Dialing in to ISDN advice?

[MikeShannon914]

OK, let's say you're at a station that has an ISDN line, and it goes through what's basically a "blue box" that's installed in a rack. Do you have to have a blue box at the other end to "talk" to it? Or is there a computer program that will do the same thing? The box at the station (in the rack) has a dial-in/dial=out number. Seems like there's an option on it for taking an analog feed as well. I know very little about this stuff, but we're talking AM here and the audio doesn't have to be pristine. Any ideas?

 

[Robert Bass]

Hey Mike,

Is this so you can do your Hi-FI club show away from the studio? By the way, congrats!

My limitied understanding of ISDN is that it's somewhat similar to using a POTS Codec. But because of the way it works, you need a dedicated ISDN line (think $$$) from point A to point B. With a POTS unit, all you need is a plain old telephone line, and a box at both ends. These things usually work very well, as long as neither end of the connection is using a phone line on a PBX phone system.

Another option is to use IP streaming using equipment from such places as TieLine. IP technology is about the same as a POTS Codec. It's a stand alone unit that is automatically able to connect from one site to another, vis an IP port #.

In both cases, all you really need is either a simple, inexpensive POTS phone line to use a POTS Codec, or high speed Cable/DSL internet access to use IP. One word of caution though, IP streaming will have a delay. A good POTS Codec such as what Comrex has, is very real-time, with a delay of less than half a second.

R

 

[ISaidSo]

Don't think Blue box uses ISDN... Just a standard pots line.. YOU will need a blue box on the other end for it to work though..

 

[Nashsound]

If it is a Comrex Blue Box, any of the Comrex POTS codecs will talk to it- Matrix, Vector, or Hotline. BB took the Hotline's place in the product line, so you may be able to find a used one reasonably priced.

 

[BKane]

I've dealt with talk show remotes using Hotline. The sound quality was often terrible. POTS would have been better.

For anything with music (yes, even on AM), you need ISDN on each end.

The Telos Zephyr is good: http://www.telos-systems.com/?/zephyr/default.htm.

But it'll cost $$$ for the machine and ISDN line.

BK

If it is a Comrex Blue Box, any of the Comrex POTS codecs will talk to it- Matrix, Vector, or Hotline. BB took the Hotline's place in the product line, so you may be able to find a used one reasonably priced.

 

[Holstead]

It is pretty easy to find good used ISDN gear. The old Telos boxes still do the same thing as the new ones, you just have through a few more steps. If in good condition, they still sound great.

 

[Robert Bass]

I've dealt with talk show remotes using Hotline. The sound quality was often terrible. POTS would have been better.

For anything with music (yes, even on AM), you need ISDN on each end.

Not necessarily.

The Comrex gear has two different Codec modes. One is intended for music quality, the other is a combination of voice and data. The music mode is very, very good, even at 16.8 baud. The voice mode is designed for sending both audio and data simultaneously. The tradeoff is audio that doesn’t sound quite as good.

R

 

[Eye]

The actual ISDN line is an added expense. I'm currently paying about $70 a month through AT&T.

 

[OKCRadioGuy]

ISDN

ISDN would be the most stable and best sounding way to go. With that being said you'll pay 70 bucks a month to have the service, plus an install fee that sometimes can be reduced for a long-term commitment for service. In many places (but luckily not around our part of the country yet) the phone companies are refusing to install any new ISDN circuits as it's a pain in their ass and very few folks use the service anymore except for broadcast folks and some people that do live teleconferencing. ISDN is point-to-point so it's inherenetly better for broadcast than the publically switched internet. There's more bandwidth to utilize than any pots line.

With that being said, the Tieline POTS stuff is a VERY good solution and less trouble to utilize. I've never been a fan of the Comrex POTS stuff at all. They have more trouble staying connected and sound like crap.


If you are going to get a ISDN codec try to get a Telos Zephr of some sorts. They are compatible with most other models out there and offer different modes (that sound good).

Hope this helps.

 

[317C50KW]

For quality remote audio 24/7 it's ISDN. I've been using it since the early 90's. There are some newer IP to IP solutions for audio out there that sound good but still have latency issues that won't work in a live broadcast situations.

Comrex VS Tieline. The eternal debate. I've used both this season for high school football and the winner hands down over DFW area POTS lines: Comrex Bluebox. Tieline is good but I could never coax more than a 9600 bit rate out of it (there were some station related issues involved that I won't bring up in a public forum).

The Bluebox is a monster improvement over Comrex Hotline. Two dixie cups and a string were an improvement over Hotliine.

 

[OKCRadioGuy]

.... Two dixie cups and a string were an improvement over Hotliine.

You got that right. The old Hotline units are truely a P.O.S.

 

[CW]

The actual ISDN line is an added expense. I'm currently paying about $70 a month through AT&T.

Depends on the state...in Texas, ATT's rate for BRI ISDN is $55 a month on a 2yr contract with no other fee.
Of course that doesnt include tax, etc....IF you go shorter term, you must pay an engineering fee up to $250.

 

[CW]

Hey Mike,

Is this so you can do your Hi-FI club show away from the studio? By the way, congrats!

My limitied understanding of ISDN is that it's somewhat similar to using a POTS Codec. But because of the way it works, you need a dedicated ISDN line (think $$$) from point A to point B. With a POTS unit, all you need is a plain old telephone line, and a box at both ends. These things usually work very well, as long as neither end of the connection is using a phone line on a PBX phone system.

Another option is to use IP streaming using equipment from such places as TieLine. IP technology is about the same as a POTS Codec. It's a stand alone unit that is automatically able to connect from one site to another, vis an IP port #.

In both cases, all you really need is either a simple, inexpensive POTS phone line to use a POTS Codec, or high speed Cable/DSL internet access to use IP. One word of caution though, IP streaming will have a delay. A good POTS Codec such as what Comrex has, is very real-time, with a delay of less than half a second.

R

Two flavors of ISDN...BRI and PRI. BRI is what most broadcast users run...it consists of 2B+D channels...The B or Bearer channels are 64KBs each...the D or Data channel is 16KBs. The D channel handles all the call info, setup, knockdown, etc..the B channels just handle the data (in this case digitized audio). For a uncompressed circuit, a B channel is good only for 4 kHz bandwidth...thus two combined would give you 8 kHz (PCM mode)...in MPEG or other compression schemes, you get up to 20 kHz stereo (and remember this is bi-directional). There is a latency issue with ISDN but not as bad as IP or other schemes (worse is Layer 3 Joint Stereo which can run about 250ms or so).

You can run a Codec like the Zephyr OR go with Adtran ISDN boxes that talk V.35 to external codecs like the Musicam 1000 or similar which do APT-X or similar compression. I have bought two Adtrans for less than $25 each. The codec was another price Some boxes will talk to others IF you have the switch settings right (A Zephyr to a Musicam for instance) but NOT always, though with most now going MPEG as standard, this is less of a problem. BRI ISDN can be dialed switched like POTS and thus can be used to call other BRI sites at any time. In data/voice mode, you can use it to get 144kBs of data to the internet OR one voice grade line and 64+ kbs of data OR two voice grade lines and up to 9600 baud of continuous data. Its all how you mix/slice it. ISDN BRI was to be the next step in residential home phone service to replace POTS..but it never happened because of pricing. BRI modems 10 years ago costs over $1500..now you can get one for $20 (such as a Cisco 800 series)...still wrapped in plastic. For those who cannot get DSL or dont want cable, ISDN BRI can be installed ANYWHERE POTS can go so it is a nice alternative to dialup and you can get 128 dynamic connections to the internet (get a voice call and it backs down to 64k automatically...hangup, and you're back to 128k...in both directions; sure beats 33 or 48k dialup)

ISDN PRI is 23Bs and 1D channel. It is a point to point and used primarily for PBX to Telco service (with Caller ID and other digital services) and between Telcos (using the SS7 switching network). It is not used for broadcast except maybe in video conferencing. A PRI is really a T1 but with common channel signaling in the one D channel and the full 64 kbs is used in the B channels (a T1 has signaling in every 64kbs time slot DS0 when used in voice..if used in the clear channel data mode, it does not and the entire T1 is used for the data stream)