measuring nanoamps with lots of noise

Started by Anonymous in sci.electronics.design6 years ago 30 replies

I am having a difficult problem on a current project so I was wondering if anyone could help. This is a project where I have to measure current...

I am having a difficult problem on a current project so I was wondering if anyone could help. This is a project where I have to measure current generated by a sample at high temperature inside a furnace. The current is in the picoamp-nanoamp range depending on temperature and I have been using a Keithley picoammeter. The furnace is controlled by a PID temp controller connected to


DIGITALY CONTROLLED RADIO RECEIVER

Started by RealInfo in sci.electronics.design9 years ago 5 replies

Hi all My question is about the structure of a digitally controlled radio like this http://www.hamradio.com/detail.cfm?pid=H0-010818 From...

Hi all My question is about the structure of a digitally controlled radio like this http://www.hamradio.com/detail.cfm?pid=H0-010818 From the point of view of the micro controller that controls it . If I understand well that micro does 3 main things 1> controls the frequency of the PLL that functions as a local oscillator used by the rf mixer 2> sends the relevant data to the


Request help sizing a cartridge heater.

Started by mpm in sci.electronics.design4 years ago 4 replies
PID

I want to build a plastic clamshell heat sealer, for volume production use. I have a hand-sealer, but it is too slow and you have to make several...

I want to build a plastic clamshell heat sealer, for volume production use. I have a hand-sealer, but it is too slow and you have to make several welds to adequately seal the clamshell we are using. I intend to use a PID controller (as a thermostat) and two cartridge heaters. I'm going to machine a steel block, to fit where it needs to over the clamshell seal points, and be drilled to accept ...


Video: What is a PID Controller?

Started by Tim Wescott in sci.electronics.design6 years ago 34 replies
PID

Just posted a video. It's my first real effort and, as videos go, rough as a cob -- but I think the information is solid. I have a 15-minute...

Just posted a video. It's my first real effort and, as videos go, rough as a cob -- but I think the information is solid. I have a 15-minute time limit -- trying to fit an informative video into that is kind of like explaining General Relativity with a book of haiku. https://www.youtube.com/watch?v=2elEXcv0AV8 YouTube time limit complex subject, 15 minutes very hard. -- Tim ...


model for BLDC motor control with PWM

Started by alb in sci.electronics.design7 years ago 4 replies

Hi everyone, I've an half H-bridge motor driver controlled via a PWM. We read current on the phase terminal and regulate the PWM accordingly...

Hi everyone, I've an half H-bridge motor driver controlled via a PWM. We read current on the phase terminal and regulate the PWM accordingly through a PID. The exercise is to play with all parameters (transfer function, sampling frequency, adc resolution, pwm resolution) in order to get the right precision on the output. I wanted to model the loop with something like MATLAB or Octav...


Foundation Fieldbus Microcontrollers

Started by Anand P. Paralkar in sci.electronics.design10 years ago 2 replies
PID

Hi Everybody, I am trying to build a positioner with Foundation Fieldbus support. The system architecture would consist of: a. Analog In...

Hi Everybody, I am trying to build a positioner with Foundation Fieldbus support. The system architecture would consist of: a. Analog In (4 - 20 mA for position set-point input in manual mode). b. Analog Out (4 - 20 mA position output to the pneumatic block). c. Microcontroller to implement the PID control loop with support for Foundation Fieldbus. (The primary role of the Foun...


Accuracy of resolver required for PMAC motor computation

Started by mook johnson in sci.electronics.design8 years ago 6 replies

Most of the motors we deal with have motor full blown resolvers for motor commutation. The design engineers are wringing their hands about...

Most of the motors we deal with have motor full blown resolvers for motor commutation. The design engineers are wringing their hands about the required resolution for the R2D conversion. I know it doesn't require 16 bit resolution but how low can you go. Assume 10,000 RPM with a 10KHz PWM and sample rate. This will be FOC controlled with a inner PID phase current loop and external PI...


Hot air soldering station recommendation

Started by Klaus Kragelund in sci.electronics.design2 years ago 9 replies

Hi I am trying to get my lab up to speed, so now I need a hot air soldering station Seen this...

Hi I am trying to get my lab up to speed, so now I need a hot air soldering station Seen this one: https://m.aliexpress.com/item/33034086674.html?pid=808_0000_0131&spm=a2g0n.search-amp.list.33034 086674&aff_trace_key=&aff_platform=msite&m_page_id=822amp-QKibdmRAN4hCllCLcM0CAA1580243088270&br owser_id=b1e4e133b2d5400298ff0d819e9ba525&is_c=Y&gclid=null Cheap, but any good? Other recomme


LTC6992 TimerBlox, jitter at low duty cycles

Started by Joerg in sci.electronics.design7 years ago 6 replies

Folks, Got an LTC6992 in the -3 version which goes from 0% to 95% duty cycle, controlling a fairly massive PWM stage. It lives inside a...

Folks, Got an LTC6992 in the -3 version which goes from 0% to 95% duty cycle, controlling a fairly massive PWM stage. It lives inside a (stable) PID loop and works ok except at very low duty cycles under 2%. There is breaks into a jitter and because I am driving big capacitive loads that results in tons of wasted power. Also, it quite abruptly turns off at a fraction of a percent inst...


Temp Controller RNR, SNR what do they mean?

Started by Dave, I can't do that in sci.electronics.design7 years ago 9 replies
PID

Hi All, I am wanting to build a small 110vac temp controller for sous vide cooking. Found a bunch of PID controllers for around 20-bucks and...

Hi All, I am wanting to build a small 110vac temp controller for sous vide cooking. Found a bunch of PID controllers for around 20-bucks and lots of how-to-build instructions. RNR, SNR and SSR? I am guessing SSR is Solid Sate Relay, but what are SNR and RNR? Search as I might I cannot find an explanation for those two. I see a zillion ads offering either type but have no idea which one...


Adapting a Garmin Traffic Receiver to car antenna?

Started by DaveC in sci.electronics.design12 years ago 33 replies

Garmin makes an "integrated" FM traffic info receiver for some models of GPS that allows connection to the car's AM/FM antenna. But not my model...

Garmin makes an "integrated" FM traffic info receiver for some models of GPS that allows connection to the car's AM/FM antenna. But not my model (Nuvi 660); I must use only the GTM20, a cigarette-lighter-powered model: Benefits of using the car's antenna are mostly stealth: the cord-that-is-the-antenna between the cigarette lighter (which w


A bit OT: 4k ultra HD DTV test transmissions started in Europe

Started by Jan Panteltje in sci.electronics.design9 years ago 5 replies
PID

4k ultra HD DTV test satellite transmissions started in Europe http://www.eutelsat.com/products/broadcast-ultra-hd.html The picture is...

4k ultra HD DTV test satellite transmissions started in Europe http://www.eutelsat.com/products/broadcast-ultra-hd.html The picture is transmitted as 4 HD segments, top left, top right, bottom left, bottom right, each on its own PID. I have received the stream, decoded it, displayed it, now I need 4 seemless HD monitors. See my postings in alt.satellite.tv.europe.