Recent Posts

1

Test Equipment / Re: New 2ch pocket DSO+SG - Zeeweii DSO2512G

« Last post by Sham73 on Today at 03:55:35 pm »

That's OK, just don't overdo the calibration, it won't be like a multimeter.

For calibration, I need a more or less accurate laboratory power supply and a functional signal generator, which I don’t have.

2

Thermal Imaging / Re: Flir E75 activation serial number and warranty

« Last post by _Wim_ on Today at 03:54:07 pm »

Could be the previous owner never registered it online, so FLIR thinks you just bought this brand new. Not sure however what would happen if you need the actual warrantee, could be they then need the purchase invoice also...

3

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

« Last post by Fungus on Today at 03:52:26 pm »

iircsomeone stated dho800 only works on specific brand. i have few wifi adapter here, maybe later i will try. but still, its a few more steps to do... rather than plugin usb stick and hit capture button. ymmv.

It's literally the most common chipset/brand.

I never take the WiFi dongle out. Apart from the web interface you can save all screen captures, data dumps, etc., to the internal memory and accessed via ftp as if they were local files on my PC.

You also get correct date/time stamps on the files if it's connected to WiFi.

4

RF, Microwave, Ham Radio / Re: High bandwidth FM signal generation

« Last post by enemra on Today at 03:51:47 pm »

Guys, thank you very much for the answers but a humble request - please do not post answers in the context of jammers or do link my previous posts like the user coppercone2 being smart. I am not working on jammer.

It is all about I want to create interference and come up with resilient communication solution for space-terrestrial based broadband communication. This involves a tiny band of frequencies over 400MHz bandwidth.

@coppercone2 (smart guy): My amplifier post was for a different frequency and does not involve FM there.

5

General Technical Chat / Re: Why Circuit Breakers DON'T Protect People (electric shocks)

« Last post by AVGresponding on Today at 03:50:07 pm »

Yeah, take that article with a pinch of salt; it's by Schneider Electric.

Better that than Hager. 

I wouldn't trust any manufacturer to not try to use the opportunity to sell you their product.

6

General Technical Chat / Re: A serious (as in not troll) requestfor help w/ultrasonic transducer

« Last post by IanB on Today at 03:46:39 pm »

There is a revelation that came to me somewhat late in life.

As a child, whenever I needed a widget for some project I might be working on, I would think "Where can I buy such a widget?" Only later, did it become apparent to me that if you need a one-off widget of a particular size and dimension, well maybe you could make it. For me, it was like, "Oh...you can make a thing? You don't always have to buy it?"

7

General Technical Chat / Re: ultra sonic transducers

« Last post by pete g on Today at 03:45:42 pm »

yes, i thought their might be a mathematical way to figure out the power needed. if, say i need to transmit a hundred feet how much power would i need? it's hard to get at the dogs as theres  thick bushes blocking the way. theres one commercial unit that says 150 feet range. true? it sounds like from what you folks say, its going to be quite difficult to do. some guys are putting the ultra sonic signal thru very powerful amps. i don't think i want to go there. the last thing i want is to hurt the dogs.

8

RF, Microwave, Ham Radio / Re: High bandwidth FM signal generation

« Last post by enemra on Today at 03:43:36 pm »

Nope. If thats the case i wouldnt come here to the forum. Moreover, I should be very strong enough to understand such stuffs if it is military.

9

RF, Microwave, Ham Radio / Re: High bandwidth FM signal generation

« Last post by mawyatt on Today at 03:43:10 pm »

Check out the DARPA program Computational Leverage Against Surveillance Systems or CLASS.

https://www.darpa.mil/program/computational-leverage-against-surveillance-systems

We developed the computational chip over a decade ago for CLASS.

Best,

10

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

« Last post by radiolistener on Today at 03:37:39 pm »

but AGAIN you missed the fact that OP clarified before your first reply that the 20A input was NOT the actual maximum input current established by some empirical means, but a mystery number from a long-gone employee.

Yes, when I posted my first message in this topic, I didn't notice that he don't have other power supplies and 20A is a mystery number.
And what? This is the reason you're attacking me? 

Sorry, but it looks very strange from my point of view.

By fully understanding the thread up to the point where you first replied, you would have already known that all of the system is powered by the two SMPSs, both of which are already universal input. So you’re suggesting doing what it already did.

And? I don't see a big problem here. It was clarified in the followed messages and we just follow forward. Isn't it? What is the reason to return back again and again?

And I don't see why it leads to such kind of aggression and attempt to shift discussion to persons instead of technical topics?

Don't you think you're fixated on some nonsense which makes no sense to devote so much time?