Looking for input on ordering circuits from Qwest for some circuits for a voting system.
There will be several receivers and the main local receiver.
Will be using MTR's into a JPS.
I had a telco tech tell me 0 loss lines...
LeasedLine options
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psapengineer
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Leased Lines and Voters
Hi,
The JPS voter, with it's recommended settings, votes based on the amount of high frequency (voice) noise; somewhere in the range of 2300-3000Hz or so.
Using leased copper lines will often produce high frequency rolloff rendering the voter's decision making process very impaired. Mixing of T1 or Microwave circuits and copper lines will make the problem worse.
If you must use copper leased lines I recommend that you order a 2 or 4 Wire "C2" conditioned circuit. The C2 conditioning will, to some degree, help control the roll off. R3002 voice grade lines will likely not be good enough.
Also, remember to make the squelch very tight (better than 12DB SINAD), use AND squelch, and test to know where each Rx squelch closes on low carrier levels to insure that the voter isn't presented with really bad audio for the decision making process.
Good Luck, Bob
The JPS voter, with it's recommended settings, votes based on the amount of high frequency (voice) noise; somewhere in the range of 2300-3000Hz or so.
Using leased copper lines will often produce high frequency rolloff rendering the voter's decision making process very impaired. Mixing of T1 or Microwave circuits and copper lines will make the problem worse.
If you must use copper leased lines I recommend that you order a 2 or 4 Wire "C2" conditioned circuit. The C2 conditioning will, to some degree, help control the roll off. R3002 voice grade lines will likely not be good enough.
Also, remember to make the squelch very tight (better than 12DB SINAD), use AND squelch, and test to know where each Rx squelch closes on low carrier levels to insure that the voter isn't presented with really bad audio for the decision making process.
Good Luck, Bob
Last edited by psapengineer on Sun May 13, 2007 6:48 pm, edited 1 time in total.
My two bits worth:
I completely agree with Bobs comments.
Another thing to consider is the "Latency" of your circuits.
Be careful that some of your circuits do not go via any sort of digital circuit.
The JPS manual warns that there will be problems if the audio does not arrive at each signal port at more or less the same time. There is an adjustment for a certain amount of delay.
If all circuits are on fiber, or other digital system the local receiver can be "loop back" on a circuit to give the same audio characteristics and delay as the others.
I like the JPS voter.
I completely agree with Bobs comments.
Another thing to consider is the "Latency" of your circuits.
Be careful that some of your circuits do not go via any sort of digital circuit.
The JPS manual warns that there will be problems if the audio does not arrive at each signal port at more or less the same time. There is an adjustment for a certain amount of delay.
If all circuits are on fiber, or other digital system the local receiver can be "loop back" on a circuit to give the same audio characteristics and delay as the others.
I like the JPS voter.
Aloha, Bernie