An unsuspecting quartz

Discontinued products Shruthi
#1

I’m creating this entry in hopes of helping others with similar problems, using keywords and such.
I had built the polivoks shruthi filter board without incident. Works great!
Then it was time for the control board. All went by the numbers. I intentionally limited my solder use, creating a very clean board!

Powered it up and …nothing….then a flick of light on occasion. I could touch parts of the board and leds would come on or off. Very ghost like. I checked what I could and resoldered everything. Nothing.
I read on here that somejuan was having a similar problem with leds acting eratic and decided it must be a bad quartz. The Oliver dude said it was unlikely; that he had done 50 with no quartz problems.

Online I could not find a clear way of testing the quartz, so I just replaced it….and viola’!
I knew my soldering was tight. Tight like a tiger!

Thanks all!

Shruthi Polivoks quartz eratic leds touching board

#2

Bear in mind that if you skimped on solder to have neat solder joints, you could have had a bad solder on the original quartz and not a faulty one.

#3

As the Oliv(i)er dude and Varthdader said, crystals have a high frequency of being OK (pun intended), soldering not.

#4

In fact i have done more bad soldering done than seen a bad quartz - the are all factory tested!

#5

Only bad crystal I ever saw as the dark one, but that was just user error.

#6

Gee, I never thought to check the soldering. I figured since the board didn’t work I should swap out the quartz. Silly me!