Analog interface to a T1

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efc
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Analog interface to a T1

Post by efc »

Hello,

Need to interface some Legacy equipment to a T1 line,which would go between 2 towns.So,radio analog,to a T1,then on the other end ,you would from T1 back to analog.This is going to be done to interface 2 customers together,so that customer A,would control not only their equipment,but radio equipment 20 miles away.T1 seems like a good interface,and when A T T came out,I asked them if they had like a smart jack for me to plug in the Analog input.They said no,and that I would have to have a Gateway ,and a Router.Never had to do this before,so I am looking for input.

THANKS!
John
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Bill_G
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Re: Analog interface to a T1

Post by Bill_G »

So, you need a landline service rather than a microwave? Getting a new T1 might be difficult. Most of the carriers are refusing new circuits, and want you to switch to a digital service. Is there a reason you prefer a T1 over an ip connection?
Dorf411
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Re: Analog interface to a T1

Post by Dorf411 »

In 2 applications we used Bayley MUX equipment over a T-1 with I think an FXS or FXO card I don't recall which one, the telco card was capable of being setup as a 4 wire full duplex circuit and it has worked great so far. I don't know if Bayley is still available but I think RAD makes some similar products. More recently I did a similar setup but this time I used the 2 channel Zetron Radio over IP box and it was extremely easy to configure and has been working great. The thought of the Bayley product having a problem makes me cringe as the configuration was very complex and difficult and would highly suggest you consider some type of ROIP product.
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Bill_G
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Re: Analog interface to a T1

Post by Bill_G »

FXO and FXS would be the hard way to do it. Those are meant to extend telephone service to a remote location. ie: Your company has a PBX and a published mainline the public calls, an attendant answers, and then transfers the call to an extension. That extension can be on premise, or off premise. If off premise, it gets inserted into a FXS (foreign exchange station) card that connects back to the phone company, gets to the remote location, and terminates on the FXO (foreign exchange office) card which provides a port for a POTS phone to plug in. I'm sure it would work fine as a radio control circuit, but normally we use E&M cards to carry radio traffic, and FXS/FXO cards to provide phone service at the site.
Dorf411
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Re: Analog interface to a T1

Post by Dorf411 »

Yeah, I think now that you mention it the card was an 8 channel E&M as it had signaling but we just used the 4 wire audio and skipped the other stuff.
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Bill_G
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Re: Analog interface to a T1

Post by Bill_G »

Most of us don't need the E or the M either, but it's there, and available just in case you do. I've used them for sending site alarm closures back to the prime site. And if that's the card you ask for, you're reasonably certain to get one that will work for radio control circuits. FXS/FXO cards have their place, but their days are numbered as everything goes ip.
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efc
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Re: Analog interface to a T1

Post by efc »

1.we are also,sorry,I AM ALSO INSTALLING the Zetron equipmentioned already mentioned,as a back up.

2. The T 1 is already In stalled ,and guess who is supposed to make it work .

3.when I went over with the sales person what was supposed to be installed,I guess there was confusion about the T 1.In other words,no one listened to me,oh it will work.

4.I found some Cisco equipment that looks like it connects LMR to each other.

So,since I am not familiar with this,not sure what is best solution.

Good talking to you again Bill,thanks both of you for input.
John
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efc
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Re: Analog interface to a T1

Post by efc »

Yes by the way,Microwave,WAS A SOLUTION. :o
John
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efc
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Re: Analog interface to a T1

Post by efc »

Key word,WAS :o
John
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d119
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Re: Analog interface to a T1

Post by d119 »

Seems to me a properly configured Zhone or TeNSr channel bank would handle this fine, the stuff is readily available on eBay...
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Bill_G
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Re: Analog interface to a T1

Post by Bill_G »

Yeah. The key phrase is "properly configured". A Zhone / TenSR is no bowl of Cheerios first time out.

So efc - You got a T1. You could go the route of putting in a pair of Cisco 2911 routers with T1/E1 WAN cards, get them connected, and then use the T1 to transport ip traffic. That would be the modern way of doing it rather than trying to learn Zhone channel banks. You would have to get some background in Cisco routers, or at least hire someone to configure them for you. OR you could get a pair of Kentrox DSU's. Think of them as T1 modems. Fairly easy to configure. IP in, T1 out to the telco, over to the far end to the other Kentrox, that spits out IP again. You can put the Zetron boxes on the IP side of the routers or the DSU's.
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Re: Analog interface to a T1

Post by arnu »

If you simply want to send audio - PTT and COR over the T1 - you could use a Cisco router on each end - A "old" 2611XM with a T1 card and a VIC-2E&M card. LMR configuration does the trick. It basically behaves like two analog lines with 4 wire audio and radio signalling on both sides. If you decide later to use a different connection - i.e Internet etc. switching it over is a 10 minute job. As Bill mentioned you will need some Cisco background since it is all command line based.
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efc
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Re: Analog interface to a T1

Post by efc »

Great info guys,THANKS I knew I could get some good inpu.Need it now that it is MY BABY
John
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efc
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Re: Analog interface to a T1

Post by efc »

Ok,since I am unfamiliar with this equipment,Kentrox,is the a 4 wire input,which then it digitized it for T1?
Because basically I need to go from Analog audio,from a radio console,to the other end which is the back of a JPS voter.

Thanks
John
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Bill_G
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Re: Analog interface to a T1

Post by Bill_G »

Ah. You never mentioned a voter. And I thought you said you were going to use Zetron roip boxes. The Kentrox is an ethernet to T1 converter which would be a good fit for carrying the Zetrons over T1. Is that a little clearer? To interface analog stuff to a T1, you need E&M cards which brings you back full circle to buying a pair of MUX's (channel banks) like a Zhone, or a Motorola TenSR, or a RAD, with E&M cards installed, and a WAN card to plug the T1 into at both ends.

You have the T1. Make a commitment to either carry the traffic the old fashioned way with channel banks, or the more modern way with roip. Don't mix them especially if you're using a voter. If you want best voter performance, do it the old way. It has the least latency, the best audio performance, but the most cost, and the most configuration.
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efc
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Re: Analog interface to a T1

Post by efc »

Yea,sorry I did not make myself clear.Yea ,I will probably tell the sales guy that we need to use the Zetron as the primary method,and come up with another backup plan.See,the guy that sold this was thinking,T1,with some sort of interface ,as Primary communication link.Then use the Zetron through the cloud as a backup method.I thought it was going to be Zetron as the primary method,then microwave as a backup plan.But ,oh well, what are you going to do,back to the drawing board,lol.

Thanks
John
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Bill_G
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Re: Analog interface to a T1

Post by Bill_G »

I take it no one has engineered any of this, but you're supposed to build it. That's pretty harsh especially for an apprentice tech. Have you got any backup? Someone else in the shop to bounce this off of?
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efc
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Re: Analog interface to a T1

Post by efc »

Yea,there is an I T guy,who I may be able to talk to,and I was thinking,ATT,installed a unit that has CSU units in it,and it looks very familiar to the unit you told me about.I have been exposed to a lot of things through the years,but this is new to me.I understand,for the most part how this is supposed to work,but I don't know enough to know what parts I need,if that makes sense.Yea I get it,but what to you use,I was asking myself.A little frustrating it is,because I had in my mind a different scenario of what they were going to do,versus what was handed to me.
John
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d119
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Re: Analog interface to a T1

Post by d119 »

IN MY OPINION, stay away from RAD stuff. Their customer support is atrocious, Motorola pushes the stuff on people as a VAR for RAD, and half the time it's the wrong product for the job, and the stuff is just generally screwy.

Again, IN MY OPINION, I would seek out any vendor EXCEPT RAD.
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efc
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Re: Analog interface to a T1

Post by efc »

Thanks
John
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Re: Analog interface to a T1

Post by VE3HKB »

Another opinion - if you want this to be reliable and easy to support, strongly consider a proper mux (channel bank, etc.). One that I've used a lot is the Harris Intraplex. RAD isn't bad, but the support can be difficult. Bayly is out of business. For the Intraplex, you simply add cards for the signals you want to carry on your T1. Straight audio, audio + E&M, RS-232 data, ethernet, whatever. Most options are dip-switch selectable, so it's pretty simple to use. You mentioned voting - the Intraplex model has been used extensively in trunking systems with both analog and digital voting. It is "old school" technology but it works, and works well.
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Re: Analog interface to a T1

Post by mmckenna »

Might be a bit late to the conversation, but we are doing this exact same thing. A couple of voter receivers/repeaters at one site, dispatch about 2 miles away. I run the telecom network, so putting in my own T-1 circuit was cheap/easy.
Anyways, were using these, Adtran Atlas 550's: http://www.adtran.com/web/page/portal/Adtran/group/42
using Octal E&M cards: http://www.adtran.com/web/page/portal/Adtran/group/42
Point to point T-1, so no network delay issues.
-48vdc powered off our telecom network power plants.
Ethernet management interface.

Been working well for several years.
"The nice thing about standards is that there are so many to choose from."
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Re: Analog interface to a T1

Post by tsunami_australia »

Not sure how kosha it would be considered but Tiger Electronics I think it was, was making a URI (USB Radio Interconnect???) or similar to that which was a USB sound card to mic socket solution. This with something like a raspberry pi hooked to teamspeak/mumble/etc would be a cheap workable method to extend over IP. Else you may consider a pair of phone patches back to back hooked to a desk radio at each end to join the system.

Neither solution is the most appropriate but will work.

EDIT: Just a thought, whats up with a pair of ISDN phones with 600ohm couplers to the radio instead of a handpiece? As each radio connects to the other it creates a 1:1 connection between the radios.
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