Hi,

Sometimes then I start inSSIDer 4.2.2.13 on MacOSX El Capitan 10.11.4 on a MacBook Pro (Retina, 13-inch, Early 2015)
it will just show a few SSIDs, as shown in the picture

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Name:	inSSIDer 4 Mac.png 
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ID:	1111

But the Mac / airport can see a lot:

bash-3.2# airport -s
SSID BSSID RSSI CHANNEL HT CC SECURITY (auth/unicast/group)
StockholmPublic 18:33:9d:5f:05:ed -79 104,-1 Y SE NONE
wlan.stockholm.se 18:33:9d:6c:17:70 -82 6 Y SE WPA2(802.1x/AES/AES)
Prat 9c:5d:12:24:47:94 -79 6 Y GB WPA2(PSK/AES/AES)
SUNET-GUEST 58:b6:33:38:de:08 -76 7 Y SE WPA2(PSK/AES/AES)
NUNOC 00:22:90:92:b1:6f -80 64,-1 Y SE WPA2(PSK/AES/AES)
NUNOC-GUEST 24:b6:57:7a:c7:11 -43 1 Y SE WPA2(PSK/AES/AES)
StockholmPublic 18:33:9d:5e:a9:32 -52 1 Y SE NONE
UB-GUEST 5c:50:15:c9:4f:35 -75 13 Y SE WPA2(PSK/AES/AES)
guest.stockholm.se 18:33:9d:6c:17:7e -85 40,-1 Y SE NONE
wlan.stockholm.se 18:33:9d:5f:05:ef -78 104,-1 Y SE WPA2(802.1x/AES/AES)
wlan.stockholm.se 18:33:9d:5e:a9:3f -64 132,+1 Y SE WPA2(802.1x/AES/AES)
pcab dc:9f:db:1c:9d:3a -54 11 Y SE WPA(PSK/AES,TKIP/TKIP) WPA2(PSK/AES,TKIP/TKIP)
UB-COMPATIBLE 5c:50:15:c9:4f:36 -78 13 Y SE WPA2(802.1x/AES/AES)
wlan.stockholm.se 18:33:9d:6c:1a:5f -84 36,+1 Y SE WPA2(802.1x/AES/AES)
NUNOC-GUEST 24:b6:57:8c:c7:7e -90 56,-1 Y SE WPA2(PSK/AES/AES)
eduroam 58:b6:33:78:c4:78 -40 8 Y SE WPA2(802.1x/AES/AES)
StockholmPublic 18:33:9d:5f:05:e2 -62 11 Y SE NONE
NUNOC-GUEST 00:22:90:92:b1:6e -80 64,-1 Y SE WPA2(PSK/AES/AES)
pcab dc:9f:db:1b:9d:3a -80 56 Y SE WPA(PSK/AES,TKIP/TKIP) WPA2(PSK/AES,TKIP/TKIP)
NUNOC 24:b6:57:8c:c7:7f -89 56,-1 Y SE WPA2(PSK/AES/AES)
StockholmPublic 18:33:9d:5e:a9:3d -64 132,+1 Y SE NONE
NUNOC-GUEST 24:b6:57:7a:c7:1e -51 132,+1 Y SE WPA2(PSK/AES/AES)
guest.stockholm.se 18:33:9d:5e:a9:3e -64 132,+1 Y SE NONE
NUNOC 24:b6:57:7a:c7:1f -52 132,+1 Y SE WPA2(PSK/AES/AES)
eduroam 58:b6:33:78:d4:ac -52 128 Y SE WPA2(802.1x/AES/AES)
SUNET-GUEST 58:b6:33:38:d4:ac -53 128 Y SE WPA2(PSK/AES/AES)
Stampen-managed 50:06:04:fc:dc:33 -85 11 Y SE WPA2(802.1x,Unrecognized(0)/AES/AES)
KeetoExpress f0:b4:79:03:56:af -81 11 Y SE WPA(PSK/TKIP/TKIP) WPA2(PSK/AES,TKIP/TKIP)
wlan.stockholm.se 18:33:9d:5f:05:e0 -63 11 Y SE WPA2(802.1x/AES/AES)
NUNOC-GUEST 00:22:90:92:b1:61 -66 11 Y SE WPA2(PSK/AES/AES)
SUNET-GUEST 58:b6:33:38:d4:a8 -63 11 Y SE WPA2(PSK/AES/AES)
eduroam 58:b6:33:78:d4:a8 -63 11 Y SE WPA2(802.1x/AES/AES)
remote 30:5a:3a:73:5a:50 -79 6 Y -- WPA2(PSK/AES/AES)
StockholmPublic 18:33:9d:6c:1a:52 -63 6 Y SE NONE
UB-GUEST 5c:50:15:c9:89:75 -82 6 Y SE WPA2(PSK/AES/AES)
UB-COMPATIBLE 5c:50:15:c9:89:76 -82 6 Y SE WPA2(802.1x/AES/AES)
DOBB-STUDIO 88:1f:a1:3a:5b:96 -80 6 Y SE WPA2(PSK/AES/AES)
REMOTE54epsw 00:1d:c9:08:39:05 -69 3 N -- WPA2(PSK/AES/AES)
guest.stockholm.se 18:33:9d:5e:a9:31 -52 1 Y SE NONE
CWNA_WPA2_5G 20:3a:07:f6:b7:20 -48 48 Y -- WPA2(PSK/AES/AES)
Prat 9c:5d:12:24:47:a4 -90 44 Y GB WPA2(PSK/AES/AES)
eduroam 58:b6:33:39:3e:7c -77 44,+1 Y SE WPA2(802.1x/AES/AES)
CWNA_WPA2_5G 20:3a:07:f6:62:90 -66 44 Y -- WPA2(PSK/AES/AES)
CWNA_OPEN_5G 20:3a:07:f7:1a:20 -63 40 Y -- NONE
StockholmPublic 18:33:9d:6c:1a:5d -81 36,+1 Y SE NONE
CWNA_OPEN_5G 10:bd:18:c9:59:30 -70 36 Y -- NONE
eduroam 58:b6:33:78:de:0c -72 108 Y SE WPA2(802.1x/AES/AES)
SUNET-GUEST 58:b6:33:38:de:0c -72 108 Y SE WPA2(PSK/AES/AES)
eduroam 58:b6:33:78:c4:7c -38 104 Y SE WPA2(802.1x/AES/AES)