I have three different WFfi-connected network cameras; a Foscam FI8904, an FI8905, and a “Magion” Chinese knockoff I got on DealExtreme. These cameras are all pretty similar. There are anecdotal stories that the Maygion is really just an unbranded Foscam with custom software, but I haven’t really confirmed this. They’re fairly low-end (among the least expensive in terms of WiFi outdoor security cameras), which means the image quality is mediocre, especially in the brightness extremes of outdoors.
Also, the build quality is not great. Between the three of them, there’s always something going wrong; and AC adapter failing, IR emitters burning out, etc. Replacing the AC adapter is no big deal, and you can actually find replacement IR LED arrays on DealExtreme, so I’ve had some luck replacing those, as well. Twice, now, I’ve had a camera just stop working over WiFi. You’d think this would be a situation where the only option is to toss it out and but a new one, but it turns out it’s not! In both cases I was able to repair the WiFi..for as little as $10! To get that cheap, I had to do some more serious hacking (as I describe near the end of this post) but my first fix was quick, safe, and cost about $35.
I both cases where the wifi quite working, there was no obvious symptom..no errors in the log or anything…it just stopped reporting found wifi networks through the web admin page and no longer connected to my home hotspot. It worked fine via 10baseT. When the first one died, on a whim I decided to crack open the case and see if it was anything obvious, but I had little optimism. The circuit boards inside consumer electronics like this tend to be a nearly incomprehensible array of surface-mounted components – impossible for an amateur like me to repair. In this case, though, I discovered room for optimism.
The rear of the camera can be removed by unscrewing four hex nuts, then carefully pulling the whole assembly out. Inside are a motherboard and a daughterboard mounted to it with a couple of stand-offs. The daughterboard is..you guessed it..the wifi board! Shown here already removed from the stand-offs. it is connected to the antenna and to the motherboard via a 4-wire jumper. These pictures are actually from my second repair (of my Maygion camera), but the two Foscams are almost identical.
Figuring it was still a long-shot, I started googling for identifying markings on the assembly. Turns out it’s relatively easy to find direct replacements for this board! The “model number” on the white sticker, “vnt6656g6a40”, turns up multiple hits.
Interestingly, the identifying product information on the Maygion camera is almost the exact same sticker! They most likely stick one to the outside of the camera because it also shows the mac address.
The first time I made this repair, it was to one of the Foscams. As a stopgap measure to get the “better” (bigger IR emitter array), defective one working, I actually just cracked open the other one and swapped the boards. Bingo! It worked like a charm! I was now confident that a replacement board would do the trick and would be worth the $35. Sure enough, when the new one arrived, it was essentially identical to the original – even the jumper plug was the same. I plugged in the 4-wire jumper and antenna, powered it up, and presto!
This was an easy and convenient fix, but when the wifi died on my Maygion, I started to think this could add up if wifi goes out on a camera every six months or so. Ultimately, I should probably look at a camera with slightly better build quality. There are some in the $200 price range which might be a little better, while still being affordable. Still, there’s no guarantee that these won’t use a similar cheap (and trouble-prone) wifi module. It could be that the power supplied to the daughter board by the motherboard and, indirectly, the AC adapter, is poorly regulated and may be contributing to early failure, but who knows!?
So as I mulled over spending another 35 bucks, I thought about something that had intrigued me the first time around…time for some AustinLightGuy hacking!
The description of the daughterboard on one or more sites is typically something similar to “VIA VNT6656 USB Wireless LAN Module”. Hmmm…USB… Clearly, the 4-wire jumper connecting these things to the motherboards is just a USB connection! Digging a little deeper into the specs, I also found this: “The VT6656 WLAN Controller chip on the VNT6656 USB WiFi Module supports all major Microsoft Windows and Linux operating systems.” If you examine the chip on the daughterboard, it is, in fact, a VIA VT6656, and apparently very common wifi chipset! So i got to thinking, ‘well, what if I just bought the cheapest USB wifi adapter I can find that sports the VT6656 chipset, and the tear it open?’
That’s what I did. I bought this USB stick on ebay (advertised as a “54Mbps Wireless USB Adapter For DELL Latitude, INSPIRON & XPS Laptops”, as an FYI, since I assume the link won’t last forever). It was $9.99 with free shipping. When it arrive a few days later, I immediately removed the one screw holding the case closed, and opened it up. The result is actually comical! Here are two photos showing the camera daughter board next to the wifi USB stick board.
As you can see, these boards are practically identical! Even then component layout is very, very similar. My guess would be that anyone who want to knock out a wifi module just implements one based on a “Typical Application” diagram supplied by then vendor, VIA, or something like that. Anyway, this is clearly hackable.
Next, I figured out which were the corresponding pins on the USB stick by comparing the connector to a standard USB connector pinout.
Piece of cake. Now I just removed the USB connector from the wifi stick, cut the connector of the jumper and soldered the wire right to the stick. (Actually, I first fooled with trying to transplant the micro connector from the original daughterboard, but this surface-mount stuff is really tiny and fragile and I eventually gave up in favor of the brute force approach : )
Cool, now just to connect the antenna…DOH! The connector on the original module is male and the one on the stick is female! Oh well..after abandoning another effort to to reuse the old one, I just cut off the connector and soldered the antenna wire right to the board. Next, I did an experimental power-up and, sure enough, it immediately connected to my wifi – Sweet Success! By the way, when these things boot up correctly, there is a little LED on board which lights up…goes off for just a moment about 10 or 20 seconds in to boot, then turns back on. It also flashes when in ‘discovery’ mode. On dead boards, it’s just remained on all the time.
So, I am now confident that I can repair dead wifi on both Foscam and Maygion cameras for just $10. Not a bad deal.