LNAs and Temperatures

studio1930

but it goes to 11
Premium Plus
Lifetime Premium
Corgi Lovers
Advanced User
Joined
Dec 4, 2016
Messages
1,234
Reaction score
1,927
Location
Kansas City Area
How are LNAs affected by temperature? For example, how is a remote mount Radenso RC-M or Net Radar affected in the winter vs summer (assumed mounted outside the vehicle)? Do remote antennas (or regular detectors for that matter) adjust their readings according to an internal (board) temperature?
 

FWGuy

Learning to Fly
Beginner User
Joined
May 3, 2017
Messages
1,218
Reaction score
1,292
Location
Ellicott City, MD
Studio1930 -

All electronic components come with a temperature rating from the manufacturer. There are three standard temperature ranges offered by semiconductor companies - commercial, industrial and military. The manufacturers guarantee the part will operate within the specifications given in the datasheet over the temperature range. The three temperature ranges are:

Commercial - 0 degrees to 70 degrees Celsuis.
Industrial - -40 degrees Celsuis to +85 degrees Celsuis
Military - -55 to +125 degrees Celsuis.

Obviously, something like your flat screen TV should be fine with commercial temperature range parts as long as you've got the TV mounted somewhere inside.

Almost all devices intended to operate in an automotive environment use Industrial temperature range parts. This covers harsh conditions encountered in automobile passenger cabins. Think about being parked in the sunlight in Arizona in the summer time or overnight in Alaska in the wintertime. That's quite a range to guarantee proper operation over.

Just for reference, there is a group called Society of Automotive Engineers (SAE) that publish specs and guidelines for anything automotive related. Their recommendations say that the passenger cabin of a car can vary from -30 up to +160 (Fahrenheit) depending upon the location and time of the year. The initials SAE may be familiar to you if you buy oil. Oil has an SAE approval rating marked on the pints/cans/etc. So you'll see something like SAE 5w-30 for motor oil weight.

Anyway, the hw designers pay attention to this and a dozen other details when choosing parts for devices they design. And it should go without saying that the chain is only as strong as it's weakest link. If the hw designer for a RD chose one part that wasn't rated for the temperature range the RD encounters, the RD would fail in some way. All the parts must be chosen to survive the temperatures that will be encountered.

So, your external (installed) systems should be just fine. Designers sometimes make mistakes but choosing a part with too small a temperature range would cause a slew of problems when the seasons changed. No engineer worth the title would make such a mistake.

Also - almost all detectors will quote an operating range. I'm sure you should be able to find it for the system you're thinking of installing.

Dan
 

PointerCone

M3 Kng
Premium Plus
Lifetime Premium
Advanced User
Joined
Aug 5, 2011
Messages
22,362
Reaction score
22,702
@FWGuy just like to know if Veil is Mil-Spec as that is how VG advertises it?? :)
 

FWGuy

Learning to Fly
Beginner User
Joined
May 3, 2017
Messages
1,218
Reaction score
1,292
Location
Ellicott City, MD
@FWGuy just like to know if Veil is Mil-Spec as that is how VG advertises it?? :)

That's an interesting question. Honestly, I don't know because there's difference between electronic components ("chips") and chemical formulations (what Veil is).

@cihkal - we need your expertise please.....PC - cihkal is a CHE, a chemical engineer. He's far more qualified than I to talk about a chemical formulation (Veil) and it's response to temperature.

What I can tell you is only about electronics parts. I only know about a particular electronics parts temperature performance because that information is given in a document called a "datasheet". All electronic parts come with this document called a datasheet. The manufacturer provides this datasheet for each part and the datasheet specifies all the relevant operating characteristics for the part. Think of a document for a gasoline engine that specified things like bhp at what rpm, torque at what rpm, what octane fuel it needed, what sized clutch would mate to it's flywheel, etc. You get the idea. The datasheet specifies anything and everything the buyer would care to know about the product he's purchasing.

For an electronics component, whether an LNA or a laser sensor or an OLED display, the datasheet provide the all the necessary information - i.e. - what the engineer needs to know to use the part properly.

Chemicals or chemically based products are a bit different and out of my league. It's certainly possible Veil's product has been certified to work through some temperature range and I'm sure he can tell you what that is.

Let's hope cihkal can explain better because my explanation is pretty poor :(

Dan
 

InsipidMonkey

Essential Monkey
ModSec
Premium Plus
Lifetime Premium
Corgi Lovers
Advanced User
Joined
Mar 22, 2017
Messages
8,147
Reaction score
18,995
Location
New England
How are LNAs affected by temperature? For example, how is a remote mount Radenso RC-M or Net Radar affected in the winter vs summer (assumed mounted outside the vehicle)? Do remote antennas (or regular detectors for that matter) adjust their readings according to an internal (board) temperature?

Here are the Digikey results and datasheets for a number of K and Ka band LNAs:
https://www.digikey.com/short/qtmt0w

In short, all are at least industrial rated as Dan mentioned above, and gain and noise figures change minimally with temperature (and have built-in temperature compensation).

@FWGuy correct me if I'm wrong, but I believe they are like TCXOs in that they have a "heater" built in to maintain a constant temperature regardless of operating environment.
 

cihkal

No substitute for [actual] intelligence 🇺🇸
Premium Plus
Lifetime Premium
Corgi Lovers
Advanced User
Joined
Apr 21, 2014
Messages
4,410
Reaction score
8,748
That's an interesting question. Honestly, I don't know because there's difference between electronic components ("chips") and chemical formulations (what Veil is).

@cihkal - we need your expertise please.....PC - cihkal is a CHE, a chemical engineer. He's far more qualified than I to talk about a chemical formulation (Veil) and it's response to temperature.

What I can tell you is only about electronics parts. I only know about a particular electronics parts temperature performance because that information is given in a document called a "datasheet". All electronic parts come with this document called a datasheet. The manufacturer provides this datasheet for each part and the datasheet specifies all the relevant operating characteristics for the part. Think of a document for a gasoline engine that specified things like bhp at what rpm, torque at what rpm, what octane fuel it needed, what sized clutch would mate to it's flywheel, etc. You get the idea. The datasheet specifies anything and everything the buyer would care to know about the product he's purchasing.

For an electronics component, whether an LNA or a laser sensor or an OLED display, the datasheet provide the all the necessary information - i.e. - what the engineer needs to know to use the part properly.

Chemicals or chemically based products are a bit different and out of my league. It's certainly possible Veil's product has been certified to work through some temperature range and I'm sure he can tell you what that is.

Let's hope cihkal can explain better because my explanation is pretty poor :(

Dan

It just so happens I am a chemical engineer and I do work for an automotive coatings company :p Ah yes, the infamous VEIL coating. As for using VEIL I have no experience and have never seen the coating in person. I understand that VEIL may have been an organic solvent based coating early on and is now a waterborne coating. I think they've had challenges with the application of VEIL now that it's waterborne but this looks to have been improved a bit. On the website it lists it as a "water-borne transparent acrylic latex polymer coating" which likely really means it's a thermoset or thermoplastic acrylic emulsion letdown further with a water/solvent mixture, maybe a rheology enhancer, and some other additives. That of which I'm not really sure. I suspect the emulsion is something along the lines of a random free radical polymerization process which leaves you with an emulsion that consists of micelles containing acrylate polymers. This is where the name latex acrylic came from.

Anywho, I would not be concerned with the performance of the coating in various temperatures and if we had access to the SDS we could use this as a reference to some degree. My actual concern is the application of the coating both in the film thickness and temperature at which it is applied. I would also be concerned with mechanical wear too. As to why I'm not too concerned with the performance whether it's cold or hot is really based on what I believe the working principle is behind VEIL. I suspect that VEIL is an anti-reflective coating (https://en.wikipedia.org/wiki/Anti-reflective_coating) playing games with the refractive index of it and the material it is applied to known as the substrate. It is also important how thick the film is. This is more of a physics based problem along with polymer chemistry/coatings manufacturing. To make a long story short I believe he's trying to use the same principles that are applied to make the lenses on my glasses "anti-glare". Do I think his product works really well? Probably not in most cases because there doesn't seem to be much science behind the application of the coating. Also, he likely has a tolling manufacturer and someone to package VEIL. Not cheap so I doubt this is a really "fancy" system.

If I ever got my hands on VEIL I would be inclined to measure the refractive index, run a solids test, measure water content, possibly run it through a GC depending on the water content, run it though the laser defraction particle size analyzer, maybe pass it through the GPC to see if I can get any hint of it being cross-linked (possibly a thermoset acrylic), and last but not least visit my buddy in the lab who could use the fourier-transfrom spectrometer to get a good hint of what VEIL is actually made of beyond an organic/inorganic solvent blend. I'm sure Bob will not be enthusiastic to read this, but I make no claims of intending to make an attempt to reverse engineer his product.

I'm apt to ensure my company could make something like VEIL large scale and apply knowledge of chemical engineering unit operations to design a system that could do so if we weren't able to already. A PD (paint/coating development) chemist or R&D chemist would be better suited to comment on some of the specifics of properly applying VEIL and its sensitivity to temperature. I don't believe temperature is the point of concern though during normal use after it is properly applied. As to any ratings or being designed in accordance of a certain spec who knows.. I'd have to do a bit more research. I wouldn't be surprised if that is just a claim having an idea on how VG works.
 
Last edited:

studio1930

but it goes to 11
Premium Plus
Lifetime Premium
Corgi Lovers
Advanced User
Joined
Dec 4, 2016
Messages
1,234
Reaction score
1,927
Location
Kansas City Area
I was curious if the detector introduced more nose via the LNA when hot vs cold. Basically a reduction in performance when hot or very cold. I was not as concerned about failure of the components. Wonder if anyone has tested this.

Posted from my Nexus 6P using the RDF Mobile App!
 

patscogs

-NNJCTG-
Premium Member
Advanced User
Joined
Jun 11, 2017
Messages
1,105
Reaction score
1,072
Location
New York
It just so happens I am a chemical engineer and I do work for an automotive coatings company :p Ah yes, the infamous VEIL coating. As for using VEIL I have no experience and have never seen the coating in person. I understand that VEIL may have been an organic solvent based coating early on and is now a waterborne coating. I think they've had challenges with the application of VEIL now that it's waterborne but this looks to have been improved a bit. On the website it lists it as a "water-borne transparent acrylic latex polymer coating" which likely really means it's a thermoset or thermoplastic acrylic emulsion letdown further with a water/solvent mixture, maybe a rheology enhancer, and some other additives. That of which I'm not really sure. I suspect the emulsion is something along the lines of a random free radical polymerization process which leaves you with an emulsion that consists of micelles containing acrylate polymers. This is where the name latex acrylic came from.

Anywho, I would not be concerned with the performance of the coating in various temperatures and if we had access to the SDS we could use this as a reference to some degree. My actual concern is the application of the coating both in the film thickness and temperature at which it is applied. I would also be concerned with mechanical wear too. As to why I'm not too concerned with the performance whether it's cold or hot is really based on what I believe the working principle is behind VEIL. I suspect that VEIL is an anti-reflective coating (https://en.wikipedia.org/wiki/Anti-reflective_coating) playing games with the refractive index of it and the material it is applied to known as the substrate. It is also important how thick the film is. This is more of a physics based problem along with polymer chemistry/coatings manufacturing. To make a long story short I believe he's trying to use the same principles that are applied to make the lenses on my glasses "anti-glare". Do I think his product works really well? Probably not in most cases because there doesn't seem to be much science behind the application of the coating. Also, he likely has a tolling manufacturer and someone to package VEIL. Not cheap so I doubt this is a really "fancy" system.

If I ever got my hands on VEIL I would be inclined to measure the refractive index, run a solids test, measure water content, possibly run it through a GC depending on the water content, run it though the laser defraction particle size analyzer, maybe pass it through the GPC to see if I can get any hint of it being cross-linked (possibly a thermoset acrylic), and last but not least visit my buddy in the lab who could use the fourier-transfrom spectrometer to get a good hint of what VEIL is actually made of beyond an organic/inorganic solvent blend. I'm sure Bob will not be enthusiastic to read this, but I make no claims of intending to make an attempt to reverse engineer his product.

I'm apt to ensure my company could make something like VEIL large scale and apply knowledge of chemical engineering unit operations to design a system that could do so if we weren't able to already. A PD (paint/coating development) chemist or R&D chemist would be better suited to comment on some of the specifics of properly applying VEIL and its sensitivity to temperature. I don't believe temperature is the point of concern though during normal use after it is properly applied. As to any ratings or being designed in accordance of a certain spec who knows.. I'd have to do a bit more research. I wouldn't be surprised if that is just a claim having an idea on how VG works.

it would take me a day to go through and look up every word I don't understand - but, since this guy is such a jerk off I wouldn't mind throwing in to buy a container have an actual lab tell everyone in the world that veil - his prized and overpriced product - is useless garbage... I know you have better things to do with your time (like blow your nose) but maybe a test or two would even be enough to shed some light on his snake oil

--- Post updated ---

I was curious if the detector introduced more nose via the LNA when hot vs cold. Basically a reduction in performance when hot or very cold. I was not as concerned about failure of the components. Wonder if anyone has tested this.

Posted from my Nexus 6P using the RDF Mobile App!

I doubt BRD would sell NetRadar under his name if it didn't work correctly in any temperature you would encounter - as we all see, reputation is everything ... I know you're specifically asking about performance, but I would't sweat it for a second
 

FWGuy

Learning to Fly
Beginner User
Joined
May 3, 2017
Messages
1,218
Reaction score
1,292
Location
Ellicott City, MD
I was curious if the detector introduced more nose via the LNA when hot vs cold. Basically a reduction in performance when hot or very cold. I was not as concerned about failure of the components. Wonder if anyone has tested this.

Posted from my Nexus 6P using the RDF Mobile App!

Temperature does influence noise but practically speaking, the effect is minimal and compensated for by the circuit designers so there's almost nothing noticeable.

Here are the Digikey results and datasheets for a number of K and Ka band LNAs:
https://www.digikey.com/short/qtmt0w

In short, all are at least industrial rated as Dan mentioned above, and gain and noise figures change minimally with temperature (and have built-in temperature compensation).

@FWGuy correct me if I'm wrong, but I believe they are like TCXOs in that they have a "heater" built in to maintain a constant temperature regardless of operating environment.

Certainly this is done at a circuit level. That's what Uniden is doing. For individual components, sometimes the size of a TCXO prohibits it's use but circuit and chip designers have other methods at their disposal.

Dan
 

Freebird

Poking the bears.
Premium Plus
Lifetime Premium
Advanced User
Joined
Nov 3, 2011
Messages
4,734
Reaction score
8,493
I was curious if the detector introduced more nose via the LNA when hot vs cold. Basically a reduction in performance when hot or very cold. I was not as concerned about failure of the components. Wonder if anyone has tested this.

Posted from my Nexus 6P using the RDF Mobile App!

I remember reading a test somewhere that showed Rd's do lose performance when hot (like summer on dash hot) but no loss in performance in cold weather.

Here is a older post from @Nine_C1 that sheds more light on the subject.

Extreme heat will shorten the lifespan of any electronic component and certainly degrade their performance over a period of time before ending up in complete failure. Dielectric capacitors are particularly prone to failure if left to bake on your dashboard or windshield repeatedly.

Some extremely sensitive components, like the LNA's in the M3 antenna, can abide temperatures as high as 185 degrees in storage. However........if you power the unit on at this temperature you will fry the device!

No immediate damage will be done to your detector provided you avoid operating it at extreme temperatures..........below -4 or above +158 degrees Fahrenheit. But operating your detector anywhere close to these limits on a regular basis will degrade performance and lead to failure in a relatively short period of time.

The number one enemy of any densely packaged microelectronic device is the effect of Thermal Cyles on the numerous solder connections between the SMT devices and printed circuit board. Heat causes expansion while Cold causes contraction. Since the solder, printed circuit board lands, and actual components themselves are composed of different metal alloys, they expand and contract at different rates. So repeated Thermal Cycles over broad temperature ranges can eventually lead to microscopic cracks in these solder joints. I think the joints between the horn and microstrip are particulary prone to this problem due to the size of the horn........alot of metal in the horn and therefore alot of expansion and contraction.

So......any RD is just like us.......born to get old and die eventually!
93b3e0bae0393abb2d294dd3399bb910.gif
How we slow this process down is by limiting the amount of temperature swing of each thermal cycle as much as possible. No leaving the detector to freeze or bake in a parked car!
93b3e0bae0393abb2d294dd3399bb910.gif
 

InsipidMonkey

Essential Monkey
ModSec
Premium Plus
Lifetime Premium
Corgi Lovers
Advanced User
Joined
Mar 22, 2017
Messages
8,147
Reaction score
18,995
Location
New England
I was curious if the detector introduced more nose via the LNA when hot vs cold. Basically a reduction in performance when hot or very cold. I was not as concerned about failure of the components. Wonder if anyone has tested this.

Yes, as would be expected, higher temperature introduces more noise (eg about 2dB higher noise figure at +85C vs -40C), and lowers the gain (eg about -3dB at +85C vs -40C). Note these are pretty extreme temperature ranges, and under real-world conditions noise figure and gain wouldn't vary that much.

Here are a few representative figures from the LNA datasheets I linked to:

upload_2017-10-27_11-23-23.png


upload_2017-10-27_11-23-48.png
 

FWGuy

Learning to Fly
Beginner User
Joined
May 3, 2017
Messages
1,218
Reaction score
1,292
Location
Ellicott City, MD
Good points guys. I stand corrected. I've never worked with LNA's but the graphs from the datasheets that InsipidMonkey is showing are unmistakable. There does appear to be a 2-3 dB change in gain for a swing of 120 degrees Celsuis. Obviously, in reality, the user isn't going to see such a swing because they won't see such a temperature change.

And Freebirds post is completely correct. I posted something about this on Escort's forums a while back -

http://escortradarforum.com/forums/showthread.php?t=15279&highlight=Temperature+Electronics

Thermal cycles are the enemy for most electronics and the thermal cycles are very pronounced in automotive environments.

Dan
 

Discord Server

Latest threads

Forum statistics

Threads
95,260
Messages
1,450,030
Members
24,409
Latest member
Deags
Top