Welcome to your 900Mhz Dipole Antenna!

[RCSubGuy]

Yep, what Andy said. Salt kills signal.

[Subculture]

If you have salty or brackish water you can expect your radio signal to be severely compromised no matter what frequency you operate at.

[Occupant]

Curious about workable depths with 900 mhz with the dipoles, fairly new here doing test runs on a drive system . For my test only the drive motor esc are connected and i'm running to monitor speed and current. with a little speed i start seeing it dive due to a little pitch on the dive planes and after it gets about a foot under the water it loses communication and just runs around the bottom of the pool - yeah i need to set a failsafe just been focused on other things. My question is how deep can you typically get ? One theory is it the salt content in the pool (running a salt cell for chlorination). as a sanity check going to fill a 100 gallon farm tub with city water, sink it to the bottom and see if i get signal to determine if salt is the culprit. Anyone have experience in this type issue?

[He Who Shall Not Be Named]

Blue pill on the loose.

[redboat219]

...............

[Thorbrandr]

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.

[QuarterMaster]

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!

[billyd]

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...



After...



.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!

[QuarterMaster]

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...



After...



.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

[billyd]

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.

[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!!

[billyd]

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!

[rwtdiver]

For me, its 75 Mhz, if I can find them, and if not, 2.4 all the way. Just do not need all that tech stuff to run submarines. But, if that is your cup of tea, coffee, coke, or what ever. Go for it!

Rob
"Firemen can stand the heat."

[QuarterMaster]

That is exactly what I was contemplating

GFL making it reach! Boy I wanna see that!

Now REREAD Bobs analysis!

But feel free to make extra work for yourself with an additional point of failure for 5-10% increase!

FWIW. no worries on anymore comments from me, I'm done here. Moving away from this subject at A/A Flank. Ping away boys!!

[Nathan]

How about disguising the antennae as one of the mast?

That is exactly what I was contemplating