Not buying / not selling - just some info - Page 1
Forum section: electronics / general

author: brainwash
author_rank: Frequent Contributor
timestamp: November 13, 2012, 10:14:07 pm
content: I just bought two presumably Bluetooth modules JY-MCU. They are advertised as bluetooth transceivers, pairing with any bluetooth module or phone and such. The PCB looked kind of empty but I did not worry at the time. Well, actually that's the thing, it's just the barebones PCB - pins, led, translation transistor and some reverse protection diode, but the actual transceiver chip is missing.Had to find one listing in Chinese to actually figure out why the module was not responding:http://item.taobao.com/item.htm?spm=a1z10.1.w4.16.Y7XxlW&id=10203626135I'm sure the parts can be somehow reused and I've paid <5E for both including shipping from UK, no big loss. Just a heads-up for anyone falling into the same trap. Seller has been contacted, let's see how this goes.For all people growing tired of wiring up their serial port to do printf debugging, these boards are a nice option. Added bonus, you can do that via a smartphone (Android).

author: GeoffS
author_rank: Unknown
timestamp: November 14, 2012, 01:47:27 am
content: I think you got what was advertised. The Chinese text does say that no Bluetooth function is present and to buy a Bluetooth module. (courtesy of Google translate)Maybe someone here who actually speaks the language can do a better translation.

author: brainwash
author_rank: Frequent Contributor
timestamp: November 14, 2012, 01:52:03 am
content: I did not buy it from there, I bought it from ebay.de with an English description, sent from UK:"Interface Base Board Serial Transceiver Bluetooth Module Für Arduino MEGA UNO R3""2.Works with any USB Bluetooth adapters."I found the Chinese description, even after translation, to hold more truth than the original auction, that's why I linked it. I'm not linking the original auction for obvious reasons.

author: T4P
author_rank: Super Contributor
timestamp: November 14, 2012, 10:04:36 am
content: The auctioneer's listing lied to you but the original one really doesn't have bluetoothbecause the one with bluetooth looks like this

author: iloveelectronics
author_rank: Frequent Contributor
timestamp: November 14, 2012, 10:37:49 am
content: You need to put one of these on top of the PCB you've got:http://item.taobao.com/item.htm?spm=a1z10.3.0.98.5Tww0O&id=14777982900&to make one that looks like the one T4P posted above.Basically you've only got an adapter board that makes the power and communication pins more easily accessible. You're missing the core bluetooth module.The same seller on Taobao has the finished product as well:http://item.taobao.com/item.htm?spm=a1z10.3.0.84.apoXEh&id=14372426867&

author: peter.mitchell
author_rank: Super Contributor
timestamp: November 14, 2012, 11:07:07 am
content: Wow, thats actually pretty nifty, and in quantity I'd expect them to be quite affordable too!

author: brainwash
author_rank: Frequent Contributor
timestamp: November 14, 2012, 11:21:25 am
content: I know the issue is obvious, especially after my initial post.The info is there so people dont't fall into the same trap, even though the seller might have good intentions. So just make sure that the board area is fully populated.The module can be found on a lot of websites, including dx, for single digit dollar prices. There is some information on the web from various diyers because the module has several modes of functioning that can be triggered with modem-like commands via serial. But even without those it works out of the box as 9600n1 and default BT pw 1234.