In this review we are going to tell you about the results of the stress test of a Nokia N97. This is a side slide phone with a QWERTY keyboard, a resistive touchscreen and a LI-pol battery with 1500 мјh capacity. The handset is made of plastic, the edges on the front side are nade of metal. This combination is common for present-day cell phones. The box has a minimal design (pic.1). It is made of a matted material on which the  picture of a Nokia N97 is engraved. We were delighted when we opened the box. The delivery set includes a handsfree, a charger, a CD, a manual, a USB-cable which is longer than the other “Nokia” USB-cables, a duster for the screen and a connector adapter for a micro-USB port which is going to be common for all handsets since 2011 (pic.2). We were very glad to see all these useful things in one box.

The results
Nokia N97 has a classic design (pic. 3,4). The front panel is simple but smart. You can see individuality of the phone only if you open the clamshell.

1. The stress test of the Nokia N97. Stage 1 — Ability to withstand light shocks

1.1 Drop-down

When we examined the Nokia N97 we made an assumption that the clamshell was prone to fatigue or failure and the phone could be broken into two parts if we dropped it down. So we practised it. We sequentially dropped the phone down onto each face, edge and corner from 1m on the carpet (video 1) and from 30 cm on the ceramic tiles (video 2). Sometimes the he back cover shifted when the phone hit the carpet and the tiles. Once when it hit the carpet the clamshell opened but it did not damage the handset.

Video 1. Drop-down on the carpet from 1m

The grade is 30 from 30 possible.

Video 2. Drop-down on the tiles from 30cm

The grade is 30 from 30 possible.

1.2 Ability to withstand squeezing

Nobody really wants to step on or sit down on a chair with such an expensive mobile phone as Nokia N97 in the back pocket. But we did almost the same. We simulated the squeezing by placing 3kg plank on it (pic.5). The back cover of the handset is not smooth. It has 2 projections which carried all the load. In spite of this the phone passed the test with no problem.

The grade is 24 from 24 possible.

1.3 Bend test

This test is similar to the previous. We simulated the situation when a person lies or sits down with a phone in their trouser pocket. Actually we placed the device between the two supports and hitched a rope with a load of 1kg over it (pic.6). No wonder that this slide phone was not bended at all. The Nokia N97 passed the stress test well.

The grade is 24 from 24 possible.

1.4 Deterioration

Everybody knows how a handset can look if it is constantly kept with other small, sharp and hard things in a pocket. We decided to look at the Nokia N97 after a negligent treatment for some time. We put this device into a cylinder of a centrifuge together with some keys, coins and plastic balls. The centrifuge rotated the cylinder at the speed of 500 rpm. The stress test lasted for 5 min (video 3). The result: the metallic part of the phone got some scuffs and small scratches (pic.7). The plastic part of the phone was less damaged. We saw only some tiny scratches on it.

Video 3. The rotation of the centrifuge

The grade is 10 from 15 possible.

1.5 Quality of the material of which the phone is made

We decided to check the material quality of the phone by scratching the screen and the back cover with a nail at the force of 100g (video 4,5). We failed to make any scratch on the touchscreen but we managed to make a small one on the back cover. However the scratch was not deep at all and the matted cover of the panel made it unnoticeable.

Video 4. Scratching the display

Video 5. Scratching the back cover

The display gets 15 from 15 possible

The back cover gets 15 from 15 possible

1.6 Hot temperature

We discovered the reaction of the Nokia N97 to a hot temperature. Sometimes people leave their mobile phones in the sun and it has a bad impact on the handsets. We feared that hot temperature could damage a flexible touchscreen of our Nokia N97 as it did not have a glass base under it. Actually we put the phone under a 40Wt lamp which were heating it up for 3 min.(video 6). The result was quite predictable. As the majority of  “Nokia” touch phones the N97 passed the test succesfully.

Video 6. Hot temperature test

The grade is 12 from 12 possible.

1.7 Dust resistance test

Dust is one of the worst enemies for electronics. It can not only spoil the look of the phone but it also increases the risk of the clamshell deterioration. Dust also penetrates in the gaps between keys and breaks them. In order to check the ability of the Nokia N97 to resist dust we put it inside a box which was full of dust taken from a vacuum cleaner.  We were shaking the box with the phone inside for 2 min.

We discovered that the front and the back panel of the handset are strongly attached to each other. It protected the keyboard because we found almost no dust in it (pic.8). The USB-port has no peg. But there was not much dust inside it (pic.9). In comparison with the cell phones which had the pegs in their USB the Nokia N97 port passed this test better. We were surprised when we saw very little dust under the back cover (pic.10). We easily cleaned all the dust but we could not get to the clamshell unfortunately and some dust was still inside. The keys operated well and the ring sound was OK.

The grade is 12 from 12 possible.

1.8 Communication quality

Signal reception is one of the most important features of any mobile phone. So we decided to test it. We put the Nokia N97  into a shielded box with 40×50mm hole (video 7). Then we made a call to the Nokia N97. At first the indicator showed that the signal reception fell by 2 points. Then the communication quality was normal again. After this the phone received all the calls with no problem. Sometimes the signal reception fell by 1 point.

Video 7. Communication quality test

The grade is 15 from 15 possible.

All in all for the 1st stage of the stress test the Nokia N97 gets 187 points from possible 192.

2. The stress test of the Nokia N97. Stage 2 — Tougher conditions

2.1 Drop-down

This time the height of the drop-down on the carpet was 1,5 m and the height of the drop-down on the tiles was 50cm (video 8, 9). The result was similar to the previous stress test. But this time some small dents appeared on the metallic part of the handset (pic.11) and one of the edges twisted a bit.

Video 8. Drop-down on the carpet from 1,5m

Video 9. Drop-down on the tiles from 50cm

The grade for the drop-down on the carpet is 30 from possible 30.

The grade for the drop-down on the tiles is 30 from possible 30.

2.2 Ability to withstand squeezing

In the 2nd stage we squeezed the phone by putting a 10kg plank on it. The result was the same as in the 1st stage: no deformation, no creaks. The phone passed this test well.

The grade is 24 from 24 possible.

2.3 Bend test

We increased the weight of the load on the rope from 1kg to 5kg. We saw a significant bend which is no wonder for slide cell phones in such situations.

The grade is 24 from 24 possible.

2.4 Deterioration

We increased the time of this stress test to 10min. After the test we noticed some scuffs and scratches on the metallic part of the Nokia N97 (pic.12) and some small droplets on the screen (pic.13). But when the lighting was on these droplets were unnoticeable. The plastic cover of the corners of the Nokia N97 got some scuffs (pic14).

The grade is 10 from 15 possible.

2.5 Quality of the material which the phone is made of

When we increased the force of pressing the nail at the screen to 300 g we still failed to make a scratch. We only managed to make a scratch on the back cover but it was not deep at all and the matted cover made it hardly noticeable.

The display gets 15 from 15 possible.

The back cover gets 15 from 15 possible.

2.6 Cold temperature

Cold and frosty winters can be too harmful for mobile phones. Cold temperature may have a bad impact on the work of any gadget. It can shorten its battery life. In order to check the performance of the Nokia N97 in low temperatures we put it into a freezer for 2 hours. All this time the handset was in a speaking mode. The temperature in the freezer was from -15 to -20. When the time of the stress test was over we took the Nokia N97 out and checked its state (video 10). It was surprising but the battery was full. This is a very good result for such a test. The image on the screen hung up a bit but after we warmed the device up to a room temperature it operated perfectly.

Video 10. The cell phone after the test in the freezer

The grade is 18 from 18 possible.

2.7 High temperature

We increased the time of the test to 5 min. (video11). Though the metallic part was very hot overheating did not cause any damage.

Video 11. High temperature test

The grade is 12 from 12 possible.

2.8 Water resistance test

No doubt that liquid is the worst enemy for a mobile phone. In this stress test we dunked our gadget under water for 1 second (video 12).

Nothing bad happened to the Nokia N97 (pic.15). The electronic components were not damaged. But much water penetrated under the battery (pic.16). The USB-port was also full of water (pic.17).

After this test we dried the handset with warm air.

Video 12. Immersion in water for a sec

The grade is 30 from 30 possible.

2.9 Dust resistance test

This time we put the phone into the box with dust again and then we were shaking it for 5min. There was so much dust inside the clamshell that we could not close it thoroughly (pic.18). It was very difficult to get rid of the dust. We heard an extraneous noise when the Nokia N97 rang. It was caused by the dust inside the loudspeaker (pic.20). There was as much dust under the back cover as in the previous stress test.

2.10 Communication quality

In order to create worse conditions for the Nokia N97 signal reception we decreased the diameter of the hole in the shielded box to 20×20mm (video 13). The indicator showed different result all the time. During the incoming calls the signal reception was better than when the phone was in a waiting mode. The handset received all the calls.

Video 13. Signal reception test

The grade is 15 from 15 possible

All in all for the 2nd stage of the stress test the Nokia N97 gets 231 points from possible 240.

3. The stress test of the Nokia N97. Stage 3 — The toughest conditions

3.1 Drop-down

At the last stage of this stress test we increased the height of the drop-down on the carpet from 1,5 m to 2 m and we also dropped it from 1m on the tiles (video 15). In both cases the back cover and the battery fell out. When the Nokia N97 hit the tiles a small piece of plastic broke off the handset. The phone was damaged but in comparison with what we had already got it was insignificant. The Nokia N97 operated well anyway.

Video 14. Drop-down on the carpet from 2m

The grade is 30 from 30 possible.

Video 15. Drop-down on the tiles from 1m

The grade is 20 from 30 possible.

3.2 Ability to withstand squeezing

This time we placed a 20 kg plank on the Nokia N97. The part near the camera squeezed a bit. But it did not cause any damage. The handset survived and functioned well.

The grade is 24 from 24 possible.

3.3 Bend test

In this stress test we increased the weight of the load on the rope to 10kg. It is always difficult to bend slide cell phone and our Nokia N97 is not an exception. Though we managed to make a small bend it did not deform the handset.

The grade is 24 from 24 possible.

3.4 Deterioration

The time of this experiment was 20 min. The result: there appeared some long and deep scratches at the metallic edges (pic.23). The sputtering of the plastic rim of the keyboard was damaged (pic.24).  More droplets appeared on the display (pic.25). We could see them only if the lighting of the screen was off. The picture on the display was good enough. In this test there was something that we had not expected to see Ц the shutter of the lens opened and the camera glass was broken (pic.26).

The grade is 10 from 15 possible

3.5 Quality of the material of which the phone is made

We discovered how the Nokia N97 could be changed if we doubled the force of scratching (600g). This time the scratch that we have made was quite noticeable (pic.27). It was not very deep but it distorted the picture on the screen. The scratch on the back cover was deeper than in the 2nd stage of the stress test. But we can’t say that it made the handset ugly.

Video 16. Scratching the screen

10 points (from 15 possible) for the screen

15 points (from 15 possible) for the back cover

3.6 High temperature

This time the stress test was carried out for 10 min. (video 17). In the result most of the screen blackened. Some minutes later its color rendition became normal again. Unfortunately the Nokia N97 did not fully survive in this test. The reset and call buttons did not work. You will find the reason of such a fail in 3.13 (disassembling).

Video 17. The last high temperature test in this review

The grade is 8 from 12 possible

3.7 Water resistance test

1 second was not enough for water to damage the Nokia N97. We decided to find out what would happen if we dunked it under water for 20 sec. (video 18). At first look nothing bad had happened. But when we examined it thoroughly we understood that much water penetrated under the battery (pic.29). Small copper parts of the board oxidized. When we dried the gadget for an hour we examined it once again it operated perfectly.

Video 18. Immersion in water for 20 sec

The grade is 30 from 30 possible.

3.8 Immersion in beer

When we carry out stress tests of different cell phones we always try to simulate real life situations. This time we made a very tough test which could be fatal for any gadget Ц we dunked the Nokia N97 under the most popular alcoholic drink in the world. The phone was under beer for 10sec (video 19).

As the majority of Nokia cell phones with the sockets for 3,5mm jackplugs the N97 showed the connection with the handsfree.

It was surprising but the phone survived in spite of the fact that a lot of water penetrated under the battery (pic.30). All the buttons functioned well. The port was not oxidized. After the test we rinsed the device with flow water and dried it.

Video 19. Immersion in beer

The grade is 9 from 9 possible.

3.9 Dust resistance test

The previous dust test proved that this cell phone is not dust resistant. In spite of this we increased the time of the centrifuge rotation to 10 min.

The result was almost the same as in the previous dust resistance test. The main difference was the loudspeaker – it was full of dust and mud (pic.31).

We could get rid of the dust only with the help of a needle. We heard a loud extraneous noise when the phone rang.

The grade is 8 from 12 possible

3.10 The keyboard

At this stage we would like to present you a review of the keyboard and some additional keys of the Nokia N97.

The push-button is connected to the ribbon cable. It is easy to replace it if it breaks down. But this type of a button can be easily damaged by liquid. Fortunately the plastic upper part of the button is deeply installed in the handset. This design protects it from liquid.

QWERTY keyboard of a Nokia N97 has no design innovations. It is common for all present-day cell phones.

The reset and call buttons which did not pass the high temperature test are connected to the touchscreen. The heat probably deformed the touchscreen and damaged its current-carrying tracks. That was the reason why these buttons stopped functioning.

The grade is 30 from 30 possible

3.11 Communication quality

We decreased the diameter of the hole in the shielded box to 15×15 mm (video 20). At first the indicator of signal reception displayed only two points. But when we made a call the signal reception became better. The Nokia N97 received all 10 calls. This is a very good result in comparison with the other handsets that we had tested before.

Video 20. Communication quality test

3.12. Electric overloads

At the end of the stress test we decided to discover how the Nokia N97 could survive electric overloads. At first we made a short circuit of the charger (video 21).

As you can judge by the video the short circuit did not stop the charging of the phone. The charger survived, the cell phone operated well.

Video 21. Short circuit of the charger

The charger gets 15 points from 15 possible

Secondly we made a short circuit of the battery in order to check how its quality. The battery is provided with the special system that protected it from being immediately discharged in case of a short circuit. We closed the power supply terminals and with the help of a pincers. Video 22 shows that the phone operated well and the battery was full all the time.

Video 22. Short circuit of the battery

The battery gets 15 points from 15 possible

In order to find out the power supply extremes we connected the phone to the controllable power supply and set the nominal voltage (5volts). Then we started decreasing the voltage to its minimum (until the charging was stopped) and then increasing the voltage to 8 volts (video23).

When we decreased the voltage supply to 0 volts we saw that the phone continued charging. It was the phoneТs glitch. Even when we disconnected the handset from the controllable power supply we saw the same the indicator showed that the phone was being charged. We suppose that not all Nokia N97 cell phones have such a glitch. We carried out this test after the phone  had had a lot of other troubles and this accident could be caused by other factors (e.g. water, beer, dust etc.).

The result of the voltage supply increase was not also good. When the voltage supply was about 8volts the handset stopped charging without any notice. We only received a reminder that the controllable power supply should be unplugged in order to save energy.

Video 23. Increase and decrease of the charging power supply

For the ability to operate with the lack of voltage supply the handset gets 10 points from 15 possible.

In order to find out how the Nokia N97 could pass the overcharging test we took out the battery and used the controllable power supply instead of it (video24). When we increased the voltage of charging to 7volts nothing bad happened. But when we were gradually decreasing the voltage supply the brightness of the screen was decreasing respectively.

Video 24. Overcharging test

The grade for the overcharging test is 15 from possible 15.

3.13 Disassembling, build quality

It was quite easy to disassemble and to assemble the Nokia N97. We saw nothing new inside the phone (pic.32): the same old resistive sensor, the board which occupied most of the handset (pic.33). We did not find any metallic element which could make the phone more rigid. But it was not necessary because the handset itself was rigid. It’s hard to break it by dropping down and bending. The clamshell ( pic.32 in the lower right corner) is made of plastic and not of metal as one may think looking at the picture. However this plastic has a metallic sputter. The clamshell shields the board and acquits the phone of using heavy metallic screens.

To tell you the truth the Nokia N97 has one very weak point. Look at the ribbon cable (piс.34). A hillock-type defect appeared on it because there was a lot of dust and mud inside the clamshell. Well, the  ribbon cable deterioration is a problem of all the slide cell phones. You should remember it when you decide to buy such a handset.

The grade is 20 from 20 possible.

All in all for the 3rd stage of the stress test the Nokia N97 gets 308 points from possible 351.

Conclusion:

The Nokia N97 cell phone surprised us greatly. It successfully passed the tests which we thought would be fatal for the phone (drop-down, immersion in water and beer) and it failed where we did not expect it to fail (Уkeeping in a pocket for a long timeФ, hot temperature test, overvoltage of the charger).

The clamshell was not  prone to fatigue or failure as it might seem. It was opened when we dropped the phone down but the handset was not damaged at all.

Among the advantages of the gadget we may mention the battery, because it was full (according to the indicator) after all the tests (after the phone spent 2 hours in the freezer in the speaking mode, after the immersion in water and beer etc.).

The appearance of the Nokia N97 after the stress test (piс.35, 36).

All in all the phone gets 726 points from possible 783

According to 100-rating scale the Nokia N97 gets 93

The stress test of the Nokia N97, 10.0 out of 10 based on 3 ratings