Recent Posts

1

Test Equipment / Re: SDS800X HD Bug Reports + Firmware

« Last post by 2N3055 on Today at 07:47:31 pm »

Level indicator is wrong in zoom modus. It is not right in the bottom window (find the arrow).

I can confirm this one. It applies to Qualified and Delay triggers; seems to work OK with other trigger modes.
Steps to reproduce:

Trigger threshold for Qualified and Delay triggers is displayed incorrectly in Zoom mode

Test signal:
None required; leave inputs open.

Scope settings:
- Start from Default mode
- Set trigger mode "Qualified" or "Delay". Leave all other trigger settings at default values.
- Switch axis labels on -- just to visualize the problem more clearly
- Switch zoom mode on
- In the lower window, increase vertical amplification -- e.g. two steps, to 200 mV/div
- Adjust the trigger threshold via the rotary encoder, and observe the screen

Observed behavior:
- The trigger threshold is displayed as a dashed line, both in the upper and lower window.
- Its position is correct in the upper window.
- In the lower window, its position is incorrect. It ignores the different vertical scale in the lower window.

Will check .. Thanks.

2

Microcontrollers / Re: How to identify MCU by it's pinout?

« Last post by ColinB on Today at 07:44:11 pm »

It seems unlikely to me you'll find another microcontroller with the same pinout, I don't think this one is standard. But maybe there's one.

What I'd do, is use whatever MCU you want that is suitable (i.e. compatible voltage/clocking/IO features) and then either:

1. make a PCB module containing the new MCU, that fits the existing footprint, or

2. dead-bug/point to point wire the new MCU to the old footprint

3

Beginners / Re: Replacing SRAM IC with Flash

« Last post by VEGETA on Today at 07:43:09 pm »

for this IC he recommends:

https://www.lcsc.com/product-detail/SRAM_Cypress-Semicon_C466893.html

I use address 0 to 14 all the time but for a15 16 17 18 would be either 0 or 1... which gives different total address each time? 4 pins (15 to 18) would mean 4x4 = 16 banks, and the output is already 8 bits which means directly compatible.

so for example, setting all these pins to 0 would give me an address, let's call it memory card 1. setting a15 to 1 and others to 0 would give me another address called memory card 2...etc?

would the target device see it as it should be? a 32kx8 single pak for each address configuration?

i prefer doing a solution were no MCU or programming used. a simple switch is all needed but for this i would need 16 different output values... what type of affordable switch can this be?? crazy idea but i think a dip switch can work... won't be elegant tho

4

Test Equipment / Re: Choosing between entry-level 12-bit DSOs

« Last post by KungFuJosh on Today at 07:36:13 pm »

I'm using (TinySA Ultra).

The TinySA Ultra (as stated) is not the issue. I had clean signals up to 841MHz on my SDS2504X+.

5

Microcontrollers / Re: How do you search for a microcontroller ?

« Last post by ColinB on Today at 07:35:28 pm »

If you want to be successful in picking the right MCU, you probably need to think more specifically about your requirements. How do you know you need 100 MHz or 500 MHz? Because the core speed is only one factor of many.

Using smart and suitable peripherals for I/O will allow you to go much faster than simply a super high core clock.

For instance, the comments about RP2040 and its PIO system are spot on, it's a very interesting design.  Or something like STM32H7 if you need a lot of processing power or math.

Interestingly the Cortex-M0+ and Cortex-M23 are unique in that they have an optional single-cycle I/O port, which could make them faster than a big Cortex-M4/M7 if you need to do a lot of high speed GPIO through bit-banging etc.

6

Programming / Re: Linux Dependency Black Hole

« Last post by mag_therm on Today at 07:35:05 pm »

 OK.... On Fedora 37, the new version of  MCUX installer is now running though to completion (except it erases the bin after it finishes, ) leaving the problems
There are a few dependencies not found.
I have been able to clear a few, and there are about  8 or so still not found.
There are two reasons I think
   Fedora name suffix does not match
  Fedora path does not match
libncurses5, libncursesw5, dfu-util, libusb-1.0-0-dev

The problem with python3.8 was not that the libfile was" not found," it wants python3.8 to be active.
After I realized that, I was able to use pyenv to set 3.8 as system active

It is not worthwhile continuing with the dependency problems.

I am expecting the Debian installer to arrive.
If Debian does not work I will revert to Ubuntu

7

Beginners / Re: 555 driver and Transformer questions

« Last post by DanMann on Today at 07:31:44 pm »

@Andy, I was unsure if high time and low time were the vertical or horizontal stage. By duty cycle I think I now understand.

@Zero999, the transformer is a typical laminated core with one primary winding and one secondary winding, no center tap. It was designed for use with a mechanical vibrator/oscillator that was supposed to operate at 180cps (Hz). Unfortunately these over time have gotten way off with them putting out voltage spikes and frequencies much higher up to 1.2KHz.
I am not understanding push pull, I am guessing single ended.

I am still learning how to use an oscilliscope and do not know all the terms or what what I am seeing actually means, so the following I will do my best of what I think I am seeing.

attached is the schematic (555 oscillator.jpg) of what I am building, sort of. I started with another configuration which would not work with the diodes, but the signal I am getting is showing a duty cycle of 97%. I believe this is due a possible skipped cycle, meaning the signal rises, sharp and quick drop followed by a slightly higher rise.
In changing the time base on the scope the duty and frequency changes, I suspect this is due to the trigger setting?

Attached are pictures. I am not seeing how to put them inline?

8

Beginners / Re: Convert US standard 115V to International 230V

« Last post by am1 on Today at 07:29:12 pm »

Hi all, yes, those are the only PSU used in the device. However, there are several breakers used as well (listed). All are rated for more than the needed 220-240V, but would I need to replace them with double pole line-neutral breakers? System uses the following:


Circuit Breaker 2P 20A 240VAC/60DC Blk Rckr      SCHURTER   Allied Electronics   4430.2196
Circuit Breaker 1-P 4A 480Y/277VAC      ABB   SU201M-C4
Circuit Breaker 1-P 2A 480Y/277VAC      ABB   SU201M-C2
Circuit Breaker 1-P 16A 480Y/277VAC      ABB   SU201M-C16
Circuit Breaker 1-P 3A 480Y/277VAC      ABB   SU201M-K3
Circuit Breaker 1-P 15A 480Y/277VAC      ABB   SU201M-K15
Circuit Breaker 1-P 10A 480Y/277VAC      ABB   SU201M-K10[/li]

9

Repair / Re: Low Frequency Continuity Beep for Fluke 8060A

« Last post by Dave Wise on Today at 07:22:27 pm »

I just noticed that attach failed and only the pictures got uploaded.  Here comes schematic, PCB layout, program, and assembly instructions.

I figured out a trick for extending the frequency range on small PIC microcontrollers whose Numerically Controlled Oscillator has an undersize (16 bits) Increment register.  It's in the program comments but I didn't test it as I'd already cut off the programming header.  Affected parts are PIC10F320/2, 12F1501, 16F1503/7/8/9, 16F1713/6/7/8/9.

10

Test Equipment / Using SCPI with python via telnet to connect with a siglent scope

« Last post by eTobey on Today at 07:18:58 pm »

Hi,

i have made a little script to connect to the scope, and read data via SCPI. I have looked at the traffic, and i see, that there is data coming in from the SCPI command (see picture). But it is not printed. But interestingly, the welcome message got printed.

Anyone has an idea?

Code: [Select]

import telnetlib
class POP3Telnet:
    def __init__(self, host, port):
        self.tel = telnetlib.Telnet(host, port)
        #self.lese_daten()
    def close(self):
        self.tel.close()
    def lese_daten(self):
        return self.tel.read_until(b"\n", 1.0)
    def kommando(self, kom):
        self.tel.write(("{}\r\n".format(kom)).encode())
        return self.lese_daten()
       
host = "169.254.143.210"
port = 5024
user = ""
passwd = ""

pop = POP3Telnet(host, port)
#pop.kommando("USER {}".format(user))
#pop.kommando("PASS {}".format(passwd))

#
print("Lese Daten...")
print(pop.lese_daten().decode())
print(pop.lese_daten().decode())
pop.kommando(":MEAS:ADV:P2:STAT? ALL;")
print(pop.lese_daten().decode())
pop.kommando("QUIT")
print(pop.lese_daten().decode())
pop.close()
Output:

Code: [Select]

Lese Daten...
Welcome to the SCPI instrument 'Siglent SDS824X HD'

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