I am interested, how to decoding Call Progress using esp32 without extra ic tone decoder eg. cmx673, cmx683, and so on
@gadgetsideload3 күн бұрын
Goertzel algorithm libraries might be able to decode the frequencies in the audio but I’ve never tried it and some people have found it to be inconsistent. Maybe if the chip is doing too many other things it could be even less reliable to the point where you need a separate chip anyway. www.hackster.io/MM_Shoaib/dtmf-decoder-using-only-arduino-872502
@CAXRAMEDIA3 күн бұрын
@@gadgetsideload I have successfully detected DTMF with Goertzel. However, for Call Progress, I still depend on CMX673, I would be very grateful if you could create a library to detect Call Progress Tone, especially to detect Bussy Tone, and Hello Voice :-)
I followed the PTC schematic before I found your video and I immediately get a 2.5V drop on my 5V rail after you connect it to the chip. Any ideas on what I’m doing wrong? Is it worth troubleshooting or should I just look into a chip analysis like you described here. Much appreciated!
@gadgetsideload10 күн бұрын
if the main voltage supply rail is being dragged down dramatically when something is connected it sounds like a short circuit or bad component drawing excessive current.
@rubenmejia488110 күн бұрын
Try re capping the console that might take care of it.
@AnotherMaker15 күн бұрын
Very thorough. That punchdown holder is pretty essential. It really sucks to have that punchdown slip and go into your palm.
@DontEatFibreАй бұрын
So my RX is 5V as well, while the TX is 3.3v This is when powering from USB. Powering from 3V3, RX is 2.6V and TX is 3.3V.
@DontEatFibreАй бұрын
If someone can tell if the RX dropping that low is to be expected while not transmitting, please let me know.
@gadgetsideloadАй бұрын
is that while applying 3.3 V to the Vin pin? and is that with a CH 340 chip? I think the module vin pin is intended to take higher than 3.3 V so the onboard regulator can bring it down to 3.3 but I’m not sure if the regulator on these modules just passes through 3.3 in to out without a drop out. having 2.6 on the Rx pin is definitely not normal and it’s around the bottom threshold for detecting logic high which I think is 2.65 V when running at 3.3 V so it definitely needs to be run differently to get that back to 3.3 V.
@diyertimeАй бұрын
I usually buy the versions that use an external antenna so that I have some freedom to get better signal coverage.
@silverback3633Ай бұрын
Very good explanation. USB IC provides the level shifting when it is connected to a 5V USB port. Why CH340 is connected to 5V? Doesn't cost anything, in fact they could have saved those 2 resistors. About the RSSI, would like to see the difference between the original modules from ESSPRESSIF and the clones.
@mikejones-vd3fgАй бұрын
Nice find, clever fix, interesting mystery...
@GnuReligion2 ай бұрын
Long rows of pins with ABS plastic on top ... oh so hard to un-solder. Happy to find your 2nd channel!
@gadgetsideload2 ай бұрын
I think I started this channel 3 years ago and originally it was just a parking spot for extra long schematic or software discussion that would not really fit in a regular video but now I’m not even sure if I should actually put proper content of certain project categories on here as well so I’m letting it evolve on its own.
@Bianchi772 ай бұрын
Creative video, thank you :)
@whitneydesignlabs87382 ай бұрын
Thanks much. Very cool. I have an old crank style phone, a dial wall phone, some old modems, and some 8 bit computers. I'd like to set up my own phone system for testing and demonstration of this equipment. Calls, ringing phones, BBS on Apple ][ etc... Is your board available as a kit from JLPCB or PCBway?
@gadgetsideload2 ай бұрын
The project is shared on PCBway www.pcbway.com/project/shareproject/Phone_Line_Simulator_POTS_Land_Line_1d34078f.html The one component they seem to have trouble sourcing is the 600 ohm transformer because I just buy them on eBay or AliExpress so when people buy the assembled project there, I think they have to just tell them don’t put the transformer and people solder one in themselves.
@whitneydesignlabs87382 ай бұрын
@@gadgetsideload Thanks I submitted an order for 5 units to your link. It is being reviewed for assembly now. I made note of omitting the 600 ohm transformer if it was not stocked. I will let you know how it goes.
@gadgetsideload2 ай бұрын
I am also currently working on another accessory board where if it works, several of these can be plugged into it so that calls can be made between multiple boards at the same time or even party line multiple notes together. if that goes well I could be making a video within the next two months for it.
@user-ww1go3hz7n2 ай бұрын
Thank you this was amazingly helpful and a good speed for me :) not too fast and very clear <3
@noggin732 ай бұрын
I much prefer Visual Studio code with the PlatformIO plugin. Arduino code still works with minor changes. None of this digging through a 100 menus to find the correct CPU/programmer!
@TheEmbeddedHobbyist2 ай бұрын
Are we talking WS2812B style LED's here? I do love using the little chips. I just write my own bit-bang drivers for these, unless the chip has some form of DMA output.
@gadgetsideload2 ай бұрын
These were 2812 but I’m also hoping to get SK 6812 working
@TheEmbeddedHobbyist2 ай бұрын
@@gadgetsideload The SK6812's should not be a problem as they are identical to the WS2812B's, the SK3612RGBW just need a 4 byte buffer instead of a 3 byte buffer per pixel. Not a problem if your bit banging.
@BusyElectrons2 ай бұрын
I've had good luck with the ButtonWorx repair kits (on Amazon). They're self-adhesive and they stick to the PCB instead of the button. They have a thin spacer built in that keeps the conductive pad just above the surface of the PCB. Remotes I repaired around 2 years ago are still working fine under daily use.
@3167282372 ай бұрын
Why sometimes LTSpice simulations very slow, maybe you know how to speed up the simulations?
@BusyElectrons2 ай бұрын
Interesting take on a custom ATtiny breakout board. You exposed the three most common serial interfaces, added onboard TTL serial to USB, and broke out the remaining four I/O pins. I could see how that could be useful for generic experimentation using this ATtiny series. Cool!
@gadgetsideload2 ай бұрын
it has turned out to be more useful than I originally anticipated, I think I made it close to two years ago and I’m always finding uses for it.
@gregoryko70763 ай бұрын
Can I buy this PCB somewhere? Is the source code and diagram for this PCB available somewhere?
@gadgetsideload3 ай бұрын
PCBs are available here and there’s a link to code and project files on GitHub there. if a board is purchased as an assembled unit I think it just comes with header sockets and people provide their own processor to plug-in. www.pcbway.com/project/shareproject/USB_Adapter_for_Arcade_Trackball_Spinner_and_LS30_Rotary_Joysticks_ad53cf0e.html
@Larry_Welsh3 ай бұрын
I was not able to locate the I2S.h, thus had zero luck with the sketch. Still wish I could get your previous effort working on the mega, it really works nice on the uno. thanks for sharing!
@HosseinFatehi-tc7yp3 ай бұрын
Good job . I want to build a dtmf dialer by esp8266 and i use tone to build 2 frequencies on 2 pins but when i dial by it , wrong number message heared. Can you help me to solve this problem?
@bobnine3 ай бұрын
Best to check the battery and check your camera can film infra red leds first 😂
@TheEmbeddedHobbyist3 ай бұрын
Just a thought, superglue might be a bit brittle for this kind of use. I might try some form of rubber contact glue it's a bit more flexible Superglue is no good in shear type force, so any flexing could lead to the joint parting ways.
@gadgetsideload3 ай бұрын
I was considering contact cement but the small tube I had was all dried up, I probably bought it 15 years ago and used it once for whatever I bought it for at the time so I’ll consider this an ongoing experiment for type of glue. It will at least only get gentle use around here.
@pileofstuff3 ай бұрын
Great simple repair. I gotta get me a box of those replacement pads - there's a couple of remotes around here that haven't responded to just cleaning them.
@gadgetsideload3 ай бұрын
Definitely start by looking at the IRLED in the camera to confirm the buttons are not responding because I still have one remote for a receiver from the 90s where the power button stopped responding in the past week, but the LED is actually transmitting. I tried gluing a new pad on just to see and it did not change anything so I’m not even sure what’s going on with that one, the power button on the receiver works but just not from the remote for some reason.
@jordantekelenburg4 ай бұрын
Where would I find the filter calculator??
@hansvandijk39374 ай бұрын
Great product, I was looking for this . We should work together.
@madiankhalil74245 ай бұрын
For MacBook how can I open top dictionary?
@pdegroote5 ай бұрын
at 7:20 you ask what it means: "Any not specified set to 000". It simply means taht whatever register is not in the list, you set it to 000. So all unused registers to 0.
@user-ms3cd9lp9l5 ай бұрын
its not working. i used ay 3 8912 i only hear clicks and 1 one at the end
@sushiplus70585 ай бұрын
Helped with my simulation homework, thank you!
@velvetsound5 ай бұрын
Funny I was thinking about doing this. It’s essentially a GigRig G2 perhaps?
@gadgetsideload5 ай бұрын
similar concept but I believe they use completely passive relays to switch unless other buffers are activated for things like splitting the signal chain into multiple paths. So doing it with semiconductor analog switches like this matrix here can possibly affect the signal path. I didn’t notice anything detrimental at amateur home volumes.
@gulafshabhatti94105 ай бұрын
i could only find transient.cir file and thats not working. I cant find model file for lm358. please sir share it please
@LabSkaterPussies5 ай бұрын
Fascinating stuff. The only thing that I am struggling with is the multiple waves. In the case that both sine waves are at their peak and you add them together, you will be outside of the DACs range. In analog synthesis, if you pass an op amp's range the signal will clip. I didn't really get what the equivalent was of this in digital synthesis. You shift each data point by one bit, so essentially dividing by 2 before adding correct? This way it won't exceed the DACs range? And if you wanted to use 3 waves you would have to divide the values by 3? Doesn't this decrease the resolution of the wave because when you divide you may be rounding values off? Or does it not matter because once you add them back together you still use the full range of the DAC?
@LabSkaterPussies5 ай бұрын
Also, in generating sawtooth waves below 500Hz, do you think a filter would be able to create a sharp enough wave but where you can't see the steps
@Pixelwaster5 ай бұрын
In this little field of Poppies, Poppies, Poppies, Poppies, ..... Found several of these while attempting to inventory my junque (box?, room? area?) again. Or still for the last 20 years. it breeds.
@gadgetsideload5 ай бұрын
I just started officially sorting out my junk box that has been going for decades maybe over 30 years that’s my cut off for choosing to remember how long I have been hoarding parts. I have so many weird chips that I don’t even know anymore what they do and I’ve been googling them. It might lead to some interesting breadboard projects.
@pileofstuff5 ай бұрын
Looking forward to the inevitable guitar pedal implementation.
@gadgetsideload5 ай бұрын
The hardest part will be finding a way to tape down a guitar cable to the workbench without dragging a breadboard and everything else on the floor
@Pixelwaster4 ай бұрын
@@gadgetsideload Drywall screws.
@reg25905 ай бұрын
Following this series avidly as it evolves - thanks.
@reg25905 ай бұрын
I've watched all of your "episodes" in making this and I love it! I originally came to see how I could make an "old" phone tester, testing pulse dial or DTMF to BCD so to display the dialed number on a 7 segment display; .also using the SLIC just to provide ringing current. Now I may make a phone to phone demo board of my own! You sir, have expanded my horizon; thank you so much. Incidently in the UK we call the Central Office the Exchange. Also watching earlier " episodes" it struck me that perhaps you could hive off the service signal generation to another processor and just call the tones as required...
@gadgetsideload5 ай бұрын
I’m currently ordering more parts to try some more things out including making a sort of expansion switching matrix where a bunch of exchanges can all plug-in and it will have its own way of routing calls between several different nodes, so there could be multiple separate calls in place or even party lines with more than two on the same circuit. I’ve been working on it more than five years at this point so the ideas keep coming.
@skrame015 ай бұрын
The stand works if you place the groove on the iron just above the nut onto the notch in the stand plate.
@jeffreyjhouser6 ай бұрын
Thanks for this video, it was helpful and cleared up some confusion about how to import symbol parameters into a file!
@AnalogDude_6 ай бұрын
Awesome information and video.
@rickjljr116 ай бұрын
Isn't the second circuit, the band amplifying filter, just an oscillator? How do you stop it from doing that? The Twin T has a 180 deg phase shift, the op-amp inverts the signal, another 180 deg and it has plenty of gain. 2 pi around the loop and gain >1.
@gadgetsideload6 ай бұрын
In a more complete implementation of that circuit as a filter there's another feedback path added. In this video I used it as a Wah filter effect and then modified it to force oscillations (first step toward drum synth) kzread.info/dash/bejne/pWqJltaHj73YcpM.html
@mohameddrissi10757 ай бұрын
hello friend , thanks for the quality video . I'm trying to simulate an electret mic + its noise and i wanna add this noise to the simulation by injecting the noise spectral density into a noise generator ! is there a way to do that ?
@user-sj7hw8td2q7 ай бұрын
Hello. My soldering station 8898 no longer displays the soldering iron temperature display correctly. The lower limit is 356. The upper limit is 932. Although it should be from 180 to 500. When turned on, it shows not 352 degrees, but 662. The soldering iron itself works. The hair dryer display shows the temperature correctly. Can you tell me what elements might have broken? What should I check?
@steverodgers11127 ай бұрын
These SLICS would have depended on a codec's bandpass filter to filter out things outside of the voice band, as SLICS would have typically been connected to to a codec/filter and then to a TDM PCM highway for digital switching. If you are going to directly connect one of these to another SLIC, then external filtering would be required. As far muting the output during ringing, couldn't that be done by using a crosspoint switch matrix (e.g. MT8816) to connect the audio path to other SLICS and to the ESP32? The only thing which could be an issue is the spikes coupling through the crosspoint switch during ringing due to their fast rise times, but might be able to be solved with an RC snubber at the output of the bandpass filter.
@newburypi7 ай бұрын
I'm looking forward to you completing this project.
@gadgetsideload7 ай бұрын
There may be big progress sometime this weekend if no big problems show up.
@Poppy-ub3zb7 ай бұрын
Can both soldering iron and hot air be used actively at the same time? Is the insulate wire high heat tolerance? if I accidentally touch the soldering iron on it, will it melt?
@gadgetsideload7 ай бұрын
I always use the iron and hot air at the same time for example if I just made a solder connection and I have heat shrink tubing, I put the tubing in position after and just pick up the hot air tool and shrink that and then go back to soldering with everything active. another thing I sometimes have to do is make some through hole solder connections on a breakout board and then there’s a small surface mount part as well so I pick up the hot air tool and heat that up and then just go back to the soldering iron. I don’t know if the wire jacket is heat resistant, I’d rather only find out by accident instead of testing it out and finding its vulnerable but I’ve had it almost 3 years and I haven’t had an incident
@HeyBirt7 ай бұрын
Thanks for all of your hard work on this! I think I might build a couple of boards of your design to use as a starting point for a slightly different take. It seems that each node could support more than one phone line, more like a central office. Another idea is using a RJ45 interconnect between nodes. The four pairs of wires in the RJ45 (ethernet cable) would be enough for the RS-485 control link as well as two phones (if someone did not want to use WiFi for the control link) or 4 phones plus WiFi for control link. Of course, as you say the WiFi also provides the possibility of 'wireless' nodes. Good work!
@gadgetsideload7 ай бұрын
I am working on an idea to make an expansion board where each node can have its RJ 11 cable going to a matrix board with at least four channels so then that can become more of the central office controlling who gets routed to which node so I’m going to be experimenting over the next couple of months with that.
@stronggers7 ай бұрын
ctrl+ right click on the component to gain access to the Component Attribute Editor FYI
@upendownlinker5 ай бұрын
thanks bro
@CARlosDAN7838 ай бұрын
Hello friend, I am investigating the ripple noise from the output of car alternators, especially 12 and 24 volt alternators, I have seen some videos of what the outputs of these alternators are like and I wanted to see if I can simulate them. with LtSpice, and with your video I have come to the conclusion that I can. Your video has been very helpful to me, that's why you earned my subscription and hands up. Greetings from my beautiful Venezuela.
@newburypi8 ай бұрын
Beautiful :)
@pileofstuff8 ай бұрын
Jenny!
@gadgetsideload8 ай бұрын
she’s back, and she’ll be making a few more appearances.
Пікірлер
I am interested, how to decoding Call Progress using esp32 without extra ic tone decoder eg. cmx673, cmx683, and so on
Goertzel algorithm libraries might be able to decode the frequencies in the audio but I’ve never tried it and some people have found it to be inconsistent. Maybe if the chip is doing too many other things it could be even less reliable to the point where you need a separate chip anyway. www.hackster.io/MM_Shoaib/dtmf-decoder-using-only-arduino-872502
@@gadgetsideload I have successfully detected DTMF with Goertzel. However, for Call Progress, I still depend on CMX673, I would be very grateful if you could create a library to detect Call Progress Tone, especially to detect Bussy Tone, and Hello Voice :-)
@@gadgetsideload kzread.info/dash/bejne/oq1q17azipOdmaQ.htmlsi=AyFb04gPjdhGzUfz
I followed the PTC schematic before I found your video and I immediately get a 2.5V drop on my 5V rail after you connect it to the chip. Any ideas on what I’m doing wrong? Is it worth troubleshooting or should I just look into a chip analysis like you described here. Much appreciated!
if the main voltage supply rail is being dragged down dramatically when something is connected it sounds like a short circuit or bad component drawing excessive current.
Try re capping the console that might take care of it.
Very thorough. That punchdown holder is pretty essential. It really sucks to have that punchdown slip and go into your palm.
So my RX is 5V as well, while the TX is 3.3v This is when powering from USB. Powering from 3V3, RX is 2.6V and TX is 3.3V.
If someone can tell if the RX dropping that low is to be expected while not transmitting, please let me know.
is that while applying 3.3 V to the Vin pin? and is that with a CH 340 chip? I think the module vin pin is intended to take higher than 3.3 V so the onboard regulator can bring it down to 3.3 but I’m not sure if the regulator on these modules just passes through 3.3 in to out without a drop out. having 2.6 on the Rx pin is definitely not normal and it’s around the bottom threshold for detecting logic high which I think is 2.65 V when running at 3.3 V so it definitely needs to be run differently to get that back to 3.3 V.
I usually buy the versions that use an external antenna so that I have some freedom to get better signal coverage.
Very good explanation. USB IC provides the level shifting when it is connected to a 5V USB port. Why CH340 is connected to 5V? Doesn't cost anything, in fact they could have saved those 2 resistors. About the RSSI, would like to see the difference between the original modules from ESSPRESSIF and the clones.
Nice find, clever fix, interesting mystery...
Long rows of pins with ABS plastic on top ... oh so hard to un-solder. Happy to find your 2nd channel!
I think I started this channel 3 years ago and originally it was just a parking spot for extra long schematic or software discussion that would not really fit in a regular video but now I’m not even sure if I should actually put proper content of certain project categories on here as well so I’m letting it evolve on its own.
Creative video, thank you :)
Thanks much. Very cool. I have an old crank style phone, a dial wall phone, some old modems, and some 8 bit computers. I'd like to set up my own phone system for testing and demonstration of this equipment. Calls, ringing phones, BBS on Apple ][ etc... Is your board available as a kit from JLPCB or PCBway?
The project is shared on PCBway www.pcbway.com/project/shareproject/Phone_Line_Simulator_POTS_Land_Line_1d34078f.html The one component they seem to have trouble sourcing is the 600 ohm transformer because I just buy them on eBay or AliExpress so when people buy the assembled project there, I think they have to just tell them don’t put the transformer and people solder one in themselves.
@@gadgetsideload Thanks I submitted an order for 5 units to your link. It is being reviewed for assembly now. I made note of omitting the 600 ohm transformer if it was not stocked. I will let you know how it goes.
I am also currently working on another accessory board where if it works, several of these can be plugged into it so that calls can be made between multiple boards at the same time or even party line multiple notes together. if that goes well I could be making a video within the next two months for it.
Thank you this was amazingly helpful and a good speed for me :) not too fast and very clear <3
I much prefer Visual Studio code with the PlatformIO plugin. Arduino code still works with minor changes. None of this digging through a 100 menus to find the correct CPU/programmer!
Are we talking WS2812B style LED's here? I do love using the little chips. I just write my own bit-bang drivers for these, unless the chip has some form of DMA output.
These were 2812 but I’m also hoping to get SK 6812 working
@@gadgetsideload The SK6812's should not be a problem as they are identical to the WS2812B's, the SK3612RGBW just need a 4 byte buffer instead of a 3 byte buffer per pixel. Not a problem if your bit banging.
I've had good luck with the ButtonWorx repair kits (on Amazon). They're self-adhesive and they stick to the PCB instead of the button. They have a thin spacer built in that keeps the conductive pad just above the surface of the PCB. Remotes I repaired around 2 years ago are still working fine under daily use.
Why sometimes LTSpice simulations very slow, maybe you know how to speed up the simulations?
Interesting take on a custom ATtiny breakout board. You exposed the three most common serial interfaces, added onboard TTL serial to USB, and broke out the remaining four I/O pins. I could see how that could be useful for generic experimentation using this ATtiny series. Cool!
it has turned out to be more useful than I originally anticipated, I think I made it close to two years ago and I’m always finding uses for it.
Can I buy this PCB somewhere? Is the source code and diagram for this PCB available somewhere?
PCBs are available here and there’s a link to code and project files on GitHub there. if a board is purchased as an assembled unit I think it just comes with header sockets and people provide their own processor to plug-in. www.pcbway.com/project/shareproject/USB_Adapter_for_Arcade_Trackball_Spinner_and_LS30_Rotary_Joysticks_ad53cf0e.html
I was not able to locate the I2S.h, thus had zero luck with the sketch. Still wish I could get your previous effort working on the mega, it really works nice on the uno. thanks for sharing!
Good job . I want to build a dtmf dialer by esp8266 and i use tone to build 2 frequencies on 2 pins but when i dial by it , wrong number message heared. Can you help me to solve this problem?
Best to check the battery and check your camera can film infra red leds first 😂
Just a thought, superglue might be a bit brittle for this kind of use. I might try some form of rubber contact glue it's a bit more flexible Superglue is no good in shear type force, so any flexing could lead to the joint parting ways.
I was considering contact cement but the small tube I had was all dried up, I probably bought it 15 years ago and used it once for whatever I bought it for at the time so I’ll consider this an ongoing experiment for type of glue. It will at least only get gentle use around here.
Great simple repair. I gotta get me a box of those replacement pads - there's a couple of remotes around here that haven't responded to just cleaning them.
Definitely start by looking at the IRLED in the camera to confirm the buttons are not responding because I still have one remote for a receiver from the 90s where the power button stopped responding in the past week, but the LED is actually transmitting. I tried gluing a new pad on just to see and it did not change anything so I’m not even sure what’s going on with that one, the power button on the receiver works but just not from the remote for some reason.
Where would I find the filter calculator??
Great product, I was looking for this . We should work together.
For MacBook how can I open top dictionary?
at 7:20 you ask what it means: "Any not specified set to 000". It simply means taht whatever register is not in the list, you set it to 000. So all unused registers to 0.
its not working. i used ay 3 8912 i only hear clicks and 1 one at the end
Helped with my simulation homework, thank you!
Funny I was thinking about doing this. It’s essentially a GigRig G2 perhaps?
similar concept but I believe they use completely passive relays to switch unless other buffers are activated for things like splitting the signal chain into multiple paths. So doing it with semiconductor analog switches like this matrix here can possibly affect the signal path. I didn’t notice anything detrimental at amateur home volumes.
i could only find transient.cir file and thats not working. I cant find model file for lm358. please sir share it please
Fascinating stuff. The only thing that I am struggling with is the multiple waves. In the case that both sine waves are at their peak and you add them together, you will be outside of the DACs range. In analog synthesis, if you pass an op amp's range the signal will clip. I didn't really get what the equivalent was of this in digital synthesis. You shift each data point by one bit, so essentially dividing by 2 before adding correct? This way it won't exceed the DACs range? And if you wanted to use 3 waves you would have to divide the values by 3? Doesn't this decrease the resolution of the wave because when you divide you may be rounding values off? Or does it not matter because once you add them back together you still use the full range of the DAC?
Also, in generating sawtooth waves below 500Hz, do you think a filter would be able to create a sharp enough wave but where you can't see the steps
In this little field of Poppies, Poppies, Poppies, Poppies, ..... Found several of these while attempting to inventory my junque (box?, room? area?) again. Or still for the last 20 years. it breeds.
I just started officially sorting out my junk box that has been going for decades maybe over 30 years that’s my cut off for choosing to remember how long I have been hoarding parts. I have so many weird chips that I don’t even know anymore what they do and I’ve been googling them. It might lead to some interesting breadboard projects.
Looking forward to the inevitable guitar pedal implementation.
The hardest part will be finding a way to tape down a guitar cable to the workbench without dragging a breadboard and everything else on the floor
@@gadgetsideload Drywall screws.
Following this series avidly as it evolves - thanks.
I've watched all of your "episodes" in making this and I love it! I originally came to see how I could make an "old" phone tester, testing pulse dial or DTMF to BCD so to display the dialed number on a 7 segment display; .also using the SLIC just to provide ringing current. Now I may make a phone to phone demo board of my own! You sir, have expanded my horizon; thank you so much. Incidently in the UK we call the Central Office the Exchange. Also watching earlier " episodes" it struck me that perhaps you could hive off the service signal generation to another processor and just call the tones as required...
I’m currently ordering more parts to try some more things out including making a sort of expansion switching matrix where a bunch of exchanges can all plug-in and it will have its own way of routing calls between several different nodes, so there could be multiple separate calls in place or even party lines with more than two on the same circuit. I’ve been working on it more than five years at this point so the ideas keep coming.
The stand works if you place the groove on the iron just above the nut onto the notch in the stand plate.
Thanks for this video, it was helpful and cleared up some confusion about how to import symbol parameters into a file!
Awesome information and video.
Isn't the second circuit, the band amplifying filter, just an oscillator? How do you stop it from doing that? The Twin T has a 180 deg phase shift, the op-amp inverts the signal, another 180 deg and it has plenty of gain. 2 pi around the loop and gain >1.
In a more complete implementation of that circuit as a filter there's another feedback path added. In this video I used it as a Wah filter effect and then modified it to force oscillations (first step toward drum synth) kzread.info/dash/bejne/pWqJltaHj73YcpM.html
hello friend , thanks for the quality video . I'm trying to simulate an electret mic + its noise and i wanna add this noise to the simulation by injecting the noise spectral density into a noise generator ! is there a way to do that ?
Hello. My soldering station 8898 no longer displays the soldering iron temperature display correctly. The lower limit is 356. The upper limit is 932. Although it should be from 180 to 500. When turned on, it shows not 352 degrees, but 662. The soldering iron itself works. The hair dryer display shows the temperature correctly. Can you tell me what elements might have broken? What should I check?
These SLICS would have depended on a codec's bandpass filter to filter out things outside of the voice band, as SLICS would have typically been connected to to a codec/filter and then to a TDM PCM highway for digital switching. If you are going to directly connect one of these to another SLIC, then external filtering would be required. As far muting the output during ringing, couldn't that be done by using a crosspoint switch matrix (e.g. MT8816) to connect the audio path to other SLICS and to the ESP32? The only thing which could be an issue is the spikes coupling through the crosspoint switch during ringing due to their fast rise times, but might be able to be solved with an RC snubber at the output of the bandpass filter.
I'm looking forward to you completing this project.
There may be big progress sometime this weekend if no big problems show up.
Can both soldering iron and hot air be used actively at the same time? Is the insulate wire high heat tolerance? if I accidentally touch the soldering iron on it, will it melt?
I always use the iron and hot air at the same time for example if I just made a solder connection and I have heat shrink tubing, I put the tubing in position after and just pick up the hot air tool and shrink that and then go back to soldering with everything active. another thing I sometimes have to do is make some through hole solder connections on a breakout board and then there’s a small surface mount part as well so I pick up the hot air tool and heat that up and then just go back to the soldering iron. I don’t know if the wire jacket is heat resistant, I’d rather only find out by accident instead of testing it out and finding its vulnerable but I’ve had it almost 3 years and I haven’t had an incident
Thanks for all of your hard work on this! I think I might build a couple of boards of your design to use as a starting point for a slightly different take. It seems that each node could support more than one phone line, more like a central office. Another idea is using a RJ45 interconnect between nodes. The four pairs of wires in the RJ45 (ethernet cable) would be enough for the RS-485 control link as well as two phones (if someone did not want to use WiFi for the control link) or 4 phones plus WiFi for control link. Of course, as you say the WiFi also provides the possibility of 'wireless' nodes. Good work!
I am working on an idea to make an expansion board where each node can have its RJ 11 cable going to a matrix board with at least four channels so then that can become more of the central office controlling who gets routed to which node so I’m going to be experimenting over the next couple of months with that.
ctrl+ right click on the component to gain access to the Component Attribute Editor FYI
thanks bro
Hello friend, I am investigating the ripple noise from the output of car alternators, especially 12 and 24 volt alternators, I have seen some videos of what the outputs of these alternators are like and I wanted to see if I can simulate them. with LtSpice, and with your video I have come to the conclusion that I can. Your video has been very helpful to me, that's why you earned my subscription and hands up. Greetings from my beautiful Venezuela.
Beautiful :)
Jenny!
she’s back, and she’ll be making a few more appearances.