SOLVED Looking for some help with the Caesar

[KR Sound]

Hello all- I assembled the Caesar over the weekend and while I'm getting some effect, I'm not getting any of the LEDs to light and the effect seems like it should be a bit more prevalent compared to what I've seen in demos.

Here are my IC values. The BBDs are from Cabintech and the other two are from Mouser I believe.

TL022	RC4558	V3207D - Delay	V3102D - Clock
3.5-5.5 4.38 3.8-5 0 4.38 3.24 3.8-4.5 8.8	4.56 4.69 4.45 0 4.51 4.57 4.57 9.12	0 4.34 3.84 8.2 8.8 4.33 5.12 5.12	8.8 4.33 0 4.34 0.09 8.69 2.47 8.22

I do have a 3386 in place of the 3362 trimpot for now, because that's what I had on hand, but I have the smaller one coming. I don't think this would be a problem because it functions correctly, it's just too big for the space. I believe the pinouts are the same.




Any help is greatly appreciated!

 

[Locrian99]

The leds won’t light in one of the switch positions, and they don’t light up real bright when they do, could be easily missed when lighting in a lit room.

Your 3207 voltages look good. Where do you have your blend pot set at when you are biasing? Could be you just have the blend set low that’s why it’s so subtle easy to do before you have knobs etc on there.

 

[Cybercow]

Based on the second photo, it appears that one of the LEDs may be incorrectly oriented. The "flat' spot (cathode - 'K') on both LEDs should be in the same direction, each oriented towards their respective square pads.

The physical size of the trimpot should have no bearing on the function. It's just a very narrow, tiny in fact, range of sweep for the "sweet spot".

Other than the VRefs and supply pins, I dunno about the voltage readings. I've not built a Caesar. The VRefs and supply pins appear to have correct voltages.

 

[KR Sound]

Based on the second photo, it appears that one of the LEDs may be incorrectly oriented. The "flat' spot (cathode - 'K') on both LEDs should be in the same direction, each oriented towards their respective square pads

Can’t believe I did that. My brain was thinking “Long-positive-square” and I rushed to get it finished.

Now to work on fine tuning the biasing.

Thanks so much!

 

[KR Sound]

Where do you have your blend pot set at when you are biasing? Could be you just have the blend set low that’s why it’s so subtle easy to do before you have knobs etc on there.

Where should my knobs ideally be set while biasing? I'll play with the blend knob and see what I get. Thanks

 

[Locrian99]

Where should my knobs ideally be set while biasing? I'll play with the blend knob and see what I get. Thanks

I’d probably just set it to the middle Myself. It’s been a bit since I built this but I feel like there was a thread with some directions on here when I did it.

 

[KR Sound]

I’d probably just set it to the middle Myself. It’s been a bit since I built this but I feel like there was a thread with some directions on here when I did it.

Right on- I'll search for that. Appreciate it.