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v3205d's sound gritty pretty much no matter what you do. If you want clean, you need to buy a Lotto ticket some MN3005's

Aah! Thanks Alan. This is what I feared. Where to buy bona fida ones is the problem, though.
Any suggestions anyone?

Mark

P.S.  Dan, sorry for jumping in on your post!

Wow! you are a braver man than me if you are dabbling with mains and are unsure what you are doing! You did discharge the caps didn't you?

"Let's be careful out there"!

Mark

Wow! you are a braver man than me if you are dabbling with mains and are unsure what you are doing! You did discharge the caps didn't you?

"Let's be careful out there"!

Mark

Bollocks, things just get better on this site!

Mark

very neat looking builds! Does your DBD distort?

Mark

Surely, you are begging for "big knob" gags! Well, not from me. I just love the retro vibe. Nice one!

Mark

The most original build I have seen. How about some groovy lights?!

Mark

Very, very classy 

Very beautiful! Love the colour, love the etch. Sorry for the stupid question, but what is this a build of? I can't think of anything with 13 diodes. Also, what's the deal with the symetrical 3pdt PCBs?

Mark

...oops, did I say v3105, I meant v3205 of course

Anyway, I'm on route to solving this. first thing I did was map out all the nodes on the schematic and layout using coloured paint pens. This made it a lot easier to check continuity/solder bridges. To my amazement there were none (smug mode)!





Then checked value and orientation of all the components. Getting to R41 I found the problem: I'd placed a 3k9 resistor in place of a 39k (exit smug mode, curse those 5 band resistor codes and my failing eye sight)! Eureka! Finally working!

This, as many people have found, does distort a bit, however, it has such a sweet sound. So much so that couldn't stop playing all night and ended up with a reoccurence of my tendonitis.

I'm now working through the threads regarding this on the forum and will start socketing some of the mod suggestions to see if things get a bit less fizzy.

Anyway, although it was like looking at an enormous mountain in front of me, with patience and the little colour coded system I used I actually got a perverse pleasure out of the debugging process!

Lesson learned: 1) as mentioned on this forum by Midwayfair, amongst others, always use your DMM not your eyes to verify parts. 2) Take your time 3) drink lots of tea/coffee 4) don't despair, never give up!

Mark

I recently built a UV box which uses a whole network of 3 LEDs and one CLR. This is what I learnt from the web:

The first thing to do is to have a look at the spec sheet for the LED to see what the forward voltage is. Better still, knock up a little LED/ resistor circuit on a bread board using say, a 2k2 resistor to be on the safe side. Then, using your DMM, measure the voltage across each LED. Typically for a diffused red LED it's about 1.8v/2v. So, the voltage drop across 3 in series would be around 6v. the voltage drop across the CLR would be therefore be equal to the supply voltage minus 6v. I.e. 3v using a 9v supply. Another thing to know is that LEDs will require around 20 milliamps to fire them up.

So, using ohms law and the above info we can do this little sum:

R = V/I

R = 3/0.02

R =  150 ohms

I'm not sure if a 9v supply could work using 3 superbrights as the forward is usually a little over 3v. Experiment. My UV box is powered by 12v so not a problem.

Hope this helps, Mark

....and they say we don't live in a spiritual age :-P
Bloody brilliant!

Mark

Jon, your builds always make me smile!

Mark

Love your  knobs (ooh, err)! Love the decal and the appropriate chaos of the front!
Sweet sounding too. I can' get any video, though   Is that an iPad problem?

Nice one, Mark

P.S. How do I get rid of those smiley faces on the last post? I'm actually a miserable bastard!

Mark