When TrackerShack set up shop in 2004 listening devices were most usually small transmitters, the most basic of which had a range of a few hundred yards and were picked up on a standard FM radio.
They often had a battery life of about a day and transmitted at full power all the time. Disadvantages included the fact that anyone else within range could also listen in on their FM radio! Such transmitters were illegal then and remain so today, and have largely been replaced by GSM bugs.
GSM Trackers and Bugs were how TrackerShack came about. Using circuit boards from Nokia 5110 and similar mobile phones, TrackerShack created GSM Trackers (worked by triangulating mobile phone masts – not very accurate but this was outweighed by their low cost) and more relevant to this article GSM Bugs.
A GSM bug is a listening device which uses the mobile phone networks. The bug is battery powered and waits in standby mode (just like a mobile phone) until a call is made to it. It then answers the call, without making a noise, allowing the caller to listen in around it. Also like a mobile, the GSM bug listening device has a SIM card in it, this is the number you call to listen in to your bug and spy. These GSM bugs had several major advantages over the old transmitting bugs:
- Legal transmission
- Longer battery life
- Only the person with the phone number of the SIM in the GSM Bug could listen in
However they were larger. This typical GSM Tracker Bug manufactured by TrackerShack measured 13 x 6.5 x 3 cm.
The battery life would be about two weeks of standby, which was shortened with average calling in times to a useful life of about a week. On this model, where the batteries are outside of the case, a 3 x AA battery holder is attached. A larger 3 x D size battery holder could be added, giving a battery life of 2 months plus! In addition, the GSM Bug could be hardwired into a car using a special 12 volt adapter lead.
The microphone on this model was at the end of 1 metre of mic cable, so that the bug could be hidden well away, just the tip of the mic needed to point into the room or car cabin. Other variants of this model had the battery pack and mic built in, so the GSM Bug was just a compact black box.
At peak of production, TrackerShack was buying in Nokia 5110s in pallet loads of 1,000 to meet production demand.
More recently, GSM Bugs have become available from far shores which are smaller, rechargeable and with extra features such as the ability to call you when conversation is detected. Such GSM listening devices are available in our Amazon Spy Shop but note the comments about reliability!
For longer term deployment with guaranteed reliability and performance consider our GSM Double Adapter Plug Bug.