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  • billyd
    Lieutenant, Junior Grade
    • Feb 2024
    • 27

    #16
    Hi everyone this is my first post to the forums, but I am not new to rc controlled vehicles. Has anyone tried TBS crossfire in a submarine? It operates at 915 Mhz and will also automatically increase transmitter power based on the signal connection, up to 2000mw. They have receivers with diversity antennae, allowing for the antennae to be placed at a different orientations to handle relative positional changes between the model and the Tx avoiding null spots. Another cool feature is telemetry allowing for all sorts of data to be sent back the transmitter for display. The antennae are not large (easily fit inside a cylinder) and the receivers can be standard size or as small as a quarter, depending on how many physical outputs you need to use. This equipment is usually used in model aircraft for flight beyond visual range with the pilot using live video to fly the aircraft, commonly referred to as FPV (first person view). Aircraft using this setup can fly miles away and the pilot can still maintain rc control. It would be interesting to see how it would work under water. Also you can use any transmitter with it as it piggybacks on any radio with a trainer port or ppm out. Unless you all already know about this in which I've wasted everyone's time and sorry lol!
    Last edited by billyd; 02-11-2024, 05:58 PM.

    Comment

    • QuarterMaster
      Rear Admiral
      • Sep 2015
      • 1206

      #17
      Thanks for speaking out!

      The short answer is that it's been already looked at.

      We actually do have a member playing with it. But the general consensus is TBS Crossfire not worth it, price or power as a new purchase.

      1-The Tandem units we employ now are don't need additional hardware. Most people are quite satisfied without the care and feeding of an extra mouth.

      2-We don't "fly" miles away, no need to push envelopes. we can run happily @ 500mw 90% of the time.

      3-While additional power might be great, 99% of use of an RC Sub is LOS, usually within 10m of ones location. Anything further is a blob under water, and periscopes are difficult to track, much less to spot beyond 100m. I know as that's my common distance to run at to avoid surface a$$clowns, maybe 5% of users have an environment to dive deeper than 1m.

      4-Forget POV, not worth it. Back to the common, not clear environment. People have done FPV through a scope, great if you enjoy bouncing video.

      The bottom line, if Crossfire was worth it to exclusively run submarines, it'd be the thing now.

      Don't get me wrong, I'm a tech guy, and love pushing envelopes, but as an Engineer, requirements are are what's useful to me, and there is no specific requirement for ownership of Crossfire. So I wouldn't recommend it to 80-90% here. Maybe if you want to dive beyond 1-2meters, but why? To say you did? THAT is a personal choice and not a requirement for this pastime. Then I do encourage the user to review their needs for the additional expenditure.

      Of course, if you do have it already as a drone pilot or other endeavor, rock on dude!

      Again, thanks for the discussion, and stepping forward!!
      Last edited by QuarterMaster; 02-12-2024, 11:21 AM.
      v/r "Sub" Ed

      Silent Service "Cold War" Veteran (The good years!)
      NEVER underestimate the power of a Sailor who served aboard a submarine.
      USS ULYSSES S GRANT-USS SHARK-USS NAUTILUS-USS KEY WEST-USS BLUEBACK-USS PATRICK HENRY-K432-U25-SSRN SEAVIEW-PROTEUS-NAUTILUS

      Comment

      • billyd
        Lieutenant, Junior Grade
        • Feb 2024
        • 27

        #18
        Originally posted by QuarterMaster
        Thanks for speaking out!

        The short answer is that it's been already looked at.

        We actually do have a member playing with it. But the general consensus is TBS Crossfire not worth it, price or power as a new purchase.

        1-The Tandem units we employ now are don't need additional hardware. Most people are quite satisfied without the care and feeding of an extra mouth.

        2-We don't "fly" miles away, no need to push envelopes. we can run happily @ 500mw 90% of the time.

        3-While additional power might be great, 99% of use of an RC Sub is LOS, usually within 10m of ones location. Anything further is a blob under water, and periscopes are difficult to track, much less to spot beyond 100m. I know as that's my common distance to run at to avoid surface a$$clowns, maybe 5% of users have an environment to dive deeper than 1m.

        4-Forget POV, not worth it. Back to the common, not clear environment. People have done FPV through a scope, great if you enjoy bouncing video.

        The bottom line, if Crossfire was worth it to exclusively run submarines, it'd be the thing now.

        Don't get me wrong, I'm a tech guy, and love pushing envelopes, but as an Engineer, requirements are are what's useful to me, and there is no specific requirement for ownership of Crossfire. So I wouldn't recommend it to 80-90% here. Maybe if you want to dive beyond 1-2meters, but why? To say you did? THAT is a personal choice and not a requirement for this pastime. Then I do encourage the user to review their needs for the additional expenditure.

        Of course, if you do have it already as a drone pilot or other endeavor, rock on dude!

        Again, thanks for the discussion, and stepping forward!!
        Thanks for the response. After writing it all I figured it had been looked at but I left it up just to see what the general consensus is. I do have a crossfire, along with a lot of other rc stuff. I actually built a submarine (Krick Type V11) about 14 years ago. It worked well for awhile but then the water tight compartment ceased being water tight. I looked at trying to fix it but decided maybe someday to get a cylinder for it. It's now mounted on a wall (still functional I believe). That used an old 72mhz radio, and would cut out at about 4 feet deep or so. I just ordered stl's from Bob for the nuclear uss nautilus as I do a lot of 3d printing and have a very large printer (500mm^3) so I thought it would be a fun project for the next several months at least (I build slowly), and was thinking about what rc system to use and found this thread.

        Comment

        • QuarterMaster
          Rear Admiral
          • Sep 2015
          • 1206

          #19
          Originally posted by billyd

          Thanks for the response. After writing it all I figured it had been looked at but I left it up just to see what the general consensus is. I do have a crossfire, along with a lot of other rc stuff. I actually built a submarine (Krick Type V11) about 14 years ago. It worked well for awhile but then the water tight compartment ceased being water tight. I looked at trying to fix it but decided maybe someday to get a cylinder for it. It's now mounted on a wall (still functional I believe). That used an old 72mhz radio, and would cut out at about 4 feet deep or so. I just ordered stl's from Bob for the nuclear uss nautilus as I do a lot of 3d printing and have a very large printer (500mm^3) so I thought it would be a fun project for the next several months at least (I build slowly), and was thinking about what rc system to use and found this thread.
          Awesome!

          Start a new thread under the sub-form "Builders Thread" called "Billy's TYPE VII Krick" or some $#*! and let's start a refit log! No worries about putting it out there, NO one is judgemental (well except maybe HWMNBN, but that's only tough love, the man would give you the shirt off his back to see you succeed).

          Start with some photos as she is.

          Everyone is here to help, and really, just like the US Submarine Service "there is no such thing as a dumb question".

          BTW, I refitted a KRICK U25, now using LiPO, Brushless Motors, new shafts, clear lid, and above all, 900Mhz!!.

          Before...


          Click image for larger version

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          After...

          Click image for larger version

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          .Here's a video snippet of her by Bob himself at a previous run we did together. It starts at the Krick, but be sure to watch the whole thing.

          More Seaview progress, an RC boat battle and more - Update from the Nautilus Drydocks - 12-16-23
          Attached Files
          v/r "Sub" Ed

          Silent Service "Cold War" Veteran (The good years!)
          NEVER underestimate the power of a Sailor who served aboard a submarine.
          USS ULYSSES S GRANT-USS SHARK-USS NAUTILUS-USS KEY WEST-USS BLUEBACK-USS PATRICK HENRY-K432-U25-SSRN SEAVIEW-PROTEUS-NAUTILUS

          Comment

          • billyd
            Lieutenant, Junior Grade
            • Feb 2024
            • 27

            #20
            Originally posted by QuarterMaster

            Awesome!

            Start a new thread under the sub-form "Builders Thread" called "Billy's TYPE VII Krick" or some $#*! and let's start a refit log! No worries about putting it out there, NO one is judgemental (well except maybe HWMNBN, but that's only tough love, the man would give you the shirt off his back to see you succeed).

            Start with some photos as she is.

            Everyone is here to help, and really, just like the US Submarine Service "there is no such thing as a dumb question".

            BTW, I refitted a KRICK U25, now using LiPO, Brushless Motors, new shafts, clear lid, and above all, 900Mhz!!.

            Before...


            Click image for larger version

Name:	IMG_20190910_180453.jpg
Views:	125
Size:	67.7 KB
ID:	178225

            After...

            Click image for larger version

Name:	IMG_20231021_104724_317.jpg
Views:	99
Size:	80.1 KB
ID:	178227

            .Here's a video snippet of her by Bob himself at a previous run we did together. It starts at the Krick, but be sure to watch the whole thing.

            More Seaview progress, an RC boat battle and more - Update from the Nautilus Drydocks - 12-16-23
            Nice! I will take some pics and post it over there, but I am going to work on the USS Nautilus first. One project at a time. The biggest problem with the Krick model will be getting the wtc out of the boat. I glued the heck out of it into the hull!

            Comment

            • QuarterMaster
              Rear Admiral
              • Sep 2015
              • 1206

              #21
              Originally posted by billyd

              Nice! I will take some pics and post it over there, but I am going to work on the USS Nautilus first. One project at a time. The biggest problem with the Krick model will be getting the wtc out of the boat. I glued the heck out of it into the hull!
              Oooooooo...571...sweeeeet!
              v/r "Sub" Ed

              Silent Service "Cold War" Veteran (The good years!)
              NEVER underestimate the power of a Sailor who served aboard a submarine.
              USS ULYSSES S GRANT-USS SHARK-USS NAUTILUS-USS KEY WEST-USS BLUEBACK-USS PATRICK HENRY-K432-U25-SSRN SEAVIEW-PROTEUS-NAUTILUS

              Comment

              • Thorbrandr
                Lieutenant Commander
                • Mar 2022
                • 133

                #22
                I am ruining a TBS Crossfire Diversity with two dipoles on SMA connectors n my 212. I have space in the upper half of the WTC to run them crossed at about 30 degrees and at an angle up toward the bow. I had to work around the remote control, and the lower half of the WTC is taken up by a rather large battery. I figured that most of my running the side of the boat is presented to the radio, so this geometry seemed ok. it worked on the green water first run. I would need to do some moving of components and desoldering to get a more vertical orientation on the antennas.

                I did lose telemetry below 4 feet or so. I was able to run the sub out at 50-60' submerged. I did have a few geometries where responsiveness dropped. Seeing this thread I will have to go back and test that some.

                Sometimes if the connection gets spotty, try rotating your radio about the line between you and the sub to cut polarization mismatch losses. It can help. It does not help if you are in the receiving antenna null.

                Note, as an RF systems engineer (not quite the same as an RF engineer or an antenna engineer) this thread makes sense.

                Comment

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