Path: ...!news.mixmin.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail
From: "Don" <g@crcomp.net>
Newsgroups: sci.electronics.design
Subject: Re: ESP32
Date: Tue, 30 Jan 2024 18:30:30 -0000 (UTC)
Organization: A noiseless patient Spider
Lines: 40
Message-ID: <20240130a@crcomp.net>
References: <ohcgrihg7g5djr0i7c60mc9bm2sq2b2jkn@4ax.com> <xnplxi7qk1.fsf@delorie.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Injection-Date: Tue, 30 Jan 2024 18:30:30 -0000 (UTC)
Injection-Info: dont-email.me; posting-host="fbe1d59af9d6f69349a730d9120a64be";
	logging-data="1167989"; mail-complaints-to="abuse@eternal-september.org";	posting-account="U2FsdGVkX1888M5yJZtqB5pCm3WDmph2"
Cancel-Lock: sha1:PvUTQSQvHM5SKW57iNHhCKI0rDE=
Bytes: 2259

DJ Delorie wrote:
> john larkin writes:
>> Has anyone used any of the ESP32 parts? That's the Expressif Systems
>> family of uP's.
>
> I have a friend who uses them so much he buys them in bulk, just for
> personal use.  One key thing to note though: there are a lot of people
> making adapters for these, and not all do it correctly.  The ESP32 is
> the module, not the adapter!  The module has an antenna on it and a lot
> of the adapters place that antenna over their ground plane, rendering it
> useless.
>
> Example:
>
> Note here that the black tab next to the shield is within the adapter's
> footprint: https://www.amazon.com/dp/B08D5ZD528
>
> Compare to this one where that tab, the antenna, is off the edge:
> https://www.amazon.com/dp/B0CDRM6BGQ

Very interesting. Thank you for the tip.

* * *

As an aside, WiFi antennas always attract my interest. Here's the two
intregrated antenna arrays in a Cisco exposed:

    <https://crcomp.net/misc/cisco/1.png>

Given its larger element size, the left likely covers 2.4 GHz while right
uses 5 GHz. The left elements are approximately 8.5 mm above the ground
plane while the right are about 5.5 mm.

Danke,

-- 
Don, KB7RPU, https://www.qsl.net/kb7rpu
There was a young lady named Bright Whose speed was far faster than light;
She set out one day In a relative way And returned on the previous night.