New to subs - A few general questions

[anonymous]

Hello everyone, I am new to subs but i have been into RC in general since i was 7. I have had every rc thing imaginable(less a sub) including many scatchbuilt things. I am also fairly versed in digital and analog electronics, having made severals robots.


First question,

I have done some tests recently and have found that my sub can blow ballast in slightly under 7 seconds, and it can dive in about 10 seconds. The question is, is this about right or should it go faster? The tanks are a total of about 1 Gallon and im using 60-100PSI through 1/8" fittings.


Second,

I cant seen to find pictures of the tail of an AKULA out of water and Ive decided i would like to do an X tail rather that a + tail. Question is, is this correct? did the AKULA have an X tail?


Third,

What is an average depth? 10 feet? more? I am going to try to equip it with some type of sonar or a 2 axis 360" camera so i fiqured i should be able to navigate at a depth. Also how many PSI would the hull have to take at that depth?


Lastly,

Is there any real reason i cant use an Aircraft radio rather than a ground radio? Is it just some rule a guy in an office made up or is there and issue with how it works? I have used aircraft radios in robots on the ground and have had no problems so im just not sure about that.



Edited By MRunhart on 1160872291

[chips]

I'll answer your last question

I'll answer your last question about aircraft/surface radio frequencies. Go check with the Canadian equivilant of the US Federal Communications Commission and find out what the rules are for your country - and follow them. Here in the US, the FCC has substantial penalties for knowingly operating on the wrong frequency. Some guys in a governmental office didn't make the rule up on their own, but they considered several things like accidents, increasing the number of radio hobbyists, and "pursuit of life, liberty, and happiness". There were several accidents where airplanes were "shot out" of the air on shared frequencies (27 MHz), by someone running a surface model. In most cases the surface operator and the aircraft pilot did not know the other guy was in the area. That's one reason the AMA has a flying field separation requirement. The frequency separation plan is there to protect all of us and allow us to continue to enjoy the hobby.

The government grants us the PRIVELEDGE of operating rc models. That priveledge can be revoked at any time.

Short history lesson on US radio frequencies, probably similar for Canada.
1973 we had 5 frequencies on 27 MHz, all shared by airplanes, cars and boats. We also had 7 frequencies on the 72-75 MHz band, four were aircraft only and 3 were shared.
1984 we got 6 frequencies on 27 MHz. The 72-75 MHz band had 18 frequencies, 15 were aircraft only and 3 were shared. We also got 10 frequencies on 75 MHz for surface models only.
1988 we had 6 frequencies on 27 MHz; 22 frequencies on 72 MHz for aircraft only, none shared; and 15 frequencies on 75 MHz for surface models.
Finally in 1991 we have 6 frequencies on 27 MHz all shared; 50 aircraft only frequencies on 72 MHz; and 30 surface model frequencies on 75 MHz.

At the SubRegatta, the maximum depth of the Carmel reflecting pool is about 3 feet, so average depth is about 18 inches. Most guys are happy to cruise at periscope depth without porpoising. Some of the WTC's are warrented for 1 atmosphere of pressure, about 33 feet of depth. ROghly 0.5 psi per foot of depth, 33 feet = 15 psi; 10 feet = 5 psi.



Edited By chips on 1160883167

[silent runner]

Welcome aboard!
To answer some questions;

Welcome aboard!
To answer some questions; Akula Class SSN's do not have 'x' tails. For excellent references, consult Wayne Frey's Book,
Russian Subamrines, Guardians of the Motherland,
available through Amazon Books.
As far as depth, radio waves penetrate to 8-10 feet in depth, and any deeper, you can't see it anyway.
Diving speed is based on how accurate to scale you wish to be. Since you have not indicated what sub you are running, hard to judge, but my 'nuke boat' dive rather slow, typical to scale.

The FCC REQUIRES that all r/c aircraft are flown on 72Mhz radios and all surface use,i.e; cars, boats, ROBOTS are controlled with 75Mhz radios. So, get yourself a 75Mhz radio to operate your boats/robots on as they are readily available, and you won't be interfering with the fly boys.

[raalst]

Hi,

just a detail ]



Edited

[color=#000000]Hi,

just a detail ]



Edited By raalst on 1160903891

[anonymous]

Has anyone ever tried using

Has anyone ever tried using a 75 Mhz crystal in a 72 Mhz radio? Is it possible that it could work? If not then I'll just use my 2 channel surface radio with an expander.


Also has anyone found a way to modify a cameras transmission frequency low enough to penetrate pool water well? Could you somehow modify it to use a hydrophone for transmission?


As for diving i just wanted to make a submarine to have fun with, not particullarily to be scale. I just want to know how it would compare with other subs, like if I'd be left behind.

[himszy]

Someone at my school had

Someone at my school had crystals in the 'wrong' TX and RX and it worked.....to what degree I don't know......

I would imagine that you can't lower the camera frequency as otherwise the reduced bandwidth won't carry enough data to form a picture.

I'm 99% sure you certainly can't use an acoustic system....

Michael

[chips]

Has anyone ever tried using

Has anyone ever tried using a 75 Mhz crystal in a 72 Mhz radio? Is it possible that it could work? If not then I'll just use my 2 channel surface radio with an expander.

It is possible that it would work, but not real well. All of the major radio makers (Futaba, JR, Hitech, Airtronics, et al) mention on their websites and in their radio manuals that you need to have the radio retuned at a factory authorized service center, when you change from 72 to 75 MHz (as well as changing from 75 to 72 MHz).

The best analogy I can come up with is driving from you home to a regatta 200 miles away. You leave home listening to your favorite radio station in your car. Around 60-75 muiles from home, your favorite radio station starts fading out and you finally lose the station.

[chuck chesney]

The realities of the hobby

The realities of the hobby are that you need a certain amount of basic equipment to run model subs, or even surface ships. A real 75mhz surface radio is the most basic of all. Radios are cheap, in a hobby that is'nt. Plan on getting a radio, probably four or five channel, minimum. Aircraft frequency radios are for planes, not submarines, because you don't know where those radio waves are going, or what they're doing to sombody else.

[anonymous]

There's a lake within 2

There's a lake within 2 miles of my RC aircraft field. A lot us fly very expensive RC jet aircraft. If one of those goes out of control it could kill someone. If you are caught your going to jail. It's simple. Get a 75 MHz radio. They are a lot cheaper than the lost of life or and expensive RC aircraft.

Steve