• Your next clue comes from the exact display on your Pro-Link after you try to dial (note that if you are having trouble, you should NOT use a pre-set or external computer dialer; you should dial by hand directly on the Pro-Link until the trouble is isolated). After you enter the number, watch the display carefully. In a normal situation, the Pro-Link should display "Setup" and begin counting down from a number -- hopefully a number greater that 20. If the countdown is too fast, the Pro-Link will display "Connect attempt failed" and abort the call perhaps too early; if this is the case check the timeout setting (Set: Option #1, timeout value is displayed. If Timeout is less than 20 seconds, press 1 and enter a timeout of, say, 25 seconds).

If, while counting down, the display changes from "Setup" to "Waiting," the call attempt has failed. You may abort the call prior to the end of the countdown by pressing Esc. At this juncture it may be a good idea to experiment by dialing into a different site, perhaps dialing one of your own ISDN numbers in order to check the viability of your outbound calls. If you find that you can connect to others but not to the target site, continue below without restarting. If you cannot dial into your own numbers or another site, power down your Pro-Link, wait ten seconds, and restart. Try again.

• If the display changes IMMEDIATELY to "Waiting" when the call is entered, the call is failing locally. Check the viability of the number you are dialing. Try dialing into one of your own numbers. If this fails, power-cycle the Pro-Link as in the paragraph above and try again (local phone company registration errors being the suspect culprit).

• If you find that you CAN connect to other numbers (such as your own) but not the target site, your next step is to try forcing the calls over an alternate long-distance carrier. Note that all calls in any given session need to be carried by the same long-distance carrier. Force-picking a carrier is done by inserting a 10xxx code in front of the phone number, where xxx is the 3-digit code for the long-distance carrier. The call will then be dialed as, 10-XXX-1-Area Code-Phone Number. Typically, in such situations, we try the following long distance carriers, in order of preference:
10-222 (MCI)
10-333 (Sprint)
10-288 (AT&T).

• If you are unable to complete calls to the target site over any long distance carrier, and you are able to complete calls to other sites, the problem must lie with the far end site. Have them re-start their equipment. If you are still unsuccessful in this scenario after they have restarted their equipment, the far site will likely need tech support from their provider.
 
 

• "Swirling" sounds on the high end may also be time-based telco anomalies; the only cure is to redial. This is a relatively uncommon affliction.

• IMUX "chirping" may be a result of the codec’s inability to resolve the multiple lines. Again, redialing may improve this situation. Also, this is the sound you are likely to hear in the event that some calls are handled by a different long distance carrier (i.e., severe timing problems). If this persists, try using the force-pick code, starting with MCI: one or more of the originators’ lines may be defaulting to a carrier other than MCI. If this is the case A), a force-pick code on all calls will cure it and, B), you should alert EDnet so that we can have your line "re-picked" to MCI (the carrier of choice for EDnet’s affiliate network).

• If there is a high-pitched whine that does not follow modulation (i.e., it’s constant), and/or if the noise floor is higher than desired, these may be artifacts of the analog input stage of the sending unit. In any case, utilizing the DSM’s AES/EBU digital input via an external analog to digital converter or DAT machine will yield the cleanest signal chain. Barring that, sending at the hottest level possible without clipping will give you the best signal to noise ratio possible while using the analog input circuitry.