Aliexpress radio modules - suppliers etc - Page 1
Forum section: electronics / general

author: MarkR42
author_rank: Regular Contributor
timestamp: October 11, 2020, 12:22:06 pm
content: Hi,I'm making a low-volume product which contains a radio module made by company-unknown in China, which I can get from many Aliexpress drop-shippers. The module is known by several part numbers including MD7105-SY. It is a simple board with a A7105 radio chip and some passives and a pcb antenna. I assemble the "finished" product (it is for hobbyists anyway) by just soldering the module to a commercially manuactured board I've designed.So far so good, the Aliexpress drop-shippers are cheap and efficient, although the quality is a little bit variable (I've had only a small number of dead-on-arrival boards), the modules don't seem to vary much and are all made to the same design- no noticable differences from one batch to the next.Right now it's all fine, but I'm a little worried about- What happens if the drop-shippers' supply dries up?- What happens if the quality of the boards diminishes?I don't know who makes this module, or how to place orders from further up the supply chain. Maybe they won't be interested anyway, because I won't be ordering 10k pieces.NB: This is not my day jobShould I?- Just keep buying them from the Aliexpress drop-shippers?- Design my own replacement and have it manufactured? It would be much more expensive but I could incorporate some design changes. There would also be a bit of work involved making prototypes, testing etc.- Do I have any other options?Ideas please.

author: SMTech
author_rank: Frequent Contributor
timestamp: October 11, 2020, 04:56:39 pm
content: It looks popular, almost a goto module for arduino types, I doubt you have anything to worry about. That said, at a glance it also basically looks like the reference design, so you could probably make your own version in one iteration or build it right into the main board. Your commercial build partner should be able to source the part for you at a reasonable price perhaps working out at zero extra cost if integrated.

author: MarkR42
author_rank: Regular Contributor
timestamp: October 11, 2020, 08:33:38 pm
content: Quote from: SMTech on October 11, 2020, 04:56:39 pmDo not overestimate my competenceQuoteYes, I am sure they'd be able to source the part.The main difficulty with integrating it is that it will make the whole thing bigger and more complex, I had a play with 2-layer designs and it looks quite tricky, so either I would have to use a 4-layer board, make my own castellated module, or make the main board a lot larger (that really does not appeal). Still might be an option if I ever do a major respin (think V2.0) of this thing.

author: Mangozac
author_rank: Frequent Contributor
timestamp: October 11, 2020, 09:55:16 pm
content: As a low-volume product I wouldn't lose any sleep over it. If you do find that they start getting harder to get you could buy up some additional stock to get you by while you either find an alternative or design the radio circuit in.

author: NorthGuy
author_rank: Super Contributor
timestamp: October 12, 2020, 03:49:28 pm
content: The chip itself is 50 cents, so you most likely will save money if you integrate it directly onto your PCB. But you always can do this later, if the module supply dries out, or if your sales go through the roof, or you decide that your own design is cleaner or better, or ...

author: 48X24X48X
author_rank: Frequent Contributor
timestamp: October 12, 2020, 04:41:40 pm
content: I think NRF24L01 is a compatible part with A7105? If yes, there are many variation of them from better known manufacturers in China. Some with even FCC and CE certification. Pin out might be different though.

author: MarkR42
author_rank: Regular Contributor
timestamp: October 12, 2020, 06:33:35 pm
content: Quote from: 48X24X48X on October 12, 2020, 04:41:40 pmNo, unfortunately not. They have many similarities, but the radio system is not remotely compatible you can't just throw in any chip which uses the same frequencies and a similar bus interface.I don't understand radios, they are magic, but there are things like modulation schemes and error correcting codes which are very specific to the chip (and indeed, its many vaguely documented settings).

author: Kjelt
author_rank: Super Contributor
timestamp: October 12, 2020, 09:01:53 pm
content: Do a powerbuy so you have a years stock, at these prices you can never come close with your own design.

author: asmi
author_rank: Super Contributor
timestamp: October 13, 2020, 07:35:17 pm
content: Yea, I would also buy a big patch, and keep it as a rainy day supply in case I won't be able to source them anymore. This stock should give me enough time to either find a replacement, design my own replacement, or just slowly EOL the product if none of above options are feasible.

author: Simpleton
author_rank: Newbie
timestamp: November 12, 2020, 07:27:30 pm
content: A gang of diy rc builders on mode-zero.uk had problems with dodgy nrf24lo1+ chips built into chinese modulesone of the forum-ites enquired about getting a batch made by jlcpcb who, it seems, are legit re-sellers of the nordic chipsprice was comparable with the more reliable aliexpress vendorsre rf circuitry: when weight is more important than rf niceties the rcgroups.com forum threadbuild a diy flysky/turnigy rx from SCRATCH!will be of interest.although a 27meg valve tx and a crystal rx might allow lighter weights!