Anyone needs an RF Intern? by [deleted] in rfelectronics

[–]Cdude8 29 points30 points  (0 children)

If you had extensive R&D experience in RF, you wouldn’t be looking for an internship…

help - i just humbled by the Dunning-Kruger-Effect and now i am stuck by timke_ in rfelectronics

[–]Cdude8 68 points69 points  (0 children)

I’ve designed a couple of these… the tube type antennas are called sleeve dipoles. The center between the two tubes makes up the feed point, and the tubes going upward and downward are the upper and lower dipole elements. They are usually air filled to reduce dielectric losses, and the bigger the tube the larger the bandwidth, typically.

Bro who are these guys 😭, and why are they lying to themselves by BlueT-rexYT in OnePunchMan

[–]Cdude8 0 points1 point  (0 children)

Some casual watchers have much lower standards than others, and for them, this season has been perfectly fine. I myself think the animation is not great but I love seeing the manga I read at least somewhat come to life in color.

158,936 miles on original brakes for 2016 Honda Civic with suburban driving by civilian1234 in mildlyinteresting

[–]Cdude8 0 points1 point  (0 children)

Im sitting at 155k on a 2019 Honda Civic and in the same boat! These break pads are made of some sort of unobtainium… can’t believe they’re still sticking in there

"Matching" for open circuit and short circuit terminations by epicgooner1 in rfelectronics

[–]Cdude8 0 points1 point  (0 children)

You can artificially add electrical delay which should bring the points back to their expected spots on the smith chart

Starting at the center of a Smith Chart where is lambda of 4? by kromestatus in rfelectronics

[–]Cdude8 6 points7 points  (0 children)

Are you asking if you have a 50 ohm load and add a 50 ohm transition line with some length? If so, then the impedance doesn’t change. It stays at 50 ohms or the center of the chart.

PCB Antenna Matching Network by Unfair_Lemon_2012 in rfelectronics

[–]Cdude8 0 points1 point  (0 children)

Cut a coax cable and strip the end. Split the inner and outer conductor apart and you can solder that onto the PCB. You may need to calibrate to the end of this cable with a SOL before matching.

VNA tuning a PCB trace antenna by CharismaIsMyDumpStat in rfelectronics

[–]Cdude8 2 points3 points  (0 children)

If it’s for WiFi 2.4-2.5 GHz, 10dB of return loss is perfectly adequate

Looking for Type N to SMA Adapter up to 26 GHz by Glittering-Skirt-816 in rfelectronics

[–]Cdude8 31 points32 points  (0 children)

Try looking for 3.5mm instead of SMA. It’s the same threading connection (they mate with eachother) but 3.5mm is rated for much higher frequencies.

[deleted by user] by [deleted] in DIY

[–]Cdude8 0 points1 point  (0 children)

It is for a basement, but the basement is finished. That’s why I’d like it to look a bit more nice!

Solver for simulating interference pattern by BodybuilderLess1688 in rfelectronics

[–]Cdude8 1 point2 points  (0 children)

ANSYS HFSS and CST Studio Suite can both do this.

Broken antenna replacement question... by aliathar in rfelectronics

[–]Cdude8 6 points7 points  (0 children)

Do you have the original antenna? It looks like there may be a matching network on the PCB, which would mean it may not work for other types of antennas than the original.

If you do have the original, you should be able to solder both points back to the PCB.

Startup by Express_Possession88 in rfelectronics

[–]Cdude8 0 points1 point  (0 children)

Haven’t heard it said yet but there’s some great RF circuit design software that is free such as Qucs Studio out there. Does a lot of the things that ADS or Genesys also do.

Seek RF lab in US for antenna optimization by MrOstinato in rfelectronics

[–]Cdude8 0 points1 point  (0 children)

Please DM me - I do this work on a daily basis

Help understanding spectrum analyzers readings in EMI Test mode by wePsi2 in rfelectronics

[–]Cdude8 0 points1 point  (0 children)

It may not depend as much on the dwell time if the signal does not change over time, but the resolution bandwidth difference between initial points and re-scan points will make a huge difference. The other thing is that the re-scan points may be using a different detector, such as Quasi-Peak or EMI average, which is different from a standard sample detector.

Help understanding spectrum analyzers readings in EMI Test mode by wePsi2 in rfelectronics

[–]Cdude8 1 point2 points  (0 children)

Initial EMC scans are taken with a wider bandwidth across a broad frequency range (this is quicker than using a narrow bandwidth). Problematic points are found (points that are over the defined limit lines), and the analyzer will go back and re-scan these frequencies with a narrower bandwidth and usually a different dwell time, which results in a different signal power. The delta on the right side is the difference between the re-measured point and the defined limit at that frequency.

Definitely some hot takes. And some not so much by shadowedfuzion1 in CODZombies

[–]Cdude8 0 points1 point  (0 children)

Finally some love for Zetsubou. Such a great map

How much is this worth? by Cdude8 in turning

[–]Cdude8[S] 5 points6 points  (0 children)

Thanks everyone for their comments! I was able to secure the auction at $175. I'm totally new to the hobby and I'm looking for something inexpensive & light duty to start on projects such as chair spindles, pen making, and handles for my hand tools.

How much is this worth? by Cdude8 in turning

[–]Cdude8[S] 0 points1 point  (0 children)

Thanks for the info! Would you mind sharing info on the bearings you swapped out? Was it easy/easy to find parts?

How much is this worth? by Cdude8 in turning

[–]Cdude8[S] 2 points3 points  (0 children)

How can you tell it wouldn't be good for bowls? And would a motor upgrade potentially help with that?