- Welcome to Circuitbenders Forum.
Recent posts
#81
Drum machines / Re: Mattel Synsonics
Last post by ultramars - November 01, 2020, 06:50:14 AMhi everybody 
this mattel drum machines sound cool ! (litterally ^_^ )
is there a way to sync it externaly maybe?
this mattel drum machines sound cool ! (litterally ^_^ )
is there a way to sync it externaly maybe?
#82
Repair advice & questions. / Guitar Amplifier noise when a ...
Last post by bzomb - October 26, 2020, 12:06:37 PMHello!
I've built a guitar amp with two LM386...its acctually a kit that I bought to put together. Its powered by a 9V battery but also you can plug it to the wall. The thing is that when I plug the power adapter there is a stong humming signal. I tried one cheap 9V 1A and a good quality 9V 2A and its all the same, noisy. I've been told that it must be the power adapter thats causing the problem and I need to add a "Noise filter" but I have no idea how to (very new in this)
Anyone can provide any information about how can I solve this issue?
Thank you!
I've built a guitar amp with two LM386...its acctually a kit that I bought to put together. Its powered by a 9V battery but also you can plug it to the wall. The thing is that when I plug the power adapter there is a stong humming signal. I tried one cheap 9V 1A and a good quality 9V 2A and its all the same, noisy. I've been told that it must be the power adapter thats causing the problem and I need to add a "Noise filter" but I have no idea how to (very new in this)
Anyone can provide any information about how can I solve this issue?
Thank you!
#83
Repair advice & questions. / Telephone Microphone Circuit B...
Last post by bzomb - October 26, 2020, 12:05:02 PMHi everyone!
I've made a "Telephone Microphone" that is fairly simple to make, just use the two wires from the earpiece of the phone and solder them to a guitar jack and thats it. The thing is that I tried to add a lowpass filter with a 100K potentiometer and its correspondant capacitor (to roll of a bit of the highend freq. so it doesn't feedback, and the problem is that when I turn down the pot, it stats to hum. I've tried different wirings, use shielded wire, and NOTHING.
So, then I tought it was a good idea to get rid of the pot and use a ON/ON switch and add the RC filter to it so you can select between the "normal" telephone sound signal or the filtered signal. Aaaaand it didn't work. I'm using a 3.5K resistor with a 0.047mF capacitor, wich in theory will result in a cuttoff freq of 900Hz, more than enough to me, but it doesn't affect the signal at all! When I use the potentiometer, I added a 47pF capacitor and it works, but, as I said above, IT HUMS. I tried to solder the resistor and capacitor directly to the jack and, nothing...
The earpiece has a very low reading, a 20 ohm, so maybe that causes the problem or I don't know. I've seen other people add a volume or filter pots to this phones and they just work fine! (of course I've ask them but got no answer back) I also tried on 3 different phones and the result is the same.
Also, I must tell you that I'm very new at this and I still don't know how to read schemantis propperly, so be pacient please haha.
Anyways, hope you can help!
Thank you!
I've made a "Telephone Microphone" that is fairly simple to make, just use the two wires from the earpiece of the phone and solder them to a guitar jack and thats it. The thing is that I tried to add a lowpass filter with a 100K potentiometer and its correspondant capacitor (to roll of a bit of the highend freq. so it doesn't feedback, and the problem is that when I turn down the pot, it stats to hum. I've tried different wirings, use shielded wire, and NOTHING.
So, then I tought it was a good idea to get rid of the pot and use a ON/ON switch and add the RC filter to it so you can select between the "normal" telephone sound signal or the filtered signal. Aaaaand it didn't work. I'm using a 3.5K resistor with a 0.047mF capacitor, wich in theory will result in a cuttoff freq of 900Hz, more than enough to me, but it doesn't affect the signal at all! When I use the potentiometer, I added a 47pF capacitor and it works, but, as I said above, IT HUMS. I tried to solder the resistor and capacitor directly to the jack and, nothing...
The earpiece has a very low reading, a 20 ohm, so maybe that causes the problem or I don't know. I've seen other people add a volume or filter pots to this phones and they just work fine! (of course I've ask them but got no answer back) I also tried on 3 different phones and the result is the same.
Also, I must tell you that I'm very new at this and I still don't know how to read schemantis propperly, so be pacient please haha.
Anyways, hope you can help!
Thank you!
#84
Repair advice & questions. / VSS30 Sample Distorting Issue ...
Last post by simon_whitehead - October 14, 2020, 12:24:16 PMHi all,
I've stumbled upon a problem with my VSS30 whereby any samples captured with the internal mic are distorted and have a sort of ground hum on them. Samples captured via the RCA are not distorted.
Here's a quick vid to show the issue. You'll see everything seems to work fine until I record something via the mic: https://youtu.be/OEH2ixMYLFQ
I recently installed a midi-retrofit into the unit although everything was working fine for a few days after - I'm unsure whether it's coincidence or could be linked.
Here's a pic of the midi-retrofit install in case it could help > https://www.dropbox.com/s/hl38w7687antk82/VSS30%20Retrofit.JPG?dl=0
Any help is hugely appreciated! I do have a spare mic to hand if that sounds like the culprit but I'm keen to hear thoughts/advice on any other possibilities.
Thanks in advance
Simon
I've stumbled upon a problem with my VSS30 whereby any samples captured with the internal mic are distorted and have a sort of ground hum on them. Samples captured via the RCA are not distorted.
Here's a quick vid to show the issue. You'll see everything seems to work fine until I record something via the mic: https://youtu.be/OEH2ixMYLFQ
I recently installed a midi-retrofit into the unit although everything was working fine for a few days after - I'm unsure whether it's coincidence or could be linked.
Here's a pic of the midi-retrofit install in case it could help > https://www.dropbox.com/s/hl38w7687antk82/VSS30%20Retrofit.JPG?dl=0
Any help is hugely appreciated! I do have a spare mic to hand if that sounds like the culprit but I'm keen to hear thoughts/advice on any other possibilities.
Thanks in advance
Simon
#85
BENDING TIPS / Re: 555 as a lfo trigger circu...
Last post by wax+wire - October 11, 2020, 06:34:00 AMSo, I think you can just connect the base of an NPN transistor to pin 3 of the 555, and then connect the other two legs of the NPN transistor to the points you want to connect.
However, from my understanding, this may not create a "pure bend" (i.e. 0 ohm, pure conductive, no resistance connection). To do that you could use a reed relay
However, from my understanding, this may not create a "pure bend" (i.e. 0 ohm, pure conductive, no resistance connection). To do that you could use a reed relay
#86
BENDING TIPS / Re: 555 as a lfo trigger circu...
Last post by flyagaricus - October 10, 2020, 05:30:51 PMBUMP - I'd like some info on this as well
#87
BENDING TIPS / Tips on intsalling the LTC1799...
Last post by flyagaricus - October 10, 2020, 05:29:11 PM*EDIT:* Seems I can't attach photos 
Hi All
I'm planning my first bend and I'm pretty new to electronics in general. I picked up an old Casio MT-140 for cheap and I'm preparing to bend it.
I think I've isolated an adjustable coil as the clock source. I would like to replace it with the LTC1799 module I've bought here.
I was hoping before I start, maybe there's someone that has direct experience with this keyboard and coil that cound share some tipe before I 'have at 'er'.
I've attached a photo of the coil on both sides of the board. I jut don't really know which pins are which, or even how many pins the coil has as it's so close to the board. It looks like it's either 4 or 6?
Thanks!
Hi All
I'm planning my first bend and I'm pretty new to electronics in general. I picked up an old Casio MT-140 for cheap and I'm preparing to bend it.
I think I've isolated an adjustable coil as the clock source. I would like to replace it with the LTC1799 module I've bought here.
I was hoping before I start, maybe there's someone that has direct experience with this keyboard and coil that cound share some tipe before I 'have at 'er'.
I've attached a photo of the coil on both sides of the board. I jut don't really know which pins are which, or even how many pins the coil has as it's so close to the board. It looks like it's either 4 or 6?
Thanks!
#88
circuitbenders.co.uk CB55 - DIY Boss DR55. / Re: Olegtron 4060 mk2 - good c...
Last post by channelite - October 05, 2020, 03:26:28 AM #89
circuitbenders.co.uk CB55 - DIY Boss DR55. / Re: Olegtron 4060 mk2 - good c...
Last post by channelite - August 28, 2020, 12:22:48 AM #90
Synths & Samplers / SUT HEKSENS NEGL Optocoupling ...
Last post by kloroplaster - August 24, 2020, 09:54:36 PMHi!
I've made an eurorack module called HEKSENS NEGL!.
Heksens Negl has 8 identical optocoupler circuits that lets you interface external button presses safely with your eurorack.
If you are into circuit bending this is a very practical way of controlling things without having to worry about unwanted electrical interference between different power systems.
All you need to do is to break out the two points that needs to connect in order to activate a button/bend and connect them to a jack, patch a cable from there to one of the upper output jacks on Heksens Negl and you are ready to go!
Please check this video:
https://vimeo.com/429893115
Full kit is 50$ + shipping
I've made an eurorack module called HEKSENS NEGL!.
Heksens Negl has 8 identical optocoupler circuits that lets you interface external button presses safely with your eurorack.
If you are into circuit bending this is a very practical way of controlling things without having to worry about unwanted electrical interference between different power systems.
All you need to do is to break out the two points that needs to connect in order to activate a button/bend and connect them to a jack, patch a cable from there to one of the upper output jacks on Heksens Negl and you are ready to go!
Please check this video:
https://vimeo.com/429893115
Full kit is 50$ + shipping