harbinger one led was but stopped pulsing Solved

[Strassercaster]

hello i just upgraded my ldrs to the top of the line from small bear. it made a noticable difference for the better over the nsl7532. however i dont know what happened by my speed led has stopped pulsing. idk what i did but i no longer get a pulsing led which i did have working. any ideas where to start?


i bombed a transistor Q15 i guess i shorted it while working on it. however it never has flashed. before 11 oclock. any way to get this to flash when speeds are before 11 oclock.

[MAO]

FWIW, the LED doesn't flash at slower speeds on my build either. Haven't tried to address it yet as I'm still trying to dial in a decent sound. 

Curious how or what did the new LDRs improve on over the 7532s? 

[luks999]

hmm interesting, there seem to be a lot of issues with the harbinger LED
what could improve this situation is to decrease the base resistor of Q15 and increase the LEDs brightness by decreasing R54 (maybe a trimpot would be good here)

[luks999]

this threads also point to this issue:
http://www.madbeanpedals.com/forum/index.php?topic=21163.0
http://www.madbeanpedals.com/forum/index.php?topic=21221.0

for my old harbinger build i did the LED rate curcuit myself.
i connected the base of an 2n5088 transistor directly to pins1/2 of the speed pot.
worked well, the led worked on slower speed settings, so i guess it has something to do with the base resistor

[Strassercaster]

thanks luks. i will live with it on this one. i tested mine against a mojo vibe and a dunlop uv1 it won against the uv1 . it lost against the mojovibe before i upgraded the ldrs to the most expensive that small bear had.i thinks its identical to the mojo vibe now. on q13 i used the darlington mpsa13 and i got more speed of course brightness as well. Its just a tad slower than the others now but my firend put it on an oscilloscope and it was perfection, i am leaving this one as is. i do have plenty of parts to build a second one though and may do that after i get a few others checked off of the list. you guys rock thank you

[luks999]

that sounds interesting. im using the same parts for my upcoming harbinger :-)
and the lamp from smallbear

so do you have 2 leds or just one?
i may experiment with the led circuit

[MAO]

Do you have the LDRs flat or facing the lamp? Any chance you can post a video of the lamp in action?

I am having trouble getting mine to sound like a univibe, I seem to have huge range to adjust the lamp, but just doesn't sound like a univibe to me.

Have the advanced LDRs on order...

[Strassercaster]

thanks gentleman. luks999 i am using both leds one for on/off and the other to pulse but it is  dark from 8 oclock to 12 0clock


i started with the ldrs flat on the board and used a copper end cap but lined it with shinny aluminium tape. hard to describe how much better it sounds but it does. i now have the standing and facing the bulb. the bulb is very weak . this probably made more of a difference than the ldrs but it all works together. i discovered the less bright light upped the resistence  making the effect sound less like a pulsing vibrato and more phasey chewy univibe sounding. ill. do a sound clip and post it here for you in the next few days . i work 13 hour days and its hard to do it late at night because we have a 1 year old baby. i might get off early today if i do ill make you one i did post a clip of madbeans mojovibe bulb bias video. the hi low dark 200m ldrs covered sounded better than the uncovered i think even though they say they dont i disagree becasue the cover blocks more light making them higher in resistence . i could be wrong but it sounds just a tad better. of course i could have just dimmed the light even more i guess ha ha. i listend to your video sounded just like mine before i dimmed that light way back. now mine sounds better and chewyier than the dunlop UV-1 and thats no chump i thought it was as good as the mojo vibe an even match both are fantastic univibes as isnthe harbinger it should ge its an exact copy of the real deal. Brian (MR Madbean)does great work !