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41
It would seem simplest to use a parabolic reflector dish instead.
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Google PICPET.  This is a family of dirt cheap time stamping interval counter chips.  Each pulse in is time stamped and sent out a serial port (sub microsecond resolution).  It can handle inputs up to 100 Hz, so you will probably need a divider on the input... maybe one of his PICDIV chips will be suitable.
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I'm looking for an AC/DC power supply that offers synchronization to an external frequency source. This seems like an option that's offered on DC/DC converter chips (eg: the LT8614 has a SYNC input). Has anyone has come across a similar option on off-line switchers? The only example I've found so far is the Artesyn iMP series. These are nice supplies, but have way too many bells and whistles and is too expensive for my application. Output voltages are 6V, 15V and -15V, current draws of a few amps per rail. Thanks.
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Buy/Sell/Wanted / Re: [FS EU] 100nF 0603 caps, reels of 4000 units
« Last post by MasterTech on Today at 04:38:04 pm »
Don't get me wrong, I think that's a reasonable price with current MLCC shortage. They may solder just as well as fresh parts, or may not.

I'm getting you exactly right. These capacitors are in perfect condition, otherwise I wouldn't sell them, but I guess you would and there lies the doubt. I measured 20 of these and they measure from 97.5 to 101nF, most around 99, and this is X7R so any lower capacitance could be explained by applied voltage. Can't reflow them right now but I'd bet they'd be perfect, the capacitance itself tells they have been stored properly, besides that I know that for a fact. Anyway end of story
45
Test Equipment / Re: Spectrum Analyzers: Old Big Iron or New from China?
« Last post by 0culus on Today at 04:34:00 pm »
Thanks for the insights. So I get the impression from what you wrote that going for 22 GHz isn't going to be worthwhile unless I'm also getting one of the huge 2 part HP boat anchors anyway? Are there any specific SAs that meet the criteria you mention, including phase noise? That isn't mentioned in the buyers guide.

Not specifically in regards to the boat anchors, but just generally.  The price scales up pretty significantly with bandwidth and with product generation, so if you don't need those top 10-15GHz, going with the lower bandwidth option will probably get you a product generation or better more advanced of an instrument which will mean lower noise, probably higher sweep speed, and more features, so if you don't have a direct need for the bandwidth, you can save a bit or get some other performance and quality of life benefits instead.  Nearly every newer generation of SAs by the same company is going to have somewhat better performance across the board, and is more likely to have nice UI enhancements, connectivity options, or extra analysis features.


For phase noise, generally finding something with an upgraded oscillator will almost always be better than the base version, but if you look through the datasheet and find a phase noise analysis software option, then the rest of the system's hardware is already designed around being able to measure those aspects.  You also very rarely find it on instruments without 10Hz RBW or lower - the small fluctuations just don't show up that well with a 100Hz RBW.  But in mentioning it, don't forget to figure what options it comes with into what you're considering - sometimes you can still buy upgrades, but they will be expensive, so if you find a unit that has some extra options enabled that look interesting, it could be worth some premium over a regular unit since it's otherwise difficult to get them.

Awesome, thanks again for your feedback. This has been a huge help! I'm going to keep shopping around for a while till I become very familiar with what's out there...and who knows? Could find a good deal. :)
46
Microcontrollers & FPGAs / Re: i.MX RT 600
« Last post by Berni on Today at 04:32:04 pm »
The problem with XMOS is that its hard to find suitable applications for it. They market them as being 32 core microcontrollers but its actually a 4 core microcontroller with 8 threads on each core (And you need to use at least 4 threads per core to get the full MIPS speed on that core). Additionally each core lives in its own memory space with its 256KB of RAM (This used to be only 64K). That sounds like a decent amount of on chip memory right? Well... there is no flash so this RAM has to hold all of your program code too, and there are no external memory interfaces so expanding this memory is not possible. The impressive MIPS number and single cycle execution does give it significantly more processing grunt than ARM MCUs, but there is no hardware floating point and because you have no peripherals you often have to dedicate cores for bitbanging (using serdes on pins) of things like UART, SPI, I2S etc so a few 100s of MIPS will be lost to IO tasks.

So in the end the XMOS chip is in an awkward position standing on the border where the lands of MCUs, DSPs and FPGAs intersect. Its a fast MCU with limited memory size, its a DSP with no float and a not hugely impressive MMACs spec, its a FPGA that can run weird exotic interfaces but only at speeds under about 50MHz and limited complexity. XMOS has a lot of cool things that nobody else does, but ends up being limiting in annoying ways.

So for most applications in think the RT600 makes more sense.
47
General Chat / Re: No more free shipping from China to USA?
« Last post by station240 on Today at 04:30:44 pm »
Not a bad thing. Keep in mind that under UPU rules, when China ships things to US, China only pays the part to get the goods shipped to US boarder. US pays the distribution fee, which is very expensive due to labor cost. As a result, USPS is subsidizing this fee.

Under this rule, the more a country ships, the less a country receives, the more it takes advantage of UPU rule.

Since USPS has to absorb the cost, that means you pay more to USPS when you ship anything abroad.

Last time I shipped something from US to China, it costed me $13.75 for a bloody piece of paper.

To me, this is a good move. I live in US, I ship to China and many other places outside US, and I don't buy much from China without an US stock.

The subsidized chinese postage only applies to certain products and sellers, the average person on the street in china still has to pay the full normal postage costs.
For international courier services, this is much the same as we pay in the west.

In Australia the postal service has jacked up the prices for all parcels, not just international ones.
So the result of chinese free postage, is I pay more to post something within Australia.This makes selling or even giving stuff away un-viable at times.
48
Metrology / Re: LT3094 -ve LDO equiv to LT3045
« Last post by TiN on Today at 04:26:23 pm »
I got few some weeks ago from Digikey, but they still sit in ESD bag :)
49
EEVblab / Re: eevBLAB #55 - Solidworks Pricing is BULLSHIT
« Last post by Barny on Today at 04:17:42 pm »
I'm working wirh NX from Simens.
Its not exaktly ceap but I am not aware of price fixing.

Cars in the other hand are massive price fixed.
Here in Austria its sometims massive cheaper to get the car delivered over thousands of km than bying the car local.
And even fuel is massive price fixed. The price diferences are enorm even inside the country.
If you drive 30 to 40km, the petrol stations have complete different priceing.
50
Metrology / Re: LT3094 -ve LDO equiv to LT3045
« Last post by MiDi on Today at 04:16:51 pm »
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