Rechargable Red OC Build w/HiPower Lens

[LarryDFW]

This is a photo of my new Red Open-Can Build:

LPC-815 diode running @ 350 ma. w/brass heatsink
#18650 Lithium-ion battery (2600mah)
Brass housing coated lens assembly (pretty good collimation)
Grey hard-anodized host; gold-plated tailcap spring
Still testing a few more lenses.

LarryDFW

 

[TheMonk]

Re: Rechargable Red Build

Nice build and nice size heatsink for OpenCan.

Are you using the AMC7135 driver for this.

 

[LarryDFW]

Re: Rechargable Red Build

No driver at all.

Just using a power resistor to drop the voltage to a set current of 350 ma (~3V).

Several hours of run time with the 2400 mah battery, before any significant voltage drop.

The AMC chip would work just fine.

LarryDFW

 

[Gazoo]

Re: Rechargable Red Build

Except the module has to be electrically isolated if using the 7135...

 

[Nameless_Ranger]

Re: Rechargable Red Build

What value is the resistor for that much current? (ohms/wattage)

 

[LarryDFW]

Re: Rechargable Red Build

What value is the resistor for that much current? (ohms/wattage)

I used 3.9 ohms @ 1/2 watt.

It's only dropping ~ 1.2 volts

LarryDFW

 

[Mexawy]

Re: Rechargable Red OC Build

is the laser dead because there is no driver ? or still alive ?
and can you tell me which host it this ?
thanks

 

[LarryDFW]

Re: Rechargable Red OC Build

The OC Red is still working very well (11 months w/~ an hour per month).

The resistor is more reliable than any electronic driver.

It now has a newer lens AR-coated for Red LD's.

Here's a photo with reflection from the rain at the recent Candlepower Forum meeting in Arlington:

I picked the host because it was hard-anodized ...
and uses a #18650 li-ion battery:

Host Link

LarryDFW