Recent Posts

1

Beginners / Requesting i2c program for lpc11e36 microcontroller

« Last post by kamalesh@oppila.in on Today at 09:17:44 am »

Hello,

I am new to this field. Actually, We are started working with lpc11e36 micrcontrollers.

We successfully able to do the uart interface program with this microcontroller. But, for testing purpose, we have to do i2c program.

I searched in many places and finally written one program for i2c.

Now, After initializing the i2c, I checked with scope, there is no scl signal in scope. Program also stucked inbetween the progress and it is going to the event of i2c_wait.(particulary i2c_chipMasterSend function strucked).

How to clear this error?
Is there any other examples to move forward?

Regards,
Kamal

2

RF, Microwave, Ham Radio / Re: Problem with Inductor Self Resonant Frequency

« Last post by wilhe_jo on Today at 09:16:47 am »

automotive standards

Well, that's one reason, but I doubt it...

On the other side, the main difference seems to be the lower usable frequency limit (8kHz for 50uH, 70kHz for 5uH). I cover the low frequencies with a current probe.   

Well, no. You change the impedance presented to the EUT pretty drastically.

If you want/ need to go below 150k, you need the 250uH inductor as well.
This will also attenuate noise on the grid. You correctly found that an insulation transformer is needed to get rid of the leakage. But it will also remove low frequency noise.

In my lab, I use 90% of the time an audio amp to make some clean mains. However, sometimes I use the real one and I'm always surprised how dirty it is. The 40dB+ attenuation from the Lisn is really key in these situations...

If you just want to have "some" results, you could just multiply the current with the LISN impedance and you get something similar.

For everything but mains,  just take some capacitor and 100R in series to some 50R input.
If you have more than 1 conductor (more than just some cable shield), just take N times the R/C values for each conductor.
That'll simulate a CDN. But here you also loose the defined impedance....

Yes, you can do pre-compliance without well defined impedances, but you'll never be sure that you're fixing an actual problem.

73

3

Projects, Designs, and Technical Stuff / Re: I made a 50 ohm load with BNC connector, Is this correct?

« Last post by MarkT on Today at 09:06:48 am »

Too much choice for the electrons, they got confused (!!)

4

Beginners / Re: what an oscilloscope recommended for a woman passionate about electronics?

« Last post by gnif on Today at 09:06:46 am »

@BTO, that was completely uncalled for. take a 7 day timeout and calm down.

5

Projects, Designs, and Technical Stuff / Re: How to run some I2C sensors outdoors over longer distances (5-10m)?

« Last post by MarkT on Today at 09:03:48 am »

I'm tempted to mention MBUS here, although its not completely appropriate, it was designed to network 100's of units over km sized areas with 2 wires and provide power too.  It uses 36V signalling host->sensor and current-mode signalling sensor->host, making it very robust w.r.t. noise.  M stands for meter, and its primarily used for utility meters over large sites, but supports sensors and so forth too.  The 2-wire interface is polarity agnostic so any old person can wire and not get it wrong!

6

Beginners / Re: what an oscilloscope recommended for a woman passionate about electronics?

« Last post by tautech on Today at 09:02:39 am »

............

And if you had bothered to read a bit further you would know she already bought a Siglent scope and is happily playing with it.

Instead he quotes the OP in a 4yr old thread.   

7

Beginners / Re: what an oscilloscope recommended for a woman passionate about electronics?

« Last post by pcprogrammer on Today at 09:02:22 am »

Just to prevent it from being deleted. 

Hello, I'm Charlotte and I live in Switzerland 
I work in the hospital, but my hobby is electronics; i try to repair electrical devices, 99% of the time I don't solve the problem, but that's okay
 
Women usually read gossip magazines 
but there are women who prefer to make love with electrons 
My equipment is: soldering station, two multimeters, bench power supply.
I'd like to start a seductive relationship with an oscilloscope..   
I don't want to spend too much, but I don't want to buy the worst...
For example the model Rigol ds1052E is ok for beginner woman? or better Rigol ds1202z-e (200mhz) ?
Other brands on these prices?
Do you have any advice for me? i am in your hands...
thanks
Charlotte
 

OK, so.. Welcome to Electronics.

Now i don't know how being a woman has anything to do with having an Oscilloscope unless you wanted to get it in Pink
with a rainbow unicorn cover.

so you see this...

Women usually read gossip magazines 

IRRELEVANT

but there are women who prefer to make love with electrons 

and there are women who watch the BOZONE AND THE BEAUTIFUL
...IRRELEVANT

I'd like to start a seductive relationship with an oscilloscope..   

IRRELEVANT....... Also goes with saying

For example the model Rigol ds1052E is ok for beginner woman?

so... How many more times are you going to keep saying You're a women ?
We got it, Your name is Charlotte and we made the logical conclusion that you're a women

Do you have any advice for me? i am in your hands...

1. Stop mentioning over and over that you're a women, it's of no consequence

2.

My equipment is: soldering station, two multimeters, bench power supply.

Try mentioning specs and model numbers so we know what you have, as we woudl already logically conclude that you have these things
in some shape or form

3.

I work in the hospital, but my hobby is electronics; i try to repair electrical devices, 99% of the time I don't solve the problem, but that's okay

IF YOU LIKE WE CAN JUMP ON A ZOOM CHAT OR SOMETHING and i can help you get that 99% not solving the problem to more like
5% NOT solving
if 99% of the time you are NOT solving the issue , then.. you need some guidance

for me it's more like 98% of the time I AM solving it.

4.  OK, so your entire comment is basically

I don't want to spend too much, but I don't want to buy the worst...
For example the model Rigol ds1052E is ok for beginner

Classic beginner question...
- First you're confused because you've put yourself in a circular argument... Cheapest possible but not shit.   that's not going to happen.

- Secondly DS1052E Should not even be a consideration.
  You can pickup a DS1054z for around $300 - $400 thus making this your first logical choice
  for around $200 - $300 you can pickup a Hantek  DSO2C15
All of these are better than getting a DS1052E
and all these  will be brand new with warranty

- What you want to remember is... You don't want to spend money and then have a scope that lags or is slow and then regret your purchase.
  so if a decent scope is not in your budget wait till you have the budget.
Fix a few things and make the money to buy the scope,  as i said, i can help you get your success rate up, of fixing things.


Basically you're looking for an entry level scope at a decent price that is a decent scope.
Your choice should be Rigol DS1054z
there you go, Now go and buy one

the decision process for this has already been discussed to the Nth degree, the specs, the bang for buck etc etc
the decision has already been made for you as to what is the best for you , Just find where you can find the cheapest 1054z
and get it.. Forget about the 1052e

8

Beginners / Re: what an oscilloscope recommended for a woman passionate about electronics?

« Last post by pcprogrammer on Today at 08:58:54 am »

............

And if you had bothered to read a bit further you would know she already bought a Siglent scope and is happily playing with it.

9

Beginners / Re: Calculating Rsense resistor value for motor driver

« Last post by Cuchi on Today at 08:58:50 am »

Hello, I am new fellow and I do not yet know how to navigate the site to ask my question
my question is other than the one discussed in this section but a knowledgeable person like you could either answer the question or tell me in which section to ask it in the forum and how to proceed
Ma question is as follow:
I purchased a controller as specified below

a PWM type single channel H-Bridge DC brushed motor driver for automotive use

The pin assignment is as follow: an Output high-side current monitoring function (OCM pin):+VIN; GND and M+;M-

the Microcontroller (inputs):
PWM1: Driver control signal input pin 1
PWM2: Driver control signal input pin 2
EN
GBD
+12V OUT

I plan to use it to vary the speed of a 12 volt electric motor (a motorcycle starter) connected to a 12 volt motorcycle battery as well.
The problem is that when I connect the throttle to the controller inputs (+12v pin; Gnd pin and signal pin) with the output signal of the throttle connected to the PWM1 input of the controller I obtain an inverted effect, i.e. the motor spins when the throttle is closed and at rest and the engine stops when the throttle is opened with the lever pushed all the way. If I connect the throttle signal terminal to the PWM2 of the controller nothing happens

My question is how to reverse things, i.e. make the engine spins as the throttle is applied towards more gas and not the other way around.
Thanks

10

Test Equipment / HAMEG HSM1000 firmware

« Last post by harm on Today at 08:57:33 am »

I've HAMEG HMS1000 (1.6GHz) spectrum analyzer with firmware 2.117.
I tried Rohde and Schwarz HMS-X latest firmware 2.250 with no luck.

My SA needs HMS3000.HFU file for update, renaming the RS HMS-X.hfu (2.250) did not work.
I could update the Help with renamed RS HMS-X.hmg (2.250) file but now my HELP in the SA is lost "No help available!".

Hope to find the original HMS1000 or HMS3000 firmware files.

Any help?

thanks, Harm