GSM To Landline Box Has A Creatively Soldered Cellphone Inside


We don’t blame the manufacturer of this GSM to Landline converter box for not designing the thing from the ground-up. After all, quantities of scale have made dumb-cellphones available for next to nothing. But you have to admit that it’s interesting to see a fully populated cellphone board creatively soldered into a consumer product. It would be commonplace if made in your basement rather than being sold in a store.

[Anton] was using the box to add his analog house phones to the cell network. The signal strength at home is pretty low and this box offers an external antenna for better reception. He cracked open the case expecting to see a GSM modem and was surprised to see the cellphone board. It includes a battery backup, and has been soldered directly to the cables which interface with the main PCB using some SIL connectors. Those solder joints were done by hand directly to the pins of the SIM card slot and as well as all of the other important connection points.

26 thoughts on “GSM To Landline Box Has A Creatively Soldered Cellphone Inside

    1. This type of design can inherit FCC compliance, if the cellular board used already had it on it’s own without a case. That is actually how computer shops and manufacturers do things legally with wifi and bluetooth. Wifi and bluetooth boards are normally certified at the board level, without the case.

      1. No, it cannot “inherit” FCC compliance. Because the case is not the original one, the shielding will be different than the originally tested and certified device. Additional wiring and a completely unshielded enclosure mean this hack is unlikely to pass emissions testing. That may be the reason there’s no manufacturer name on the case.

        Another example of “Quality Chinese Engineering”.

      2. Ka1axy is right. They changed the tested product, plus the phone didn’t have a modular approval for inclusion in another device. That being said, I think this is genius. The phone seems securely attached. The connections to the rest of the circuit solid and although appearing crude (DIP packages) the other board looks reasonably well made in an inexpensive-to-manufacture process. It may look unconventional but I don’t see anything to indicate it’s a complete piece of crap.

        1. Perhaps my comment was unclear. I didn’t mean that it always would, but was just not coming up with the wording for modular design. Of course if the original phone was tested WITH it’s case, it would have to have it’s case on inside this product to keep the approval.

  1. I worked for a concrete company a while back and I had to remotely monitor and manage 3 remote gas pumps. The fuel pumps had a modem on board to connect to a POTS for monitoring and management. I bought 3 cellular devices that allowed the fuel pumps to connect to the cell network via their modems. One of them failed and when I opened it up, it was an old Kyocera phone without a case, just like in the article, that supplied the cellular communications.. Pretty slick little box.

  2. I can think of a couple cool ideas for use if I could locate one that is 3g/4g compatible and perhaps can run android/linux.. can you say free international call gateway..
    I have been contemplating building one myself.

  3. I’m doing the same with Alarm Dialers and Alarm Loggers,although nothing commercially yet.

    It is just cheaper than doing anything else considering that old cellphones can be recycled like that and offer all these for 1$ per unit.

    Even new cellphones in bulk sale will go for less than custom making similar circuits.

    FCC Compliance? The only compliance it needs and has is that it gets your job done without ripping your butt off on the price as if it included custom and patended circuits.

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