage displayed will be the current measured.  This may be more reliable than the dmm because there is no switch in the test path; and you have a low R so the measured circuit is not much disturbed (disturbance of the measured circuit is called "insertion loss").

If you want you can make it with a 0.1 ohm resistor for less insertion loss, but then you really need to be sure all connections (and test lead contacts) are low resistance (you can easily gold plate your test clips!). Of course, the actual current will then be 10 times the measured voltage.

DanQ

 

[IgorT]

SpydreXz, you can't measure the current through the diode on a test load. You can only measure current through the test load on a test load. He wasn't setting up the driver.

Dan.... Kage knows all that and more... Engineers can make silly mistakes too.. Usually the silliest..

 

[thebucketmouse]

[quote author=BluRay link=1226755361/80#92 date=1227345675]OK DrLava and SpyderX i added you to the list.


I will put the PAYPAL address back up when all this nonsense gets sorted out by them. As soon as its sorted, i will order  the GBW and LPC from GB#1 right away. SO if anyone else needs anything, please post it on here or in my pm.



Tommy

I would like to add one more GBW-H10 to my order please.  I will pay as soon as the address is back.

Just learned an important lesson about my cheapie DMM.  If I bump it during a current measurement, something inside opens the circuit and my LD becomes  an LED.  There goes my last 4x until this GB goes through.   :'( :'([/quote]


Wow, what a lame way to kill a diode. Sorry to hear that man

 

[danq]

SpydreXz, you can't measure the current through the diode on a test load. You can only measure current through the test load on a test load. He wasn't setting up the driver.

Dan.... Kage knows all that and more... Engineers can make silly mistakes too.. Usually the silliest..

well, if I'd known he was an engineer...
I would have given formal specifications!

 

[Kage]

[quote author=Kage link=1226755361/80#95 date=1227383702]Just learned an important lesson about my cheapie DMM. If I bump it during a current measurement, something inside opens the circuit and my LD becomes an LED. There goes my last 4x until this GB goes through. :'( :'(

Thats what test loads are for :

Yes - and you can make your own current meter, it's easy and likely to be more accurate and reliable than a cheap DMM.

just get a decent digital panel voltmeter, then wire a 1-ohm resistor between the 2 leads. It's best if that R is close to the meter, but you won't suffer too much accuracy if it's not. Be sure that all connections and test leads are low resistance.

The voltage displayed will be the current measured. This may be more reliable than the dmm because there is no switch in the test path; and you have a low R so the measured circuit is not much disturbed (disturbance of the measured circuit is called "insertion loss").

If you want you can make it with a 0.1 ohm resistor for less insertion loss, but then you really need to be sure all connections (and test lead contacts) are low resistance (you can easily gold plate your test clips!). Of course, the actual current will then be 10 times the measured voltage.

DanQ[/quote]

Yeah, I had just joked with Igor about being sure to use a test load. Then I do it to my best diode! Duh! :

I was comparing the output from a built-in .1 ohm sense resistor to the external current meter just to see if they were reasonably close. and they were within .7% no drift - so that was the good news.

 

[danq]

Yeah, I had just joked with Igor about being sure to use a test load.  Then I do it to my best diode!  Duh! :

I was comparing the output from a built-in .1 ohm sense resistor to the external current meter just to see if they were reasonably close. and they were within .7% no drift - so that was the good news.  

:-[ ;D just goes to illustrate how hard it is to know who I'm responding to - and at what level to respond. Ya never know if it's a genius or phd or 6th grader. I tend to err on the side of giving more information, and just hope a sophisticated correspondent isn't insulted.


DanQ

 

[Spyderz20x6]

SpydreXz, you can't measure the current through the diode on a test load. You can only measure current through the test load on a test load. He wasn't setting up the driver.

Dan.... Kage knows all that and more... Engineers can make silly mistakes too.. Usually the silliest..

Oh, i kinda rushed through his post.

 

[IgorT]

:-[ ;D just goes to illustrate how hard it is to know who I'm responding to - and at what level to respond. Ya never know if it's a genius or phd or 6th grader. I tend to err on the side of giving more information, and just hope a sophisticated correspondent isn't insulted.

 
DanQ

I know Dan, i know... I once explained to an engineer, how to solder.. ;D

 

[ElektroFreak]

Just learned an important lesson about my cheapie DMM.  If I bump it during a current measurement, something inside opens the circuit and my LD becomes  an LED.  There goes my last 4x until this GB goes through.   :'( :'(

I wanted to mention that if you are using an LM317 driver (and most other DIY drivers, I believe), you can read current from between the battery/power source and the driver instead of between the driver and LD. You'll get the same reading either way, give or take 0.1 mA or so.. a negligible enough amount of difference that it doesn't matter. You'll save a LOT of diodes that way...

 

[IgorT]

Kage is using his own switching drivers....

 

[phoenix3200]

Ya never know if it's a genius or phd or 6th grader.

Hmm...I guess a PhD does fit halfway in between being a genius and being a 6th grader

you can read current from between the battery/power source and the driver instead of between the driver and LD. You'll get the same reading either way

Unless you LD voltage is identical to your power source voltage and you have a 100% efficient driver, it doesn't work that way.  If those conditions are met, your driver is probably not any good.


w00t post #100!

 

[ElektroFreak]

I have only personally seen this work with lm317 drivers. All four of mine have been successfully driving diodes now for quite a while and I can measure the same current at the driver input as I can at the output, with a tiny margin of error. The drivers check out electrically and on the scope. All have rock-solid current regulation. The only diodes that have died running on these drivers were purposely overdriven.

I had another discussion about this here: http://www.laserpointerforums.com/forums/YaBB.pl?num=1227161304/0
and kind of described why this happens. Mostly it has to do with the fact that the lm317 deals with lack of efficiency by converting excess voltage/current into heat. This is also part of how it does its job of regulating. It draws very little current when used by itself with a bit of filter circuitry.

 

[phoenix3200]

Gotcha...I didn't pay attention to the LM317 note and thought you were making a generalization.

 

[IgorT]

Gotcha...I didn't pay attention to the LM317 note and thought you were making a generalization.

You had a switching driver in your head, cos you're working on one.. EFreak was talking linear..

 

[phoenix3200]

You had a switching driver in your head, cos you're working on one.. EFreak was talking linear..

I'll be building it too if the PCB company would hurry up. As my mom used to say, patience is not my middle name.

Getting on topic, BluRay, how long will it be until you order another set of PHR's?  I'd like to buy some more from you if it's before Jake gets back.