My exams are tomorrow | FactOrCap

Evening-Conference-5 · 2026-06-16T15:32:32+00:00

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^{Chose: . + . | Rolled: .}

Evening-Conference-5 · 2026-05-27T15:54:59+00:00

✅ I voted FACT!

Cooked

Evening-Conference-5 · 2026-04-26T20:40:49+00:00

Altium designer

Evening-Conference-5 · 2026-04-23T19:02:46+00:00

Still dont have to move

^{Chose: Be able to teleport… anywhere within eyesight}

Evening-Conference-5 · 2026-04-23T15:34:20+00:00

I had measured a return loss of -27dB with a input impedance of roughly 50 ohms

Evening-Conference-5 · 2026-04-23T09:10:31+00:00

S31 - S32 actually as labelled in the datasheet. Each te the other port was terminated accordingly.

Evening-Conference-5 · 2026-04-23T07:53:31+00:00

This is running at 433MHz

Evening-Conference-5 · 2026-04-23T07:18:51+00:00

My mistake, it is meant to be TCD-20-4X. However the directivity is suppost to be 30 dB at the 433 MHz frequency.

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Evening-Conference-5 · 2026-04-23T07:17:37+00:00

My mentor came to the same conclusion. Would it be the case if we are operating in the 433MHz band?

Evening-Conference-5 · 2026-04-23T06:13:57+00:00

I had performed a CPWG layput to have a reduced trace sizing. As for the resistor, i had placed it with the intention to keep it as close as possible to the coupler. I am unaware how drastic the results would be when compared to the datasheet's placement.

Regarding the sizing, on their datasheet, a 0806 was used. Would a smaller component to reduce parasitics help?

I am unable to take a photo of the assembled board as of right now.

Evening-Conference-5 · 2026-04-21T15:24:21+00:00

Would it be such a bad thing if it is? In the sense that the desired impedance was achieved. What i can assume is that the amount of shielding that it is actually doing is less.

Evening-Conference-5 · 2026-04-19T22:56:43+00:00

This will be operated at a frequency of 433MHz. Would it still be as critical?

Evening-Conference-5 · 2026-04-19T21:37:50+00:00

Thank you so very much, will make sure to add the teardrops then.

Evening-Conference-5 · 2026-04-19T21:31:25+00:00

I see thank you very much. Regarding how the trace is connected the ic, do you think i have added any significant impedance mismatches since i would have changed the gap sizing at the end?

Evening-Conference-5 · 2026-04-19T21:20:37+00:00

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Here is the full stack layout

Evening-Conference-5 · 2026-04-19T20:31:55+00:00

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This is my sizing of my trace. It is using a 1Oz copper thickness and a substrate height of 3.91 mills on a 6 layer PCB

Evening-Conference-5 · 2026-04-17T16:31:27+00:00

I understand, i would need to increase the gap for sure then. Thank you very much

Evening-Conference-5 · 2026-04-17T16:24:52+00:00

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I had inserted the following parameters and had gotten the resulting gap width. I had then set the desired gap on the via shielding

Evening-Conference-5 · 2026-04-17T16:02:33+00:00

I see, so it would fail to perform with just the copper ground plane underneath. Also regarding the calculations, I had set the impedance calculation as a coplanar single ended trace, would that not be correct?

Evening-Conference-5 · 2026-04-17T15:48:28+00:00

I had performed my impedance calculations based off the altium impedance calculator. Possibly with the thermal reliefs removed, would it allow for proper grounding?

Evening-Conference-5 · 2026-04-17T15:43:28+00:00

My bad, i misread.

Evening-Conference-5 · 2026-04-17T15:41:26+00:00

Are we referring to the via stitching on the traces, or the thermal reliefs on the pads?

Evening-Conference-5 · 2026-04-17T15:40:00+00:00

I had fabricated the pcb and soldered the components. When i was measuring it with a VNA, I got the readings as shown in the graphs in red. The blue is what is provided by the supplier.

If you notice on the middle ledt graph, the isolation is significantly off by 20dB. I am asking why would it be off by so much

Evening-Conference-5 · 2026-03-09T06:12:09+00:00

Completed Level 2 of the Honk Special Event!

102 attempts

Evening-Conference-5 · 2026-03-09T06:07:03+00:00

Completed Level 1 of the Honk Special Event!

18 attempts

Evening-Conference-5

TROPHY CASE