capacitive sense touch keying circuit for Morse code transmitters
$250-750 USD
Fullført
Lagt ut omtrent 5 år siden
$250-750 USD
Betalt ved levering
I am the owner of RadioSet-GO, a source of innovative, portable, QRP (low power) HAM radio equipment. I used to purchase capacitive touch key boards to integrate with my projects and they worked perfectly. Unfortunately, the owner of that business passed away, and I am left trying to come up with something just as good. I have attempted several circuits myself with only some success. I have a lot of insight into the subject that will help.
Here is what I need: A capacitive sense touch keying circuit for Morse code transmitters.
It needs to be small (I will make it surface-mount), operate on 12VDC, be energy efficient, and self calibrating. It will have only two inputs , one for dits and another for dahs. The input contacts are metal endcaps which mount to the outside of Pelican boxes. Touching the contacts with finger tips will switch the iambic keyer inside the radio and cause it to transmit. Touching both at once and holding will result in both switches closing and an alternating di-dah-di-dah-di-dah sequence by the internal keyer. Switching resistance must not exceed a certain value, and needs to be stable. It needs to respond to touch as instantly as possible, without false readings or 'self-keying'. It also needs to be immune to RFI and not generate noise in the receiver. The circuit will be used in a variety of RF environments with different antennas, up to 15 watts PEP.
Those are the general requirements.
The circuit that worked so well for me implemented two 12F683 IC's. I have included a circuit diagram, so if you can create a .hex file to make this exact circuit work for me, that would be ideal.
If you feel you are suited for this project, I will provide more helpful insight.
Thank you!
Hi, as you can see from my profile I am a capacitive sensing expert with more than 10 years experience doing what you require. I would actually advise using this IC:
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It can easily take two capacitive sensing inputs and then drive the two transistors in your circuit. What I can do is make a prototype here, show you the video, then send you several programmed chips + documentation for you to play around with to see if it meets your requirements.
Let me know if this plan works for you, sounds like a fun project!
Erik
$722 USD om 10 dager
5,0 (4 omtaler)
4,2
4,2
12 freelancers are bidding on average $595 USD for this job
Hello How are you? I read your project description carefully and I really want to work on this project. I am an electrical engineer who has 7+ years of experience in circuit and PCB design and embedded programming. I have used the capactive touch sensor and also have enough communication knowledge for this project.
I can make this project working and really want to work on this project.
I will deliver the following result.
- Schematic and BOM file
- SMD PCB design
- Gerber files and assembley file
We can discuss the project in detail via chat or call.
Thank you
Alexander
Hello,
I am Anthony from Sri lanka. We are a hardware designing & prototyping company.
Why you should hire me ?
- I have seven years of experience in the field and have developed many systems.
- I have state of the art testing lab and PCB fabrication workshop.
- We have DLP & FDM 3D printing,
- I have many contacts in China. I can help you with mass producing this.
Please contact me if you are interested.
Thank you
Anthony
Hi, I am Electronics Experts in Ireland, with 15+ years experience in industry.
I have worked with several US companies to develop their new products.
I am familiar with Microchip MCUs and have done several projects with them. I can help you with your project. Please start a chat for more detail. Thanks.
Hi there.I offer you the services for PIC12F683 designs, I complete the PIC jobs in MPLAB.
I am new on freelancer site, but I am designer expert with 10+ years of experience in Circuit designs, PCB designs, microcontroller development.
You can check our designs in our portfolio. If you want, I will share more designs I completed so far through interview.
So I like to discuss the job with you. Lets talk about your project through interview.
Thank you.
Hi,
I've worked with touch sensors before and can suggest a few options that would not
require using an mcu, but a simpler circuit designed for touch key sensing.
With a pcb made with the right layers design i think most rf interference can be negated.
I'm interested if it would be possible to mount a sensor pcb on the inside side of the
case behind the nut terminals.
Let me know if this sounds relevant,
The bid includes design of the required circuit and pcb layout.
Regards,
Nimrod.
Hey, I am a proficient PCB designer with more than 6 years experience in this field. I've done layout in Altium for high speed and RF circuits. Furthermore, I designed an SDR with high power transmitter and I know what I am dealing with when I'm going to use a captive touch nearby RF electronics. I can design this circuit with all the consideration for signal integrity in 2 weeks. And if needed, I can build a prototype for the demonstration of reliability.
Hey,
Your project looks really cool.
These are kind (unique) of projects I am looking work on.
Truthfully I don't have much experience with capacitive touch, but definitely can figure out how to get it done.
I do have lot experience with firmware, circuit design, PCB etc.
Please let me know if I can work on it.
Regards,
Vidit Katlana
Dear sir:
I'm specialist in high frequency circuit design. I've used several types of PIC microcontrollers to control RF equipment (frequency synthesizers, tone generators, PA controllers, etc).
The capacitive touch can be easily implemented in any PIC16 device.
Please, feel free to contact me about your projet,