A few weeks back I asked for opinions of the TrangoLink-45 radios. Since then I've installed two pairs and figured I'd share my experiences with the list.
Physical design. The antenna and radio housing are solidly built and look like they will last. However, the mounting system is not as well designed as the rest of the radio. First, it is made of zinc plated steel, which I suspect will rust after a while. The mount uses a U-bolt to attach the radio to a pole. This is a problem because it makes it difficult to hold the radio in place and hand-tighten the nuts during installation. Since there is no hoist loop in the radio housing, you can't tie the radio off to the tower and use both hands to tighten the u-bolt. Also, the mount is specced to work with up to 3" diameter poles, but there is no way it will work on anything over 2". The telnet interface for radio configuration is simple and effective. Never having used a Trango radio before, it took me about 30 minutes to be completely comfortable with the radio setup and management interface. SNMP support looks good but I haven't gotten this set up on my network yet. One little plus is the PoE pinout and voltage is compatible with Canopy gear- this radio plugged right into a CTM-1m once the timing pulse was switched off. DFS. The radar avoidance DFS on these radios works by using a separate receiver circuit to compare the instantaneous received power level to a threshold. Anything coming into the receiver port over that threshold is considered a radar event and initiates a channel change. In my case, I had a weather radar tower less than a mile from one of the radios. The tower transmits with an EIRP of 6.9 GW (yes, gigawatts) at 5500 MHz. Emissions outside of the radar's licensed band were enough to trigger DFS sporadically throughout the 5.3 and 5.4 bands. Do a thorough spectrum analysis before deploying these radios or be prepared to spend a lot of time troubleshooting later. Performance. I haven't done thorough testing yet but I'm getting almost zero ARQ retransmissions and the highest modulation mode on my 1/2 mile link, so about 35 Mbps of TCP throughput sounds reasonable. Network issues. #1 is that there appears to be a bug with the new VLAN implementation for the radio's management interfaces. The radios won't respond to any traffic not originating outside of its subnet. My packet sniffer shows pings going into the unit from a machine on the local network segment and one on another network, and replies are only generated for the machine on the local network. Trango engineering is working on the problem. Second, I was getting ethernet errors when connected to a Cisco Catalyst 3548 switch. This was difficult to track down because there are no CRC error counters available in these radios and there is no way to hard-set Ethernet speed and duplex settings. Putting a cheapo netgear unmanaged switch between the Cisco and the Trango eliminated the errors. According to Trango, they cannot implement manual speed and duplex settings due to hardware limitations (wtf?). Anyway, sorry for the manuscript. All in all, decent set of radios for $2000. A little rough around the edges compared to the Orthogons I am used to, but the performance is better and you can't beat the price. Patrick -------------------------------------------------------------------------------- WISPA Wants You! Join today! http://signup.wispa.org/ -------------------------------------------------------------------------------- WISPA Wireless List: [email protected] Subscribe/Unsubscribe: http://lists.wispa.org/mailman/listinfo/wireless Archives: http://lists.wispa.org/pipermail/wireless/
