Advice On Getting A Set Of Radios

[EastCoastSunrise]

Ill open with this, my knowledge comes from scanners and poking around the forums here alongside some YouTube videos and internet articles. Anyway, I recently have been come involved with the USS Salem based out of Quincy MA. Onboard communications are poor, often no one knows who's on the ship and even if we know your on the ship we rarely know where. The only way to contact people is to text them and hope they receive it trough all the metal (unlikely) or go over the "1MC" which is a ship wide PA that is only one way. There is a ship service telephone system that does not work as the exchange that switched the system is not working right. Either way I mentioned to some other volunteers and a few people in charge that I think we should get some two way radios for shipboard communications. The place of use is well a ship, its made of steel, lots, lots of steel. So RF transmission from cell phones isnt an option. So I am looking for some advice / options for handhelds we can use onboard. I have not had a change to take my FRS radios on board to check their range but I am doubtful they will have enough power. Even if they did work they are not rugged enough nor do they have enough battery to last all day. Based on what I know, I think digital radios would be best but I will leave those suggestions up to the experts here. There is also the question of whether or not we should have a repeater? Again feedback is welcome here. Cost is a factor, but I just want to hear what people recommend so I have a rough idea and can go back and pitch it to those up the chain from me.

EastCoastSunrise

 

[clbsquared]

This really isn't the place to be asking these types of questions. You should clear all of this with your command staff. Personal radios used on US Navy ships could cause unwanted interference with onboard equipment. Consult with your ships command and / or communications group.

 

[KevinC]

This really isn't the place to be asking these types of questions. You should clear all of this with your command staff. Personal radios used on US Navy ships could cause unwanted interference with onboard equipment. Consult with your ships command and / or communications group.

I think it’s a floating museum, so probably privately owned.

 

[EastCoastSunrise]

I think it’s a floating museum, so probably privately owned.

@clbsquared

This is the case, sorry for not making it much clearer earlier, my bad. It is a privately owned museum ship. At this time most of the stuff that would be interfered with is offline, and likely will remain that way. (The FAA doesn’t like when you light up a fairly powerful air search radar 5 miles from Logan airport) other gear that could be interfered with will be re enabled in such a way as to not cause interference. Before I started there was an attempt made at using FRS/GMRS/MURS radios but given they were inexpensive units performance was poor. I’ve gotten the okay to investigate options for later evaluation. Also @clbsquared thank you for your concern with interference, and doing this right. Without me telling you, you’d have not idea.

 

[JethrowJohnson]

I think it’s a floating museum, so probably privately owned.

I'm not sure, would they be allowed to use HAM if they got a HAM license or is amateur HAM only for a hobby? I would suggest GMRS but he said that wasn't working well.

 

[RFI-EMI-GUY]

The proper solution would be a commercial FCC part 90 license. Not knowing the specifics, I will share some experience. I designed a radio system configuration for four medium sized cruise ships. Meeting the coverage was quite challenging. It included a repeater in the engine room, hundreds of feet of radix and heliax cable , power splitters, low profile antennas , duplexes, a voting comparator and satellite receiver. It worked quite well. Today you might be able to accomplish something similar in performance with MotoTrbo, IPSC and two or more repeaters. In short, a solution may require some investment in engineering and equipment.

 

[EastCoastSunrise]

The proper solution would be a commercial FCC part 90 license. Not knowing the specifics, I will share some experience. I designed a radio system configuration for four medium sized cruise ships. Meeting the coverage was quite challenging. It included a repeater in the engine room, hundreds of feet of radix and heliax cable , power splitters, low profile antennas , duplexes, a voting comparator and satellite receiver. It worked quite well. Today you might be able to accomplish something similar in performance with MotoTrbo, IPSC and two or more repeaters. In short, a solution may require some investment in engineering and equipment.

I was expecting to need some kind of license. Again I didn’t do a good job making this clear in my original message, but this was more so I could learn about what others believe we need to get, that way I can pitch to the board a rough cost/what’s needed. Which hopefully may help us to avoid being totally swindled by the Motorola sales person, who we will need to talk to anyway.

 

[littona]

Part 90 license, with a repeater using "leaky coax" as an antenna. One such brand name is RADIAFLEX. From a spec sheet: Slots in the copper outer conductor allow a controlled portion of the internal RF energy to be radiated into the surrounding environment. Conversely, a signal transmitted near the cable will couple into the slots and be carried along the cable length.

Such systems are used underground in mines, in tunnels, and other areas where typically antennas just don't work. This is something a professional radio shop would install and it wouldn't be cheap. Tessco sells 1/2" RADIAFLEX for $3.55/foot. You'd basically run this cable as an antenna, everywhere you need comms.

 

[Mike_G_D]

See if you can get a pair of Motorola DTR type freq. hopping 900MHz radios and try those before jumping into a costlier solutions like adding a repeater or leaky coax install and getting licensed, etc. The DTR's seem to work very well onboard cruise ships based on reports I have read and are license free. Try and find a dealer who will allow you to test them out first or at least take them back if they don't work for you. Worth a shot and if they work might save you money over a larger Part 90 system, etc.

-Mike

 

[RFI-EMI-GUY]

I was expecting to need some kind of license. Again I didn’t do a good job making this clear in my original message, but this was more so I could learn about what others believe we need to get, that way I can pitch to the board a rough cost/what’s needed. Which hopefully may help us to avoid being totally swindled by the Motorola sales person, who we will need to talk to anyway.

A lot of it is based upon expectations of performance. Is the system simply for convenience of those conducting tours? Is there a life safety aspect such as evacuation ? Are bulkhead doors ever going to be closed, say a fire or flood occurs? These all affect the design. Radiax is one solution. There are different types depending on antenna polarization, cable orientation versus polarization, frequency band of operation, insertion loss versus coupling loss.

If this is simply a convenience issue with no regard to life safety or any standards of such, different radio technologies like DTR FHSS could be tested to see if they meet day to day requirements.

Has WIFI been installed?
There is this license free option, however, it would require several, perhaps many WIFI AP's and CAT5 to be installed throughout the ship. Labor potentially equivalent to the Radiax effort.

IP100H License-free IP radio for wireless network (WLAN) - Features - Icom America

www.icomamerica.com

Regarding standards, wiring on the ship may need to be plenum rated for fire protection if such standards still apply to a museum ship.

 

[mmckenna]

I'm not sure, would they be allowed to use HAM if they got a HAM license or is amateur HAM only for a hobby? I would suggest GMRS but he said that wasn't working well.

No.
Amateur radio has very specific rules about this.
§ 97.113 Prohibited transmissions.
(a) No amateur station shall transmit:
...
(3) Communications in which the station licensee or control operator has a pecuniary interest, including communications on behalf of an employer, with the following exceptions:
(exceptions removed as they don't apply)

Even if it was permitted, each and every person transmitting with a radio would need to have their license.

GMRS can be used, but again, it requires each family to have their own license.

Ham/GMRS are not the right radio services for this.


As others said, I'd probably try a pair of the Motorola DTR 900MHz radios. People that have used those on cruise ships say they work pretty well. Would be the easy solution, and won't require filing for a license from the FCC.

If those don't do the trick, you're going to have some challenges.
The "leaky coax" systems are a good option, but they are expensive. If this is volunteers/museum type stuff, you probably do not have the budget for that.

The 1MC would be your best option, and then get the phone system working. Check on some of the Navy Veteran facebook pages and see if you can find some retired interior communications electricians (IC Rating) to help you get it back in working order. Shouldn't be a huge issue unless someone removed major parts of it. It would add to the museum part of what you are doing.

 

[MUTNAV]

I was REALLY trying to not make a comment about this.... but the ship is an afloat museum ship, right?

To not know how many people are onboard seems to be a big issue to me.


As far as an actual helpful comment though, there should be a number of sound powered circuits aboard, there may be a possibility of using one of them to either act as the leaky coax, or use the circuit as a conduit for some other RF... i.e. unplug all of the sound powered handsets (if any), and try an FRS walkie talkies near one of the plug in boxes, then try it with a small antenna cut to an appropriate length plugged into some of the plug boxes, and see if it helps as a passive repeater (or whatever happens)..., have fun, experiment

or you could use them as sound powered circuits (interior communications I think was a career field in the navy at one point, which means lots of work to do).

and PLEASE get a sign in / out sheet for the boat,, think of a small fire, the fire department arrives and wants to know how many people are on board, and if everyone is off....

or what the funny smell is coming from the bilge and where has bob been for the past six months

, or someones wife is calling about their spouse that never returned from the volunteer work two days ago.

If you guys don't get a handle on this, then after the first incident, the local authorities will force someone to come up with an operations - safety plan.


Thanks
Joel

 

[RFI-EMI-GUY]

general layout here.

reunion2015salem1

www.usshelena.org

 

[MUTNAV]

No.
Amateur radio has very specific rules about this.
§ 97.113 Prohibited transmissions.
(a) No amateur station shall transmit:
...
(3) Communications in which the station licensee or control operator has a pecuniary interest, including communications on behalf of an employer, with the following exceptions:
(exceptions removed as they don't apply)

Even if it was permitted, each and every person transmitting with a radio would need to have their license.

GMRS can be used, but again, it requires each family to have their own license.

Ham/GMRS are not the right radio services for this.


As others said, I'd probably try a pair of the Motorola DTR 900MHz radios. People that have used those on cruise ships say they work pretty well. Would be the easy solution, and won't require filing for a license from the FCC.

If those don't do the trick, you're going to have some challenges.
The "leaky coax" systems are a good option, but they are expensive. If this is volunteers/museum type stuff, you probably do not have the budget for that.

The 1MC would be your best option, and then get the phone system working. Check on some of the Navy Veteran facebook pages and see if you can find some retired interior communications electricians (IC Rating) to help you get it back in working order. Shouldn't be a huge issue unless someone removed major parts of it. It would add to the museum part of what you are doing.

You posted while I was still writing my post....

i agree, the interior communications thing I think would add to the museum, just like showing off the voice tubes from the bridge to the helm (assuming they had them).

Thanks
Joel

 

[RFI-EMI-GUY]

I was REALLY trying to not make a comment about this.... but the ship is an afloat museum ship, right?
To not know how many people are onboard seems to be a big issue to me.
(snip)
and PLEASE get a sign in / out sheet for the boat,, think of a small fire, the fire department arrives and wants to know how many people are on board, and if everyone is off....
or what the funny smell is coming from the bilge and where has bob been for the past six months

, or someones wife is calling about their spouse that never returned from the volunteer work two days ago.

If you guys don't get a handle on this, then after the first incident, the local authorities will force someone to come up with an operations - safety plan.


Thanks
Joel

I spent a couple weeks surveying some old cruise ships that had been sectioned and lengthened and they were a maze of compartments and tanks and mechanical gear. In this case coverage needed to be ensured everywhere that a person could go. We had coverage from the Bow thruster room to the rear propeller shaft and everywhere between and above. Most of it via strategic antennas and signal margin adequate to penetrate adjacent compartments.

Yeah "Bob" could easily be little Bobby who wandered off to get a better look. So having cameras and motion sensors (recorded) beyond the restricted zones would be a good idea when the headcount comes up short.

 

[RFI-EMI-GUY]

Regarding the phone exchange (PBX) . There are some older small office, home office type PBX's that can support POTS extensions in an intercom arrangement. If your phone system on board roughly complies with POTS phones usually DTMF and ringing voltage you can drop one of these in on a wall and wire up a dozen or more extensions. You will need at least on fancy advanced phone set to provision it. The existing twisted pairs could also be utilized with modern phone sets. From there you can add cordless phones for convenience in certain locations. If the phones are rotary you can convert rotary to DTMF at the phone set. You can also do auto ringdown which may be a preferred method. The website for SANDMAN is a good start. Telecom Troubleshooting Equipment, Custom Handsets, Custom Cable Assemblies and More...

 

[mmckenna]

Regarding the phone exchange (PBX) . There are some older small office, home office type PBX's that can support POTS extensions in an intercom arrangement. If your phone system on board roughly complies with POTS phones usually DTMF and ringing voltage you can drop one of these in on a wall and wire up a dozen or more extensions. You will need at least on fancy advanced phone set to provision it. From there you can add cordless phones for convenience in certain locations. If the phones are rotary you can convert rotary to DTMF at the phone set. You can also do auto ringdown which may be a preferred method. The website for SANDMAN is a good start. Telecom Troubleshooting Equipment, Custom Handsets, Custom Cable Assemblies and More...

We had both sound powered phones as well as a small PBX on the ship I was on.

A basic analog PBX would be an option. Nothing fancy.
If the ship already had them installed, and especially suitable twisted pair wiring, it would be a good solution.
The sound powered phones would be easy, if they were not removed.
WiFi would be a great option. Good idea...
Most IT guys could put in a basic WiFi network pretty easily. Some could even set up a small IP phone system.

900MHz DTR's would be my first choice. I'm sure access to spaces on the ship are somewhat controlled.

 

[DeoVindice]

Regarding the phone exchange (PBX) . There are some older small office, home office type PBX's that can support POTS extensions in an intercom arrangement. If your phone system on board roughly complies with POTS phones usually DTMF and ringing voltage you can drop one of these in on a wall and wire up a dozen or more extensions. You will need at least on fancy advanced phone set to provision it. The existing twisted pairs could also be utilized with modern phone sets. From there you can add cordless phones for convenience in certain locations. If the phones are rotary you can convert rotary to DTMF at the phone set. You can also do auto ringdown which may be a preferred method. The website for SANDMAN is a good start. Telecom Troubleshooting Equipment, Custom Handsets, Custom Cable Assemblies and More...

Femco paging mine phones on a party line circuit might work fine too.

 

[RFI-EMI-GUY]

Cheap used systems. Buy enough "ports" to support the number of "POTS extensions" plus one feature phone for configuring the system. Calls will be made in the intercom mode or as ring down. You can reserve a port for outbound calling on a leased POTS line or ATA device, IP or Cellular.

Partner Systems and Cards Archives - Wholesale Telecom Inc.

wholesaletele.com

 

[alcahuete]

There is a lot more metal in the military ships, but I have had full ship coverage on the largest cruise ships in the world with DTR radios. They are fantastic, and license free.

Never tried them on a military ship, but it might be worth getting a pair to test.