Thermal Camera - The EEV Argus 1 (P4438) - under her clothes ! - Page 1
Forum section: electronics / general

author: Fraser
author_rank: Super Contributor
timestamp: July 07, 2015, 06:06:26 pm
content: The EEV P2238 ARGUS 1 Thermal CameraAmongst my collection of thermal cameras I have several EEV ARGUS thermal cameras. These come up on ebay now and then so I thought I would provide an insight into one of them, the ARGUS 1 Fire fighters Camera.I may provide similar for the ARGUS 2 (BST Detector) camera in future.The ARGUS 1 was manufactured by the English Electric Valve Company (EEV). EEV were the first company to manufacture a hand portable uncooled thermal camera for the Military. This unit is based on their original military camera design named the P4428 and uses a Pyroelectric Vidicon tube. This is thermionic valve technology but it still performs well. Those familiar with Vidicon CCTV camera tubes will feel very at home working on the ARGUS 1 as she is similar in operating principle.As stated, the ARGUS 1 is the successor to the original P4428 (aka “The Dustbin”) and it has the model designation P4438. The electronics were refined using more modern components but the optical block is little different.A Germanium lens illuminates the thermally sensitive face of the Pyroelectric Vidicon (PE Vidicon). A mechanical iris in the lens assembly controls the energy passing out of it and acts to avoid overload situations. The PE Vidicon requires a chopper wheel to be placed between it and the lens assembly. In the ARGUS 1 the chopper wheel is constructed from very thin FR4. It is driven by a high quality coreless motor and synchronised to the video stage. The chopper wheel sets the frame rate and this is 30 frames per second in the ARGUS 1.The PE Vidicon operates by having an electron beam scanned across the thermally sensitive surface by H and V deflection coils to form a Raster, as found in conventional Vidicon cameras and CRT televisions. The thermally sensitive surface is called the Target and its output is fed to a high impedance amplifier. The signal is then processed in a similar manner to the conventional Vidicon camera. I shall not go in to detail here as that will take too long. Google will supply plenty of information on the Vidicon camera operating principles.The unit basically consists of the following sections:1. Optical Block2. PE Vidicon tube3. H and V drive for PE Vidicon and CRT tubes4. Chopper wheel Synchroniser5. Video processing & AGC Block6. Battery level meter & overlay circuit7. Power Supply, HV & LV8. CRT monitor assemblyI have the full service manual for the ARGUS 1 as it is not covered by ITAR. Regrettably I cannot share it as it was provided under a NDA that I would not wish to break. I am however including the adjustment point images of the PCB’s as that is not enough detail to break the NDA.The camera has three PCB’s as shown in the attached images. They are simple to access and very easy to work on. Areas worthy of note on the PCB’s, The high impedance input amplifier from the Target output is contained inside a shielded can, as you would expect. The unit makes use of several ceramic substrate daughter boards that use DIL format connections to the PCB. An unusual design feature in such a camera, that is not found in its predecessor. The camera also contains an ‘hours run’ meter. I love to see those in equipment as it provides an idea of the run time on a unit.It should be noted that the PE Vidicon tube in a thermal camera is a dynamic device in terms of the correct bias voltages applied to it. Over time the characteristics of the tube change and it requires the bias voltage to be adjusted to achieve the best possible image quality. The service manual provides full details of how to service and maintain these cameras. I love quality service manuals like this.The camera is designed to survive in the hostile environment that Fire Fighters endure so its construction reflects this. The outer yellow shell is heat and flame resistant. Under this replaceable shell there is a special thermal blanket pre formed to fit the module that it protects within. Once the yellow shell and thermal blanket have been removed, the black camera module may be seen. This is a sealed unit that is designed to protect the electronics from immersion in water. The outer yellow shell is fitted with waterproof gaskets for this reason as well.The black inner casing is easily opened to provide access to the electronics within. I have included another ARGUS 1 in the image to show it complete, the inner black module and the electronics. I own four of these cameras. They had a tough life but survive well. One of mine was used for training and is pristine. It never saw real smoke in its life, unlike the other example I have that still small of smoke and are a little marked as would be expected.I found someone selling just the M509B Pyro-electric Vidicon tube on ebay so I am including those images here rather than dismantling the camera to duplicate what they show.Ok to the pictures……. Enjoy ………The PDF's of the PCB adjustment points is included under "Argman 3d" and "Argman 3e"They will come in several posts due to their size and number.Aurora

author: Fraser
author_rank: Super Contributor
timestamp: July 07, 2015, 06:07:02 pm
content: The EEV M509B Pyro-Vidicon tube......

author: Fraser
author_rank: Super Contributor
timestamp: July 07, 2015, 06:07:36 pm
content: More Pics

author: Fraser
author_rank: Super Contributor
timestamp: July 07, 2015, 06:08:00 pm
content: More Pics

author: Fraser
author_rank: Super Contributor
timestamp: July 07, 2015, 06:08:33 pm
content: More Pics

author: Fraser
author_rank: Super Contributor
timestamp: July 07, 2015, 06:09:15 pm
content: More PicsDetail of Iris drive, Chopper wheel, tube connections and Chopper Wheel motor

author: orion242
author_rank: Unknown
timestamp: July 07, 2015, 06:46:54 pm
content: Pretty cool. You must have a small fortune stuck in all these cameras.So how much does one like this run on ebay, etc?How does its performance compare to today's low end cameras?

author: Fraser
author_rank: Super Contributor
timestamp: July 07, 2015, 06:51:56 pm
content: The original P4428 is shown here. She was nick named the "Dustbin" by EEV techs due to her shape.I own a couple of these and they still work over 30 years since their manufacture in the early 1980's.Aurora

author: Fraser
author_rank: Super Contributor
timestamp: July 07, 2015, 07:05:18 pm
content: @Orion242,I collect them and buy units at very good pricesThese P4438 ARGUS 1 cameras often need some TLC due to age so I pick them up for between £50 and £125. My 'as new' unit cost £102 a couple of years ago. I repair them for fun.The Pyro-vidicon cannot compete with the image produced by a BST or Microbolometer staring array. The images are softer in appearance, but they still show thermal details. They do have an advantage over 9fps cameras though as they run at around 30fps. Not such an issue in the USA however.I have tracked down some pictures from the internet. The cameras used to make those images could do with some adjustment as better images are possible.I bought these cameras only because I collect thermal imaging equipment. I have an interest in the technology within them. Also... try getting your hands on a service manual for a BST or Microbolometer cameraAurora

author: Fraser
author_rank: Super Contributor
timestamp: July 07, 2015, 10:14:06 pm
content: As if to prove that thermal cameras can be had for next to nothing, take a look here:http://www.ebay.co.uk/itm/Agema-Thermovision-470-Camera-C-w-Case-/261950665269?pt=LH_DefaultDomain_3&hash=item3cfd79f235&nma=true&si=6F%252F1D4DGGHvo3WKYQV4KD39%252FLLA%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557An Agema 470 is a thermo-electric cooled scanner based camera that produces decent images.It sold for only £10.50These cameras are worth significantly more than that but the market is often unfamiliar with them and people think they need Liquid Nitrogen or have Stirling coolers. They use a multi stage Peltier Cooler providing -70C at the detector element.I couldn't be bothered with this camera as it is collection only and located in Central London. This may also have impacted upon its selling price.Sadly the buyer of the camera may not have realised that the camera is without its lens as the seller sold them separately.The black stub protruding from the front of the camera is the lens mount and its cap. He won neither of the lenses so unless he has some, he has a paperweight.The two associated lenses sold for £35 & £40, which is still cheap....BUT I hope the buyers realised that the lenses are Shortwave AR coated versions and will not work with a microbolometer camera. They are also what I call 'partial lenses' .One half of the two lens elements is in the barrel and the other half is in the camera body. As such the lenses only work with the correct host camera.The above demonstrates that bargains are available, but the buyer needs to know his/her stuff about such cameras. It is easy to make mistakes.Aurora

author: lukier
author_rank: Unknown
timestamp: July 07, 2015, 10:48:10 pm
content: Very interesting. Usually any kind of thermal imaging gets a lot of attention on eBay and the prices rise beyond student's budgetAurora: Are CO2 laser lenses (ZnSe I believe, maybe Germanium too) are somewhat suitable as a cheap replacement for a thermal camera (as you say, these things are fragile and suffer corrosion)? These seem to be relatively cheap.

author: Fraser
author_rank: Super Contributor
timestamp: July 07, 2015, 11:17:49 pm
content: @lukier,Replacing a thermal camera lens is not that simple I regret to say.The correct lens elements are needed. CO2 laser lenses are available in ZnSe and GaAs. Germanium lenses are very expensive and specialist. CO2 laser lenses are small diameter and cheap due to mass manufacture. They are not a complete camera lens structure as that requires at least two lens elements that are matched to each other and the back focus distance.The FL of most CO2 laser lenses is not appropriate to building a replacement lens assembly for a camera.A better choice is to buy a used thermal camera lens as these come up for sale on ebay quite often. They are usually from ex fire brigade cameras or similar. Such a lens is likely to work with a long wave camera detector but you must consider the required back focus distance. Modification of the mount is almost certainly a requirement.I work with thermal cameras as a hobby so I can 'play' with lenses etc. It would not be so easy to make a decent camera from parts unless you really know what you are doing.Aurora

author: Setrel
author_rank: Newbie
timestamp: May 30, 2017, 10:12:32 am
content: Bonjour,Nous recherchons une camera EEV P4438 en état de marche.Quelqu’un d'entre vous, pourrait-il nous faire une proposition?La P4438 étant obsolète, Peut-on disposer des schémas électronique?Merci de votre aide, passez une agréable journée.Hello,We are looking for an EEV P4438 camera in working condition.Could any of you make a proposal?Since the P4438 is obsolete, can the electronic diagrams be available?Thank you for your help, have a nice day.

author: Fraser
author_rank: Super Contributor
timestamp: May 30, 2017, 03:25:19 pm
content: The P4438 is really a museum piece now. Care to share why you want one ?They do still work as a thermal camera but most that are to be found now will need a good service, and the PEVICON tube bias voltages re-set due to ageing. For this reason I cannot recommend a used P4438 unless it has been recently serviced. Servicing such a camera is not commercially viable due to the cameras low value and the time it takes to service. These are very much a hobbyists project camera.The service manuals for the EEV cameras, even the old ones, are not public domain documents.Fraser

author: Ultrapurple
author_rank: Super Contributor
timestamp: August 12, 2017, 07:02:54 pm
content: The unknown person in the P2238 image is me. Seehttps://www.flickr.com/photos/ultrapurple/albums/72157629533942914

author: Robert763
author_rank: Super Contributor
timestamp: November 13, 2024, 07:00:25 pm
content: There is an Argus 1 on UK ebay at the moment (Nov 2024) at a good pricedwww.ebay.co.uk/itm/226444270668The case is worth the £55 asking price. Camera looks like it mignt need adjusting though.