Hiya, I have placed my cd4046be and ne556n on my breadboard to creat two simple vcos, connected to a 0.2 watt small speaker to a 9v battery. The ne556n set up is similar to a atari punk but is louder than the vco on my cd4046be which is a pain. My quetion is how can I increase the volume on my cd4046be so it’s the same as my ne556n. I’m Wracking my brain on this one so any help would be most appreciated. Many thanks. P.S. please reply in untechnical info please as i’m new to all this, ha!
Can you post the schematic of the two vco circuits you’ve used?
Can you just add a potentiometer configured as a passive volume control after the ne556, and attenuate that output? Or are you set on increasing the volume of the cd4046be?
The CD4046 VCO output is a square wave between 0 V and VCC. Typically an NE556 oscillator output is a square/pulse wave between 0 V and VCC-1.5 V. So if both are running off the same power supply I’d expect the NE556 to be slightly less loud than the CD4046 if it’s a square wave, or much less loud if it’s a narrow pulse wave. Definitely seeing the schematics would help us understand better what the real situation is.
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I posted some pics of my simple vco 4046 breadboard and the schematic I got from 'Hackaday 4046 vco introduction.The speaker I’m using is a 0.2W plus a diagram of the 556 atari punk I’m using for the 556 vco. I did try the 4046 with a LM386N-1 but I couldn’t get it any louder. Thinking about it, to keep things simple I may just stick to logic based IC’s and a slightly louder speaker to compensate for the quieter logic chip. On the mod wiggler forum somebody said logic IC’s are quieter than the 556 IC’s.
As I’m going to make a noise box with built in speakers and an audio out for my computer, what would you suggest the best Wattage for a small speaker for my 4046 and other logic IC’s. Eventually I’m going to have two speakers either side of my synth box to create a bit of stereo for my new logic IC synth. I’ve already got two 0.5W in my other two 556 synths and they’ve worked great for the last 7 years, see my attachments. Many thanks for your ongoing help.
P.S. Can you point me in the right direction towards the best and safest layout for a LM386, Probably be easier for me to look at a diagram instead of a schematic but I’m slowing getting there
Hiya, I may just stick to logic chips, as the 556 IC’s are louder as suggested on the 'mod wiggler forum. I may run into volume complications so sticking to the logic IC’s may be simpler to work with. I posted some pictures below of the reference I’m using and some past 556 projects I’ve complerted. Could I use a louder mini speaker say a 1 or 2W directly to the 4046 chips or do I have to set up a LM386 circuit for it? Many thanks.
That doesn’t make sense to me, but I haven’t seen that discussion. Both should make square waves with amplitude close to VCC.
It appears you are trying to drive a speaker cone directly with your CD4046 and NE556. I don’t know how well that can be expected to work — speakers are very low impedance and these chips normally would drive a higher impedance, maybe the CD4046 has more trouble driving a speaker than an NE556. Using a speaker amplifier or buffer ought to take care of that.
The best way to find out how to use an LM386 is to look at the datasheet. TI’s is here. On page 10 they show a setup with gain 200, which is way more gain than you need. Page 8 shows a circuit with gain 20 — which is still way more than you need.
Really you only need unity gain (if not less!). You could use a voltage divider to attenuate your signal going into the LM386 with gain 20. It’s a little odd, cutting the amplitude and then amplifying it again, but the LM386 is designed to be able to drive speaker cones.
Or you could try a simple voltage follower with a TL07x op amp. That’s not ideal an ideal part for driving speakers but it might work well enough.
Or you could switch out your speaker cone for a powered speaker which can take a line signal; you’d probably want to attenuate the signal going to it.
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I had a look at page 10 of the schematic, so i’ll use that one for the 4046, thanks. As a coincidence I saw somebody make that one up on youtube last night. Regarding my other 556 projects I built, I connected two 0.5W mini speakers directly into the 556’s and they’ve worked fine. But maybe those quieter logic chips need a LM386? Could it damage my 4046 if I connect a slightly louder 1W directly to the 4046?
Many thanks.
Hey @transistorsunrise the system kinda is picking up your posts as spam. May I request that you condense your posts for the convenience of others going forward?
Hiya, sorry didn’t realise it was picking up as spam. I will condense them next time I make a post. Many thanks,
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