D-Link Wireless AC750 Dual Band Range Extender - DAP-1520 product reviews

There is a frustrating WiFi dead-spot in our building. Not even the stunning BeamForming technology of the recently-installed D-Link DIR-880L router can sneak a signal of any strength around all the metallic clutter in the walls and into this annoying WiFi black-hole.So, when the reviewer we had lined up to test this had to back out for legitimate reasons, I was quick to snap it up for an in-house review. This unit is an entry-level device, not intended to cater to high-throughput environments such as schools or busy offices with sturdy BYOD policies. It is best suited to home or small-office environments where 1-5 devices are wanting to get a solid connection in an are either outside the range of, or in a zone somehow blocked from, the base WiFi access point (AP).

Making use of a horrendously old, but surprisingly rather functional 40m Cat-5 Ethernet cable and a similar power lead, I took my router on a wee tour around our little deadspot, and had a cohort inside the target area with a neat little WiFi signal meter app running on his smartphone to measure signal strengths and thus, hopefully, map out a pathway the signal COULD travel to penetrate this part of the building. Sure enough, a spot was found that if a WiFi access point was placed in there, a strong enough signal would indeed break on through to the other side. A quick eye-ball also confirmed that the target emitter point was also in line-of-sight to the main router's usual home too. Perfect! We had our 'rebound off the side cushion' mapped out! Next, installation and setup...

I am loathe to make use of the now-ubiquitous WPS setup system. Call me old fashioned, but I just don't trust a process I can't 'see' in action. I like to set devices up manually - not only does it ensure I get to know the device better, but it also ensures I know what features are active, and what unnecessary features are deactivated to minimise performance overheads and improve power consumption. So, after securing the repeater in a safe spot on top of a cupboard (Yes folks, you should also quake-safe your networking gear too!) I dived right into the interface using my trusty new HP tablet and a simple web browser. This was actually quite easy to use, and setting up the system at in the most basic manner took less than 10 minutes, including all of my annoying-male habits like tweaking the settings a bit and seeing how that affected the signal strength reports coming from my now-quite-bored accomplice.

Naturally, being a WiFi AC-family device, this uniot handles the regular 2.4GHz band and the newer, more powerful 5GHz band, giving you a lot of options. However, you need to keep in mind how devices like this operate. If you are a techie, skip this next bit... otherwise, please read on for a quick lesson in how radio repeaters work. You have two main options in how it will work - you could think of them as a daisy-chain of people with buckets... in a similar manner as you see in old Western movies when the barn is on fire. Now, in a half-duplex mode, the repeater listens for half a cycle, then transmits for the other half of it's cycle... akin to the person turning to their left to take a bucket from the person at the well, then turning to hand it to the next person in the chain. They can only do one operation at a time and when they have handed off the full one, they have to take a fraction of a second to collect a returning bucket and pass it back upline for a refill. -ping-pong- -ping-pong-

The other style is like everyone facing in the same direction, and reaching back with their left hand to grab a full bucket to pass up the line, while their right hands are sending empty buckets back to the well for refilling. It's more efficient, but in the case of devices like these, it means one band - either the 2.4GHz or the 5GHz - is acting as the 'connection to devices' while the other is acting as the 'connect to base' - you get a trade-off, speed vs reliable connection. No ping-pong, but only one band can be used to shove data between the repeater and the devices. Since many newer devices are 5GHz-compatible (eg. Almost anything that handles 4G or Bluetooth 4.0 is also likely to handle 5GHz WiFi - the "Built For Speed" mentality) this can prove somewhat problematic unless you are happy with your connections dropping to 2.4GHz speeds in the previously no-signal zone. Personally, I'm happy with "slow", because it's better than "none", but some people want to not only have their cake and eat it too, but also want the recipe and the baker on-call to make the next one at a moment's notice... This is not the technology you are looking for... you can move along now.

To cut a long and tedious story short - mainly due to me poking around the GUI trying to find advanced controls and configuration options I reluctantly admitted just weren't available at all - this worked quite well, though not quite as well as I would have hoped. Maybe I'm too much of a tinkerer, maybe I just like exploring all the fine-tuning options... but this device seemed to be extremely automated... so much so I found myself reluctant to really trust it to be doing the very best job it could for me in the situation I wanted it for. While I can't put my finger on any particular bit of data and say "THERE! See! It really should have been able to do better than that!" I can not shake the feeling that it should have been able to do better than give me a mere 22.5db signal gain in the "black hole zone" - less than the difference caused by me opening/closing a single door between me and the main router in a direct line-of-sight situation. Still, as I said earlier, it IS better than no-significant-signal at all.

I think a big part of it's lack of blazing results is that there is no way to over-ride the pre-programmed auto-configurations. User-input is reduced to the barest minimums possible - basically the authentication and real-world physical stuff. If this device could unpack, place and authenticate itself, it probably would... and that would be the last reason for a "fleshie" to be involved at all... gone. Anyway, I'm not going to dive into the technicalities of why this works or doesn't work... I'll leave that for the die-hard hardware junkies and their rigidly-procedural tests etc. At the end of the day, this is not a series of lab tests, it's real-world testing for non-geeks... and on that front alone this device actually comes out looking pretty good. Easy to install, easy to configure, and it... just... works. Simple as that.

Overall, it's functional and simple to use, it's not scary-tech at all. Do be sure to get a tech-savvy friend or family member to check the firmware for you though, because D-Link have a habit of rolling out devices and then adding new functionality within a few months via a firmware upgrade. This can make a lot of difference in terms of performance boosts and feature add-ons, especially if consumers start crying out for a little more user-level tweakability. If you are finding that the kids are complaining of signal drop-out or jerky videos streaming to your PS4, then this may be the solution for you. Remember though, it needs to be roughly half-way between your current router and the target device(s) for best results. Move it too close to one end or the other and you'll start to see performance losses and may incorrectly blame the device, when it's actually the location, location, location.