Reflektor-D builds

[merlin el mago]

Thank you. Yes Mike sent me 2 green + 2 reds + 2 yellows. How much voltage is the diode?

 

[Salas]

At that low current maybe 0.5-0.6V but depends on sample. Use the Atlas.

 

[merlin el mago]

Diode 0.68V
Red LED 1.78V
Red LED 1.76V
Residual 1.22V

Total 5.44V

Green & yellow LEDs have more voltage.

 

[Salas]

Diode test at how many mA?

 

[Salas]

Try on the reg, it will run a lower total.

 

[merlin el mago]

Diode test at how many mA?

I don't know, measured with the Atlas.

 

[merlin el mago]

Try on the reg, it will run a lower total.

OK I will try.

Diode 0.68V
Red LED 1.78V
Red LED 1.76V
Residual 1.22V

Total 5.44V

 

[Salas]

The model 55? It scrolls and mentions current if I remember correctly. Maybe 5mA.

At 2mA those reds were 1.735V. You got to test with dummy on the reg, wait to go hot and measure. Just solder lightly on top edge of the pad before finalizing choices. You don't have to use diode only, you can use resistor also. 0.02V for 10 Ohm, 0.2V for 100 Ohm etc.

 

[merlin el mago]

Yes is the Atlas DCA55, one LED 3.54mA the other 3.52mA

 

[Salas]

Still more than in the reg. Look in the instructions there is a diagram with a resistor and a 9V battery for 2mA. Maybe two greens and a small resistor instead of diode will be the easiest in the end. Has to be 5.25V exactly, or there is allowance?

 

[merlin el mago]

9V battery & 3K3? I don't know if needs exactly 5.25V but is the only value write in the manual pdf.

 

[Salas]

Yes. And 10 Ohm 10W dummy in your case.

 

[merlin el mago]

With battery one red LED 1.723V the other red LED 1.720V

 

[merlin el mago]

With battery one green LED 1.904V the other green LED 1.903V

If calculations are OK: 2 green LEDs + 100 Ohms, OK?

 

[merlin el mago]

Can I use the two DALE CPF3 2R and 1R5 in parallel 0R85 for R1 to set aprox. 0.73A with 0.82R R1?

 

[Salas]

With battery one green LED 1.904V the other green LED 1.903V

If calculations are OK: 2 green LEDs + 100 Ohms, OK?

Seems OK. Although it will go a bit down when hot depending on how hot. Don't solder LEDS & resistor through hole, just lightly on the pads edge to can exchange the resistor mainly. Monitor straight power on cold Vout also not to cross your application's max dangerous voltage zone.

 

[Salas]

Can I use the two DALE CPF3 2R and 1R5 in parallel 0R85 for R1 to set aprox. 0.73A with 0.82R R1?

Its 0.6V/R the current. With that you can calculate for any R1.

 

[merlin el mago]

Tea-Bag sent me one Dale cpf-2 1R 100ppm 2W, will be enough 600mA for my digital combo of 535mA?

 

[Salas]

Enough but little. I would parallel a 4R7 across it.

 

[merlin el mago]

I don't have quality 4R7 (100pppm 2W or more). What about if I use the two DALE CPF3 2R and 1R5 in parallel 0R85 for R1, 0.6/0.85=0.75A?