Japanese early radars?

[MakeeLearn]

Acoustic locators in Japan: 1936

[MakeeLearn]

The Japanese Type 90 Small Detector: 1930s

[MakeeLearn]

Japanese illustration for astro combat circa 1930s.

[MakeeLearn]

Japanese Naval AAA Early War
https://weaponsandwarfare.com/2017/11/0 ... early-war/

Japan developed naval radar to a far greater extent than her Axis partners, because her fleets spent much more time in contact with enemy fleets and enemy aircraft. Unlike the Germans, the Japanese pursued both metric-wave and microwave technology. They did not develop the powerful magnetrons which made British and US microwave radar fully effective (output was typically half a kW rather than the hundreds of kW of the Western sets).

[MakeeLearn]

Japanese Antiaircraft Fire Control

Various time periods...


http://bulletpicker.com/pdf/USNTMJ-200E-30.pdf

[MakeeLearn]

Japanese soldiers with a range-finder

[MakeeLearn]

Catalog of Enemy Ordnance

Originally Published by U.S. Office of Chief of Ordnance, 1945

http://www.lonesentry.com/ordnance/tag/japanese/page/3

Stereoscopic 2 Meter Base Height Finder, Model 93

SPECIFICATIONS

Power 20 diameters
Field of view 2° 15′
Interpupillary setting 56 mm to 74 mm
Diopter adjustment +2 to -4
Limits of range measuring 400 to 20,000 yds.
Base length 2 meters
Overall length 7 ft., 5 5/8 ins.
Weight 201 lbs.
Cradle
Overall length 36 ins.
Distance between trunnions 34 11/16 ins.
Height 23 ins. (approx.)
Weight 162 lbs.
Tripod
Overall height 32 ins.
Weight 100 lb

[PaxMondo]

So, they had good theory and an early start on it, but they failed to follow up and/or realize what they had.

Example 1: Yagi antennae was Japanese invention. (1926, Professor Hidetsugu Yagi and Shintaro Uda)
Example 2: cavity magnetron was a Japanese invention. ( patented its split anode (Japan, 1927; USA, 1928), Okabe )

[Rising-Sun]

Thank you guys, been trying to modding this Hearts of Iron III. Paradox have so many things are wrong in 1936 scenario. Been working on it for months and still a lot to do.

[crsutton]

Most important thing to note about Japanese radar is that they never produced a PPI screen. You know, that round thingy with the rotating band of lights that shows little pips on the screen. This is a big deal because having radar without a PPI unit really makes it much more difficult to maintain tactical awareness. It is like the difference between listening to a ball game on the radio vs watching it on TV.

[wdolson]

Japanese commanders were also very slow to accept radar and insisted on relying on lower tech means of detection very late into the war. The Code of Bushido put an over emphasis on the spirit of the soldier being able to achieve. Using some sort of technological device that could detect enemy ships and planes beyond the range of human senses was deemed to be "cheating".

The US and UK had intense interest from top leaders and they poured a lot into R&D. They also had no qualms with giving their side every edge possible. The Germans too invested in radar, though they focused more on land and air based systems. By the time the Allies started using naval surface ship detection radar, the Kriegsmarine surface fleet wasn't leaving port much, so there was little need.

Bill

[BBfanboy]

ORIGINAL: wdolson

Japanese commanders were also very slow to accept radar and insisted on relying on lower tech means of detection very late into the war. The Code of Bushido put an over emphasis on the spirit of the soldier being able to achieve. Using some sort of technological device that could detect enemy ships and planes beyond the range of human senses was deemed to be "cheating".

The US and UK had intense interest from top leaders and they poured a lot into R&D. They also had no qualms with giving their side every edge possible. The Germans too invested in radar, though they focused more on land and air based systems. By the time the Allies started using naval surface ship detection radar, the Kriegsmarine surface fleet wasn't leaving port much, so there was little need.

Bill

In Scharnhorst's final sortie she used her (inferior) radar to try and get at a convoy from a direction the British Close Cover cruisers were not guarding, but the superior British radar enabled them to block each attempt. On the second attempt a cruiser shell (from Norfolk, IIRC) took out Scharnhorst's radar, forcing her to give up the attempt. That lack of radar played a part in her inability to detect BB Duke of York closing in on her during the RTB.

[crsutton]

ORIGINAL: BBfanboy

ORIGINAL: wdolson

Japanese commanders were also very slow to accept radar and insisted on relying on lower tech means of detection very late into the war. The Code of Bushido put an over emphasis on the spirit of the soldier being able to achieve. Using some sort of technological device that could detect enemy ships and planes beyond the range of human senses was deemed to be "cheating".

The US and UK had intense interest from top leaders and they poured a lot into R&D. They also had no qualms with giving their side every edge possible. The Germans too invested in radar, though they focused more on land and air based systems. By the time the Allies started using naval surface ship detection radar, the Kriegsmarine surface fleet wasn't leaving port much, so there was little need.

Bill

In Scharnhorst's final sortie she used her (inferior) radar to try and get at a convoy from a direction the British Close Cover cruisers were not guarding, but the superior British radar enabled them to block each attempt. On the second attempt a cruiser shell (from Norfolk, IIRC) took out Scharnhorst's radar, forcing her to give up the attempt. That lack of radar played a part in her inability to detect BB Duke of York closing in on her during the RTB.

Yes, resource allocation was always a problem in the Reich as well as Japan. They had the technological knowledge but they just did not have enough resources to follow up with it all. Plus, the Nazi industrial system was just to decentralized and fragmented. I have to laugh when people talk about Germany developing the bomb. It took a billion dollars and an incredible amount of production surplus for the US to pull it off. The Germans had neither a billion dollars or the surplus industrial capacity to work that magic.

[MakeeLearn]

(Defense of Japan 1945.pdf)

An Army NEC Tachi 1 searchlight-control radar at Muroran in 1945. This was one of the earliest fire-control radars but was not especially durable.

[MakeeLearn]

ORIGINAL: PaxMondo

So, they had good theory and an early start on it, but they failed to follow up and/or realize what they had.

Example 1: Yagi antennae was Japanese invention. (1926, Professor Hidetsugu Yagi and Shintaro Uda)
Example 2: cavity magnetron was a Japanese invention. ( patented its split anode (Japan, 1927; USA, 1928), Okabe )

There is a good foundation for improved Japanese radar in "what if" mods.

"In the late 1930s Japanese engineers led the world in development of cav- ity magnetrons for generation of microwaves and the reflec- tion experiments were quickly repeated at microwave frequen- cies. Not until a Japanese delegation visited Germany early in 1941, however, did any serious interest in radar as such emerge. The navy allocated a large sum (¥11 million) for radar work and two experimental pulse radars were demonstrated in the months immediately before Pearl Harbor, one at micro- wave frequencies."

[spence]

Most important thing to note about Japanese radar is that they never produced a PPI screen. You know, that round thingy with the rotating band of lights that shows little pips on the screen. This is a big deal because having radar without a PPI unit really makes it much more difficult to maintain tactical awareness. It is like the difference between listening to a ball game on the radio vs watching it on TV.

The PPI scope gives a tremendous assist to visualizing any tactical situation. The SG type radar of the USS Helena at the Naval Battle of Guadalcanal allowed the Captain thereof to see the US column and the dispersed character of the IJN formation at a glance (a relative bearing "God's Eye view of the battlefield similar to most wargames). Meanwhile Adm Callahan commanding the US TF on the USS San Francisco which had the more primitive SC type radar knew only the current range and bearing to one individual enemy ship at any particular instant. No doubt he had a telephone talker recording ranges and bearings as they came in and possibly somebody plotting those ranges and bearing on paper but on a dark and moonless night seeing the "God's Eye" view for himself would have definitely allowed for quicker decisions.

[rustysi]

I have to laugh when people talk about Germany developing the bomb. It took a billion dollars and an incredible amount of production surplus for the US to pull it off. The Germans had neither a billion dollars or the surplus industrial capacity to work that magic.

Yup, and a lot of that 'production surplus' had to do with electricity. Thankfully we had the TVA, hence Hanford and Oak Ridge. Supposedly Speer had asked someone in his ministry what it would take to develop the 'bomb'. When informed he was supposed to have said that diverting that many resources to the project would lose Germany the war.

[Zorch]

ORIGINAL: rustysi

I have to laugh when people talk about Germany developing the bomb. It took a billion dollars and an incredible amount of production surplus for the US to pull it off. The Germans had neither a billion dollars or the surplus industrial capacity to work that magic.

Yup, and a lot of that 'production surplus' had to do with electricity. Thankfully we had the TVA, hence Hanford and Oak Ridge. Supposedly Speer had asked someone in his ministry what it would take to develop the 'bomb'. When informed he was supposed to have said that diverting that many resources to the project would lose Germany the war.

The greatest achievement of allied scientists was persuading the US government to invest the resources needed to build the bomb.

[PaxMondo]

ORIGINAL: MakeeLearn

ORIGINAL: PaxMondo

So, they had good theory and an early start on it, but they failed to follow up and/or realize what they had.

Example 1: Yagi antennae was Japanese invention. (1926, Professor Hidetsugu Yagi and Shintaro Uda)
Example 2: cavity magnetron was a Japanese invention. ( patented its split anode (Japan, 1927; USA, 1928), Okabe )

There is a good foundation for improved Japanese radar in "what if" mods.

"In the late 1930s Japanese engineers led the world in development of cav- ity magnetrons for generation of microwaves and the reflec- tion experiments were quickly repeated at microwave frequen- cies. Not until a Japanese delegation visited Germany early in 1941, however, did any serious interest in radar as such emerge. The navy allocated a large sum (¥11 million) for radar work and two experimental pulse radars were demonstrated in the months immediately before Pearl Harbor, one at micro- wave frequencies."

Exactly.

[crsutton]

ORIGINAL: PaxMondo

ORIGINAL: MakeeLearn

ORIGINAL: PaxMondo

So, they had good theory and an early start on it, but they failed to follow up and/or realize what they had.

Example 1: Yagi antennae was Japanese invention. (1926, Professor Hidetsugu Yagi and Shintaro Uda)
Example 2: cavity magnetron was a Japanese invention. ( patented its split anode (Japan, 1927; USA, 1928), Okabe )

There is a good foundation for improved Japanese radar in "what if" mods.

"In the late 1930s Japanese engineers led the world in development of cav- ity magnetrons for generation of microwaves and the reflec- tion experiments were quickly repeated at microwave frequen- cies. Not until a Japanese delegation visited Germany early in 1941, however, did any serious interest in radar as such emerge. The navy allocated a large sum (¥11 million) for radar work and two experimental pulse radars were demonstrated in the months immediately before Pearl Harbor, one at micro- wave frequencies."

Exactly.

The weakness was not just in Japanese industry but in their educational system. There were just not enough college educated people in Japan to support this kind of industry. This was not something that could be corrected in a few years. If they wanted to build radars it would have meant robbing Peter to pay Paul...Something else would have suffered as a result.