Thermal camera teardown - EEV/E2V ARGUS 2 Firefighter Camera by Fraser

[Fraser]

Bruno28,

Yes you have the classic sticky Iris symptoms. The 'grinding' noise is the sound of the Iris drive signal emitted by the motor as it strains to move the Iris leaves. The drive signal is current controlled and current monitored. If the Iris does not move and overcurrent occurs, the warning triangle appears.

The good news is that it is relatively simple to rectify this situation.

1. Remove the two socket head screws that secure the objective lens holder to the lens chassis.
2. Carefully pull the objective lens away from the lens chassis
3. Note the layout of the Iris parts and which Iris leaf is in front, and which is behind.
4, the Iris leaf pivot is sometimes a sliding fit into its hole. It does not need to be removed.
5. Gently lift the two Iris leaves off of the Iris pivot pin and lay them down on clean paper.
6. Inspect the Aluminium surfaces around the Iris slot for any corrosion or debris. Remove any that is found.
7. Using a Q-tip soaked in IPA, clean the surfaces of the Iris leaves to ensure no contaminants remain. Dry the leaves carefully with a soft cloth, ensuring no cloth threads remain in the 'sawtooth' sections against which the motor gear acts.
8. Using a Q-tip soaked in IPA, clean all surfaces of the Aluminium lens chassis that have contact with the Iris leaves.
9. Carefully clean the Iris motor brass gear with IPA to remove any contaminants.
10. Reassemble the Iris leaves onto the Iris pivot, taking note of the centre mark indicator cut into the bottom of the front leaf. The Iris leaves operate symmetrically so need to be assembled as such. Assemble them so that they overlap the sides of the Aluminium chassis equally at the sides, whilst the front leaf centre point marker is centralised and in line with the Iris motor shaft.
This may sound more complex than it is. Have a play with how the Iris works and you will see what is required for correct alignment. I use my fingers to check the over hang of the Iris leaves either side of the Aluminium chassis.
11. Once the Iris leaves are correctly aligned, refit the objective lens holder and secure it with the two socket head screws. The objective lens holder needs to be aligned so that it is laterally centralised.

The Iris service is now complete.

Fraser

[Fraser]

Whilst the camera is open, remove the Raytheon controller PCB to reveal the EEV camera controller that sits below. Examine the area adjacent to the EEV controller board large connector where it is connected ted to the BST sensor board. Towards the left of the connector on the EEV controller board there is a small capacitor that can burn-up. You will see the blackened capacitor if it has failed.

It is also a good idea to remove the EEV controller and inspect the yellow Tantalum capacitors on the reverse side of the board, adjacent to where the viewfinder shell sits. The viewfinder shell can impact one of the capacitors if the camera is dropped, shearing its connections. I have even found that capacitor jammed in the Iris mechanism after it was completely sheared off of the board !

Sorry I am not providing pictures..... they are on my computer that is presently in pieces !

Fraser

[Fraser]

Looking back through the images in this thread I have already highlighted the issue with C19 getting sheared away from the PCB. In pictures of the EEC controller board, the small brown MLC SMD capacitor that can fail is also pictured. It is next to a yellow Tantalum capacitor, adjacent to the board connector. Sadly no component numbers are present. If it has failed, I can look up the value of the capacitor later.

Fraser

[Bruno28]

Thanks Fraser for the detailed instructions. After I manages to move the pinion it worked smoothly.
I wouldn't not want to fiddle any or remove any pcb boards, just in case I damage something and then end up with a camera that doesn't work. It now seems to be working. But I didn't get the iris to operate. Maybe it need a a lot more heat than the window for it to start working? I need to try it wit open flame to see If it works then. 

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[Fraser]

A soldering iron is a good test source for the Iris, just move it into the field of view 30cm from the lens.

No worries on removing the PCB's but use a torch to look for the problems. The unit is VERY rugged and hard to break even when removing boards. You do need the special security screw driver bit though.

If you do not dismantle the Iris and clean it, the sticking problem will re-occur very soon. The pinion sometimes gets stuck on some debris floating inside the camera but it still needs a clean. I found red screw head lock paint in one cameras Iris pinion gear and jammed the Iris. This is very rare though. Most cameras are suffering from lubrication leaching out of the motor and onto the Iris leaves over time. Some have corrosion issues, but they are few thanks to the excellent module sealing. Never ever apply any lubrication to the pinion gear or Iris leaves ! They are designed to operate dry.

Fraser

[Bruno28]

Thanks. I'll try the soldering iron trick.
Is there anything I should visually see? A shift in the cold/hot parts looking darker?

 Because i have already put it all together, So won't be able to see the motor working.

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[Fraser]

You will hear the Iris motor and see correct exposure of the hot object. There should be no re-occurance of the warning triangle.

Fraser

[Bruno28]

I tested with a open flame and it shows signs of working well.

https://youtu.be/8KceTBSAwHg

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[Fraser]

Good news

The ARGUS2 tends to consume Alkaline cells quite quickly. You can use Ni-Mh cells in the AA battery pack but the battery meter will not read correctly. The camera will operate normally in all other ways however.

Fraser

[Bruno28]

Good news

The ARGUS2 tends to consume Alkaline cells quite quickly. You can use Ni-Mh cells in the AA battery pack but the battery meter will not read correctly. The camera will operate normally in all other ways however.

Fraser

I'm using Sanyo eneloop. Which are rechargeable. But the batteries were fully charged. And in about 5-10 mins it had gone down to what you see in the video. It suck the life out of them. Not very efficient.

But at least the camera is working well now. And in that great condition it looks like a kit  for collectors.

Thanks for your help. Also see a thread I started in the thermal section. When I saw this camera I thought of you and how you would like one or probably already have one of those hahah

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[Fraser]

The ARGUS2 does have quite a high current draw. It uses a thermoelectric temperature stabiliser for the sensor. The stabiliser is Peltier based so draws quite a lot of current when active. Initial switch on current is high as a result. The camera also has to power the chopper wheel motor and a current hungry cathode ray tube monitor. IIRC this all adds up to a nominal current draw of around 350mA after initial temperature stabilisation.

Fraser

[Fraser]

I just looked at the ARGUS2 specs.

She originally came with a 1600mAh Rechargeable battery. This was stated as having an operational duration of 2 hours. The power consumption of the camera is stated as nominally 5W. It was apparently one of, if not 'the' lowest power consumption cameras of its time.

Note what I said about using Rechargeable cells in the Alkaline battery pholder. The battery meter becomes pretty meaningless and should be ignored as it's calibration is set for an Alkaline cell discharge curve, not that of Ni-Cad or Ni-Mh. You should get 2 hours run time with a cell if at least 1600mAh capacity.

Also remember, this camera can image temperatures far higher than most standard 'general use' thermal cameras sadly the BST technology does not lend itself to temperature measurement though. Temperature measurement would be either by using a Black Body termperature reference source in the FOV or by using an IR thermometer.

Fraser

[Bruno28]

Ok. So it's misreading. I'll see how long it lasts. It's not a camera I'll use much. But something I do like is the capability of detecting very little heat and also very smooth frame rate. Much higher fps than the thermapp.

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[Fraser]

If you connect the ARGUS 2 to a decent sized external monitor you will see a far more detailed image than that produced by the internal CRT monitor. The internal monitor seems to produce a soft edged image even when correctly focussed.

The down side is that you may notice the odd dead pixel that has occurred over the years since manufacture. Not a fault though so best to just ignore them ! There may be no dead pixels visible if your sensor has been treated kindly.

Remember that the video output standard is set in hardware to either PAL or NTSC, depending upon what was ordered. Some older monitors need the right standard input, whilst others auto switch between standards. My 19" CCTV LCD monitors are fully automatic in this respect and produce a lovely image from the ARGUS cameras. I have also used cheap USB video frame grabber / DVR dongles with these cameras. I provided test images with all of the ARGUS 2's that I repaired using this method as it is far better than taking photographs of the magnified internal monitor. The ARGUS2 uses a BST sensor that was one of the last in a line of development, it was very capable and only went out of use when development funding ceased after the military chose Microbolometers as their preferred 'silent' technology.

You can also easily attach a video sender transmitter to the ARGUS2 for wireless video linking. Not something that can be done with many modern thermal cameras that do not include wireless capabilities or a composite video socket ! I like having the old fashioned composite video capability as it is so easy to use and very versatile. No computer needed

Finally, do not forget, it is weatherproof so you can use it outside for wildlife observation without fear of rain damage

Fraser

[Bill W]

One minor point to add to Fraser's excellent commentary 

Argus 2 was only available as 525 line/30Hz/NTSC.  It was never available with 625/25Hz/PAL even if the display PCB has some legend notes on how to make it run in PAL.

Only the later Raytheon BST cores could do 625/25Hz/PAL, and so later build Argus3 could be switched back and forth.

Bill

[Grayo]

Hi Fraser,

I'm sorry to trouble you but am hoping you can give me some advice. I run a search and rescue group for lost dogs here in the UK. What thermal imagine camera would you recommend for for doing this. Sometime dogs are buried deep in thick undergrowth so would need something that can penetrate situations like this. Thanks in advanced for any help you can give.

Graham

[Fraser]

Hi,

I would recommend one of the FLIR Scout II or III thermal scopes that are designed for SAR and observation use. Sadly they are not the cheapest option though. You for not want too wide a field of view as this decreases detection distance. 25 degrees or so for such use is the maximum really.

The Scout II and III contain a high quality TAU 2 core.

There are cheaper Chinese copies of the Scout series but I cannot comment on their performance. Some may be good whilst others apalling. Guide make a similar thermal scope. If you can test it before buying it may be worth a look.

On the used market you will find FLIR thermal scopes from the MS, PS and HS families. All are suitable for your needs, even if the earlier models that use the still excellent TAU 1 module.

You could consider the Keysight U5855A that is available from the Keysight factory shop but that is a gun format and the microbolometer is 160 x 120 pixels. It would work though. Just aye not as well as the Scout series. The U5855A has its own thread on this forum. Cost is $620 +VAT delivered to the UK.

I can comment further if required.

Hope this helps

Fraser

[Grayo]

Many thanks for your reply Fraser, that's very helpful. Yes I've looked into the Flir Scout, but like you say it comes at a hefty cost. Thanks for the advice it's much appreciated.

Regards

Graham

[Fraser]

Do take a close look at the Keysight U5855A. For the money it is hard to beat and the lens is 28 degrees horizontal field of view, so it is close to what I recommended.

The FLIR E4 is another option with the ability to upgrade it to 320 x 240 pixels. It isn't exactly cheap though and the latest 2017 model was presenting problems to the upgrade path. If you buy a used one that is pre 2017, you can still upgrade it. The field of view is a little large at 45 degrees though. That is almost double the FOV of the U5855A. In standard 'as bought' 80 x 60 pixel spec, the E4 is a poor choice due to the low resolution.

Fraser

[Grayo]

Ok thank you again for your very helpful information Fraser, I will have a look at the options you suggest. As you can tell I have no idea at all regarding thermal imagine cameras. I also own a dji inspire 1 drone, and would love to have the flir camera for that but the price is way out of my budget sadly.

Best regards

Graham

[Fraser]

I had hopes of using a 160 x 120 pixel resolution Lepton 3 core in a custom interface PCB for drone use. Sadly the company that makes the interface board appear unable to build a reliable version for the Lepton 3. They have one for the Lepton 2 but the 80 x 60 resolution combined with wide field of view is limiting. I salvage LEPTON 3 cores from faulty FLIR ONE Generation 2 cameras. They cost me around £70 on eBay and I have yet to receive one with a faulty Lepton core.

I will add a link to the Lepton 2 interface in a minute. It provides composite video out so is easy to connect to a video transmitter. The company did show a working Lepton 3 interface a while ago but no sign of it now and they did not even respond to my email enquiry

Fraser

[Fraser]

The Lepton board comes from Flytron......

http://www.flytron.com/thermal-cameras/303-dronethermal-micro-uav-thermal-camera.html

If you want to discuss such further, raise a post on the topic and the whole EEVBlog thermal imaging membership should see it. Such is rather out of place in this thread.

Fraser

[Grayo]

Ok thanks Fraser, I will do. Thank you.

[Bratster]

Hello Fraser,

Do you have detailed photos of any very early gen 1 Argus cameras?

I bought one off eBay a few years ago that was DOA and I was hoping that I would be able to repair it quite easily.

Unfortunately the prior owner had to go him self and screwed with every. single. trimmer. on the thing. [emoji35]

I think the only problem with it was a blown fuse in the power supply board that was in there. I fixed that and it does power up now.

However since all the trimmers got tweaked it does not show an image.

I have played around with adjusting different trimmers at different times and managed to finally see a faint image of a soldering iron but that is it so far. It has been sitting in a box the last couple years.

I'm hoping if you had a detailed shot of both of the circuit boards in it that would at least give me a starting point to set all the Trimmers to.
Then I can then go by one by one tweaking them to get the best image.

Thanks for any help you can give.

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[Fraser]

I'll see what I can do for you. I have several ARGUS 1's around but disassembly is a PITA as there are so many screws etc.

Please post some photos of your PCB's and the PCB identity numbers.

Fraser