Recent Posts

1

Microcontrollers / Re: Has anyone used ASAN & MSAN, and relevance to embedded arm32

« Last post by ataradov on Today at 04:06:07 pm »

I don't think those would be very useful on embedded code. Asan adds instrumentation in the code and then replaces low level malloc() and free() calls with custom tracing versions.

This typically increases code size by 2-3 times, decreases execution speed by the same 2-3 times. And it also needs a lot more RAM to store all those allocation records. On embedded with custom allocators, you will essentially get one or no real malloc() calls, so the tool will be useless.

In theory, it might be possible to work with the instrumented code and match it with the custom allocators, but I'm not aware of anyone doing it.

2

Beginners / Re: uCurrent Gold Schematic

« Last post by uf29857 on Today at 04:05:30 pm »

Thanks for the feedback. Will the circuit work as intended?

3

Other Equipment & Products / Re: Any opinions on the Aixun T420D?

« Last post by Astray on Today at 04:02:53 pm »

Yes, T115A handle with modified plug (with added "stanby" pin #4 and wire soldered to it) is connected directly to the host. Other end of the added wire must be connected to mast with bracket for T115A handle.
Yellow pair must be disconnected from mast's nut because this pair is "standby" pin signal of cradle's plug that also connected with T245/210 bracket and work with other channel (T245A handle in my case).
Sorry for my English, I can't explain it in any more detail or more clearly. 
....
There is another way to get "donor's" pin without buying donor handle or plug. You can extract pin #3 (extractor) from plug of holder. But in this case you have to connect extractor in parallel with bracket so that the station goes into standby when you change the 245/210 tip.
But buying a donor T245 handle is more reasonable, since this handle does not lose its functionality after removing the unused pin #6 and can be useful at any time if the genuine AiXun T245A handle breaks.

Do you have a photo or diagram of how the wire to the tall stand is connected to the main station? Is that standby pin just a ground pin or something different?

Wondering if might not be possible to internally connect the standby pins of both channels inside the main station so there's no need to run an extra wire.

Does anyone else know how these soldering stations work to put irons into sleep mode?

T420 in the T245A configuration (with T245A handle included, but without specific mast with hangle bracket for T115A handle) have a regular price for $181.48 at this store. I used a $20 coupon at "anniversary sale". But similar coupones or promocodes you can get it very often. Aliexpress holds different sales almost every month.

The T115A handle i bought at the China DIYPHONE Store aslo with coins. Regular price was $8.19.

Additional cheapest T245 handle I bought for $3.03 with coins just to have a "donor's pin".

Your prices are just across the board cheaper than mine, I believe it has to do with location as they probably have shipping costs included in the total price of the device. I shopped around quite a bit to find the cheapest I could and $210 was the cheapest before any coupons.

In hindsight, the cheapest maneuver was probably buying a T405 unit and hoping to get sent one with T420D firmware and buy the 245 handle. I think this would be the most cost effective as I've seen the 405 go for $170 before coupons and it would also include the little arm stand and you wouldn't need to buy those separately. Still a gamble though because no way to know if you'll get a main unit with T420D firmware.

4

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.

5

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...

6

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.

7

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.

8

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.

9

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?"

10

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.