Recent Posts

1

Test Equipment / Re: Siglent SDS800X HD Review & Demonstration Thread

« Last post by Martin72 on Today at 08:43:41 pm »

Nice.
"Fun" fact:
The different modes (Average, Max Hold) are not available with the "normal" FFT from Lecroy.
You have to buy them with the "Spectrum Analyzer" option....

2

Test Equipment / Re: Power supply for home lab - do I really need a R&S?

« Last post by temperance on Today at 08:42:16 pm »

I'm not impressed. I'm not a fan of PSUs with coarse / fine control. A 10-turn pot doesn't cost that much.

Not to mention that power supplies with ten turn pots are rather rare.

3

Projects, Designs, and Technical Stuff / Re: role of optocoupler for biasing drain of amplifiers

« Last post by xvr on Today at 08:39:03 pm »

Steady state drain current of SIxxx is not enough (8.6A in best case). You need 14A. And Rdson is quite large. 11mOhm (vs 4 of previous version) But you can use a 2-3 pcs in parallel.

NPN BJT should be able to handle full Vdd, because at start of turn-on process Gate-Source of MOSFET can be considered as fully discharged capacitor. This capacitor plugged in series with CE junction of BJT to Vdd. So CE junction will see full Vdd voltage (voltage drop on R2 can be disregarded)

4

Metrology / Re: Is anyone into quantum technologies and quantum metrology?

« Last post by coppercone2 on Today at 08:35:17 pm »

that is nice to know I thought liquid helium was a requirement for 95% of quantum physics.

someone should make a list of quantum apparatus that can be used without LH

5

Test Equipment / Re: Siglent SDS800X HD Review & Demonstration Thread

« Last post by 2N3055 on Today at 08:24:13 pm »

Today, at work...
Lecroy Waverunner 9054(8bit), HDO6034A(12bit).
FFT with 100khz span, source Siglent SDG1062X, 50Mhz, 0dBm, 50Ohm.

Maybe we should have the last pages separated and moved to a new thread, title suggestion "FFT comparison and settings".

Sorry Martin,

just a last one. 
Similar to LeCroys: 50 MHz, 0dBm,20dB/div, 100kHz span, 83Hz RBW , FlatTop W.
200MHz BW limit on (HDO6034 is not 1GHz)
I think it looks very good. Noise floor is good 10 dB better.

6

Buy/Sell/Wanted / Re: Canceled Because Thread All Shit Up by "tggzzz"

« Last post by tggzzz on Today at 08:23:47 pm »

tggzzz doesn't appear to care, so does it really matter?

I found it to be a rather humorous read. It was a shame I missed the fireworks.

Whether or not I mind is of secondary importance. I do think the new title cheapens this forum. The original title avoids that, and to that limited extent I think it might be appropriate to revert it.

Deleting their posts is typical of such people. Missing the fireworks isn't particularly important, of course, but revising history is objectionable.

7

Microcontrollers / Re: RIP Z80

« Last post by SiliconWizard on Today at 08:22:07 pm »

A couple of rhetorical questions:

Can you fit the Z80 into a $5 (100+) FPGA?

Probably so yes. The T80 core is one of the most used for retro computing stuff, I have toyed with it a bit a few years ago, but it was on a Lattice ECP5 (which, while not expensive, isn't the cheapest FPGA around.) I don't remember how many LUTs it was taking up. But I can look it back up.

8

Test Equipment / Re: Agilent n5306a PCIe protocol analyzer

« Last post by alm on Today at 08:21:42 pm »

I know nothing about this specific hardware, but in general an FTP server is configured to use something else than c:\ as its root for security reasons (being able to download any file on the system like the password database). So what is /foo/bar via FTP might be something like c:\keysight\ftp\foo\bar on the local computer.

9

Projects, Designs, and Technical Stuff / Re: role of optocoupler for biasing drain of amplifiers

« Last post by john23 on Today at 08:16:01 pm »

Hello XVR, I have fount the si7461dp PMos shown below .
From datasheet  of CGHV1A250F figure 7 I need 14A and 45V for each transisor.
can they work together?
What source voltage to use in the diagram you reccomended?
why did you says that my NPN also needs to be 50V rating on VCE?
Thanks.
 
https://www.vishay.com/docs/72567/si7461dp.pdf
https://pdf1.alldatasheet.com/datasheet-pdf/download/1673867/WOLFSPEED/CGHV1A250F.html

10

Buy/Sell/Wanted / Re: Canceled Because Thread All Shit Up by "tggzzz"

« Last post by PlainName on Today at 08:15:51 pm »

That archived thread doesn't capture the other threads, where he was hounded by the usual suspects. What showed up here was just the culmination of that, the straw that broke things.