Laser pointer discussion. Read/write reviews of laser pointers and laser pointer companies. Learn about all types of laser pointers and lasers





Welcome to Laser Pointer Forums! If you are looking for a laser pointer or want to compare different laser pointer companies, you may want to check out the LPF Laser Pointer Company Database.




Green Laser Pointers by Category Blue Laser Pointers by Category Red Laser Pointers by Category
Yellow Laser Pointers by Category Violet Laser Pointers by Category Orange Laser Pointers by Category
Top Laser Pointers by Power - 1 Watt+ Top Laser Pointers by Power - 500mW+ Top Laser Pointers by Power - 250mW+
Laser Pointer Database High Power Laser Pointers Laser Pointer Diodes
Laser Technology Laser Pointer Parts Lasers by Wavelength
Top 10 Laser Pointer Companies Laser Pointer Company Database Visible Beam Laser Pointers


One laser store meets all your needs

























Go Back   Laser Pointer Forums - Discuss Laser Pointers > Lasers > General

LPF List of Laser Pointer Companies (link opens new window)



Reply
 
LinkBack Thread Tools Display Modes
Old 06-09-2017, 01:13 AM #33
Benm's Avatar
Class 4 Laser
 
Join Date: Aug 2007
Location: Netherlands
Posts: 7,242
Rep Power: 7527
Benm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond repute
Benm Benm is online now
Class 4 Laser
Benm's Avatar
 
Join Date: Aug 2007
Location: Netherlands
Posts: 7,242
Rep Power: 7527
Benm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond repute
Default Re: Dead M140?

Well, if you are building the dummy load from scratch i'd go for 1n 540x diodes as they can handle 3 amps and are still very cheap.

Some designs have been proposed with more powerful diodes as well, but they require to be mounted to a heatsink - not really a problem, but if you plan on staying at the 'around 1 amp' range probably overkill.

There is also the resistor. If you want it at 1 ohm, you could just put 10 standard metal film 10 ohm resistors in paralel. This would be fine up to 2 amps continous operation. You could also use 20 pcs of 20 ohm resistors in there, making it reliable up to (almost) 3 amps, same limit as the diode.

Actually putting a load of resistors in paralel has advantages: they are often cheaper than high power resistors even if you need 10 or 20 of them, and they have low inductance. Cheap power resistors are often wire-wound which work fine for DC, but present a pretty inductive load to the driver under test.

There are low-inductance high-power resistors too, with heatsink mounting, but those only make sense when you want a dummy load that handles currents of 5 amps or so, where the diodes would also require external heatsinking.


Benm is online now   Reply With Quote







LPF List of Laser Pointer Companies (link opens new window)






Old 06-09-2017, 02:39 AM #34
paul1598419's Avatar
Class 3B Laser
 
Join Date: Sep 2013
Location: Washington State
Posts: 4,107
Rep Power: 19040
paul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond repute
paul1598419 paul1598419 is online now
Class 3B Laser
paul1598419's Avatar
 
Join Date: Sep 2013
Location: Washington State
Posts: 4,107
Rep Power: 19040
paul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond repute
Default Re: Dead M140?

Last time I bought rectifiers, I got 50, 10 amp 1000 VPRV for under $3.00. I also got my resistors in 1% tolerance at equally cheap prices. They aren't wire wound. I can only imagine the cluster f@#k look of 20, 20 ohm resistors soldered together in parallel. I suppose it would dissipate heat better, but seems like overkill.
__________________
405nm Laser Pointer 45mW
405nm C11 700mW
405nm Laser Shack Pointer 80mW
Thor H Dual Power 445nm, 438 mW & 1648 mW
445nm 1.75 watts SkyRay Gifted
445nm 3 watts MS-SSW-II
445nm 2.2 watts Nichia MS Envy

445nm 2 watt SMP Copper Host
488nm Uniphase #2201-20SLAT argon laser head and power supply >40mW
LSR532H-1W Laser, LSR-PS-N1 Driver, RS-75-5 P.S. 1300 mW
532nm 200mW thermostatically Fan Cooled (Besram) >230mW
532nm 189mW pocket lab laser
532nm lasers X6 100mW-200mW
532nm lasers X4 75mW- 140mW
632.8nm P210 New Laser Tube 0.57mW Melles Griot 05-LMP-827-037 PSU New
632.8nm Spectra- Physics He- Ne #102-2 4mW heads X2 and #236 power supply
632.8nm PMS He-Ne # 201P/ LPS-115 2mW
632.8nm Siemens HeNe LGK7630S 7.6mW
635nm 1 watt Cyprus II
635nm 1 watt SMP Copper host
635nm 5mW pointer
635nm 100mW pointer
635nm Lifetime17 Mini-camo build 687mW
650nm 65mW pointer
650nm 380mW 501B
808nm 1+W infrared laser
infrared video camera for collimating IR lasers
Ocean Optics USB2000 Spectrometer
Scientech Vector S310 with AC2500 10 Watt LPM
LaserBee II 3.2 Watt LPM
Radiant X4 3.7 Watt LPM
Eisco Scientific Spectroscope 400nm- 700nm
paul1598419 is online now   Reply With Quote
Old 06-09-2017, 04:39 AM #35
WizardG's Avatar
Class 2 Laser
 
Join Date: May 2011
Location: Oregon
Posts: 397
Rep Power: 2484
WizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond repute
WizardG WizardG is online now
Class 2 Laser
WizardG's Avatar
 
Join Date: May 2011
Location: Oregon
Posts: 397
Rep Power: 2484
WizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond reputeWizardG has a reputation beyond repute
Default Re: Dead M140?

" I can only imagine the cluster f@#k look of 20, 20 ohm resistors soldered together in parallel."


Well, that would depend on the skill of the one soldering them together.
__________________
125mW 405
1.157 watt 447
2 meter long hene @ 57mW
Assorted greenies, best @ 244mW of 520
WizardG is online now   Reply With Quote
Old 06-09-2017, 10:06 PM #36
IVO IVO is offline
Junior Member
 
Join Date: Jun 2017
Location: Spain
Posts: 13
Rep Power: 0
IVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond repute
IVO IVO is offline
Junior Member
 
Join Date: Jun 2017
Location: Spain
Posts: 13
Rep Power: 0
IVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond repute
Default Re: Dead M140?

Hi!

There it is...
Dead M140?-dummy-load.jpg

Dead M140?-dummy-load-test.jpg

And it was set to 280mA. Measuring in series with the multimer it reads 279mA. I think It's within the margin of error.
The resistors are x10 10R 1W resistors, so the should hold up well at the max 3A that the diodes can resist.

Last edited by IVO; 06-09-2017 at 10:11 PM.
IVO is offline   Reply With Quote
Old 06-09-2017, 11:18 PM #37
paul1598419's Avatar
Class 3B Laser
 
Join Date: Sep 2013
Location: Washington State
Posts: 4,107
Rep Power: 19040
paul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond repute
paul1598419 paul1598419 is online now
Class 3B Laser
paul1598419's Avatar
 
Join Date: Sep 2013
Location: Washington State
Posts: 4,107
Rep Power: 19040
paul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond repute
Default Re: Dead M140?

Looks good. If you have a meter that can read low resistance, it wouldn't hurt to confirm your 10, 10 ohm resistors in parallel are in fact 1 ohm. You will want to limit the time you use this dummy load for drivers above 1.5 amps as the rectifiers will overheat. Otherwise, it should work well for drivers up to 2.5 amps. Maybe a little more.
__________________
405nm Laser Pointer 45mW
405nm C11 700mW
405nm Laser Shack Pointer 80mW
Thor H Dual Power 445nm, 438 mW & 1648 mW
445nm 1.75 watts SkyRay Gifted
445nm 3 watts MS-SSW-II
445nm 2.2 watts Nichia MS Envy

445nm 2 watt SMP Copper Host
488nm Uniphase #2201-20SLAT argon laser head and power supply >40mW
LSR532H-1W Laser, LSR-PS-N1 Driver, RS-75-5 P.S. 1300 mW
532nm 200mW thermostatically Fan Cooled (Besram) >230mW
532nm 189mW pocket lab laser
532nm lasers X6 100mW-200mW
532nm lasers X4 75mW- 140mW
632.8nm P210 New Laser Tube 0.57mW Melles Griot 05-LMP-827-037 PSU New
632.8nm Spectra- Physics He- Ne #102-2 4mW heads X2 and #236 power supply
632.8nm PMS He-Ne # 201P/ LPS-115 2mW
632.8nm Siemens HeNe LGK7630S 7.6mW
635nm 1 watt Cyprus II
635nm 1 watt SMP Copper host
635nm 5mW pointer
635nm 100mW pointer
635nm Lifetime17 Mini-camo build 687mW
650nm 65mW pointer
650nm 380mW 501B
808nm 1+W infrared laser
infrared video camera for collimating IR lasers
Ocean Optics USB2000 Spectrometer
Scientech Vector S310 with AC2500 10 Watt LPM
LaserBee II 3.2 Watt LPM
Radiant X4 3.7 Watt LPM
Eisco Scientific Spectroscope 400nm- 700nm
paul1598419 is online now   Reply With Quote
Old 06-09-2017, 11:36 PM #38
IVO IVO is offline
Junior Member
 
Join Date: Jun 2017
Location: Spain
Posts: 13
Rep Power: 0
IVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond repute
IVO IVO is offline
Junior Member
 
Join Date: Jun 2017
Location: Spain
Posts: 13
Rep Power: 0
IVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond repute
Default Re: Dead M140?

Quote:
Originally Posted by paul1598419 View Post
Looks good. If you have a meter that can read low resistance, it wouldn't hurt to confirm your 10, 10 ohm resistors in parallel are in fact 1 ohm. You will want to limit the time you use this dummy load for drivers above 1.5 amps as the rectifiers will overheat. Otherwise, it should work well for drivers up to 2.5 amps. Maybe a little more.
My multimeter shows 0.9ohm, but i don't know how good it is for measuring low resistance.
IVO is offline   Reply With Quote
Old 06-09-2017, 11:47 PM #39
paul1598419's Avatar
Class 3B Laser
 
Join Date: Sep 2013
Location: Washington State
Posts: 4,107
Rep Power: 19040
paul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond repute
paul1598419 paul1598419 is online now
Class 3B Laser
paul1598419's Avatar
 
Join Date: Sep 2013
Location: Washington State
Posts: 4,107
Rep Power: 19040
paul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond repute
Default Re: Dead M140?

Quote:
Originally Posted by IVO View Post
My multimeter shows 0.9ohm, but i don't know how good it is for measuring low resistance.

What does it read when you short the leads? If it is above 0.0 ohms you might have a problem. I have an ESR meter for capacitors that can measure down to mohms. Maybe you do too?
__________________
405nm Laser Pointer 45mW
405nm C11 700mW
405nm Laser Shack Pointer 80mW
Thor H Dual Power 445nm, 438 mW & 1648 mW
445nm 1.75 watts SkyRay Gifted
445nm 3 watts MS-SSW-II
445nm 2.2 watts Nichia MS Envy

445nm 2 watt SMP Copper Host
488nm Uniphase #2201-20SLAT argon laser head and power supply >40mW
LSR532H-1W Laser, LSR-PS-N1 Driver, RS-75-5 P.S. 1300 mW
532nm 200mW thermostatically Fan Cooled (Besram) >230mW
532nm 189mW pocket lab laser
532nm lasers X6 100mW-200mW
532nm lasers X4 75mW- 140mW
632.8nm P210 New Laser Tube 0.57mW Melles Griot 05-LMP-827-037 PSU New
632.8nm Spectra- Physics He- Ne #102-2 4mW heads X2 and #236 power supply
632.8nm PMS He-Ne # 201P/ LPS-115 2mW
632.8nm Siemens HeNe LGK7630S 7.6mW
635nm 1 watt Cyprus II
635nm 1 watt SMP Copper host
635nm 5mW pointer
635nm 100mW pointer
635nm Lifetime17 Mini-camo build 687mW
650nm 65mW pointer
650nm 380mW 501B
808nm 1+W infrared laser
infrared video camera for collimating IR lasers
Ocean Optics USB2000 Spectrometer
Scientech Vector S310 with AC2500 10 Watt LPM
LaserBee II 3.2 Watt LPM
Radiant X4 3.7 Watt LPM
Eisco Scientific Spectroscope 400nm- 700nm

Last edited by paul1598419; 06-09-2017 at 11:49 PM.
paul1598419 is online now   Reply With Quote
Old 06-09-2017, 11:54 PM #40
IVO IVO is offline
Junior Member
 
Join Date: Jun 2017
Location: Spain
Posts: 13
Rep Power: 0
IVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond repute
IVO IVO is offline
Junior Member
 
Join Date: Jun 2017
Location: Spain
Posts: 13
Rep Power: 0
IVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond repute
Default Re: Dead M140?

When I short the leads of the multimeter It reads 0.0 Ohms.
I don't have an ESR meter.

Last edited by IVO; 06-09-2017 at 11:55 PM.
IVO is offline   Reply With Quote
Old 06-09-2017, 11:56 PM #41
paul1598419's Avatar
Class 3B Laser
 
Join Date: Sep 2013
Location: Washington State
Posts: 4,107
Rep Power: 19040
paul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond repute
paul1598419 paul1598419 is online now
Class 3B Laser
paul1598419's Avatar
 
Join Date: Sep 2013
Location: Washington State
Posts: 4,107
Rep Power: 19040
paul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond repute
Default Re: Dead M140?

Hard to say. Do you have any 1 ohm resistors to measure to see what they read? Or even a 2.2 ohm. Something else to test against?
__________________
405nm Laser Pointer 45mW
405nm C11 700mW
405nm Laser Shack Pointer 80mW
Thor H Dual Power 445nm, 438 mW & 1648 mW
445nm 1.75 watts SkyRay Gifted
445nm 3 watts MS-SSW-II
445nm 2.2 watts Nichia MS Envy

445nm 2 watt SMP Copper Host
488nm Uniphase #2201-20SLAT argon laser head and power supply >40mW
LSR532H-1W Laser, LSR-PS-N1 Driver, RS-75-5 P.S. 1300 mW
532nm 200mW thermostatically Fan Cooled (Besram) >230mW
532nm 189mW pocket lab laser
532nm lasers X6 100mW-200mW
532nm lasers X4 75mW- 140mW
632.8nm P210 New Laser Tube 0.57mW Melles Griot 05-LMP-827-037 PSU New
632.8nm Spectra- Physics He- Ne #102-2 4mW heads X2 and #236 power supply
632.8nm PMS He-Ne # 201P/ LPS-115 2mW
632.8nm Siemens HeNe LGK7630S 7.6mW
635nm 1 watt Cyprus II
635nm 1 watt SMP Copper host
635nm 5mW pointer
635nm 100mW pointer
635nm Lifetime17 Mini-camo build 687mW
650nm 65mW pointer
650nm 380mW 501B
808nm 1+W infrared laser
infrared video camera for collimating IR lasers
Ocean Optics USB2000 Spectrometer
Scientech Vector S310 with AC2500 10 Watt LPM
LaserBee II 3.2 Watt LPM
Radiant X4 3.7 Watt LPM
Eisco Scientific Spectroscope 400nm- 700nm
paul1598419 is online now   Reply With Quote
Old 06-09-2017, 11:58 PM #42
IVO IVO is offline
Junior Member
 
Join Date: Jun 2017
Location: Spain
Posts: 13
Rep Power: 0
IVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond repute
IVO IVO is offline
Junior Member
 
Join Date: Jun 2017
Location: Spain
Posts: 13
Rep Power: 0
IVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond repute
Default Re: Dead M140?

I have 1.8 Ohm resistors. Ok, it now reads 1.0 Ohm, but it sometimes goes up to 1.1, or down to 0.9. I think it's just not soo good for low seristances.

Last edited by IVO; 06-10-2017 at 12:06 AM.
IVO is offline   Reply With Quote
Old 06-10-2017, 12:12 AM #43
paul1598419's Avatar
Class 3B Laser
 
Join Date: Sep 2013
Location: Washington State
Posts: 4,107
Rep Power: 19040
paul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond repute
paul1598419 paul1598419 is online now
Class 3B Laser
paul1598419's Avatar
 
Join Date: Sep 2013
Location: Washington State
Posts: 4,107
Rep Power: 19040
paul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond repute
Default Re: Dead M140?

You can only go by what you have to work with. I'd check some 1.8 ohm resistors just to see.
__________________
405nm Laser Pointer 45mW
405nm C11 700mW
405nm Laser Shack Pointer 80mW
Thor H Dual Power 445nm, 438 mW & 1648 mW
445nm 1.75 watts SkyRay Gifted
445nm 3 watts MS-SSW-II
445nm 2.2 watts Nichia MS Envy

445nm 2 watt SMP Copper Host
488nm Uniphase #2201-20SLAT argon laser head and power supply >40mW
LSR532H-1W Laser, LSR-PS-N1 Driver, RS-75-5 P.S. 1300 mW
532nm 200mW thermostatically Fan Cooled (Besram) >230mW
532nm 189mW pocket lab laser
532nm lasers X6 100mW-200mW
532nm lasers X4 75mW- 140mW
632.8nm P210 New Laser Tube 0.57mW Melles Griot 05-LMP-827-037 PSU New
632.8nm Spectra- Physics He- Ne #102-2 4mW heads X2 and #236 power supply
632.8nm PMS He-Ne # 201P/ LPS-115 2mW
632.8nm Siemens HeNe LGK7630S 7.6mW
635nm 1 watt Cyprus II
635nm 1 watt SMP Copper host
635nm 5mW pointer
635nm 100mW pointer
635nm Lifetime17 Mini-camo build 687mW
650nm 65mW pointer
650nm 380mW 501B
808nm 1+W infrared laser
infrared video camera for collimating IR lasers
Ocean Optics USB2000 Spectrometer
Scientech Vector S310 with AC2500 10 Watt LPM
LaserBee II 3.2 Watt LPM
Radiant X4 3.7 Watt LPM
Eisco Scientific Spectroscope 400nm- 700nm
paul1598419 is online now   Reply With Quote
Old 06-10-2017, 12:24 AM #44
IVO IVO is offline
Junior Member
 
Join Date: Jun 2017
Location: Spain
Posts: 13
Rep Power: 0
IVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond repute
IVO IVO is offline
Junior Member
 
Join Date: Jun 2017
Location: Spain
Posts: 13
Rep Power: 0
IVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond reputeIVO has a reputation beyond repute
Default Re: Dead M140?

It sometimes reads 1.8, but sometimes lower, like 1.6. I've never calibrated my multimeter, so it might be reading lower than It should.
IVO is offline   Reply With Quote
Old 06-10-2017, 12:28 AM #45
Benm's Avatar
Class 4 Laser
 
Join Date: Aug 2007
Location: Netherlands
Posts: 7,242
Rep Power: 7527
Benm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond repute
Benm Benm is online now
Class 4 Laser
Benm's Avatar
 
Join Date: Aug 2007
Location: Netherlands
Posts: 7,242
Rep Power: 7527
Benm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond reputeBenm has a reputation beyond repute
Default Re: Dead M140?

Soldering many resistors in paralel is not that uncommon really, it was a pretty common practice to create low-inductance dummy loads to test radio transmitters in (20 1k resistors make a neat little 50 ohm dummy load, soldering right onto the connector working fine up to 100s of MHz at least).

To measure the resistance: using your multimeter directly is not realiable due to resistance in the leads and all that. If you have a constant current lab supply, just set that to 1 amp and measure the voltage. Or measure the current using the multimeters 20A range and then the voltage across.

Essentially you're doing a four point measurement without the specific meter to do that - if you have one of those you'll not need to read this
Benm is online now   Reply With Quote
Old 06-10-2017, 03:53 AM #46
paul1598419's Avatar
Class 3B Laser
 
Join Date: Sep 2013
Location: Washington State
Posts: 4,107
Rep Power: 19040
paul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond repute
paul1598419 paul1598419 is online now
Class 3B Laser
paul1598419's Avatar
 
Join Date: Sep 2013
Location: Washington State
Posts: 4,107
Rep Power: 19040
paul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond reputepaul1598419 has a reputation beyond repute
Default Re: Dead M140?

Quote:
Originally Posted by IVO View Post
It sometimes reads 1.8, but sometimes lower, like 1.6. I've never calibrated my multimeter, so it might be reading lower than It should.
It's hard to say for sure, but it could be that you aren't making a good connection every time you are measuring resistance. The leads shouldn't make that much difference as they should be stranded wire in a fairly heavy gauge. But, the connect you make with the probes can make a difference in small resistances. The quality of the meter will make a difference as well. You can use a constant current, constant voltage power supply to test the dummy load by setting it for 1 amp and figure the amount of voltage drop across your diodes and resistor. Set the output voltage for the amount you calculated. Then measure the drop across the paralleled resistors to see if you get 1000 mV.
__________________
405nm Laser Pointer 45mW
405nm C11 700mW
405nm Laser Shack Pointer 80mW
Thor H Dual Power 445nm, 438 mW & 1648 mW
445nm 1.75 watts SkyRay Gifted
445nm 3 watts MS-SSW-II
445nm 2.2 watts Nichia MS Envy

445nm 2 watt SMP Copper Host
488nm Uniphase #2201-20SLAT argon laser head and power supply >40mW
LSR532H-1W Laser, LSR-PS-N1 Driver, RS-75-5 P.S. 1300 mW
532nm 200mW thermostatically Fan Cooled (Besram) >230mW
532nm 189mW pocket lab laser
532nm lasers X6 100mW-200mW
532nm lasers X4 75mW- 140mW
632.8nm P210 New Laser Tube 0.57mW Melles Griot 05-LMP-827-037 PSU New
632.8nm Spectra- Physics He- Ne #102-2 4mW heads X2 and #236 power supply
632.8nm PMS He-Ne # 201P/ LPS-115 2mW
632.8nm Siemens HeNe LGK7630S 7.6mW
635nm 1 watt Cyprus II
635nm 1 watt SMP Copper host
635nm 5mW pointer
635nm 100mW pointer
635nm Lifetime17 Mini-camo build 687mW
650nm 65mW pointer
650nm 380mW 501B
808nm 1+W infrared laser
infrared video camera for collimating IR lasers
Ocean Optics USB2000 Spectrometer
Scientech Vector S310 with AC2500 10 Watt LPM
LaserBee II 3.2 Watt LPM
Radiant X4 3.7 Watt LPM
Eisco Scientific Spectroscope 400nm- 700nm
paul1598419 is online now   Reply With Quote
Reply





Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On











Loading








Green Laser Pointers by Category Blue Laser Pointers by Category Red Laser Pointers by Category
Yellow Laser Pointers by Category Violet Laser Pointers by Category Orange Laser Pointers by Category
Top Laser Pointers by Power - 1 Watt+ Top Laser Pointers by Power - 500mW+ Top Laser Pointers by Power - 250mW+
Laser Pointer Database High Power Laser Pointers Laser Pointer Diodes






Privacy Policy | Advertising Disclaimer | Terms of Use


 


All times are GMT. The time now is 02:03 PM.


Powered by: vBulletin
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO
Privacy Policy | Advertising Disclaimer | Terms of Use
Copyright (C) 2017 Laser Pointer Forums, LLC