Today we would like to share a review post by one of our European customers. We at Jammer Master are proud of our high-quality signal jammer. It’s what we build our reputations based on. Let’s look at what our customers are saying about us.

Cell phone jammer review

Having several years of experience with these devices, I can have a more or less objective opinion on the subject. I got my first signal jammer around 2020; this model is still on sale today.

Several types of models should be distinguished, depending on their type of power supply:

  • portable jammers operate on an internal rechargeable battery.
  • mains operated jammers.

As well as by their covered frequency ranges: GSM, CDMA, 3G, DCS…

I will voluntarily not deal with GPS jammers, but the overall operation is the same; it is a question of transmitting on the same frequency as the network that one wishes to jam to prevent good reception (and transmission ).

The most common model, by far, is this one, the original packaging with a plug converter in addition:

signal jammer

This model is given to jam the following networks: GSM/CDMA/DCS/PHS/3G.

A few general remarks on this model:


Very long to load and quite fast to unload. For the first models, I counted one night of charging for one hour of operation the next day. Likewise, it would self-discharge fairly quickly if not in use. Also, there was no way to tell when the charge was complete.

On more recent models, all these faults have been corrected, you have to wait for the diode to go out to know that the charge is complete, and the jammer no longer seems to discharge itself over time.

Efficiency and reach

It is very variable; some people are disappointed; because they expect too much. Here is what it is, in my opinion. Generally and logically, the stronger the network where you are located, the harder it will be to interfere with the signal.

Outdoors: My jammer can reach up to 20 meters per the product description, and I think this figure is correct.

Indoors: it all depends on the structure of the building and the strength of the signal it lets through. I had good results in supermarkets, for example.

In public transport: everything also depends on the strength of the signal at time T; I had excellent results in trains and buses.

And the range in figures, in all this?

The best range I have obtained from JM009 is around 20 meters. Another jammer from another supplier is about 7 meters.

The addition of an antenna significantly improves the range (around 30% more range)…

I tested two types of antennas, with a preference for the second, not in terms of efficiency but discretion.

Changing the battery to a slightly punchier one, while still within reasonable limits, should also improve range and autonomy.

In addition, a charger will be needed to provide sufficient voltage (therefore higher than the voltage of the battery in question).

Not having compared the circuits, I rely only on what I have read and tested. It seems similar to the first, but from my experience, the first jammer, JM009, seemed more effective.

At the beginning of 2022, I received and briefly tested a new model, called JM014, which has the particularity of blocking 5G as well, and which covers the following frequencies:

  • CDMA 850-894MHz
  • 5G 1427-4200MHz
  • Wifi 2.4 and 5GMHz
  • GPS L1 – L5 1170-1580MHz
  • Remote control 315MHz

You can tell by these specs it’s a very powerful jammer that even can block 5G.

signal blocker

The bottom line

Jammer Master is professional signal jammer supplier. If you are interested in our product, please check it our in our webshop, we are currently offering free worldwide shipping and one year warranty. Buy it today!

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