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0

You need to educate yourself a bit in antenna matching theory and procedure. Very short: Find impedance Z in mid frequency of the plain antenna with 0E jumper. Use smith chart to transform this Z into 50 Ohms. Get component values of the filter from smith chart. Measure and re-iterate until your return loss is at least below -10dB over the entire band of ...


1

Your plots look they're for return loss, RL. This is measured in dB, not ohms. So you're reading 0 dB of return loss at 2.45 GHz, not 0 ohms. Note, 0 dB return loss is very bad, and means you have a very poor match.


2

Yes, it is almost certainly possible. I'm not sure exactly which part you are asking about. One way of looking at it is that the brightness of the LEDs will depend mostly on two things: The efficiency of the LED (in converting electrical power to light). The power consumed by the LED. So, you could just replace your LEDs with more efficient ones (without ...


5

This should be a Littelfuse SMD resettable fuse. The miniSMD series provides surface mount overcurrent protection for applications where space is at a premium and resettable protection is desired. https://www.littelfuse.com/products/polyswitch-resettable-ptcs/surface-mount/minismd.aspx


4

Shunt resistor, 0.010 ohms, common on laptop battery PCB.


5

In theory, you'd expect overlapping pads to solder together, if assembled with solder paste. In practice, they probably would, but you'd be unable to inspect the joints. The way this is normally solved in the industry is to use plated through half holes, also known as castellated pads. This image of a module intended for surface mounting is from sparkfun. ...


1

The normal approach is not to join the two surfaces, but to join the edge of the top board to the top surface of the one below. To ensure maximum solder adhesion and provide a plated copper edge to solder to, the top PCB will have castellation edges. (As a commentator points out, the pads themselves do not melt at reflow temperatures! It's the solder that ...


11

Most contract fabrication houses would load up all their feeders and then make the run of boards for those components and then cycle back through the boards for the next load of components in the feeder. There are practical limits however including how many boards the factory can stage at one time, how long the solder paste stays able to accept additional ...


10

You feed the batch through the machine 4 times. Solder paste has hours from application to soldering, it will be fine.


1

There is such thing as PCB cut-out. You can make it exactly in a shape of sawtooth hanger near the top of pcb. Another simple option is to use right-angle rectangular header with pins facing down. If your PCB is heavy you can use either shrouded or dual row headers.


1

Try using SMT PEM Nuts this may work you will need to choose a low profile Nut.


1

In this case, I'd choose 1206 for an uncrowded board, simply because it's easier on my old eyes. If the board is crowded, I'd choose 0805, or even smaller, to save space. The other answers have demonstrated that there is no electrical reason to prefer one over the other here.


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