Garmin Vivoactive 5 smart watch review

I had the watch for one month.

The good,

• bright and crispy touch screen
• not too heavy
  
• snappy UI response
  
• fast GPS fixing
• long battery life (up to 5 days if I do not use GPS)
  

The bad,

• The Garmin Connect app is worse than Apple watch app.
  
• The app cannot work offline. It needs Internet access for syncing even if the watch is connected over bluetooth.
• GPS drift happens at times.
• No wireless charging
   

Ricoh GRIII camera review

I borrow a Ricoh GRIII camera for a week. Here is my take.

The good,

• USB-C port
• Touch screen
• Boots up very quickly
• Sharp lens
• large APS-C sensor has decent dynamic range
  
• Dedicated knob for exposure compensation.
• supports geo tagging
• small form factor. fits in a pocket.
• The lens has a marco mode.
  

The bad,

• The UI is too "simplistic".
• Records video at a maximum resolution of 1080p.
• The screen is fixed. It cannot be tilted.
• No viewfinder.
• The 28mm lens is not wide enough for landscape.
• Auto focusing is slower than SONY RX100 mark 5a.
  

Verdict: GRIII is a very good fixed lens camera for still shoots.

Xiegu X6100 HF transceiver review

The X6100 is a HF and 50MHz transceiver. It is a budget alternative to IC-705 if you do not need VHF/UHF bands.

I tried FT8 on it for a few days.

Good

• Relatively low price
• Bright LCD screen
• The firmware is not locked down.
  
• Internal battery
• Built-in USB interface
• Built-in antenna tuner
• A large community, many hams have the transceiver.
• alternative R1CBU firmware.
  
• The manufacture is still adding new features like wfserver to the firmware.

Bad

• Changing receiver options is tedious due to the untouchable screen.
  
• hamlib's CAT control can be buggy at times.
• Built-in USB interface lacks isolation. Noise from computers would get into the receiver.
• Only 5W output on internal battery.
• It supports WiFi but I never succeeded in connecting to one.
• The CW decoder never worked for me.
• Some birdies exist.
  

Update in Nov 2023,

I sold the transceiver because I lost interest in QRP HF.

Lenovo Thinkpad X1 Nano Gen 2 Review

The good,

• sturdy build
  
• 16:10 matte screen
• weights less than 1kg
• good Linux support
  

The bad,

• The keyboard area gets warm when charging.
• Key travel is even shorter than X1 carbon.
• Keyboard is fused with the palm rest. It cannot be replaced easily.
  
• The internal SSD is from Union Memory, a little-known company in China.
  
• No USB-A or HDMI ports.
• The only two USB-C ports are on the left side.
• Everything except for SSD is soldered on the system board.
  

Conclusion: It is a good ultra lightweight laptop. But compromises were made for the weight. X1 carbon is a much better choice if you need more ports.

Block Internet access for IoT devices on Mikrotik RouterOS v7

I have some IoT stuff at home. They are connected to the 2.4GHz band access point on a MikroTik hAP AX3 router. I want to block them from the Internet while keeping them on the same bridge so that things like Airplay would still work.

One solution is to gather all the MAC addresses of the devices and then add firewall rules to reject packets from them destined to the WAN interface list. This is tedious because I need to keep adding MAC addresses for new devices.

Another solution is to create a dedicated WiFi access point for IoT devices, bridge the WiFi interface with LAN, and then configure the firewall to reject packets from this WiFi interface.

However, simply adding a firewall rule that rejects packets from the new WiFi internet does not work because it is L3 firewall only sees the bridge. We need to use the bridge level (L2) firewall as shown below.

/interface wifiwave2
add configuration.mode=ap .ssid="put_ssid_here" master-interface=wifi-ap-2g name=wifi-no-internet security.authentication-types=wpa2-psk,wpa3-psk .encryption=ccmp security.passphrase="put_wifi_password_here"

/interface bridge port
add bridge=bridge interface=wifi-no-internet

/interface bridge filter
add action=mark-packet chain=input in-interface=wifi-no-internet new-packet-mark=block-wan

/ip firewall filter

add action=reject chain=forward comment=\
    "reject wan access for packets marked block-wan" out-interface-list=WAN \
    packet-mark=block-wan reject-with=icmp-network-unreachable

/ipv6 firewall filter

add action=reject chain=forward comment=\
    "reject packets marked with block-wan" out-interface-list=WAN \
    packet-mark=block-wan reject-with=icmp-admin-prohibited

The config above still allows packets from WAN to reach the devices. But they won't be able to send any packets back.

Belkin RT3200 wireless router review

The Belkin RT3200 is a very cheap ($50 on Walmart) WiFi 6 router based on MediaTek's MT7915 + MT7622 solution. It is extremely similar to Linksys E8450. (Foxconn owns Linksys and Belkin.)

Hardware highlights (source):
 - CPU: MT7622BV (2x ARM Cortex-A53 @ 1350 MHz)
 - RAM: 512MB DDR3
 - Flash: 128MB SPI-NAND
 - Ethernet: MT7531BE switch with 5 1000Base-T ports
 - WiFi 2.4 GHz: 802.11bgn 4T4R built-in antennas
                 MT7622VB built-in
 - WiFi   5 GHz: 802.11ac/ax 4T4R built-in antennas
                 MT7915AN chip on-board via PCIe
                 MT7975AN front-end

The router's stock firmware was okay but sluggish. I followed this to install OpenWrt. Just be sure to 1) backup the factory bootrom; 2) use UBI images ending in itb.

Then I enabled beam forming and BSS coloring and ran iperf3. It achieved ~450 Mbps in both direction between my wireless laptop with Intel AX201 and a wired NAS. The laptop was about 8 meters away from the router.

I then switched the bandwidth from 80MHz to 160MHz. But iperf3 did not show improvements. So I reverted the change.

I also connected EA7500 to RT3200. They negotiated a PHY rate of 1733 Mbps. But the iperf3 test was only ~480 Mbps.

I did not enable WED or HW offloading as I configured the router to be an access point.

Conclusion

If you have a decent 802.11ac wave 2 router, replacing it with RT3200 will not increase the throughput much. But it is a good cheap router if you do not have one yet.

MikroTik hAP ax3 WiFi router review

Update in Feb 2025: The latest firmware v7.17.2 still has WiFi issues.

Update in Dec 2023: The router experienced IPv6 connectivity issues. Rebooting would fix for a few hours. I did not find useful logs. I had to backup, reset, restore.

Update in Nov 2023: Mikrotik added station-bridge mode support in v7.12 wifiwave2 package. And the 11ax compatibility issue seems gone.

Update: I do not recommend hAP ax3 until MikroTik fixes the 11ax compatibility issue.

I bought MikroTik hAP ax³ router last week. Here is my review.

the good

• It has a 2.5GbE port.
• It supports WiFi 6 on both bands. Many cheap wireless routers only support WiFi 4 (802.11n) on 2.4GHz.
  
• It has detachable antennas.
  
• It runs the "RouterOS", which supports OSPF, WireGuard, IPSec, etc.

the so-so

• It only supports 2T2R MIMO and 80MHz bandwidth on the 5GHz band.
  
• I ran iperf3 between an iPad Air 5 and a wired NAS via the hAP ax3 and an old Linksys EA7500. I did not notice any increase in throughput on the ax3.
  
• The RouterOS quick setup did not config IPv6. I had to do IPv6 manually.
• The 2.5GbE port defaults to WAN. I changed it to LAN so that the NAS could use it.

the bad

• I encountered several bugs in the RouterOS.
• One of them is this.
• My Linux devices (two laptops and one router) have problem connecting to the 5GHz band AP if it is in 11ax mode. The error is "Unhandled alg: 0xc0400707". I have to set the AP to 11ac mode.
  
• The MikroTik forum does not show attached files (including screenshots) to guests.
• The new wifiwav2 package does not support four address mode or 802.11s. So you cannot deploy a WiFi mesh without tunneling. 
• The wifi interface's MTU cannot be changed.
  

conclusion

hAP ax3 is okay for people who want the RouterOS + 2.5GbE + WiFi 6. You may also consider the $40 cheaper hAP ax2 if you do not need 2.5GbE or external antennas.