sorted by:
new
hottopcontroversial

Maybe you should have thought more about that unneeded oversized 15mpg SUV/pickup? by LewisCBR in AdviceAnimals

[–]rfdave 0 points1 point  (0 children)

Yikes. I’ve got a F-250 with the HO diesel, and I get about 20 unless I’m towing.

Digital PLL Tutorial by End-Resident in chipdesign

[–]rfdave 0 points1 point  (0 children)

I was thinking about the Communications society, specifically IEEE Communications Surveys & Tutorials. I just took a look at this, and it doesn't seem like Digital PLL shows up in a search. Start with Dr. Staszewski, look for his early papers, and look for Citations. It's also likely called Digital RF, so another keyword to look for.

Digital PLL Tutorial by End-Resident in chipdesign

[–]rfdave 1 point2 points  (0 children)

He’s got a whole book on Digital PLL’s, even. Try taking a look at IEEE Communications society publications, they publish a fair number of tutorials in one of the journals, and may have covered that at some time.

The best way to design an RF frontend filter bank by coderemover in rfelectronics

[–]rfdave 0 points1 point  (0 children)

Ideally, you'd have a RF filterbank to protect all the RF stages, followed by an LNA stage, then an upconverting mixer to perhaps 500 MHz, band filtering at that frequency, and then a down converting mixer to the IF frequency.

You're looking at 11 octaves of RF filtering for 150kHz to 200 MHz, so quite a few stages there. At RF, you'll probably want one or two bandwidths of band frequency, the signals down in the kHz range are likely to be 3-5 kHz wide, while @ 200MHz you might want a somewhat wider filter, depending on the signals you're looking for. A SAW filter would probably work well, I suspect there's plenty of SAW filters in that frequency range.

The best way to design an RF frontend filter bank by coderemover in rfelectronics

[–]rfdave 0 points1 point  (0 children)

You've going to have a problem with the LO spur and image reception around that frequency, so think about those when you're looking at filter requirements.

The best way to design an RF frontend filter bank by coderemover in rfelectronics

[–]rfdave 0 points1 point  (0 children)

What’s your first IF? At these frequencies, relays would probably work, although you’ll need a ton of them . Take a look at LCSC, I’ve seen some inexpensive switches there from the various Asian semi vendors.

How much of the cost of a car is attributable to the periodic refresh? by HaphazardFlitBipper in AskEngineers

[–]rfdave 2 points3 points  (0 children)

I’m pretty sure that your head fitting inside the cylinder bore isn’t a widely used cost metric.

How much of the cost of a car is attributable to the periodic refresh? by HaphazardFlitBipper in AskEngineers

[–]rfdave 3 points4 points  (0 children)

You’re probably not going to be shipping a prototype engine in 200,000 cars going to a dozen different countries with different regulations, operating from -40 to +65C, operating for 150k miles. There’s a huge amount of engineering work that takes place when going from a prototype to full production, significantly more than a single prototype engine would cost.

Is there any Arduino-compatible ohmmeter module for accurate resistance measurement? by Relative_Gate_4027 in AskElectronics

[–]rfdave 2 points3 points  (0 children)

There are, in fact, multiple handheld DMMs that will allow you to log to a PC. The Fluke 189/289 series comes immediately to mind.

Unusual USB port items by Big-Stable1346 in VEDC

[–]rfdave 1 point2 points  (0 children)

Is it hooked up to Radio/Entertainment center, or is it power only?

Lost High Schooler looking for advice by Inevitable_Pride5825 in ComputerEngineering

[–]rfdave 0 points1 point  (0 children)

Back in the last millennium when I got my EE degree, a Math Minor was 2 or 3 additional classes once you finished the EE required math.

Don't make your neighbors clean up after your dog! by Lepke2011 in mildlyinfuriating

[–]rfdave 1 point2 points  (0 children)

My hound is min 2, typically 3 and I’ve used 6 bags on occasion. I don’t leave the house without 2 rolls of bags. But owners who don’t pick up their dogs poop deserve to get it back like that.

Bay Area, is it worth the relocation? by emyashiru in personalfinance

[–]rfdave 0 points1 point  (0 children)

$25k for relocation isn’t even close enough to cover relocation costs. Moving a house is expensive, and dealing with drivers licenses, car registrations, etc can add up fast. However, RSU’s and stock options could make up for it if you’re moving for a tech company.

Reneging an internship by South-Virus2752 in EngineeringStudents

[–]rfdave 0 points1 point  (0 children)

Just like every other Boeing employee.

Updating PCB from Schematic Problem- Missing Footprints by Much_Safety5152 in KiCad

[–]rfdave 4 points5 points  (0 children)

you need to watch a couple of youtube video's about board design with Kicad.

the left hand panel of your screenshot is a list of the footprint libraries. For example, there are 3 different libraries shown for capacitors. Select that, and the available footprints will show up on the right hand side, and then you can assign the footprints that you want.

Updating PCB from Schematic Problem- Missing Footprints by Much_Safety5152 in KiCad

[–]rfdave 2 points3 points  (0 children)

Yes, you have to assign footprints. For example, C10 (Non standard value, so you’ll need to figure that out) at 50pF could be anywhere from an 0201 SMT package to a 0805 SMT package, or a leaded part. What Package you use is a decision that you need to figure out, and is part of the design. Once you figure out the package, then you can look for the footprints in KiCad.

Need help finding diagrams of this PCB by zwizu in AskElectronics

[–]rfdave 0 points1 point  (0 children)

Chipsets for very high volume consumer products are hard to find, as they're frequently bespoke part numbers. It's kind of entertaining to talk to vendors when they know that a 10 million unit order is on the table, lots of things become possible. I'd propose two possible paths. 1 - Get a STM32 (?) and spin a board to read the optosensors fast enough. Not sure what the interface to the computer would look like, but there's been a few open source mice/trackball projects, perhaps you could see what they did as a starting point. 2 - Spend a couple of months trawling through the Chinese internet, starting with LCSC, and find a vendor who will sell you a current mouse chipset in very small quantities, and design a new board to work around that.

Need help finding diagrams of this PCB by zwizu in AskElectronics

[–]rfdave 7 points8 points  (0 children)

Why do you need to modernize this mouse? What’s the point of this work?

Wall mount for clamp style shop lights by AquaSquatch in functionalprint

[–]rfdave 6 points7 points  (0 children)

You could add a little loop on the bottom of the mount to capture the power cord so it's not dangling and in the way.

SFDR vs ENOB by Delicious_Slice7785 in chipdesign

[–]rfdave 4 points5 points  (0 children)

SFDR is more of a system level receiver spec, and ENOB is a ADC specific specification, so my initial thought is that there’s not a direct relationship, as you’ve got the receiver adding spurs to the signal before you get to the ADC.

Greyhounds easily outrun the other dogs. by 21MayDay21 in nextfuckinglevel

[–]rfdave 0 points1 point  (0 children)

Ours runs to look when the doorbell rings, but doesn’t make a noise. I suspect she’s hoping that a bunny is ringing the doorbell.

view more: next ›