more vanishing point help!!

[ugly_guitar_guy]

Ok, so I just finished my circuit build of the vanishing point but it appears I've gone wrong somewhere. Here's a pic of what happens when power is wired up:



As you can see, only LED's 1,4, and 7 light up at the same time with no scrolling effect, and none of the switches do anything to change them. (I did the 4/6/8 mod, random switch, and reset switch, and used the layout from below, although I did it on perf board, not a custom etched circuit):



Does anyone have an idea of where I might have gone wrong? I checked all my connections and everything SEEMS to be in place according to the schem and the layout above. I tried getting a pic of the traces but it comes out very blurry. I'll keep trying though to see if that might help shed some light. Thanks guys!

[ugly_guitar_guy]

ok, got come clearer shots: Here's the solder side (flipped for ease of understanding):



Here'es the solder side with the layout overlay to compare my traces:



And here's the component side:



Help?

[MarcoMike]

that's quite hard to tell from here... but there's something strange at pins 9&10 of ic1... but i really don't remember much about this circuit... i could never get the random mode to work...

[ugly_guitar_guy]

Ok, so I found that the ground for Q1 wasn't soldered completely so I fixed that and now only one led comes on, but the strange part was that it was the last led, and then i let it sit for a few and tried it again and only the first led came on. So it appears to be cycling somehow, but i can't seem to figure it out...

[ugly_guitar_guy]

Ok, so I found that the ground for Q1 wasn't soldered completely so I fixed that and now only one led comes on, but the strange part was that it was the last led, and then i let it sit for a few and tried it again and only the first led came on. So it appears to be cycling somehow, but i can't seem to figure it out...

it's getting even more fun now. I looked at pins 9 and 10 like MarcoMike suggested and saw there might have been a slight solder connection so I re-soldered those and now leds 1, 3, and 7 come on. This is gonna be a pain in the ass debug, i know it...

[jacobyjd]

I had similar problems when breadboarding this thing--for some reason I could never get it to work. I ended up using a dual opamp LFO and a 4017 and called it a day--no random mode.

[ugly_guitar_guy]

I had similar problems when breadboarding this thing--for some reason I could never get it to work. I ended up using a dual opamp LFO and a 4017 and called it a day--no random mode.

Well truly the random mode is not that important to me. Maybe I'll have a sit down and figure it out without the random mode and go from there. I feel so close but so far away from this damn thing...

[jacobyjd]

If that's the case, you'll want to check out solderman's build report

[ugly_guitar_guy]

well i just went all the way to the basics of this circuit and bread boarded this schem:



And all I get is the first LED comes on and there's no cycling happening. I must be going wrong somewhere. Any help? Andrew?

[Skruffyhound]

There's something I'm not understanding here, did you flip one of the images in the  combi photo so that you could have the top side layout match the perf solder side. Which way did you flip it?  If you didn't do that then I'm going bonkers.
Whichever way round I turn it in my head I can't get Q4 to be in the same position on the board on both sides. Something is strange (of course it could always be me thats strange).

[Skruffyhound]

Aaaaarhhh, you took the picture in a mirror. That was extremely confusing for a while there. Interesting.
OK, I'm not being any help here so I'll move along. Good Luck

[ugly_guitar_guy]

Yeah, I inverted the photo to match in photoshop... 

Well, i've completely started over with a CMOS 555 for the clock with the 4017 and it seems to be working. Now I'm experimenting with cap and resistor values to get the speed how I want it.

I'm working off of this schem:



I'll keep ya posted. Thanks!