Comments by "Sar Jim" (@sarjim4381) on "Ballester-Molina Pistols from German Pocket Battleship Armor?" video.

  1.  @ramjb  I don't know how I ended up on such an old video, but I've been studying naval history as a hobby for about 60 years now. My other hobby is amateur radio, for with I hold an extra class license. I take particular interest in radar history. and the technical aspects of radar. The Graf Spee was equipped in Fumo-22 radar, not Seetakt. That radar set was on Deutschland, and both ships were used as sort of test beds for each type of radar. The Fumo 22 could have been used for gun laying, but the radar only had better than 50 meter circular probability of error out to about 8 kilometers, and German optical rangefinder had similar results out to about 14 kilometers in clear weather. The Kriegsmarine was interested in radar only for surface search and range estimation in 1939, so Graf Spee's gunnery accuracy was the result of superior German optics and crew training, not radar. The Admiralty actually did display a keen interest in the radar on the Graf Spee, and sent an experienced radar engineer to the River Plate to inspect the radar and electronic systems that remained. Unfortunately, his report has never surfaced. If and when it does, it will answer a lot of questions about exactly what kind of radar the Graf Spee actually had. Photos of the relatively small mattress radar antenna on the AGS had the British worried that Germans had a working microwave radar or, even more alarming, had perfected the cavity magnetron the British were working on. What they did find was the Fumo-22 operated at 600 MHz, a far higher frequency than the radars in use by British warships at the time, which operated in the 43-75 MHz range. The British were unaware that the Germans had developed an Ultra High Frequency (UHF) radar, and the knowledge gained from the Graf Spee allowed the British to develop jammers in only a few months. The British Type 79 operated at 43 MHz. Since higher frequencies required much higher power input, and the transmitting tubes of the day were incapable of high power inputs, the Fumo-22, with an input of only about 150 watts, had a range of about 20 kilometers on a good day, and usually about half that. The ranging when a target was located was far more accurate than a Type 79, but it was not far enough out to make it practical for any kind of radar gun control. However, the Type 79 operated at 20 kilowatts, so it could locate ship size targets out to an average of 60 kilometers. It was a tradeoff between range and accuracy in 1939, but the problem was solved with the British perfection of the cavity magnetron and the type 271 radar in 1941. The Germans never even came close to catching up after that.
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