Optiplex Micro Internal and/or External Antenna

My understanding is that the standard packaging for some models may only include an internal dual-band WiFi/BT antenna.

According to Intel, two (dual band) antennas are required for optimal functionality.

https://www.intel.com/content/www/us/en/support/articles/000031221/network-and-i-o/wireless-networking.html

https://www.dell.com/community/Optiplex-Desktops/Understanding-Dell-Micro-FF-WiFi-Antennas/m-p/7528483

So you believe the recent Dell micro models come with internal wireless "capability" but the wireless card is an add-on ? 

No, I am saying that "wireless" models may lack the second internal cable, rear-panel RP-SMA socket, and external flex antenna. If you read old messages here it seem that Dell maintained the internal antenna was "good enough" even though Intel's own specs say that both are needed for optimal performance.

"rear-panel RP-SMA socket"=the gold thing the external antenna sticking out of the back screws/plugs into ?

"external flex antenna"=the black antenna that sticks out of the back on some models ?

"second internal cable"=I'm guessing this might be what connects the rear panel RP-SMA to the wireless card ?

Thanks!

Yes, on all 3 questions.

Sorry if my shorthand confused rather than informed.

My situation is I'm in a 100 yr old building-it has plaster walls (with some metal chicken-like wire inside them).  I'll be around 40 feet (and a couple walls) away from the a.c. router.  So I know to look for a Dell with dual band Wifi a.c. capability to take advantage of the a.c. router.  Then from reading the thread you linked me to, it sounds like I should also be looking for a model (like the one you bought) w/the black external antenna in the back.  In other words, the external antenna assists the internal one.   I'm assuming if I see an external antenna then the socket and second cable are already installed.

Yes, if you can hook up an external antenna the best bet would be to get a high gain directional antenna (these usually are flat panel construction) and point it at the router.

The Intel WiFi cards use diversity reception so that the antenna providing the best signal level is preferred. If you hook an external antenna having much better signal it will do most of the work.

If you don't have the socket for an external antenna the best bet would be to use different WiFi hardware; e.g. plug in a USB dongle having an antenna socket, and connect your directional antenna to that.

So if a Dell micro has 2 x 2 Wifi ac is it only using one of those antennas if the external is not hooked up ?  Or do they have 2 internal plus 1 external, for a total of 3 antennas, if the external is hooked up ? 

I see the ProDesk has 2 internal antennas-one in front and one in back.  And it has an optional external antenna connector in the back.  Is that the same setup as the Dell micros ? 

There are only 2 antenna sockets on the WiFi card. It will use whatever antenna it finds.

The socket commonly connected to the internal antenna is shared between WiFi and Bluetooth so that is the default connection.

Don't know, I only researched the configuration I purchased recently. You could probably get the answer in the Dell spuport section by looking at the cutaway views in the service manual.