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SPetty
01-11-2005, 11:07 AM
I need wireless two-way always-on communication between at least two and maybe three buildings.

I tried the little cheapo walkie talkie things. They didn't work well and they were battery operated so they were never on.

There probably isn't "line-of-sight", because they are inside buildings behind walls, not on the front porch of the buildings.

I need the capability for one to signal the other to pick up and communicate. I don't need any "monitoring" capability - leaving it on in listening mode.

Anybody had any experience with anything like this?

Sid_Vicious
01-11-2005, 11:22 AM
How about the FRS radios? I'd imagine that you should get good results, especially if you are talking about buildings outside the city, such an at the Ponderosa...sid

Barbara
01-11-2005, 11:22 AM
SPetty,

Radio Shack has two-way intercom systems. We have a setup between the kitchen and Pete's workshop so I don't have to go outside when I need to talk to him. And this system plugs into a wall outlet so you can have it on all the time or at least when there's power to the outlet.

HTH,

Barbara

EDIT:

They also have a 3-way:

3-way intercom system (http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&category%5Fname=CT LG%5F008%5F005%5F002%5F000&product%5Fid=43%2D3105)

SpiderMan
01-11-2005, 12:28 PM
Knowing your setup, I'd recommend FRS radios. They operate around 460 MHz, so the communication is line-of-sight and short range (a mile or two). In your environment, you're unlikely to experience much interference because you don't have many people living within the radio's range.

I don't know the details of your less-than satisfactory experience with walkie-talkies, but do it this way and you should be OK:

Select radios that come with rechargeable batteries and a drop-in desk charger. This addresses your issue of battery usage. You can leave the radios "on" and in the charging cradles in each building.

All of these radios will have a "call" button that transmits a loud and obnoxious ring tone to the receiving unit.

Buy radios that have CTCSS (subcodes) to reduce the possibility of false triggering by other transmitters, such as the occasional user passing by on the main road. Note that this feature is only a fancy squelch function on the receive end, it does not encrypt or otherwise provide privacy of communications. In other words, don't discuss your sex life on the air /ccboard/images/graemlins/grin.gif

If you watch the sales, you can get radios as I've described for about $25 a pair at Fry's.

Using FRS radios instead of standard intercoms will have the additional advantage of portability - Leroy can clip one to his shirt when he takes the tractor to the north forty, and you'll still be in touch.

SpiderMan

highsea
01-11-2005, 03:13 PM
I would go with one of the Motorola business portables. No question in my mind whatsoever. They are WAY better than FRS systems, which are absolute junk, imo. (sorry, Spidey, but I've used both. /ccboard/images/graemlins/smirk.gif)

The CP200 rocks, 5 watts VHF, but it's a little pricey. The XV2100 and XV2600's are nice also, but lower power. I would NOT go less than 2 watts, if I wanted to communicate between buildings or floors. These things are always rated in ideal conditions, so MORE POWER is always better!

You can look for these on ebay and find decent deals. Also, you can find used spirit's in 5W VHF at very reasonable prices. They are multi-channel and reprogrammable. You have to go to a radio shop to reprogram them, but it is cheap to do. If you buy used ones, I suggest you buy them in sets, so you have matching frequencies.

You have two choices, VHF or UHF. VHF is better for outdoors and wooden structures, and UHF is better for indoors and concrete and steel structures. The better UHF portables are usually 4 watts.

You can get lower power ones, but range will suffer. Almost all of the portables have a "beep" button to get someones attention. You can also get base stations and mobile versions that can go in trucks, tractors, etc., and work on the same frequencies, but have more power, like 45 watts.

FRS radios are only 500mw. Commercial portables range from 1 to 5 watts. They require an FCC license, but I think its's free, at least it is for marine VHF's. It's just a form to send in. To be honest, if I bought a set on ebay, I wouldn't worry about the license, but that's just me...

All of these radios have charging bases, and will last all day on a charge. I have used them for years in warehouses, multi-story buildings, campuses, etc. They are great little radios.
_______________________

SpiderMan
01-11-2005, 03:59 PM
<blockquote><font class="small">Quote highsea:</font><hr> I would go with one of the Motorola business portables. No question in my mind whatsoever. They are WAY better than FRS systems, which are absolute junk, imo. (sorry, Spidey, but I've used both. /ccboard/images/graemlins/smirk.gif)
<hr /></blockquote>

If you saw her setup you might rethink that. Max distance between buildings (wooden structures) is about 400 feet.

I agree that there are some junk FRS radios out there, but good ones abound and are dirt cheap. If you're hung up on Motorola, they also sell FRS radios, and they work really well.

Business band is a bad idea for this application, as it does require a license, which is not free, and they do enforce compliance in Texas. Over the past year I read of a Dallas case where they made an "example" of some guys that were using rented business-band radios unlicensed for convention facilities coordination. I think the fines were well into the thousands.

The other radios you mentioned operate in the 156-MHz marine band and also require licensing, but the main problem is that they are highly illegal (big potential fines) for land-land use. Their range is great enough that if you live within 10 or 15 miles of a lake or navigable river you will probably get caught. Plus, why would you intentionally use a radio capable of interfering with other communications over a radius of many miles, when your main application is 400 feet?

For Spetty's application, she should be considering legal radios operating at UHF frequencies. This limits coverage to a few square miles, which is a good thing.

My FRS radios (I probably own 10) provide capability on par with what I achieve on the 70-cm ham band, operating simplex with a high-quality Icom handheld, but at a far lower cost and without licensing requirements.

FRS band crowding gets to be an issue at ski resorts and in the suburbs (because of all the baby monitors and kid's toys), but that doesn't apply to Spetty's environment.

SpiderMan

highsea
01-11-2005, 04:45 PM
I would still go with GMRS. Even thought the license costs 80 bucks, it not resricted to businesses, and you don't have the 500mw limit. I have used the ICOM FRS radios, and couldn't even get a clear communication between the engine room and bridge on a 100 foot boat. I switched to VHF portables on low power (1W) for inter-ship communication.

I wasn't recommending marine VHF for use on land. I was only pointing out that the license had no fee. I have since checked on GMRS, and they do have a fee. /ccboard/images/graemlins/frown.gif

I haven't seen Spetty's place, so FRS may work fine, it sounds like there is no interference. When she said she had tried those "cheap walkie-talkies", I assumed she was referring to FRS. Hell, CB is superior to FRS, we use them around the marina as a private "party line".

SpiderMan
01-12-2005, 07:01 AM
If you couldn't get 100 feet with FRS, there had to be a logical reason. Was this a boat of metal construction, ie was the engine room a Faraday cage? Another possibility is that the engine room was too noisy. Some of the really small FRS radios don't have much audio output, and you might have been cranking up the volume to distortion levels trying to hear. If neither was the case, I'd be tempted to guess you had a defective radio.

GMRS is no different in propagation characteristics than FRS, they even share frequencies. For your license fee, you get to use higher power, repeater operation is permitted, and there are (I believe) 8 additional channels (22 vs 14).

CB is "superior" to all of the other radios we have discussed only if your criteria is maximum range. At 27 MHz, the propagation characteristics support ionospheric reflection of the signals, or "skip". For this same reason, CB is "inferior" to FRS/GMRS for local communications. Who wants to hear signals fading in from five states away, when you're trying to talk from your house to your barn? Also, you can't build a small handheld CB that works well because of the antenna - the most compact effective design will be at least a couple feet long. The four-watt handheld CBs with "rubber duck" antennas actually give poorer house-to-house results than FRS, plus they're still five times the size and eat batteries to boot.

BTW, "skip" capability is a direct function of frequency, higher frequency = less skip. Lower frequencies are also less affected by terrain and obstacles. That's why ham operators use 160 meter wavelengths for worldwide communications, and also why 70 centimeters was chosen for FRS/GMRS. It's really a well-thought-out band plan, for it's intended application.

Next time I'm out to SPetty's I'll take some radios and see what happens.

SpiderMan

Sid_Vicious
01-12-2005, 07:21 AM
I noticed that LeRoy did use a lot of metal banding, at least on the under pinning of the roof. I'd imagine this might be an issue...sid

SPetty
01-12-2005, 09:59 AM
I hadn't paid attention to the word FRS before, so I don't know if the ones we tried were FRS. But you know when you go into the electronics store and they sell these bubble packages with what used to be called walkie talkies? That what these are. They have rechargeable batteries that plug into a charging plug rather than a base station. It's been months since I fooled with them, but I recall that you had to set them both to the same "station". But the squelching mechanism wasn't very good, and the static level when talking/listening was high. Hard to understand, and sometimes it would just start making the static noise so you'd have to go turn down the squelch thing. Rather than fool with it, we just turned them off, thinking we'd turn them on when needed, but we never did. They were a gift, but I do think they were cheap.

What do highsea and Spiderman, or anyone else, think about the intercom system posted by Barbara? Do you know anything about those? I don't think we necessarily need the portability of the hand-held units, although I can see that there could be additional uses for them if we went with that.

Thanks for your help so far! I've learned a lot...

Sid_Vicious
01-12-2005, 11:18 AM
Spetty...My FRS radios also went bonkers with squelch too, and mine never really were used much after that. Spidey seems to have a good opinion though so I wonder if you and I may have gotten bummers when we bought our.

Is Barbara's wireless? If so then I'd probably have to try those since you could always take them back if they did not work over that distance. sid

SpiderMan
01-12-2005, 11:58 AM
Spetty,

I'm not familiar with the intercom systems as mentioned by Barbara. If they are sold as "wireless", they might be true radios or they might be devices which modulate and transmit their signals to one another via your house wiring. They could even be FRS radios in different packaging.

The radios you bought were probably FRS band if they were recently acquired; if four or five years old they were probably situated in the 49-MHz cordless-phone band. The 49-MHz talkies never worked well, they were toys at best. Most FRS radios have 14 channels, does that match up with what you have? If your radios were FRS, it sounds like they did not work up to par or possibly you didn't set the subcodes to keep the squelch quiet.

I can tell you to stay away from the "Conair" or "Columbia" brands of FRS, they are junk. I've had really good luck with FRS radios from Motorola, Alinco, and Midland. Don't own any Cobras, but their reputation is that they make some good and some not-so-good gear.

Next time I'm out your way, let's check out the radio thing. Remind me to bring mine.

SpiderMan

highsea
01-12-2005, 12:28 PM
<blockquote><font class="small">Quote SpiderMan:</font><hr> If you couldn't get 100 feet with FRS, there had to be a logical reason. Was this a boat of metal construction, ie was the engine room a Faraday cage?<hr /></blockquote>
Nope. Fiberglass boat. Though there was a lot of wiring, etc. between decks. The FRS radios (we had a half dozen or so) didn't work worth a crap even from the bow (on deck) to the bridge, a distance of about 30 feet! Lousy SNR, poor squelching, crappy speakers, insufficient volume (if the wind was blowing the wind noise was louder than the radio). They were okay for beeping at each other, that's about it.

In defense of the radios, the bridge was highly electronic, with multiple radars, GPS's. VHF's, Sonar, Computers, etc. And the handheld VHF's did not have to punch through all this, they only had to make it to the ships antennas, which were mounted on the Radar arch.
<blockquote><font class="small">Quote SpiderMan:</font><hr> Another possibility is that the engine room was too noisy. Some of the really small FRS radios don't have much audio output, and you might have been cranking up the volume to distortion levels trying to hear. If neither was the case, I'd be tempted to guess you had a defective radio. <hr /></blockquote>We had ICOM's, and some radio shack type ones. We bought them because we thought they would be good for people to take with them when they went ashore, or on the jet skis, etc. They all ended up in the junk drawer, and we used the VHF's.
<blockquote><font class="small">Quote SpiderMan:</font><hr>GMRS is no different in propagation characteristics than FRS, they even share frequencies. For your license fee, you get to use higher power, repeater operation is permitted, and there are (I believe) 8 additional channels (22 vs 14). <hr /></blockquote>Correct. The advantage GMRS gives you is high power. Most of the GMRS radios are dual band, so they have the FRS frequencies also. I think these radios are generally better quality, so a dual band radio on FRS frequencies may work a lot better than a cheapo "FRS only" radio. In radios, you get what you pay for. You wouldn't need the license (for the FRS freqs), and if FRS didn't work, you could switch to the high power frequencies. Also, since GMRS frequencies are not coordinated, so you would be much less likely to get in trouble using them if you were unlicensed.<blockquote><font class="small">Quote SpiderMan:</font><hr>CB is "superior" to all of the other radios we have discussed only if your criteria is maximum range. At 27 MHz, the propagation characteristics support ionospheric reflection of the signals, or "skip". For this same reason, CB is "inferior" to FRS/GMRS for local communications. Who wants to hear signals fading in from five states away, when you're trying to talk from your house to your barn? Also, you can't build a small handheld CB that works well because of the antenna - the most compact effective design will be at least a couple feet long. The four-watt handheld CBs with "rubber duck" antennas actually give poorer house-to-house results than FRS, plus they're still five times the size and eat batteries to boot. <hr /></blockquote>I don't use portable CB's so I can't say much about them. We do use CB's for close range comm on boats though, and most of the time the call quality is better than VHF. Vessels within the fleet still use CB's to talk to each other, as do a lot of sport fisherman. But they fade fast with range unless you are doing really high power CB and skipping. It's easy enough to squelch out the skip.

I'm probably not a good person to ask about this stuff. I swore off consumer electronics years ago. Everything I use has to be able to withstand severe service, so I automatically go with Mil Spec for everything. On the ocean, our radios are our safety nets. We have to be able rely on them in adverse conditions. Nothing worse than a piece of electronics that only works when the "sun is shining".

Anyway, that's why my first choice in portable (non-marine) radios is the commercial class motorola stuff. I know that it will work when I need it, and it's worth it to me to spring for the license. But I agree it's not for everybody, or there wouldn't be FRS radio in the first place.
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Barbara
01-12-2005, 01:34 PM
<blockquote><font class="small">Quote Sid_Vicious:</font><hr>
Is Barbara's wireless? If so then I'd probably have to try those since you could always take them back if they did not work over that distance. sid <hr /></blockquote>

Yeah Sid, they're wireless. I have one plugged in by the back door with the little antenna raised up, turn it on, and press the bar when I want to speak. It's an intercom system.

The only thing may be that they have a range limit. It doesn't say on the website or in the product description.

Barbara

SpiderMan
01-12-2005, 01:53 PM
<blockquote><font class="small">Quote highsea:</font><hr> <blockquote><font class="small">Quote SpiderMan:</font><hr>GMRS is no different in propagation characteristics than FRS, they even share frequencies. For your license fee, you get to use higher power, repeater operation is permitted, and there are (I believe) 8 additional channels (22 vs 14). <hr /></blockquote>Correct. The advantage GMRS gives you is high power. Most of the GMRS radios are dual band, so they have the FRS frequencies also. I think these radios are generally better quality, so a dual band radio on FRS frequencies may work a lot better than a cheapo "FRS only" radio. In radios, you get what you pay for. You wouldn't need the license (for the FRS freqs), and if FRS didn't work, you could switch to the high power frequencies. Also, since GMRS frequencies are not coordinated, so you would be much less likely to get in trouble using them if you were unlicensed<hr /></blockquote><hr /></blockquote>

I just don't think that lack of RF power had anything to do with your problems, because the range was so short. There had to be another reason, though I don't know what it was. I've never encountered anything like the issues you describe, so it can't be endemic to FRS. Boat-to-boat or boat-to-shore is where I've seen often seen these devices exceed their performance claims.

BTW, there are "cheap junk" GMRS handhelds just like there are such in FRS. The manufacturers have taken to producing "dual-use" radios so that they can advertise "5-mile" instead of "2-mile" range, but selling them in toy stores. Parents buy them for their kids and never see the fine print that notes you're supposed to have a license. For this reason, I don't see GMRS remaining exclusive very long - it will become like CB; they'll finally throw up their hands and open it up unlicensed to everyone.

Remember when you used to have to be 18 years old, and have an FCC-issued license, to talk on CB?

SpiderMan

SpiderMan
01-12-2005, 03:33 PM
Barbara,

What is the model number? We can look it up on the RatShack web site.

SpiderMan

Barbara
01-12-2005, 04:08 PM
Spidey,

I posted a link to it in my "EDITED" post below. Check it out!

Barbara

SpiderMan
01-12-2005, 04:38 PM
Barbara,

The device you linked to does not seem to match the description you posted earlier. You mentioned raising up an antenna, and this unit does not have an antenna.

It is one of the devices I mentioned that sends the signal through your house wiring. Range is about 300 feet max, and all units must be plugged into receptacles that are on the same phase of your incoming power. Otherwise, they will be isolated by your outside transformer and won't hear one another.

http://www.radioshack.com/product.asp?cookie%5Ftest=1&amp;catalog%5Fname=CTLG&amp;ca tegory%5Fname=CTLG%5F008%5F005%5F002%5F000&amp;product %5Fid=43%2D3105#

SpiderMan

Barbara
01-12-2005, 04:49 PM
Spidey,

My bad, our intercoms don't have an antenna. I'm thinking of our cordless phones whose handsets have antennas.

But Radio Shack does have a neat-looking 3-way intercom system - a lot slicker-looking than the 2-way we bought 6 years ago. Too bad it's got a shorter range than what SPetty needs.

BTW, I couldn't open up your link. The cookies were choking me.

Barbara

highsea
01-12-2005, 08:34 PM
Circuit City has a GE wireless intercom that uses FRS radio. They have an optional portable that you can add-on to the system that charges from the base unit.

http://www.circuitcity.com/ccd/productDetail.do?oid=80337&amp;WT.mc_n=66&amp;WT.mc_t=U

Radio Shack has a 900 mhz one:

http://www.radioshack.com/product.asp?catalog_name=CTLG&amp;category_name=CTLG_0 02_004_000_000&amp;product_id=43-3102

The FRS one would have greater range. Some 900 mhz cordless phones also have built in intercoms.
_________________________________________

sack316
01-12-2005, 11:19 PM
not sure what capacity you plan on using them in, but if it's in a business sense and you could use cell phones as well there's always the Nextel/Southern Linc/ whatever service in your are with direct connect. it's always been pretty expensive, but I think they have come up with cheaper plans now designed more for direct connect usage. Like I said, not sure HOW you plan on using this, so I may be way off base. Just thought I'd throw something different out there.
Oh, and also if I'm not mistaken, any two way that is capable of over 2 miles technically requires a license. Again I say... technically.

highsea
01-13-2005, 02:54 AM
<blockquote><font class="small">Quote sack316:</font><hr>Oh, and also if I'm not mistaken, any two way that is capable of over 2 miles technically requires a license. Again I say... technically. <hr /></blockquote>
That really does depend on the frequency. CB's, Marine VHF's, and Aviation radios do not require individual licenses, and all can reach well beyond 2 miles.

SPetty
01-13-2005, 09:23 AM
<blockquote><font class="small">Quote highsea:</font><hr> Some 900 mhz cordless phones also have built in intercoms.<hr /></blockquote>There ya go. That would actually solve two problems... /ccboard/images/graemlins/smile.gif Can we explore this a little?

I bought a cordless phone specifically for use in the Pool Hall. I put the base station in the window at the house trying to get a better line-of-sight. The remote phone rings, but the reception is horrible. The only thing I can use it for is to answer the phone and ask the person to hang on while I run to the house to get the "real" phone. I don't think they can understand me over the static, and I know I can barely understand them. The reception doesn't seem to get better as I make it towards the house, where I know I'm in direct line with the antenna. I've since unplugged it because it was actually worse to answer it than to just let the caller leave a message.

So, do you think a cordless phone with built-in intercom might be the answer? Any recommendations on the very best cordless phone? Is 900MHz the best cordless phone I can get?

Chopstick
01-13-2005, 09:46 AM
<blockquote><font class="small">Quote SPetty:</font><hr>
So, do you think a cordless phone with built-in intercom might be the answer? Any recommendations on the very best cordless phone? Is 900MHz the best cordless phone I can get?
<hr /></blockquote>

900 MHZ is old news. The newer ones are much better. I bought one of the Seimens 2.4ghz phone systems. It has one base station and I bought two remotes. The base is connected to the phone line and the remotes just sit on battery charging units. It has intercom capability which I have never used since there is no one else to talk too. The catch is that WAP routers operate on that frequency if you happen to have one. The last time I looked there were making remote phone systems in the 5 ghz range. These would be better. The reason I didn't buy one is they didn't cost enough. If it's too cheap I can't believe that it would work good. My 2.4 has pretty good range. I think a decent one can be had for $200 or less.

By the way if you are having that much trouble keeping up with Leroy, why don't you just give him a cow bell. /ccboard/images/graemlins/laugh.gif /ccboard/images/graemlins/laugh.gif /ccboard/images/graemlins/laugh.gif

SpiderMan
01-13-2005, 10:19 AM
You can extend the range of a cordless phone substantially by adding a BNC connector to the base-station case and running a coax to an elevated antenna. The older 49-MHz phones (if you can still find one) are best suited to this type of range extension. The newer 2.4- and 5.6-GHz devices will suffer from a lot of signal attenuation in the added cable. Also, your construction techniques are less critical at the lower frequency.

Of course, you can also buy (at higher cost) higher-powered specialty cordless units.

SpiderMan

highsea
01-13-2005, 12:48 PM
<blockquote><font class="small">Quote SPetty:</font><hr> Any recommendations on the very best cordless phone? <hr /></blockquote>
These are not consumer class phones, so be prepared for a little sticker shock, but this is the best there is for range. The basic system is about 350 bucks. You can get high gain external antennas for outdoor mounting, the handsets come standard with 2 antennas, a short one for normal use and a long one for extended range. The base units have about 9 times the power of a standard cordless phone.

These phones outclass anything else out there by a bunch. The setup may be a little more complex than a normal phone. This is typical of business class communications equipment.

http://www.engeniusphones.com/engenius_sn920_ultra.htm

http://www.twacomm.com/Info/SN_920_Ultra.htm?SID=EW23XNAXPDLL8JUXRPT3PW1HNRSJ3 HKD

This may be overkill, a standard 2.4 ghz cordless has about 2.5 times the power of 900 mhz systems. Panasonic has some nice 2.4 ghz phones that are cheap and loaded with features.

SPetty
01-13-2005, 01:55 PM
<blockquote><font class="small">Quote highsea:</font><hr> http://www.engeniusphones.com/engenius_sn920_ultra.htm<hr /></blockquote> http://www.engeniusphones.com/images/sn-920_distance.jpg

As evidenced by this picture from their web site, it's obvious that their phone can reach all the way from the house to the barn!!! /ccboard/images/graemlins/laugh.gif

highsea
01-13-2005, 02:23 PM
Lol, that's some house, too. Looks like a Victorian Mansion that's defended by a couple ICBM's. /ccboard/images/graemlins/grin.gif

SPetty
01-13-2005, 04:28 PM
Okay, how about something like this?

Wireless Phone Jack System (http://www.homedepot.com/prel80/HDUS/EN_US/shop_cart/pg_print_product.jsp?CNTTYPE=PROD_META&amp;CNTKEY=shop _cart/pg_print_product.jsp&amp;BV_SessionID=@@@@0975779970.1 105658624@@@@&amp;BV_EngineID=cceladddijedfkkcgelceffd fgidgkk.0&amp;MID=9876&amp;prod_id=161275)

All the buildings are on the same transformer, so that's like on the same line, right?

This could get me a phone in the pool hall, and even internet access since I'm on dialup, and surely I can find "hard wired" phone sets with an intercom feature, you think?

highsea
01-13-2005, 04:44 PM
<blockquote><font class="small">Quote SPetty:</font><hr> All the buildings are on the same transformer, so that's like on the same line, right? <hr /></blockquote>Do the outbuildings draw service from the house? Or do they have a separate service from the transformer?

My guess is that if they are on separate services, it will not work.

Regarding internet access, 802.11b uses 2.4 ghz DSSS technology, so you may be able to use wireless network adapters to share your dial-up connection if you get a wireless router/firewall with a POTS connection.

Rod
01-13-2005, 05:25 PM
Well lets not forget the silo in case your out there shoveling wheat. /ccboard/images/graemlins/laugh.gif They didn't space those trees right either and the silo is to close to the barn.

HTH