eric

10 MHz - 6 GHz RF front end board

Local oscillators and FPGA clock board

Base board where four RF boards, one clock board, and one FPGA SOM plug into. Provides power and IO between PCBs.

Castellated baseband filter board, so it can be revised without respinning the entire RF board.

Now we wait for fabs to arrive 🤓

Starting the reflow oven build

Receipt of an Aisler PCB fabricator order, including a small donation for Kicad EDA software

I like that you can donate to @kicad.org via @aisler.net checkout. Pretty convenient way to contribute a little bit!

Just need to order this stupid thing already

Finally have the bench set up, with a new ESD mat, lab chair, and lighting.

Toaster oven and reflow kit arrived!

Red: top layer, green: layer 2, blue: bottom layer.

One thing I like to do for high speed signals is tighten the inner reference plane clearance. This minimizes the via impedance discontinuity. The green is the reference layer (L2).

PCB designs printed on paper to make sure everything fits how its designed

Sanity checking my assembly

I found a new/unassembled controleo2 kit and toaster oven on eBay for like 1/3 the cost of a new kit 😁 hopefully the older version works well!

The urge to order boards right after finishing layout instead of reviewing

Curvy RF traces 🧐

Top side layout

Bottom side layout

Pretty satisfied that I could fit my whole RF front end on a 4L @aisler.net stackup using only outer layers for controlled impedance (still work in progress)

Unreal tournament 2003

Top layer

Bottom layer

Power layer 1

Power layer 2

Almost done routing this 6L board, just need more GND vias, mounting holes, clean up tracks/pours. Probably didn’t need that length matching but it makes FPGA timing easier to meet (100MHz). Next is to work on the RF cards and clock board 🧐

Has anyone compared an Adafruit EZ-make reflow oven to Controleo3 reflow kit?

Screenshot from Vivado development software for FPGAs

Messing around in Vivado confirms that I never want to be an FPGA engineer.

Very curious about this too.

Meet HackRF Pro! HackRF Pro is a Software Defined Radio peripheral capable of transmission or reception of radio signals from 100 kHz to 6 GHz.

You can read more about HackRF Pro and preorder it now from select resellers here: greatscottgadgets.com/hackrf/pro/

Polarization can help to read part markings without the glare

“Base” board for an FPGA SOM in the middle, 4 RF channels (two along the top, two along the bottom edge), clock/LO generation board on the left. Power supples are on the bottom of the base board.

Base board for my radio project. Biggest hobby board I’ve designed, 6L 8x5 inches. Almost have to use JLCPCB since the cost from any other fab would be outrageous. Backplane would be better if this moves to a product but I like being able to debug/probe/respin boards separately for prototyping!

another one! this time, it's a super interesting bipolar current source that needs only one op-amp and one resistor!

schematicsforfree.com/files/Power%...

I'm using one of Murata's gate drive supplies, with only 3 pF primary-secondary capacitance

Picture of a PCB layout with three groups of components for a mixer LO, demodulator LO, and digital sampling clocks.

LOs/clock generation board

I had to do this on an Xbox or PS5 (can’t remember which) and I had the same experience lol. Took tons of heat. No clean flux doesn’t do crap, need the gooey kester stuff

Keep an eye on Craigslist or marketplace. I got my Nikon for around $250. More common than you’d think

Picture of the book: art of electronics the x chapters

📚

Screenshot from KiCad PCB layout showing traces with length matching serpentines.

Ugliest length matching

Picture of a cluttered electronics workbench

Ignoring the mess I am pretty happy with my workbench, but it is a bit bigger than I had hoped (long story). Lots of space for the microscope and other stuff though!

From the rfelectronics community on Reddit: Working on My Own 3D EM Solver Explore this post and more from the rfelectronics community

Really excited to be able to import PCB gerber files for 3D EM simulation. www.reddit.com/r/rfelectron...