EA Trem successful! LED query...

[elevenoid]

Hi all,

I've just finished my second build sucessfully (first was the boost project) the EA Trem from runoffgroove on perfboard:

http://www.runoffgroove.com/eatremolo.html

After a couple of teething problems it now all works fine except I would like the LED to be a little brighter:

I assume I can do this by reducing the value of the 10k resistor, and will need to rebias Q1 as the LED will be pulling more power, but I wanted to check this, and also that changing this resistor value isn't going to do something else undesirable to the circuit??

Then I'll be fitting a switch for the half speed mod:
http://www.aronnelson.com/gallery/main.php/v/DRAGONFLY-LAYOUTS_0/The-Mod-Zone-_/EA_rate_mod.gif.html

Many thanks for any advice with this...

Ben

[Mark Hammer]

Just get yourself a brighter LED.

LEDs are rated in terms of millicandles.  So-called "garden variety" LEDs tend to be in the 600mcd or less range.  So-called "superbrights" can be easily gotten in the 2000-6000mcd range for pennies more.

Just note that the LED glows in opposite phase to the LFO.  That is, it gets brighter as the level goes down, and darker as the level goes up.  So you can tell what the overall rate is, but I wouldn't try syncing up your playing by looking at the LED for a couple seconds.

[jalien21]

Just get yourself a brighter LED.

http://www.dealextreme.com/details.dx/sku.2394

[elevenoid]

Just get yourself a brighter LED.

Thanks Mark,

I was thinking that might be easier, I'll check anyway to be sure, but am I right in thinking I will need to rebias with a different LED?

[Mark Hammer]

No, you won't need to.  At least I didn't need to.

[elevenoid]

update (for the archives more than anything else):

The superbright blue LED is almost blinding, and didn't seem to need any change to the Q1 bias...

excellent!