A bridge rectifier and a trimmpot question

[Guest domas]

What I found in the core description is:

B40C800        A bridge rectifier for 40V/800mA in a round package. Normaly such a rectifier is only necessary if the board is supplied with AC, but it is recommented to use it also with DC in order to prevent damage if the power lines are twisted. Optionally this rectifier can be replaced by 4 1N4001 diodes like shown in the circuit diagram.

But I cannot find a B40C800 nor 1N4001. Althought I have found a B80C800. Will it Okey? I will use an AC/DC adapter with 9 V and 500 mA. Also I have a question about the trimmpots. I cannot find any of these in my local store. And here what TT says:

10k        With this trimmpot the backlight luminance can be controlled.
P2       10k       This trimmpot controlls the LCD contrast

What could change these or could you give a more understandable description, is it a resistor that you can regulate(change the value) or something else. Please explain if you have time.

Thanks,

[pay_c]

For the first one: Yes, this will be ok. The number after the B tells you the maximum voltage it can take, the second after the C tells you the maximum current in mA.

For the second one: Yes, a trimpot (also called trimmer) is indeed an adjustable resistor. Just like a potentiometer, just in an small package. Every electrical store should certainly have them. If not: Go to a new one! really...

The backlight luminance should really be controlled by a trimpot or an potentiometer. For testing you can use a jumper (meaning a simple removable wire) between the pins. The backlight will be very bright then and will use up much power. But whatever... its just testing.

Normally the contrast pot can be totally exchanged by a jumper. The most LCDs are then most good visible. The same here: For testing, just a jumper. If the LCD goes all black, you know you need another trimpot.

Hope I could help u.

;D

[Guest domas]

Thanks, you really helped me. :D