WWII Submarine SJ Radar: USS Cod Sees in the Dark

[@USSCod]

We want to correct my interpretation of the red hash marks on our conning tower depth gage: the lower mark at 27 feet indicates bridge hatch dry, the middle mark is SJ dish dry and the upper mark is attack scope depth, which is the same depth as the SD aircraft radar.

[@jimsamoly5238]

Thanks for all the videos on USS COD. I started my 9 1/2 yr service on diesel boats on Cod in 1969.

[@jimsamoly5238]

As a 2x6

[@burncycle4621]

I watched this video and scrolled down to comment on this very issue. I see you corrected it, though. LOL.

[@tronmcconnell4465]

Thank you for the shout out regarding the scientists and engineers from the MIT Rad Lab for their radar development work. My father spent the war there, as Group Leader for the development of MTI (Moving Target Indication).

[@tonyInPA]

Bravo zulu from a USS NEW JERSEY volunteer. We all love to have fun and banter between ships, but the little things are important. The volunteers figuring out the little things…like those forgotten in documenting of SHIPALTS…are the reason these ships will keep working…and telling their stories for years to come. Keeping these systems working (when they had to operate after being underwater) is ONE thing that the surface ships don’t have to worry about 😅 Was great to tour USS MARTHA STEWART (I mean COD) two years ago, hope to come back later this month. 😊. Highly recommended for all in the Cleveland area! Beautiful boat.

[@peterharband326]

Thanks Paul. You are the Chief of the Boat. (You work too hard to be a officer) :)

[@skovner]

Just a note - electrons are not transmitted; what goes up the waveguide is electromagnetic radiation - photons, but a much longer wavelength than visible light. Today, radars can steer without moving the antenna, using phased arrays or the more recent AESA - active electronically scanned array. But the steering range is more limited, which is why modern destroyers have several of them on the superstructure.

[@bluerebel01]

Wow, I never knew you could send messages through radar. Thanks for sharing that information.

[@franklinwerren7684]

Did a little research on your SJ radar. It is in the 10 cm band which is in the Amateur Radio band. Your local hams could get it running provided the radar is only transmitting 1.5 kw maximum. The old radar was capable of 50 kw in power. DE N2JYG

[@daviddrotar410]

I live in Cleveland, OH born and raised and when growing up in grade school we had a wonderful field trip to tour the inside and outside of the USS. Cod which was such a fun informative tour of the submarine docked close to the Rock and Roll Hall of Fame and the Great Lakes Science Center. Burke Lakefront Airport is located right next to the USS. Cod. Some great tourist destinations within the city of Cleveland, OH. On a sunny summer day Lake Erie provides cool lake breezees along the lake shore and visitors may just travel a short distance to see all the cool places to visit along the Lake Erie shoreline. 😎 🎸👨‍👨‍👧‍👦☀️🌊🛥🚤⛵️🚢🛫🛬🚁📡🛰🎡🎢⚾️🏟🏈👍

[@BB12659]

When I think of how far the boats have come, I look back to World War II as the catalyst for what we see today in our boomers. Once again, great segment Paul. Thanks!

[@davidstrother496]

Thank you, Paul and USS Cod. I learned some new things. I had never heard of the ability to transmit messages with the radar, that is really cool. I had also never heard of the radar set in the periscope. Our folks were pretty smart, weren't they. Greetings from Texas.

[@petesheppard1709]

To me, what's amazing is how the developers and installers were able to pressure-proof and saltwater-proof the emitter up on the shears.

[@paulfarace9595]

Well it wasn't perfect... but it beat others.

[@petesheppard1709]

@@paulfarace9595 Indeed! Even today, the sea causes problems for sensor. In one of his WWII novels, Ed Beach noted how subs in a wolfpack could locate others by the interference of their radars. THANKS AGAIN for these videos; I grew up on WWII sub stories, but there was a lot they had to leave out to keep from bogging down the tale, but now make them much richer.

[@dearthworm]

I've watched hundreds of hours of videos about WWII submarine warfare. This the first I'm hearing about German U-boats towing kites or autogyros for target spotting.

[@roadsweeper1]

I knew of it, but from what I gather, it was rarely used. Took too long to assemble/disassemble, and if you get spotted and need to crash dive, you've pretty much got to cut it loose and lose the poor guy in it.

[@johnbeauvais3159]

They were used in the Indian Ocean, the weather conditions in the Atlantic and proliferation of warships limited their use. They're a cool concept and I would love to make a modern one to tow behind a boat or truck like the parasails.

[@skovner]

As for the German radar detectors (sounds like something you'd want in your Porsche on the Autobahn), the Germans did not think, if I remember correctly, radar with a wavelength of around 10 cm could fit on a plane, but the Allies had the cavity magnetron (find one in your microwave oven today! Actually, don't take it apart). And the Brits would tell captured UBoat crews the emissions from the radar detector were being detected. Somehow that got back to Germany and many UBoats switched it off, allowing the Allies to use the older radar sets. (I think I read this in "Most Secret War", by R.V. Jones, head of British scientific intelligence in WWII. Fascinating read I picked up at a library sale many years ago.)

[@BB12659]

Das Limpet, enough said.

[@richardvernon317]

Prototype SJ set deployed in December 1941. Production SJ sets started to roll out in June 1942, Most Sub's had them by start of 1943. 10cm Magnetron and the idea of the PPI scope given to the US by the British in September 1940.

[@wtmayhew]

A cool white paper on US submarine Radar in the pacific theater. _Radar and the American Submarine War, 1941 -1945: A Reinterpretation_ by Robert Dienesch. It is a nicely footnoted and thorough paper and very readable. My link was rejected, so just search the title and you’ll find the paper at the Canadian Nautical Research Society.

[@richardvernon317]

www.cnrs-scrn.org/northern_mariner/vol14/tnm_14_3_27-40.pdf

[@mrkeiths48]

Thanks Paul and all of the Cod crew for bringing these interesting and educational videos. Please give us a run down on each of your individual experiences with the Cod, and or the submarine service ( we probably missed the episode where you already did this). Additionally, any feelings on DBF (diesel boats forever)? I served on a nuke boat in the 80's and only have the deepest respect for all sub sailors that have served and qualified in the submarine fleet.

[@paulfarace9595]

Can't discuss DBF because I'm a civilian as is most of my crew😮. I've been with Cod 48 years so there's lots of interaction over the half century.

[@DanielsPolitics1]

Re the radar comms: The more things change, the more they stay the same. We started out directing cones of light from signal lamps, they started shining cones of radar, we now are working on lasers, and we are right back to signal lamps, which still can’t be intercepted.

[@tomtrenter3208]

We could xmit in sonar and underwater telephone using handkeys.

[@HootOwl513]

[25:45] Aircraft audible -- Starboard Quarter -- 10,000 yards. *DIVE* DIVE Dive !

[@jayp7171]

Paul, just a quick little note, saying “house of lube” might lead some people to the idea this might not be a family friendly channel LOL. But seriously my wife and we’re talking about slide rulers last night, and I was telling her how the engineers during WWII were particularly skilled considering they had paper, slide rules, and brains to figure out how to build this stuff. Kudos to MIT and all of the scientist who made all this possible, and Kudos to you for educating more generations about these things.

[@garywayne6083]

Great info - thanks!!

[@waynewolfe8817]

Have you checked the oil in the gear reducer/differential? There should be a plate on the reducer to tell you what type of oil, (90 weight, I'd guess).

[@georgeburns7251]

Very interesting.

[@madhungarian3024]

Interesting. I hadn't heard of the radar telegraph key thing. But i seem to recall from my reading that many WW2 radar technicians started out as radiomen, so they would've been quite familiar with morse code.

[@lawrenceberlinski7643]

I really like the deep dives (if you'll pardon the turn of phrase). One doesn't often get so much detail. Thank you for preserving this history.

[@scottfarnham2717]

Excellent video everyone! I'm still amazed at how they kept all that electronic equipment running in that environment. Thanks for taking good care of our Cod!

[@miguelmouta5372]

In fact because Japan didn’t have radars they lost Midway, and then the war tide changed.

[@1boortzfan]

Another great video Paul. I see why you might get the radar working to transmit but what about the boat's radio system? That would be really cool. Also the trick of using the radar to transmit a radio signal was written about by Wayne Green in a booklet he published about life on a WWII fleet boat. Wayne was the publisher of a magazine called "Amateur Radio Today." Keep up the great work.

[@gregbillman42]

much respect sir

[@AugustusTitus]

If you can capture the traces off of the other boat, it shouldn't be difficult to scopes a board to make that and inject it so the radar scops appear to work.

[@bigsarge2085]

⚓

[@crisslastname9417]

Love the T.D.C. 👍

[@kdj7337orlando]

Another very interesting video. Really like these videos on how things worked during WWII. The beatings are working as Evan is doing some great photography.

[@Foxbat1155]

Wake me up when you RADIATE and I can see the SCOPE working.

[@paulfarace9595]

😂 baseball bats or buckets of ice water ... what's your preference for a wake up call 😮😅😂?

[@lindabrashear57]

Very cool! Will you have the radar turning during the O-19 commemoration on 7/9? That's my next definite planned visit to the boat, so it would be cool to see the radar going on that occasion. Also, does being berthed next to Burke Lakefront Airport cause limits on Cod's ability to actually work the radar?

[@klepper00]

Great video guys ! Thank You !

[@nickmoore385]

A fascinating insight into the boat’s radar system. Thanks Paul and team.

[@tracyo868]

With the periscopes up did they create a blind spot? Or were they typically down when the SJ was up?

[@paulfarace9595]

Too close to be a blind spot, I'm guessing.

[@roadsweeper1]

I had no idea one could see the radar image in the attack scope. Makes sense i guess. Also, was the SJ radar telescopic or fixed? Did it retract down behind the conning tower shields when not in use to protect it?

[@paulfarace9595]

You didn't seevrhe ST readout in the periscope. You saw the return on the SJ scopes. The SJ dis is fixed. It doesn't raise or lower, like the SD aircraft radar.

[@wdcjunk]

Can you talk about under water voice communications between ships? Does that 'thing' even exist? I've seen things like this in movies but it never gets talked about so I just assume its a hollywood fabrication.

[@wdcjunk]

I'm not referring to the rescue buoy either just to clarify.

[@chrismaverick9828]

No, it exists. It was introduced in 1945 in US subs, but is based off of some tech demonstrations from 1935 Germany. In the US Navy it's called "Gertrude" for slang. There are several ways to accomplish the signal creations and reception. It's essentially a modified High Frequency Sonar set.

[@paulfarace9595]

Our Gertrude was installed in 1951. We're going to talk about it eventually.

[@tomtrenter3208]

The underwater telephone is real using both voice and keyed xmissions. "Gertrude" transmits an audio carrier wave and modulates that with voice audio. The receiving "gertrude" demodulates this signal into voice, it's basically an audio Amplitude Modulated device, or AM like a radio.

[@kilcar]

That cannot have been healthy for thelookouts or anyone on the bridge.

[@paulfarace9595]

There was a very high lookout platform on the level with the radar dish. It didn't survive to 1951. Im guessing there were health issues with the radars and the lookouts on the high platform.😮

[@johnslaughter5475]

Thank you, Paul, Great video on getting the SJ antenna rotating again. BTW, why can Cobia have a working radar and Cod can't? You mentioned the FCC, but wouldn't that affect Cobia? I thought that Jig was the phonetic letter "J" in WWII. I sure could be wrong. I wasn't born until 1950 and never learned the phonetic alphabet until the early '60s. I think I can still remember it as well as the current one. I know I've made mistakes on occasion and slipped an old letter in when giving out a license plate or some-such. I offered to donate "Silent Victory" and "I-Boat Captain" to Cod and haven't heard back.

[@paulfarace9595]

Cobia's radar runs because she has a crackerjack volunteer who commuted between Texas and Manitowoc for months of not years to rebuild her set! But he had the licenses and training to do the job. Our BZ to him, and he offered to help 20 years ago. We weren't in a position to accept that help then, but maybe we can do it someday soon.

[@johnslaughter5475]

@@paulfarace9595 Thanks, Paul. What about the books? Do you already have them?

[@robertporterfield9578]

Very informative.

[@m.hamacher7881]

German U-boats began being fitted also with "active" radar (called Funkmessortung, or FuMO) in late '42, and several iterations of these devices were fitted (all A-scope), but it was never trusted (rightfully so given Allied detection capabilities) by commanders and seldom used. U-505 tried her FuMO-30 unit as a test after letting a neutral freighter pass and she couldn't pick her up at a range that should have been possible. So there were issues there as well. The Germans were not able to bring radar to bear tactically like the US did to devastating effect. Fleet boats could develop a TDC/plot solution before even laying eyes on a target, that's HUGE. As an aside, similar to the distrust of radar, the Germans also intended active sonar to be installed on their boats, but given the general distrust of it due to detection concerns, it ended up being fitted on only a few boats (a few IXs, and VIICs).

[@DanielsPolitics1]

The IWM at Duxford has one of those German gyrocopters. They keep it in a corner of the hangar with various others signs of Nazi desperation and despair.

[@jmikronis7376]

All that, then there was the “disaster” of Mark 14 torpedo that rarely went off (detonated). It was the reason so many tests are done now.

[@earlyriser8998]

very good and in depth discussion of something I have read about but rarely seen

[@DanielsPolitics1]

Can you tell us what it would actually transmit at? I can’t find any useful details of the frequency.

[@paulfarace9595]

S band radar 2-4 GHz, the X band periscope radar (ST) 8-12 GHz.

[@tomtrenter3208]

Before ST radar was installed on our boats the man at the periscope turned a little hand-wheel lining up images in the scope. This device is called a stadometer which produced a range visually. They had some errors because the user had to guess the height of the targets mast, stack or some other object of know height. If the user made the same error guessing the height each time they did a sight the errors evened out but in the pressure of combat this wasn't so easy. Periscopes were very accurate in bearing but when using it for ranges it was kinda poor. Tracking targets you need both accurate bearings and ranges to to plot their course and speed. Radars give very accurate ranges but bearings sometimes have some errors. Active sonar is very accurate for bearings but is so- so for range depending on water conditions and how distant the target is. Passive sonar give accurate bearings only, no range. To solve the problem with getting an accurate range using a periscope the ST radar was developed into a usable unit and sent out to the fleet. As far as operation procedures I imagine the periscope operator would talk to the radar operator and tell him when to transmit and give the tracking party the range. This would probably be done at 3 minute intervals or sooner if in close to the target. The radar operator controlled the transmitter and saw the echoes most likely on the A scan. The periscope operators partner on the scope would read the bear from the bearing wheel on the periscope and pass it to the tracking party. This gave the tracking party good info to make an accurate plot. This was also VERY useful in close when making quick sights with the scope to see if the bearing and range matched up with the TDC'c computed bearing and range. If they matched then the target was on a constant course and speed, if not they had changed course and or speed and a new plot was started to solve for a new firing solution. This was where the TDC really shined because if kept a continuous electromechanical plot of Own Ship on display and all it needed was a few more bearing and ranges imputed and it would give a new target course and speed and a new firing solution which it would send to the torpeodes.

[@irishtank42]

This may be a little ahead of its time, but did the radar have a passive search function? (To those who don't know what that is, it means the radar is not radiating but is taking radiation. Therefore, you can see if someone is searching with their radar but not give away your position by sending out radiation.)

[@wfoj2]

On the Modern ships equipment for that function is present but totally different hardware / designation. See the AN/SLQ-32 or Vietnam era the AN/WLR-1. I doubt that hardware had such capability but could be wrong.

[@chrismaverick9828]

The radar really was only ever an active search system. They introduced the APR-1 receiver in '42. It was a non-directional receiver that could tell you that a radar beam was looking your way (from somewhere), the strength/intensity and the cycle/Hz of the emission. it was often used to detect enemy radar-equipped search aircraft and could help to figure out when best to dive to avoid them, though there were tricks the enemy used like changing the output strength that could result in the aircraft getting closer than desired. Dick O'Kane of the USS Tang wrote that they used it to measure and track enemy shore-based radars that covered narrow channels. They could use it to detect US subs and then vector in anti-sub forces. The Tang successfully fooled one once on the way into the patrol zone by pretending to be a fishing boat (IIRC), but had to give her all she's got to get back out as the enemy was wary of them and tried to intercept, barely being outrun by the wily ship and her valiant crew.

[@irishtank42]

Awesome thanks for the answer. People don't realize how advanced some things were in WWII. AAA guns are good examples of that.

[@paulfarace9595]

​@chrismaverick9828 this is a great example of our two-way education system that makes our channel fun!

[@chrismaverick9828]

@@irishtank42 The VT fused warhead changed everything in AA guns in terms of effectiveness. The 40mm on up had them, but the 20mm's were still just a matter of filling the empty deck-space with guns and the sky with lead.

[@danquigg8311]

How was AC electricity produced on the boats? Or, did everything operate on DC electricity?

[@paulfarace9595]

AC motor generators furnished ac power.

[@tomtrenter3208]

DC motors turned AC generators which produced 120VAC 60Hz and 115VAC 400Hz. These were called motor generators.

[@tomhenry897]

It amazes me how advance we were back then

[@waynewolfe8817]

Those electric motors only take a minimal amount of grease, one or two strokes only.

[@waynewolfe8817]

The reason for that is, as the grease pushes out of the bearing, to the inside, if it is over greased enough, it will get into the armature, and then shorts out the motor.

[@paulfarace9595]

​@@waynewolfe8817thanks 😮

[@michael-dm2bv]

115 volts dc? ❤❤❤❤🎉🎉🎉🎉

[@50craneman]

Great tour Paul. Still no depth charge indicator?

[@paulfarace9595]

Nope

[@user-kp1ei7mn3x]

It's pretty cool.

[@Ganiscol]

What always fascinated me about early RADAR is the fact that there was no electronic aid to process the signal and make it easy to read for the operator - you're getting the raw signal on the tube and have to interpret it yourself without explicit information about heading, altitude, range and speed (for air targets).

[@paulfarace9595]

Well all of those features are pretty advanced and took as much skill to develop as radar itself. Also the argument can be made that you don't want to turn over interpretation to a machine ... having the skill to interpret the returns means you avoid losing data to an algorithm.

[@scipioafricanus4328]

“Corbia; attack the garbage scow” great banter!

[@rogerhare7886]

The big radar story (told by a HYPO worker to me): Layton’s code men tracked EVERY IJN ship and Maru. Passive radar attached to lead sub w/Capt. trained in super-secret American code, led Wolfpacks to happy hunting grounds through HYPO direction. Passive radar allowed slow maneuvering known mined areas (JN25B allowed us knowledge where IJN mines were placed). A read of SS Sculpin’s fate gives clues to Captain Cromwell’s MOH: He knew this secret program and obscure American code and went down with the ship, thus saving the operation. [popular history relates his vague knowledge of Truk invasion as reason for his sacrifice] This Musician/Code man directed me to book “Double-Edged Secrets” by WH “Jaspar” Holmes. Reading between the lines of this book lays out the real Pacific sub story. All made possible by shrinking passive radar systems, HYPO directions and secret American code talk.

[@paulfarace9595]

I think you're confusing and combining several technologies... and radar by its nature can't be passive. 😮

[@rogerhare7886]

@@paulfarace9595 Passive because the “ping” doesn’t return to give away your location. Yes, a misnomer but it’s what they called it. Same as aboard WW1 USS Kingfisher (AM25) late in war but removed because ship had to move too slow for operation.

[@paulfarace9595]

​@rogerhare7886 emissions don't return to the transmitter it's not WWII-era radar!

[@joes8087]

needs an in depth video on the TDC

[@banedonrunestar5618]

The Cod crew did one when they got the TDC functional again. I forget which video exactly, but I believe it was one of the early 2024 videos.

[@paulfarace9595]

​@banedonrunestar5618 really? Hummmm.... maybe you're talking about the USS Becuna video? Ours was probably very brief. A longer one is coming.

[@nigelterry9299]

Cor! How come Corbia can radiate?

[@wfoj2]

I will reword- add some thoughts - expect more from others. I wonder IF really prohibited by FCC.- Now if not prohibited - depends on your location you might totally disrupt interfere with other systems. For the fact the COBIA has kept has the working and capable of transmitting IS totally incredible- FCC SHOULD allow them some transmission time. Massive Salute to Cobia for that capability being kept.

[@1mdragas]

@@wfoj2 The Cod is right next to an active airport (Burke Lakefront). It might interfere with the airport's electronic envelope.

[@paulfarace9595]

Cobia has a great volunteer who spent a year or more working on their radar😊 set!

[@Subpac_ww2]

Dave is a boss! Amazing to see that in motion skipper 🫡