Search found 63 matches

by dschlic1
Wed Jul 18, 2018 10:05 am
Forum: Projects
Topic: IoT Router
Replies: 0
Views: 383

IoT Router

I now have 6 IoT devices on my home network. This network is fed from the FIOS ISP router which probably has not been updated in years. So I am looking into purchasing a new router. I want some level of protection for the IoT devices, most of which will not get updated. In doing some research there ...
by dschlic1
Wed Jan 10, 2018 12:29 pm
Forum: PCB Design Questions
Topic: Which PCB layout software should I use?
Replies: 6
Views: 990

Re: Which PCB layout software should I use?

If you are running Linux, there is an excellent program called "PCB". There is also a design suite called gEDA.
by dschlic1
Fri Sep 29, 2017 10:21 am
Forum: SparkFun Product Questions
Topic: RS232 Shifter - does it drive negative voltage?
Replies: 2
Views: 304

Re: RS232 Shifter - does it drive negative voltage?

Just looked at the schematic, and no it will not.
by dschlic1
Fri Apr 07, 2017 11:01 am
Forum: SparkFun Product Questions
Topic: PH Meter
Replies: 2
Views: 494

Re: PH Meter

pH is only defined in water.
by dschlic1
Mon May 16, 2016 10:32 am
Forum: Projects
Topic: Alternative connector to RJ45 Jack for Ethernet
Replies: 4
Views: 971

Re: Alternative connector to RJ45 Jack for Ethernet

You have to be careful here. There needs to be a magnetic transformer between the cable and the actual Ethernet IC. In some cases this transformer is located in the jack. You can get separately mounted transformers.
by dschlic1
Wed Dec 23, 2015 9:56 am
Forum: Everything ARM and LPC
Topic: ADC internal resistance
Replies: 2
Views: 1573

Re: ADC internal resistance

Most ADCs have a dynamic input impedance: They charge a capacitor in a sample and hold function. Better place an op-amp buffer between the divider and the ADC input.
by dschlic1
Wed Jul 08, 2015 10:33 am
Forum: Projects
Topic: Measuring low frequency vibrations
Replies: 4
Views: 428

Re: Measuring low frequency vibrations

Please note that for most humans hearing goes down to at least 10 to 20 Hz. 60 Hz is the hum you hear (at least in the US) from some electrical equipment. Also while most microphone specs show a lower limit at 100 Hz they have usable repeatable response much lower with a loss of accuracy but not rep...
by dschlic1
Mon Jun 29, 2015 10:24 am
Forum: Projects
Topic: Problem with cheap (HC-SR04) Ultrasonic Rangefinders
Replies: 9
Views: 4663

Re: Problem with cheap (HC-SR04) Ultrasonic Rangefinders

A potential workaround to this issue is in your "master" processor if the echo remains high after a certain period of time, assume loss of echo. Trigger the unit again after that and continue on. When an object comes into range the echo output will go low and you know that you have a return echo.
by dschlic1
Fri May 15, 2015 11:41 am
Forum: PCB Design Questions
Topic: A newbies attempt to control a bunch of peristaltic pumps
Replies: 2
Views: 1373

Re: A newbies attempt to control a bunch of peristaltic pump

You might look at the following for the RaspberryPi:
https://www.sparkfun.com/products/11561

No need for a custom board, just add four of them and you have your drivers.
by dschlic1
Wed Feb 25, 2015 11:39 am
Forum: Everything ARM and LPC
Topic: IDE for STM32
Replies: 4
Views: 2410

Re: IDE for STM32

I have used the free version of Atollic TrueStudio. I also used FreeRTOS in TrueStudio. I don't know how well the latest versions work.
by dschlic1
Tue Aug 26, 2014 10:07 am
Forum: Projects
Topic: Zener divider network
Replies: 18
Views: 2046

Re: Zener divider network

I would look at using some kind of series pass regulator (IC) to drop the battery voltage down to 6 or seven volts for the ProMicro. As for the ADV vref, you want the most accurate, stable voltage you can get. I would use a reference voltage source for that. All told it would increase the cost sligh...
by dschlic1
Thu Aug 21, 2014 11:13 am
Forum: Projects
Topic: How to Simulate Differential Pressure Sensor?
Replies: 23
Views: 2681

Re: How to Simulate Differential Pressure Sensor?

One method is to use two pressure sensors, one on each side. However you can run inot resolution/accuracy issues if the common mode pressure is very high and the pressure difference is very small. Also will need two ADC point for each DPIT.
by dschlic1
Thu Aug 21, 2014 11:08 am
Forum: Projects
Topic: UV Sensor Project
Replies: 4
Views: 456

Re: UV Sensor Project

Have you added the decoupling capacitors as called for in the data sheet? Also what range of output voltage are you working with? If the range is limited (spec sheet calls for 1 to 3 volts) perhaps some signal conditioning to change the range to cover more of what your ADC uses. Another way to incre...
by dschlic1
Wed Aug 20, 2014 12:00 pm
Forum: Projects
Topic: Direct Burial speaker wire suitable for 12V 5A power?
Replies: 5
Views: 950

Re: Direct Burial speaker wire suitable for 12V 5A power?

Three conductor romex actually has four conductors.
by dschlic1
Fri Sep 27, 2013 9:55 am
Forum: SparkFun Product Questions
Topic: if there's one thing that's always missing, it's insulation.
Replies: 10
Views: 2446

Re: if there's one thing that's always missing, it's insulat

You can also purchase insulated tubing. Checkout Digikey.