A few days ago, to upgrade my not-so-smart TV, i bought an HDMI dongle that’s been having a lot uf success: MK802IV.
It’s features make a lot of smart phones shy away:
– CPU: Rockchip RK3188 quad core ARM Cortex A9 1.6 Ghz
– GPU: ARM Mali 400 MP4 500MHz
– RAM: 2 GB DDR3
– Storage: 8 GB Nand Flash
– Networking: WiFi chip Broadcom AP6120 & BlueTooth
– Connections: 1 USB Host 2.0, 1 micro USB for the power supply, 1 USB OTG
– Expansion: micro SD slot
All this for a price tag of 74€ from Amazon.it (on Ebay it’s easy to find them at a better price). Everything would seem perfect, even by reading the reviews of a lot of people that seem really happy of their purchase: well then, all i need to do now is connect it to the TV. Good.
First power up, everything starts without any problems, the interface seems decent and the general fluidity, even if not impeccable, is accebtable. Not bad as a start. Ok, i’ll connect to my home Access Point, I want to test it right away with youtube and see some spectacular videos: done.
I opened youtube, accessed my Google account, waited a few moments but that’s normal, it had to synchronize everything. And now i opened the first suggested video (strangely from GoPro), a moment of buffeting and… there it goes: look how good the quality is, the fluidity… the… the… the… video’s blocked again for buffering?
So yes, i checked the settings of the WiFi antenna signal and it says that it’s good, but at a constant speed of only 12Mbps: after various suggestions of changing the ROM from the stock one to a better one, i only get a marginal improvement, but not enough to use this dongle for streaming FullHD videos.
I don’t get up and i talk about it to Matteo, that works here at the UWiC Lab on VirtualSense, antennas and wireless comunication day and night. And so we try to recreate the conditions in which the dongle is when at my house: we don’t get the same performance but we get close, and oscillating 12-19 Mbps against the fixed value of 12Mbps. The tests can now start.
The first try with the stock dongle gets us a transfer rate of 5Mbps.
And so the fist mod is very simple: open the stick and bring the antenna out to limit the interference with the internal components.
This mod, even if it’s quite simple, really brought some important improvements. The signal speed in the settings menu is now in the 54Mbps range, keeping a “good” signal. This, in substance, mean an effective transfer rate of 10Mbps: much better, but we’re connected to a LAN, so i would like to get more.
At this point we’re getting delirius and we decided to do something that makes the restrained dimensions of the dongle go to hell, and one of it’s advantages now becomes a drawback: this Linksys Rp-TNC antenna has a 2.2dBi gain and not so restrained dimensions. But we’re doing everything in name of the Mbps.
Ok, now we can see that Matteo substituted the small original antenna with this gem: after all, the dimensions didn’t change much (or at least the order of magnitude didn’t change, we can still use a traditional meter to measure it’s dimensions).
With this new mod, the connection speed stayed around 54Mbps but the quality now moved to “great”:
“at least we gained a few Mbps”
… the last famous words.
Doing the usual trasfer rate test, we were stoned: an effective speed between 23-24 Mbps!!! We can’t ask more from this dongle (in Wifi), we’ve touched the top.
Summing up, we encountered the following situations:
– MK802IV stock, connection at 12-19 Mbps, speed of 5Mbps;
– MK802IV with stock external antenna, connection at 54Mbps, speed of 10Mbps;
– MK802IV with Linksys Rp-TNC, connection at 54Mbps, speed of 23Mbps.