Keeping the water out of the joints between the aerial feeders and the Aerials on the CH stations was a major problem in 1940, not only did it cause loss of power and receiver sensitivity, it also caused errors in bearing and height finding.

Thank you for that, Mr G. I didn't know that.

What did it do? Did it shield the wire from radio wave interference (intrusion)? Like the shielding that's woven into modern spark plug wires that keeps it in, in it's case, so it doesn't make the radio in your car hum? In older cars they had the sheet metal covers that the plug wires were routed through to keep it from happening that everyone took off and threw away and replaced with shielded wires as soon as you could buy them as a replacement set because it was such a pain to take apart. In modern coaxial video wire isn't there a layer of some kind of foil wrapped around everything under the covering that does that same thing? It's a shielding?

@@dukecraig2402 The polythene is the dielectric in the coaxial feeder. In a coax the radio energy is not on the wires but between them in the dielectric, so it is important that that dielectric is low loss. The wires allow the termination (boundary conditions) of the fields in the dielectric so it stays inside the coax and goes where the coax goes, until it is released by the antenna. Polythene has very good low loss at radio frequencies. The alternative is to use an open twin wire feeder because dry air is an excellent dielectric but open wire feeders have a whole host of problems when used in restricted spaces. A coax arrangement provides very good shielding with the outer conductor surrounding the fields . The bending radius of the coax is also important so it is possible to install in restricted spaces. Further developments replaced the solid polythene dielectric with ribbed polythene (that looks like a star in cross section). The polythene air mixture has even better low loss performance but still provided the necessary mechanical structure to keep the inner wire centred and hold out the outer mesh at the correct spacing. Spacing between inner and outer is critical in a coax to maintain the impedance of the coax. If it starts to vary along the coax one starts to get reflections of energy coming back towards the transmitter. In the case of spark plugs you are sending an electrical signal along the wire rather than radio energy between the wires as one does in an rf (radio frequency) feeder system. But because the spark voltage is high and the pulses have sharp edges they contain radio frequencies. To prevent them leaking out too much shielded plug leads are used . It is little appreciated that in an rf feeder system the energy is already a radio wave (constrained by the feeder system) once it leaves the transmitter and the antenna is a matching device that launches the energy into space. The incorrect, but widespread, understanding is that an electrical signal in the form of volts and amps is converted into an electromagnetic field when it reaches the antenna. The wires in an rf feeder system do not carry the energy they simply direct where it goes. Rather like a train on a track.

@@dukecraig2402 Reduced/controlled transmission line losses between the radio gear and the antenna, particularly at higher frequencies.

Fortunately, they did 😉

And it was all done without transistors and digital processing. 👍

I recommend the book "The Invention That Changed the World: How a Small Group of Radar Pioneers Won the Second World War and Launched a Technical Revolution"

I've had it on DVD for 20 years!!!

It's not. Tom Owens uploaded it 2 years ago. kzfaq.info/get/bejne/d9JibKSqm87ZcoU.html

It was also published 2 years ago by Tom Owens. Exactly the same film!

Except that it has been altered. Great find, like finding a fake Sunflowers painting. It may look "nice" but you know it isn't real. Actually, a good one of those cheap would be cool, videos altered by people on youtube, not cool.

God bless him 🙏

I hope that your Father enjoys this film. Bless him at 103 not out! 😊

I hope your dad found it interesting. Please pass on my sincere thanks to him for his contribution to our freedom. My own dad, now 96 and in poor health, was a humble infantryman in the far east. However his elder brother, my uncle Peter, was a pilot in Coastal Command and used radar for detecting German U-boats.

Did he like the film?

September, 2023. I am now reading Night Fighter. Its about Rawnsley And Robert Wright. Wight was his radar intercept crew member. Published 1957, by Collins.

Well not entirely. American Ship radar was the very first radar. And the American ship radar was ahead in capability to British ship radar throughout the war. But British ground based radar including airplane radar by the British was ahead till about 1944. I refer you to Robert Morris Page, The Development of Radar, 1962. There was considerable cross Atlantic cooperation by 1941.

By first, I mean the first system that had active an real world application. In this case, it was installed in a ship, to avoid collision s. Long before the ground based British systems.

The British paid us back by giving the Commies all of the latest Western jet engine technology. That's why we didn't want the British to have the bomb, for fear they would sell it to Russia. Those 'rust-bucket' destroyers helped assure that the millions of tons of food, metals, planes, trucks, guns and gasoline made it to you so you could even stay in the war.

And a cherry on top also!

Here's a wild fact for you, when Locust are in a swarm they all beat their wings in unison. I was watching a thing on The Discovery Channel one day about insects and they pointed that out along with showing high speed film slowed down so you can see it, talk about something freaky looking, millions of them all beating their wings exactly the same, I can't remember if the scientist's had an explanation or not it's been so long ago that I watched it, probably back in the 90's but I'll never forget that image.

The things that you can learn from reading KZfaq comments! Amazing!

My electronics engineer father worked on British WW2 in New Zealand, far away from enemy reception.

TP 8329 TP 8329 TP 8329

I bet you would adore the book, Night Fighter, by C. F. Rawnsley .and Robert Wright. It details the importance of your fathers work.

@raywhitehead730 Many thanks for the recommendation Ray, I'll look out for a copy.

Defford was the location of the airfield where TRE operated their aircraft from. The TRE labs were at Malvern college 6 Miles away.

Many years ago now, when Microsoft were trying to out show Oracle they released a global visualisation that they called TerraServer (sort of a very early google earth) - their big DB was called SQLServer. I was working in Malvern (TRE but not for them, NHS instead) at the time. Microsoft were being cheapskates and had bought all of their satelite images from what had just stopped being the Soviet Union. One could identify areas of interest by seeing which sites had been photographed on the Soviet Satelites. The scan over Birmingham went as far as TRE and stopped. Now it may be they didn't wan't to release the shots over Hereford but I for one, found a certain amount of schadenfreude in the thought that put me and my family pretty much to ground zero for an SS20. When I casually mentioned it to my wife she insisted we moved. After all, one can allways avoid 3*3MT+ warheads by following the USN dictum, "the only defence against an atomic atack is to be somewhere else.". It was a fascinating example of inferred intelligence.

I'm almost certain it's John Snagge.

Dunkirk, England

and a few more to boot. I too had to check and see which little hamlet bore the name of the rescue. to discover that there were 8 of them in the UK.

Also a farm in Northumberland🙂

Alertness and uptake essential, it was shown on maps !

I believe that the Aussies have an OTH radar possibly still operational today.

Thank you, I got the Bach, but couldn't remember the title. I DO think there is a bit of strange humour there!

Yep, you'd clean off those copper buttons inside of them with a pencil eraser and all of the sudden a radio set that had transmitting and receiving issues would clear up and work like new. I can't remember the nomenclature of the components but in the armored vehicle I was a crewmember on we had the big unit that was a receiver/transmitter and the ox, auxiliary receiver only, and the Vincent (but we're not allowed to talk about that one, although by now you can probably but those things in Army/Navy surplus stores and Ebay😅😅).

Me too !!! THANK YOU - and Subscribed.

Very great care was taken to supplement the narrated explanations with visual cues. These kind of videos are sorely lacking in the education field nowaday, as a teacher I still used the first series of "BBC Connections" to teach History of Technology in a middle school.

Lee kuan yew

I have & read the same books but this endeavor is really great showing the development and time line for each problem & solution.

That's all the original texture and detail there is. The scale provided by digital archives and old dvds etc is the original, and that's about 400 per cent less than modern televisions. I'm tinkering with digital upscaling to enhance what's there and remove the pixelation / blurriness of automatic interpolation, remove lens flicker and film vibration. It's still a learning process for me.

must throw in my tuppence worth here; truly excellent production work; brings the sense and feel of the original footage to life. How much archive material there must be out there, which we have only seen in worn-out prints! Time does a blink, and we are at any point in the last century.... best regards@@ArmouredCarriers

and also shows very clearly the culture of innovation and excellence in this country which set Britain, not simply ahead of the yanks, or the enemy, but in a league of her own in so many fields: jet engines and all the rest. Everyone simply filling in the gaps, ever since.

I assumed it to mean sensitivity.

In direction finding you have to resolve if a signal is on the forward bearing or the back bearing. Sense answers that question. Later systems did not need to resolve sense as reflectors behind antennas quenched the back beam lobe that was in the antenna radiation pattern of the early more basic antenna systems.

@@twotone3070 thanks....that makes sense .....important to determine in the early days of this new method 🙏🙏👍👍

@@Mr_G977 THANKS....when they mentioned that it went right over my head .....t y 🙏🙏👍👍you teach....I learn

Your clock seems off.

It may seem “old and very primitive” now but it was cutting edge then. You must give enormous credit to the pioneers who had a limited range of test equipment at their disposal and were working from first principles. The system engineers of today are “standing on the shoulders” of these extremely talented electronic engineers.

@robertdonnell8114 All the Digital stuff does is replace a load of Analogue electronics which did its job in the past. plus a load of WAAF moving plots on a table and a bloke trying to filter out all of the crap. The basic physics of how it all worked is the same today.

So learn the science and the tech ... problem solved.

No-one stated that it was invented in Britain, it was known that the Germans had their secrets too. The wreck of the Graf Spee was examined immediately and the radar antennas measured to determine the exact frequencies in use.

The first patent was made by a German in about 1906-8 using a horn antenna, no amplification, a short range of about 2-300m at best and was intended to stop ships colliding in obscured visibility. Radio was just making its first major public appearance and no-one was interested in such obscure stuff. The patent lapsed as it was not extended.

The Royal Marines conducted a raid on German Radar station on the French Coast to steal parts from the German Radar .which were found to be superior. It was being developed all around the World .As with alot of science.

We didn't invent it as such, but before the war, scientific papers were read widely, it only took a few people to understand the potential. The British developed RDF which became RADAR, the Germans developed their versions as did the U.S. The game changer (as far as I understand) was the cavity magnetron which enabled equipment to be smaller and more powerful. The British gave this to the Americans and they won the war for us. So thanks America! Appreciated.

Hiya. These sorts of things (fortunately now out of copyright) can be found scattered around all over the place, from DVD collections to digital archives. Mostly it's a matter of luck and persistence. I've published a few other original radar presentations on my channel. Others include the experience of vets with radar - particularly the ones on Sunda Strait and Swordfish v Bismarck, if you're interested in checking them out.

@@ArmouredCarriers Are you saying that the Swordfish that went after the Bismarck had radar?

Yes. Watch these to hear the pilots talk about what they had, and what they did, in their attacks on Bismarck: kzfaq.info/get/bejne/na6nfr2JmrnQnH0.html kzfaq.info/get/bejne/bsyhlJx21Jq5fGQ.html @@user-mn4us7jk5j

Ofcourse they did, at least some of them. Probably at least the flight leaders for finding the damn thing. ASV Mark II alone was produced in 58.000 pieces according to Wiki, and for once, this number is believable. The Americans build around 55.000 units of ASB-1 radar, which is a tad similar, if somewhat better than ASV Mark II. @@user-mn4us7jk5j

So basically it's a bit like when I find some old magazines or piece of tech: you recognize its value while other do not 🙂@@ArmouredCarriers

Sonar was not discovered but invented and not in Canada

What about WW1 ASDIC? Lord Rutherford worked on that in Manchester and Cambridge

Of course mighty Canada had to get into the story somewhere,lol😂 what would the UK have done without Canada forever blowing its trumpet.

Not if it is made for internal purposes. New recruits back then were starting from a very very low base (very few films or novels depicted radar for example).

But you say it was made post-war, It has been since de-classified has it?@@ArmouredCarriers

@@petefluffy7420 It was compiled in 1946 out of training films made during the war. Most of the last WW2 "secret" designations were lifted about 1995. Only the most sensitive (read political) material remains classified.

@@ArmouredCarriers OMG, 50 years after the event! Huge amount of time. The only real need after '45 might have been the cavity magnetron - essential for very short wavelengths. cheers

@@petefluffy7420 Up to 50. There were different grades of classification. Each carried a different duration.

It was a mashup of wartime training films, produced as an internal history of the war. I'd love to find those original films. Usually, in the 1930s and 40s, training films were for "introductory" sessions, providing an overview and context. Classrooms went on to convey the detail. It's the same for US WW2 training films.

@@ArmouredCarriersAt least these films did not have the violin-heavy, cheesy soundtracks of the US training films.

Please ignore this comment.

No worries. I thought exactly the same thing when I first heard it!