Thorn MULTI ROLE THERMAL IMAGER EOD 2/89 - Page 1
Forum section: electronics / general

author: NukeET
author_rank: Contributor
timestamp: June 28, 2021, 07:34:45 am
content: I have come into possession of two thermal imagers: an Amber Radiance 1, and a Thorn MRTI MKIII. Unbelievably, and much to my excitement, THEY HAD THE TECH MANUAL FOR THE THORN!!! I suspect this will be of great value to this forum as I could not find duplicate information anywhere. I'm more than happy to provide drawings and technical data from the manual. In addition, I'd like to find a way to get the entire volume up somewhere public, but I'm wary of the legality of doing so. I can certainly provide answers in the mean time. The manual has a complete parts list with schematic diagrams and many of the NSN/NIINs that I looked up are still valid in the supply systems.Here is what I have done so far:Connected 24v DC to the battery terminals on the exterior of the device. Device powers on, spins up, regulates speed. Great to hear. I opted to use the external battery terminals over the 3 pin Amphenol input because I don't know the pinout or voltage level of that socket, but have lots of information on external battery terminals. The polarity was painted directly onto the terminals which felt pretty safe.Investigated cooling air inlet. Unfortunately I am missing the bottle clamp/filter/valve arrangement. I can see some sort of inlet barb sticking out where that assembly would fit over and I am thinking of a way to safely apply high pressure air to it.I have also gotten a BNC to HDMI converter attached and the device does have a valid video output in this configuration. While I have only static as an image, adjusting all the control knobs seems to have the effect they should.I also have a VERY robust tripod that came in an olive drab crate covered in Hebrew.I suspect that the previous user of the device had some sort of semi-permanent arrangement for it as the BNC for power showed signs of heavy use over the battery terminals. I think this is why the bottle mount is missing. I'm sure they had a much larger air source for it, and the tech manual makes mention of doing this as well. This also explains why mine has the remote control and viewing module instead of the man portable configuration.I'm excited to try applying cooling air, but I am not going to risk anything other than a bullet proof arrangement with 4500 lb air. Not trying to win any Darwin awards here. From what I understand, there is a fairly wide band of adequate pressure, but I have not found reference to a lower limit. The upper limit of the system is 6000 psi.Voltage limits from the battery terminals are 18v-30v (24v nominal). Mine drew abut 2.5 amps at 24v, but stabilized around 2 amps which seemed a bit high, as the tech manual states nominal 15w power draw for my configuration. (7w for "direct view" which is the man-portable version).As an aside, shoutout to Fraser for the information on the Radiance 1. The cryogenics in mine work exactly as he describes, but I am not able to get a video output on s-video or otherwise. In fact, it appears all the IO boards are without signal of any kind. No front panel lights, no signal on any of the jacks. rs232 port is dead quiet. Very concerning, but a topic for another thread.

author: m931
author_rank: Newbie
timestamp: October 28, 2021, 05:44:58 am
content: Hello nukeET.I have the opportunity to also buy a thorn MRTI MKIII, however if I read your story like this you really need the manual,is there any way i can get a copythank you very much for your reach.Sincerely.Coen

author: NukeET
author_rank: Contributor
timestamp: November 13, 2021, 04:23:48 am
content: Sure, shouldn't be an issue! Sorry for the late reply, took me awhile to see this. I still need to make a digital copy of the manual, but in the mean time I'd be happy to give you any information you are looking for.

author: Ultrapurple
author_rank: Super Contributor
timestamp: December 16, 2021, 10:15:52 am
content: I was amused to readthis brief article on the MRTIfrom the mid-80s. It says that "The price of £20,000 to £30,000 for a typical systemmay limit civilian use" (my emphasis) - for historical context,according to the UK Land Registrythe average price of a dwelling in 1984 was around £27,000.

author: Bill W
author_rank: Super Contributor
timestamp: December 16, 2021, 12:51:23 pm
content: Mind you, around then a P4428 firefighter camera was GBP 7420, and the 'big lens' ones up to £10kBill

author: Fraser
author_rank: Super Contributor
timestamp: December 16, 2021, 04:22:21 pm
content: An AGEMA THV880 would have cost you £125K plus £25K for the lens back then. The Stirling Cooler upgrade for it was another £25K Then there was the cost of “BRUTE” the image analysis computer. Note I say computer and not PC as it is nothing like a PC and is a custom design. BRUTE cost a small fortune but I do not recall ever being told the exact amount.Thermal imaging equipment was basically military/scientific grade equipment in that era and carried the associated price premium. Many were also mostly hand built and production labour intensive. That said, scientific institutions and some wealthy Industrial organisations would happily pay £100K+ if such equipment provided what they needed and there were no viable cheaper alternatives. I was was regularly involved with relatively unimpressive compact equipment that cost more than my house and the support costs were equally scary ! A camera service cost £5K to £15K in my experience of cooled cameras. This is why I laugh when people ask me why thermal imaging cameras are still so expensive 🤣 We have never had it so good where thermal imaging capability and associated cost is concerned.Fraser

author: m931
author_rank: Newbie
timestamp: January 03, 2022, 10:28:14 am
content: Hello everyone.Thanks for the additional information,I can buy it for about € 3000,- but then I have to have an idea whether it will really work .Dear Nuke, if you have the documents digitally, you could email them to cdewijs999@gmail.comthank you very much.Kind regards,Coen de wijs

author: Fraser
author_rank: Super Contributor
timestamp: January 03, 2022, 10:34:02 am
content: m931,Please think very carefully before spending 3000 Euro on such a unit. It is a museum piece compared to modern thermal imaging systems. If you are a collector of Military equipment it may be worth that much to youOtherwise, I suggest you walk away.Such a unit is worth a few hundred Euro’s at best. These are often scrapped for the value of the Germanium lens elements which is around £400/Kg in the UK at the moment.3000 Euros will buy a very sophisticated thermal camera on the used market so have a look at what else is on offerFraser

author: m931
author_rank: Newbie
timestamp: January 04, 2022, 07:21:37 am
content: Dear Fraser.Thank you very much for your good feedback.what I'm actually looking for is a thermal unit that I can install on my humvee that is from the gulf war era,so I'm not really looking for a modern unit ,maybe you know other models that are better suited for these applications.thank you very muchcoen

author: Fraser
author_rank: Super Contributor
timestamp: January 04, 2022, 09:18:59 am
content: I know of a more suitable unit. I will see if it is still for sale.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: January 04, 2022, 09:40:38 am
content: I just realised that you wanted a handheld unit rather than vehicle mounted. The unit I previously saw was a static vehicle mount for the driver to use.If you just want a Gulf War era handheld thermal camera then consider buying a Raytheon L3 X100 or one of its successors. There was the Raytheon L3 X50, X100, X150 and X320. The X100 saw military service in the gulf. I own one that was used in that theatre of battle plus a X50 that I reconfigured to an X150 resolution using the factory configuration utility.https://www.militaryaerospace.com/communications/article/16709121/optoelectronics-watchFraser

author: m931
author_rank: Newbie
timestamp: January 04, 2022, 03:51:05 pm
content: hi Fraser.thanks for the link.And no, I'm just looking for a fixed unit.I have a gun turret on my humvee and would like to mount it on that, in addition to the M60 mount that is already on it.could you see if this is still for sale?thanks

author: Fraser
author_rank: Super Contributor
timestamp: January 04, 2022, 04:07:36 pm
content: I could not find it in a quick search earlier but will have another look. It is a proper military cased camera that contains both visible and thermal imaging cameras. The thermal camera is a BAE unit, I seem to recall it was an SCC500 microbolometer core. A chap on the forum bought one and did a teardown. I will see if I can find that for you. The seller of the cameras is located in the UK and is a Government surplus dealer. They were around £400 complete in their original, casing and came in two versions…. Green aluminium “lightweight” cased for land rovers etc and Green armoured steel “heavyweight” cased or armoured vehicles. They were intended to be mounted on the roof or other horizontal surfaces as they are not pan/tilt.These are age appropriate for the Gulf War.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: January 04, 2022, 08:32:39 pm
content: OK, I found the camera auction. The seller is asking a lot more fir the unit than I saw them fir a year ago. It would be worth negotiating.https://www.ebay.co.uk/itm/TANK-ARMOURED-VEHICLE-DRIVERS-FORWARD-FACING-THERMAL-IMAGING-CAMERA-/273998849934?mkcid=16&mkevt=1&_trksid=p2349624.m46890.l49286&mkrid=710-127635-2958-0I will look for the forum post that details the internal parts and how to power the thermal camera for use of the video output.Fraser

author: Fraser
author_rank: Super Contributor
timestamp: January 04, 2022, 08:36:15 pm
content: I own a couple of military cameras from the Iraq conflict as well. They produce composite video and are long range surveillance units. They use a large microbolometer sensor array of 320 x 240 pixel resolution. Mounting is via a built in tripod mount plate. I might be willing to sell one.Fraser

author: m931
author_rank: Newbie
timestamp: January 05, 2022, 07:11:35 am
content: Goodmorning.yes such a kind of thermal camera I am looking for , but then one that works and is complete , thanks ,and the camera you have what would you like for that ? ,and what kind of connection is on it so that I can find a matching monitor for it ,