Like mobile phones, most mobile broadband routers are considered plug and play where you just insert your SIM card and it’s ready to use. However, in some instances routers and modems will need some further tweaking to improve the connection stability or to even get online.
This guide is broken down into several parts, starting with troubleshooting steps that apply to all providers. Outdoor antenna troubleshooting can be found further down the page.
Poor indoor reception, even near a window
Most modern glass including replacement glass has a ‘Low-E’ coating to minimise the amount of infrared heat escaping outside through the glass, in improving energy efficiency. A side-effect is that this coating is also very effective at blocking radio signals covering all the cellular bands. As a result, the glass effectively acts like a sheet of metal to any wireless device placed next to it.
Some modern homes also have foil-backed insulation in the walls, which also blocks the cellular signals penetrating the walls. Similarly, this also applies when foil insulation is used in the loft, resulting in poor reception in the loft.
Try placing the device between two panes of glass, particularly in a bay window (if any) where the glass panes meet at various angles. There is good chance the frame of the window is not foil insulated, allowing the signal to pass through.
Unfortunately, if every part of the house is well insulated with foil-backed or low emissivity coatings, the only option would be to get an outdoor antenna.
Poor indoor reception with external antenna
As with using the router’s own antennas, the signal may be blocked or greatly reduced by the window’s ‘Low-E’ coating. In this case, placing the antenna in the window or even on the glass (with suction cups), may not provide any improvement to the signal.
Directional antennas set up indoors may provide even worse performance than the router’s own antennas. When the signal passes through the building, it bounces off various items, particularly metal objects and ‘Low-E’ coated glass. Thus, the router’s internal antenna may be picking up some of the reflected signals that the directional antenna would not pick up.
If an antenna needs to be used indoors, such as due to building restrictions or renting, choose an omni-directional antenna. Mount it as high up as possible, preferably in the loft.
Network search shows 4G network, but will not register
With most desktop routers and especially outdoor antennas, the device will likely pick up 4G cell towers that are outside the range limit of the device. While GSM (2G) signals have a 35km hard limit, the range limit of 4G can set by the mobile operator. Once outside of the range limit, the device will not be able register with the mast regardless of the signal strength as the range is determined based on the round-trip delay, i.e. how long it takes for the signal to travel to the cell tower and back.
Three & iD Mobile: The Three network goes a step further by limiting the range based on the type of device, which can be particularly problematic across bays, lakes or flatland. If a phone gets a 4G signal on Three, but not the modem or router, then there is a very good chance the device is outside of Three’s range limit for data devices. In this case, try testing the device in another area with strong 4G coverage to rule out a fault with the device. If using an outdoor directional antenna, try aiming various directions as it may be aimed at a distance 4G cell tower or even picking up a reflection of the near-by cell-tower.
Vodafone will not go into 4G mode
With a new prepay SIM, it can take 24 hours before the SIM can use the 4G network after its first use. The SIM may also need to be registered with My Vodafone. If the SIM will still only go into 3G/HSPA mode, try contacting Vodafone as they may need to re-activate the account for 4G. I had to get 4G reactivated with my prepay phone a few times already. I have also heard of other people that had to contact Vodafone to reactivate 4G access again even with their prepay Vodafone broadband.
iD Mobile will not go into 4G mode
Unlike Three SIMs, an iD Mobile SIM needs to connect to the network in 3G mode first before it can hand over to 4G mode. This can take up to 10 minutes after connecting in 3G mode. If the device remains in 3G mode after 10 minutes, restart the device or temporarily set the network mode to 4G-only (if available). Do not leave the device in forced 4G mode as it will not be able to reconnect if the connection drops or if the device is restarted.
iD Mobile cannot be used with 4G only devices such as outdoor LTE routers that do not support 3G mode.
Meteor will not go into 4G mode
While Meteor prepay phone SIMs will work in modems and routers, the SIM must be set up on a €20 or €30 Simplicity plan to connect in 4G mode. The €20 simplicity plan gobbles up €20 of credit each month and provides 15GB of data. All the other prepay phone plans including the €10 simplicity plan cannot access the 4G network.
Meteor’s prepay mobile broadband SIM provides 4G access, whether a bundle is purchased. For example, it can connect in 4G mode even to bring up the “out of data” landing page.
Meteor gets no signal anywhere (prepay)
The SIM may have been deactivated, particularly with light usage. If the SIM has not been topped up in 6 months, the SIM is deactivated. This 6 month period coincides with the length of the 180 day pass. To reactivate, a €10+ top-up is necessary (voucher or online banking) and then contact Meteor’s support to reactivate the SIM. If a 180 day pass is approaching its expiry date, top it up by €30 before it expires and then purchase a new pass once the existing one runs out.
3G connection Intermittently drops
If the device is 4G capable, there is a good chance the device is picking up a 4G cell tower that is outside of the range limit as explained above. If the device tries connecting to such a 4G mast, it will lose the connection as it unsuccessfully attempts to hand over to the 4G mast. To prevent this happening, set the device’s network mode to ‘3G only’ or turn off ‘Enable LTE support’, depending on the device/model.
If near a bay, lake or even high up a hill, another possibility is that the device is picking up a stronger signal from a further away cell tower that is out of range, particularly if the nearby one is obstructed in some way such as behind a hill, trees or is also across the water. In this case, try repositioning the device in different areas, even of the same room as this may help attenuate the unwanted signal. It may be necessary to get an outdoor directional antenna, which would also attenuate the unwanted signal.
Check the APN setting is correct. For example, if a broadband APN is used with a Meteor phone SIM, it will result in an intermittent connection. Similarly, if there is a typo in the APN name.
SIM works in phone, but not in the modem/router
First, double-check the APN is connect or retype it in. Most routers automatically configure the APN based on the inserted SIM, so if the APN was configured before the SIM was inserted, it may have picked up an incorrect APN, especially if a phone SIM is placed in the router.
Try setting the device to 3G-only mode or turn off the ‘Enable LTE’ setting temporarily, especially with the Three network. The device may be trying to register with a 4G network that is outside its range limit as explained above. With the Three network, the 4G range limit can be shorter for modems and routers than it is for phones and Three is known to reduce the range limit of masts it upgrades.
Note that Lyca mobile actively blocks tethering on its network, so its SIMs will unlikely work in a router either.
While the right antenna can do wonders for the signal strength and speed, it can lead to additional issues or even no connectivity at all! The first thing to check is that the antenna leads are properly connected and that the router is configured to use the external antennas if there is such a setting.
Before carrying out any performance troubleshooting, first check that the issue is not purely down to high contention, i.e. try running speed tests in the early hours of the morning.
Apart from surveying the area for alternative less congested masts at peak time, the following troubleshooting tips should only be carried during off-peak periods such as early on a weekday. This is especially important with the Three network which faces high to severe contention in the evenings.
Modem/router will not connect with outdoor omni-directional antenna
If the device can connect to 4G with its internal antennas only, it is quite possible that the outdoor antenna is picking up a stronger signal from a mast outside of the range limit, in which case the device will keep unsuccessfully trying to connect to it, ignoring the nearer mast that may be obstructed by a hill / trees. First try swapping the two antenna leads as it may pick up a stronger signal on the nearby mast on the opposite polarity.
If swapping the cables does not work, try temporarily placing the antenna on each side of the house (e.g. using a DSLR camera tripod). With the side that works and provides the strongest signal reading, mount it on that side / gable, ensuring it is obstructed by the wall/building in the opposite direction. This way the unwanted signal is attenuated by the house.
If lowering the antenna height obstructs the line of sight or results in little improvement over the router’s internal antenna, then a directional antenna is required to mount it at a height. This will provide better gain over the omni-directional antenna for the wanted signal, while also attenuating the signal of unwanted masts in other directions.
Unsatisfactory download performance with outdoor omni-directional antenna
Omni-directional antennas are only truly omni-directional for its vertical polarity element. The horizontal element is sensitive to the direction it faces, just like a horizontally positioned FM radio antenna. Try turning the antenna left/right by 30 degrees to aim its horizontal polarity element and rerunning the speed test. Repeat until you achieve the highest consistent speed.
If the performance remains like the router’s built-in antenna, the mast may be congested, in which case a stronger signal will not provide any additional speed. Try comparing the performance against the router’s internal antennas early in the morning such as before 8am.
If the performance is worse, the antenna may be picking up a stronger signal from a more congested cell tower than what the router’s internal antenna was picking up. In this case, it would be worth taking down the antenna and trying it temporarily on each side of the house such as with the help of a DSLR camera tripod and rerunning the speed tests, then mount the antenna on the wall/gable on the side that provided the best performance.
Modem/router will not connect with outdoor directional antenna
If the device connects fine with its internal antennas, but not with the outdoor antenna, first try swapping the two leads to rule out a break in one of the cables. Many routers establish the connection over antenna port #1, so if this antenna lead has a break, swapping over to the second lead may provide connectivity, although degraded due to the lack of the second antenna connection.
Is the antenna band specific? Some patch antennas only pick up a specific band such as LTE band 20 (800MHz), 3 (1800MHz) or 7 (2600MHz). Yagi antennas are similar. For example, a Colinear LTE antenna pair typically only covers 1700MHz to 2700MHz and this will not work on LTE band 800MHz or the 900MHz 3G band. Similarly an LTE band 3 patch antenna will not work on LTE band 20 or vice versa. Most LOG antennas (triangle shape) are wideband and generally cover all the LTE bands between 800MHz and 2700MHz.
The higher frequency bands such as LTE band 3 (1800MHz) and the 2100MHz 3G band are typically used in built-up areas such as large towns. Rural areas are mainly covered by LTE band 20 (800MHz) and the 900MHz 3G band, which propagates and penetrates a lot further than higher frequency signals.
Even with clear line of sight with a cell tower operating on a higher LTE band, that transmitter could be outside of its configured range limited, determined by the round trip delay between the device and the transmitter. This is more common with multi-carrier transmitters where it hands over nearby devices to a high frequency band such as LTE band 3 which typically provides higher bandwidth and further away devices to the lower frequency such as LTE band 20 which propagates further.
If LTE coverage was lost after a cell tower upgrade, the upgrade may be providing multi-carrier support (4G+ / LTE Advanced support), in which case the cell tower likely also enforces range limits based on the LTE band. In this case, a user that was using the high frequency band (e.g. LTE band 3 on Three) is now outside the allowed distance limit, in which case an LTE band 20 or wide band antenna is required to connect.
Unsatisfactory download performance with outdoor directional antenna
If the performance remains like the router’s built-in antenna, the mast it is aimed at may be congested, in which case a stronger signal will not provide any additional speed from that mast. If the antenna can freely swing direction without facing the wall or other obstacles, try aiming the antenna at alternative masts, including 3G masts. In many areas facing network congestion, many of the 3G masts in the area may have little congestion, especially with the Three network as most people let their routers automatically go into 4G mode. A good directional antenna can take advantage of this by letting the user connect to any 3G mast within range, which may be substantially faster than the 4G mast during peak time.
Try adjusting the antenna’s angle of elevation, especially if the cell tower is located on a hill. A few degrees of elevation can make a significant difference, particularly if the building is in a valley.
Try also turning the antenna left or right by a few degrees, even if it results in a slight dip in the signal strength. The antenna may be picking interference near the direction of the mast, such as from another mast operating on the same frequency further off, such as across a bay or lake.
If the antenna is a panel/patch antenna mounted vertically, try mounting it horizontally. This can have a significant effect on its performance, particularly with fringe reception.
If the antenna consists of two separate antennas, these must be mounted in opposite polarities, one vertically and the other horizontally. Try also separating them further apart. The two antennas can be mounted on separate poles, which will also improve the performance with fringe reception. I have mine roughly 2m (6 feet) apart, so they don’t need to be right next to each other either.
To adjust one antenna at a time to optimise its performance, connect just that one antenna to port #1 of the modem/router. Once optimised, disconnect that antenna and connect the other antenna to port #1 to adjust it. Finally connect both antenna cables.
Unsatisfactory upload performance with external antenna
Most modems and routers use port #1 for uploading. In 3G mode, only port #1 is used for uploading, while port #2 is used for diversity. Depending on the signal strength / quality of each polarity, the uplink performance can vary significantly between the two polarities.
Try running a few speed tests, then swap the two antenna cables and rerun the speed tests. If one lead configuration provides greater upload performance, leave it in that configuration.
The signal strength also has a greater impact on the upload performance than it does for the download performance. Increasing the antenna elevation will generally help.
Router will not boot or power up properly
The power supply may have failed. In most instances where I experienced a failed power supply, it provides just enough power to light and LED or two of the router, giving a false impression that the router has a firmware or boot issue.
Check the voltage and amp rating of the router or of the existing power supply and try another power supply of the same voltage and at lease the amp rating mentioned. Many routers such as Huawei routers use a 12V 2A power supply. Do not attempt to connect a power supply with a higher voltage rating as the higher voltage will damage the router.
Meteor / Eir Mobile Broadband usage
You can check your remaining allowance by sending the SMS ‘balance data’ to 50104 from the router web interface. This also works for Meteor prepay broadband.
The following steps are based on the Huawei B315 router, which Eir has been supplying with its 4G broadband contract:
- In your web browser, go to http://192.168.1.1/
- Go into the ‘SMS’ menu.
- The default username and password are both admin.
- For the recipient, enter: 50104
- For the message, enter: balance data
- Send the message and the check the message that comes back.
This works even without registering for My Eir or MyMeteor. As the router stores the messages on the SIM card, be sure to delete the messages afterwards.