Author Topic: Thermal Camera teardown - Raytheon Cadillac DeVille Thermal Nightvision camera  (Read 13257 times)

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Offline Fraser

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I dug my two Raytheon Cadillac DeVille cameras out of the 'awaiting repair' pile today.

Both cameras need a new chopper wheel as detailed in a previous post on these thermal cameras. The membrane of the chopper wheel can split over time in these cameras due to the constant heat to which they are exposed. This was also an opportunity to inspect the PCB's for any potential issues. IT is just s well I did as there was an issue with both. The problem took the form of tantalum capacitors that are splitting ! They have not burned-up as is their usual form of 'suicide' but cracked cases cannot be good so they are going to be replaced. Only one value shows this issue on both cameras, 330uf @10V rated. Both cameras were built in late 2000. I have marked the cracked capacitors with a blue marker to identify them but I will replace all the 330uF Tantalums as a precaution. There are quite a few used in these cameras.

By way of introduction to these cameras, they are designed and built by Raytheon for Cadillac and based on the Raytheon Thermal Eye 300A. The sensor is a Peltier temperature stabilised BST FPA. A chopper wheel is required for this sensor and is the standard Thermal Eye part. All electronic components are located on a single PCB with the rear of the case acting as a heatsink for the Peltier element. The lens is mounted in the plastic front section of the case and comprises a large diameter Germanium element combined with some form of plastic lens at the rear. An unusual lens design likely to be due to BoM cost restrictions for the camera. The fragile Germanium lens is protected from stones and dirt by a Germanium window that may be changed by the owner if it is damaged. In an automotive deployment, such a lens protector is essential if no other form of lens impact protection is employed. The Germanium window is heated in very cold weather by a built in heating element ring and thermostatically controlled.

The important specs now, the camera has a 320 x 240 pixel BST array and the output is 60fps making it suitable for use on a fast moving platform. The BST camera does not need the FFC flag and event found on many microbolometer cameras so there is no frozen frame distraction for the driver. The BST FPA was and still is an excellent choice for automotive deployments. As a 60fps 320 x 240 pixel thermal camera made by Raytheon, these are liable to ITAR regulations if being shipped between countries.

EDIT - Correction on import/export rues by Bill W who knows a lot about such......

"A slight correction on export controls, these are not ITAR but are Wassenaar dual use controlled so need a license to cross borders, apart from internally within the EU."


Hope you enjoy the pictures.

Fraser
« Last Edit: August 09, 2016, 04:42:32 pm by Fraser »
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Offline Fraser

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Inside the rear case
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Offline Fraser

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More
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Offline Fraser

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Offline Fraser

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Failed 330uF 10V tantalum capacitors. Marked with blue marker pen.
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Offline Fraser

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The Patent detailing the design of this camera is attached.

The automotive deployment Patent US5763882 of 1998 is a duplicate in many areas but describes a 'low cost night vision camera'

http://www.google.co.uk/patents/US5763882

It should be noted that the term 'low cost' was relative to the industrial thermal cameras of that era costing more the $40K. These cameras were not a cheap option from Cadillac, that is for sure.

The Cadillac DeVille cameras are still popular and to be found on ebay. They range in price depending upon condition but expect to pay between $150 and $500. Their popularity stems from their rugged construction and ease with which they may be deployed on a vehicle for navigation in the dark and hunting. You just feed the camera with 12V DC and it produces NTSC composite video. No adjustments or commands, it is fully automatic and simplicity itself. People on You Tube have shown these being used in Pan Tilt Lamp housings an bolted behind the grille of their cars. They cost less than the Audi and BMW Autoliv FLIR cameras and, unlike those nightmarish units, the Raytheon is easy to deploy without any hacking needed.

Note that many of the cameras on the market are circa 2000/2001, will have broken lens protectors and split chopper wheel membranes. As such these should be dismantled, cleaned and serviced if you want the best out of them. Many You Tube videos using these cameras show signs of a poorly camera in need of some TLC.

As a point of interest, these Raytheon BST sensors and electronics design are used in EEV(E2V) ARGUS 2 and ISG Talisman firefighting thermal cameras.

Fraser
« Last Edit: August 09, 2016, 04:39:17 pm by Fraser »
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Offline Fraser

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Interesting Kemet Tantalum failure analysis document. It even shows a thermal camera being used to detect failed Tantalums.

Fraser
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Offline nidlaX

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Nice teardown and info Fraser!

Do these sensor modules have any type of temperature read-back capability built in?
 

Offline Fraser

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NidlaX

No sadly the BST sensor array in this camera is non radiometric and does not easily provide precise temperature output for radiometric tasks. There have been clever designs using  the BST sensor that enable it to be used in radiometric applications, but for such tasks the microbolometer is a better choice.

Fraser
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Offline Bill W

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The temperature measuring options on fire cameras that used the Raytheon BST (EEV Argus2, Marconi Argus3, ISG Talisman/K90) all used Raytek spot temperature sensors aligned with the camera view.
The BST is a 'ferroelectric/pyroelectric' detector so responds to changes in energy, hence the chopper, so is unsuited to measuring temperature by itself.  The only way is if the chopper is both solid and its' temperature is known when it becomes a bolometer that shutters at video rate.  The standard chopper is translucent and acts as an unsharp mask filter, which gives the BST image its' classic dark halo effect.


http://www.fire-tics.co.uk/images/A2R_TI.jpg

A slight correction on export controls, these are not ITAR but are Wassenaar dual use controlled so need a license to cross borders, apart from internally within the EU.


Bill

www.fire-tics.co.uk

Offline Fraser

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Removing the chopper wheel from a Raytheon Thermal Eye camera .......

The Chopper wheel is a pretty fragile assembly that is attached to its drive motor using a press-fit. That is to say, no screw or adhesive is used.

The frame of the chopper wheel would break if any attempt was made to use it in the removal process. The removal requires care and an understanding of the 'hard points' on the wheel. There is only one hard point on the chopper wheel, the central boss.

If the membrane is totally destroyed and of no use, it would be feasible to use the standard knob removal technique where a strong nylon cord is threaded under the hard point and used to pull the assembly off axially. There IS a risk of breaking the central boss however. I opted for the leverage approach as that is safer and preserved the membrane for the purposes of templating a new one.

There must be no levering on the fragile frame, only the central boss. In order to achieve this I borrowed a serrated edge bread knife from the kitchen. This has a strong but thin blade and the serration permits force either side of the motor shaft rather than just on one side. To assist in the process of removal I heated the boss with a hair dryer for around 15 seconds on high heat. The knife is then twisted carefully to prise the boss off of the shaft. On my cameras the boss popped off easily. Take care and take your time. Rotate the boss 90 or 180 degrees if it is being stubborn and this will work it off of the shaft.

When the chopper wheel is off of the shaft you can see a reflective indexing disk on the rear. this works with an IR reflection sensor on the motor deck to provide chopper wheel position sensing for the synchronous chopper spiral timing circuits. It is very important that this index is correctly positioned with respect to the spiral start point.

Fraser
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Offline Fraser

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The chopper wheel mask is made up of translucent dots so is hard to photograph. I found a blue background helped so i have taken some pictures that i hope will help others to make their own replacement spiral chopper shape for use with the original wheel frame. Opaque spriral's will work for most peoples applications of these cameras.

There is another chopper wheel in one of the pictures. It is from an EEV Argus 2 camera. I have yet to establish the compatibility of this slightly different chopper wheel with the Cadillac camera.

Fraser
« Last Edit: August 09, 2016, 04:26:47 pm by Fraser »
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Offline Fraser

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Higher resolution chopper wheel image
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Offline Fraser

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Raytheon Cadillac camera Chipset

Altera FLEX EPF10K100EFC256-3    10K series FPGA

ISI 61LV6416   64K x 16 SRAM 3V3

AMD L400BB55RI   256K x 16 Boot sector Flash Memory

ADV7127    240 MHz 10 Bit High Speed DAC

Analogue Devices M 01   Tiny RS232 Transceiver

NAT Semi 01AB CLC5602IM  Dual high output video amplifier 

TI HB244 98K EELD    Tri-State Octal buffer

OP279 G 943 G3332  Dual high output current Op-Amp

LT 945 112913     Low dropout regulator 1V3

4412   Mosfet

AD9220 ARS 9931 AP6958.1   12 Bit ADC

Altera EPC2 TI32 Cad489949   Altera 10K configuration Flash RAM

H 1135IB    360Mhz video Op-Amp

NAT Semi JM86AB LMC6084IM   Precision CMOS quad Op-Amp

Zetex T6790   Diode array

OP279 G009 G8986     Dual high output current Op-Amp   

NAT Semi 02AB LMC 6082IM  Precision CMOS dual Op-Amp

LT  012 1624I    Switching Regulator controller

LT 002 111825     Low dropout regulator 2V5

Raytheon 2270-35  BST 320 x 240 Pixel Array
« Last Edit: August 09, 2016, 06:12:39 pm by Fraser »
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Offline SeanB

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Very nice Fraser. From your linked paper it looks like those caps were cracked by improper storage before soldering which started the cracking.
 

Offline AKMac

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For someone also attempting a repair on one of these cameras, with I'm guessing a burnt voltage regulator and several failed capacitors, how do you determine information about these tantalum capacitors? I notice that the 330uF caps say 337 on top; are those numbers related?
 

Offline Fraser

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AKMac,

Just Google "Tantalum capacitor markings" and all will be explained. There is a voltage rating as well  ;)

http://www.radio-electronics.com/info/data/capacitor/capacitor-markings.php?sa=X&sqi=2&ved=0ahUKEwjjm5381aPZAhUnBsAKHUPPBoUQ9QEIDjAA
« Last Edit: February 13, 2018, 07:57:01 pm by Fraser »
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Offline Bill W

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A common failure mode is that of tantalum capacitors used  on power input or SMPS smoothing being hit with surge current.  That is more a total burn out than the cracks Fraser shows.  The Raytheon BST Core used standard tants (for example AVX TAJ series etc) in a few places where it would have been better to have used surge rated (for example AVX TPS).

From Frasers' pictures it looks like a one size fits all design approach with the biggest Tant they could find (330uF).

The 200 / 205D core for OEM use had 220uF for the actual sensor biases etc, and I don't recall any 330uF on the SECCA (processing PCB) either.  It was the SECCA ones that burnt up.

The Cadiallac PCB looks like both those OEM PCB combined, but without some of the OEM interfaces.

Bill

Offline Bill W

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Had a check, and the 'newer' SECCA from the 205D OEM core has one or more 330uF/10V/0.2 ESR on all the switch mode supply voltages - of which there are quite a few.
That dated from 2003.

The older '200' series from 1996 to 2002 used 220uF's and a lot less voltage rails pretty much all on 5V.

Bill

Offline bostwickenator

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Necroing this topic since it's the best source of information about this camera I can find on the internet. Also backlinking to Fraser's previous topic: https://www.eevblog.com/forum/thermal-imaging/thermal-camera-affordable-raytheon-night-vision-thermal-camera-unit/

@Bill how does one go about figuring out this is controlled by Wassenaar over ITAR? Is it a matter of criteria or is some master list of device models kept?
 

Offline Bill W

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@Bill how does one go about figuring out this is controlled by Wassenaar over ITAR? Is it a matter of criteria or is some master list of device models kept?

There are lists of criteria over what is under Military item controls (US=ITAR) what is under dual use item controls (US=EAR)
All the dual-use regulations have simply lifted the text from Wassenaar and dropped it into their national documents (US=EAR, EU27= regulation 428/2009).
For the US there has often been a turf war between Dept of Commerce (who run EAR, and get moaned at by manufacturers) and Dept of State (who run ITAR and get moaned at by the military fearing assault aided by dual use items).

As the UK has a single document for both MIl and Dual-Use lists, the UK explanation is quite helpful:
https://www.gov.uk/government/publications/uk-strategic-export-control-lists-the-consolidated-list-of-strategic-military-and-dual-use-items-that-require-export-authorisation

A key point is that while the lists say WHAT is controlled, they do not say much what the restriction then should be.  Each license application can be treated individually (especially by the US) and restricted accordingly.
So by example with BST cores:
EEV/Marconi got BST cores in crates of 24 on a 'any of these countries/user types' and  'tell us where they went at the end of the month' basis.  We were a UK approved big corporate military supplier with all the compliance that goes with it.
ISG only got BST cores one at a time after each core had a pre-approved end user.  They were a small private company.


Bill
 
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Offline bostwickenator

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Bill that is an amazing answer thanks for taking the time to write that up for me.

From my read of the document you linked this camera falls under 6A002.a.3.g but isn't excluded from regulation because it fails "Incorporates an active mechanism that forces the camera not to function when it is removed from the vehicle for which it was intended;"
 

Offline Bill W

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Thanks.  Not sure your para number is right, although the wording is.  6A002 applies to sensors, (6A002.a.3.f being thermal camera ones) while cameras 'using sensors of 6A002' come under 6A003. 

The restricted features (and exemption clauses) for thermal cameras are 6A003.b.4.b and following notes
The clauses in Note 3.c cover vehicles, added specifically for Cadillac/BMW etc to be able to export cars or for owners to drive internationally.  Probably illegal to drive a TIC fitted car to Belarus though.

The US EAR document is here:
https://www.bis.doc.gov/index.php/component/docman/?task=doc_download&gid=2338 but is a lot harder to read
It does however include more on US control policy, one of which allows medium performance finished cameras (eg 60Hz 320x240) out to friendly places, but not cores for those friendly places to build their own cameras !
FLIR must have written it......  ???

Bill

Offline bostwickenator

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You are right I was off my one!

6A002.a.3.f. Non-“space-qualified” non-linear (2-
dimensional) infrared “focal plane arrays” based
on ‘microbolometer’ material having individual
elements with an unfiltered response in the
wavelength range equal to or exceeding 8,000 nm
but not exceeding 14,000 nm;

I wonder if the text I quoted about an interlock was added after Cadillac stopped shipping these cameras. From the descriptions of the Volvo/BMW thermal units they use a software interlock.
 
 

Offline bostwickenator

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My unit arrived today a little bit of wire loom bodging was enough to get me some sample footage. A few notes about this unit.
  • They did not skimp on the amount of glass fiber in the plastic of the casing. I handled the unit for all of 3 minutes total and my hands are still itching hours later.
  • The chopper wheel is kinda loud, it sounds like an off balance CD. Turning the camera around even at moderate angular velocity causes clattering noises from the disk :/.
  • The field of view is pretty tight it seems well designed for it's purpose in that regard.
  • At startup the camera draws 4 amps for a second or so.
  • The SNR is a little disappointing. I don't think this compares favourably to my Seek Thermal Compact Pro in this regard. I'll do side by side tests
I'm wondering if the chopper wheel is damaged or somewhat opaque due to age. It feels like the camera should perform a bit better than this. I'll pop it open and see soon.

Test video
 

Offline Fraser

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This is the sort of video that is commonly seen from owners of these old cameras..... no that is not the image quality that I would expect to see from this well made BST core. It is a little sick.

To cover your points.......

The GRP casing can start to degrade due to age and exposure to weather. None of my cameras have the issue that you describe so yours is seriously weathered.

The chopper wheel should spin up to operating rpm and only be audible as a whir if you move your ear close to the camera. A noisy chopper wheel suggests either a ripped membrane (likely) or a failed motor bearing (unlikely unless very high hours or water ingress has occurred)

The FOV was intended to cover the road ahead for approximately the width of the high beam headlights but to a greater detection range.

High current draw at initial start is normal for these cores but 4A appears high to me. The current draw is increased at start by the microbolometer heater that raises the microbolometer temperature to around 32C. Once at this temperature, the drive to the heater is reduced. There is also a front window heater that is controlled via an  external ambient temperature measuring circuit. That heater, when activated, will also draw significant current but in your test case, may be ignored.

Yes your image is not up to the expected standard. I suggest a failed chopper wheel membrane. It will likely have rips in it. The membrane does discolour with age but this is not an issue. It is tearing of the membrane that is the issue. A new opaque type chopper wheel may be 3D printed and this works OK for many applications. Bill W has new chopper wheels but you need to compare the chopper wheel membrane spiral to determine if they are the same.

When you have the camera disassembled it would be a good idea to fit all new tantalum capacitors of the same, or better specification. They are subjected to a hard life in these cameras and can degrade over time. Complete failure can lead to a ‘burn-up’ that damages the PCB.

Fraser
« Last Edit: January 31, 2021, 04:45:13 pm by Fraser »
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Offline ArsenioDev

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Fraser, I dealt with this exact problem on one of my cameras during installation into my friend's FJ cruiser as a NAVFLIR system, above poster has an alright camera, it's just decently out of focus. Unscrewing that gasketed hex screw at the back, then feeding an allen key up the port opened to turn the gear train to move internal focus mechanism while camera is running to nice sharp video. Definitely looks like he's running the 2x zoom software option inside the camera, not sure how to disable that.
 
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Offline bostwickenator

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So THAT is what that screw is for! I hadn't thought too much about the mechanical assembly up front figured it was aperture control from a glance at Fraser's photos but now I think about that it's pretty obvious that doesn't make sense. I'll try adjusting the focus shortly. edit: Imperial hex! :palm:

Follow up I didn't know there was a digital zoom feature on these. There are only the two output lines aside from the power. Without any service IO port I suspect any options would be by either be set at firmware load time or controlled by a PCB jumper. I'll have a look around when I open it up.

Fraser I think you are probably right. It's likely got damage to at least one quadrant of the chopper from the fluttering sound. I should be able to print a replacement if that is true. I'll throw some CAD models up here if I do. edit: Well that will save me some CAD time https://www.eevblog.com/forum/thermal-imaging/raytheoncadillac-deville-camera-3d-printable-focusing-mod-and-chopper-wheel/
« Last Edit: January 31, 2021, 07:01:51 pm by bostwickenator »
 

Offline ArsenioDev

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One of the first things I figured out was what that screw did.
Also, it's BST so your SNR won't be that great in comparison to more modern VOx systems. My 08 and 10 vintage L3 QVGA sensors beat the absolute PANTS off my '02 and the BSTs, even the customized ref design version that has digizoom disabled.
 

Offline Bill W

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The chopper wheel should spin up to operating rpm and only be audible as a whir if you move your ear close to the camera. A noisy chopper wheel suggests either a ripped membrane (likely) or a failed motor bearing (unlikely unless very high hours or water ingress has occurred)

The CD motor bearings used on later models are not great, and the mounting is not ideal with the wheel hanging off the front (although Argus was far worse).  Only the earlier 200 analogue cores had the Swiss motors.  later digital cores used cheap CD spindle motors, but of course horizontally mounted.

I've loads of the motors (correct voltage) if anyone needs one.

Bill

Offline Bill W

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I wonder if the text I quoted about an interlock was added after Cadillac stopped shipping these cameras. From the descriptions of the Volvo/BMW thermal units they use a software interlock.

The text has been present since the major 2007 edit of Wassenaar (when all the 9Hz / silicon sensors clauses were changed), so predates a lot of BST production.  The concerns and need for change however came from the use of BST in civilian vehicles.
2007 wording:
Quote
c.   Where the camera is specially designed for installation into a civilian passenger land vehicle of less than three tonnes (gross vehicle weight) and having all of the following:
1.   Is only operable when installed in any of the following:
a.    The civilian passenger land vehicle for which it was intended; or
b.    A specially designed, authorized maintenance test facility; and
2.   Incorporates an active mechanism that forces the camera not to function when it is removed from the vehicle for which it was intended.
Note   When necessary, details of the item will be provided, upon request, to the appropriate authority in the exporter’s country in order to ascertain compliance with the conditions described in Note 3.b.4. and Note 3.c. above.

It is up to the origin state to determine if the clauses were adequately met by any given design.  Proir to 2007 BST was controlled anyway, so did Cadillac not ship TIC equipped outside the US/Canada ?  As it would be under EAR, the US would likely make an exception for Canada anyway as Canadians cannot drive anywhere else.

Still does not cover what should have happened at the US-Mexico border.

Bill

Offline bostwickenator

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Built a test housing for it and I figured out some of the sound. The position sensor for the chopper wheel has a tiny plastic spring clip holding it in place. Or it's supposed to, half of the clip was rattling around inside the camera and the position sensor was loose enough it touched the wheel when you moved the camera around. There is still a little chattering noise. Also gave the sensor a quick wipe down. Oddly I'm getting really low power output on the composite line. My mini LCD will work correctly on it but that's the only monitor that will. All the front side caps test sane values. I don't really want to be poking around on the PCB. It might be easier to add an opamp to boost the output.

Also, it's BST so your SNR won't be that great in comparison to more modern VOx systems.

This really surprises me. The sensor size is so much larger I thought that the noise would be orders lower. The pyroelectric effect must be massively less efficient than I supposed.
« Last Edit: February 08, 2021, 11:00:27 pm by bostwickenator »
 

Offline Fraser

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Nice housing  :-+

If it is 3D printed, would you be willing to share the STL file please ?

Fraser
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Offline ArsenioDev

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On the low voltage output, I saw this as an issue on several of my units, it was a challenge of putting it in my best friend's FJ as a NAVFLIR. A nice video amp did the trick perfectly and made locking onto the signal easy
 
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Offline Bill W

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This really surprises me. The sensor size is so much larger I thought that the noise would be orders lower. The pyroelectric effect must be massively less efficient than I supposed.

The BST is specified as NETD=80mK, current ASi are 60mK and VOX usually around 40mK, if using an f/1 lens and the factory test bench electronics. 

Most of the sensor improvements that could have led to lower NETD have instead gone into pixel size reduction (reduced sensor and lens costs) and less fussy electronics requirements especially on bias voltage noise.  With VOx in particular the lower NETD has simply resulted in the tendency to fit smaller aperture lenses, so a 40mK sensor with an f/1.4 lens is effectively back to being 80mK in the image.

BST has the 'halo' effect from the chopper wheel but will also always be free of fixed pattern noise, something that does not get factored into NETD figures.  The relatively crude automatic gain control does not do the BST any favours.

Bill

Offline bostwickenator

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Thanks @Bill :). Maybe I'll pick up a more performant VOx device one of these days. Hopefully lenses get faster if these new reverse vulcanized Sulphur plastics become a thing.

@ArsenioDev thanks again for the help. It's great to hear that I'm not alone in that. Oddly it definitely had a stronger signal when I first turned it on. Evidenced by the video I recorded and included on previously. Makes me wonder if it's dying on me or if my wiring has such bad impedance mismatch I'm losing all the power. Regardless I ordered some highspeed opamps and I'll try adding a booster to the output signal. I included a BNC video output on my case design and as such I feel obligated to make that work lol.

@Fraser Well I picked up some replacement caps because of the above concern something is dying. I need to check the underside of the board. How bad was getting the connector off the PCB am I in for a fight?

Including an image of the position sensor bodge repair
 

Offline Fraser

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Removing the PCB from the surface soldered connector pins was pretty simple. Just use plenty of good sticky flux and decent desoldering braid/wick and it will wick away the solder. Then press a little on the PCB next to the connector as a soldering iron is applied to each pin and joint opens. The PCB then just tilts up and out of the casing.

Fraser
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Offline bostwickenator

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Ah cheers, I haven't worked with this style of connector before and was expecting to have to pull remove the retaining pin and pull the connector out of the housing after desoldering it. If I can pivot the board out with the connector in place that will be much better. I'll update after my caps come in.
 

Offline bostwickenator

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Update I am an idiot. I'd wired the video ground to the system ground. I thought I had bench tested that being ok but apparently I misremembered my collection of alligator clips :-/O. Now that I separated the two ground planes and the video output works perfectly again.
 

Offline Fraser

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 :-+
Cogito, ergo sum
 

Offline simply

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  • Posts: 1
  • Country: se
Built a test housing for it and I figured out some of the sound.

That housing looks awesome - are you able to share the design for it?

Just rescued a Thermal Eye 4000M from the scrap bin. After som cleanup it works like a charm, and with a nice case, it could be put up for some good use too!
I've got a SmallHD screen that will make a perfect "portable" combo.

Rgds
/Andreas
 


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