Anybody able to identify this mysterious Thermo (Scientific) sensor ??  - Page 1
Forum section: electronics / testgear

author: TurboTom
author_rank: Super Contributor
timestamp: October 16, 2018, 04:10:38 pm
content: Got this sensor unit for close to nothing and since it looks rather expensive, I thought I'ld rather ask here if it seems familiar to someone before I use possibly destructive methods to identify it...It consists of (what I'ld identify as) a PSU module that's permanently linked (via a RG316-like coax cable) to a sensor module. The sensor itself is contained in a (probably evacuated) stainless steel capsule that is equipped with a (probably very thin) metallic window. There's another cable coming from the sensor module that is connected via an SMB (or similar) connector to an amplifier board that was mounted in a brass shield right on top of the sensor. The PSU and the sensor interface are completely covered in polyurethane resin so there's no way to analyze them without a high risk of causing permanent damage to them. The amplifier board carries the "Thermo" label which makes me believe it's from a Thermo Scientific instrument of sorts.The sticker "KαGe" on the PSU module indicates that it could be a proportional X-ray sensor of some kind and that this assembly could originate from an X-ray fluorescense analyzer (XRF machine). But I don't think that it could be a Ge(rmanium) sensor since these are usually cooled and there's no way that the detector was cooled together with the amplifier attached to it the way I received the assembly. But of course, I'm not sure if the assemblies might have been bolted together only for shipping / storage.Anyway, I'ld be grateful for any information that may be useful finding a decision what to do with this sensor assembly and possibly getting it working again...Thanks,Thomas

author: vindoline
author_rank: Unknown
timestamp: October 16, 2018, 11:37:26 pm
content: I think you're on the right track with the x-ray hypothesis - the "KαGe" is a bit of a give away. If it's not a sensor, then it could be either a target or an optic. I believe that germanium is used for both. Other than that, I have no idea! I will say that the device probably has some exotic components/material in it and is likely very expensive and very easy to ruin. Have fun!

author: DaJMasta
author_rank: Super Contributor
timestamp: October 17, 2018, 03:58:01 am
content: Could it be some sort of infrared thermometer? Germanium is commonly used as a lens for thermal cameras, and it would explain the "Thermo" marking. Not sure about the Ka, and since it's only a single input, definitely not an imager.

author: TurboTom
author_rank: Super Contributor
timestamp: October 17, 2018, 11:08:13 am
content: I'ld rather think the window is made of beryllium since this is more or less transparent to soft x-rays. If the "Ge" on the label actually refers to germanium is unknown anyway. Considering the single supply line to the sensor / detector unit and the rather high(ish) speed amplifier design, the detector may actually be some kind of a proportional geiger tube (yet the small size surprises me - but at low energies this may actually be possible). In this case, the PSU box would contain a high voltage source to properly bias the tube. The clamping circuitry at the amplifier's input also points in this direction.I guess I've got to find out the pinout of the PSU with some common sense and some trial and error...and hope it will survive. The good thing is that all the opposing pins of the 7*2 connector are bridged and four pins are ground, so there are just five signals to identify... To tell from the capacitances at the pins, it seems there are two power inputs (probably 5V logic supply and a higher voltage (12/24V) to supply the step-up converter transformer/switch primary). The remaining three signals will have to be figured out by testing. I expect there to be one enable signal, one propotional input signal to set the output voltage and one scaled output voltage return signal to monitor the actual output voltage of the converter. It's a pity I cannot monitor the output voltage without cutting the wire...