Recent Posts

1

Test Equipment / Re: Enabling options on Agilent ESA series E4402B E4404B E4405B E4407B

« Last post by Larry_Bridge on Today at 03:30:31 pm »

Thank you very much.
I will check and let you know.

2

Beginners / Re: How Current Limitation is happening in the circuit???

« Last post by ommsiva on Today at 03:29:16 pm »

Mam,

Sorry,   absolutely you are correct.  It's my mistake.
I have disconnected power transistor from heat sink out of frustration.

3

Projects, Designs, and Technical Stuff / Re: a high side load switch made from n channel and p channel mosfet working princip

« Last post by Doctorandus_P on Today at 03:27:41 pm »

Yes that is a possibility, myne had to work from 12V to 50V, so that made it a little more complex.

Benno

Meh, replace R2a in the previous schematic with a TVS diode, or better, add a TVS diode to limit the maximum gate voltage, but leave  the resistor so it will firmly turn the FET off when it should be off.

Circuits like this switch quite slowly, because of the combination of resistors with the gate capacitance. This is OK for switching loads occasionally (such as also done with Relays), but if you want to switch loads fast (such as with PWM) then this slow switching may cause a lot of trouble and the FET is likely to let out it's magic smoke and die in a puff or a loud bang.

4

Microcontrollers / Re: primitive serial CLI / Console for embedded systems - Ideas for implementation?

« Last post by Warhawk on Today at 03:21:58 pm »

And one extra question.
Does it make sense to optimize the CLI for VT100/Putty/miniterm type of communication (each character transmits immediately after the keypress) or for terminals that "wait for enter" (e.g. Termite) and send the whole line?

5

Microcontrollers / Re: primitive serial CLI / Console for embedded systems - Ideas for implementation?

« Last post by nctnico on Today at 03:21:30 pm »

Unfortunately no code to share. But what you need is a function which replaces spaces by 0x0 and puts a pointer to the beginning of each parameter in an array and keep track of the number of parameters found. Then a for loop which iterates through the list with commands and comparing each command to the first element of the parameter found.

6

Test Equipment / Re: Enabling options on Agilent ESA series E4402B E4404B E4405B E4407B

« Last post by PA0PBZ on Today at 03:21:23 pm »

2 Forum posts and a PM, I guess you are in a hurry? 
Well ok, check your PM.

7

Test Equipment / Re: Firmware update 1.23 - GW Instek GPP-4323

« Last post by Hexley on Today at 03:18:33 pm »

Firmware 1.23 is available since few days.

Found a bug in FW_GPP-X323_V1_23 firmware for the GPP-4323 which I downloaded and installed today.

Sequence to reproduce:
SYSTEM
VERSION, then RETURN
VERSION, then RETURN (repeat for a second time)
RETURN

The system now becomes totally unresponsive. No buttons work. The beeper emits a continuous sound. The GPP-4323 must be powered off and back on to recover.

This has been reported to Instek.

8

Other Equipment & Products / Re: Lets see your Nixie Tube equipment

« Last post by Dave Wise on Today at 03:13:57 pm »

One of my HP 740B DC Voltage Standard/Differential Voltmeters.  On its side for troubleshooting.  The Nixie tubes display the knob positions, they don't dynamically change with input voltage.  So just an electronic version of the mechanical digit wheels on a Fluke differential voltmeter.

9

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

« Last post by KungFuJosh on Today at 03:12:02 pm »

Difference is that "the other" scope actually does work as 4ch 200MHz BW scope.
At all times, no special conditions..

Exactly. My comparison was fair, and compared them as 4 channel scopes with what their sampling rates actually allow.

The argument that it's not that hard to disable 3 of the channels on the Rigol to get higher bandwidth is comical, not professional.

one would expect the Siglent to cost ~10X......yes it's that good!! Heck one would expect the Rigol to cost ~3X also!!!

I think that's a great comparison. Both scopes are great at what they do, and cost about the same, but the Siglent is worth 10x what it costs, and the Rigol only 3x what it costs. It's a great value either way, but one is clearly superior...if you want to use it as a tool to do work. If you want to hack and tinker with a the scope as a toy, then YMMV.

10

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

« Last post by tooki on Today at 03:11:15 pm »

As a complete aside: most 120V, 50-60Hz power supplies will also work fine on the 115V*, 400Hz power used on aircraft systems. But most are not certified for it, or only mention it in footnotes.

*And yes, this is 115V nominal, not 120V!