The following story is reprinted with the kind permission of Cris Alexander, CPBE, AMD, DRB, Director of Engineering at Crawford Broadcasting Company. It was first published in the April, 2025 edition of The Local Oscillator, the newsletter of Crawford Broadcasting Company Corporate Engineering.
We have for some time now enjoyed using Wheatstone-enabled Tieline Gateway codecs as primary STL audio transports in several markets. It’s great to be able to route audio directly to and from these units, and their multi-unicast features and SmartStream Plus diversity backup feature provides for seamless transition to an alternate IP path if the primary path is lost or degraded.
Nowhere do we work our Gateways harder than in our Denver market, where we have not only four primary AM signals but also four FM signals plus backup alternate IP routes. The studio Gateway 8 has the following full-time outbound connections/streams:
- KLZ Main
- KLZ SmartStream Plus backup
- KLZ FM
- KLZ FM SmartStream Plus backup
- KLTT Main
- KLTT FM
- KLVZ Day
- KLVZ 94.3 FM
- KLVZ Night
- KLVZ Night SmartStream Plus backup
- KLVZ 95.3 FM
- KLVZ 95.3 FM SmartStream Plus backup
- KLDC
We also have several inbound streams from the KLZ transmitter site for satellite feeds – all our C-band antennas and receivers are at the KLZ transmitter site, so add four mono inbound streams to the list.
That’s a lot of eggs in one basket, so we have a backup Gateway 8 in the rack, connected to both networks and ready to go with connection programs that duplicate everything in the main unit. Switching to the backup is simple: Log into both units, click connect on the backup and disconnect on the main. You’re back up with all signals in a few seconds.
But there’s one small problem with that. When we switch to the backup unit, the back-hauled satellite feeds are not routed in Wheatnet where they need to go. We always had to do that manually, which is a PITA because they go several places as static routes and occasionally to a DRR channel as a dynamic, switched route. It sure would be nice if the routing would change with which Gateway is connected.
It occurred to Amanda and me as we were discussing this that there should be a way to fire a salvo in Wheatnet with a Gateway connection. Amanda asked Tieline’s Jacob Daniluck about it and he pointed the way. It’s possible to set a “rule” in the Gateway so that a program, a connection or specific stream can trigger a Wheatstone SLIO, and he told us how to set that up. It took some trial and error, but we figured out how to make it work in Wheatnet. Now, when we go to the backup Gateway, as soon as the KLZ connection is made, it sets the static routes for the satellite backhaul.
I’m still noodling on how to deal with the switched routes (DRR). I’m thinking a script in Wheatnet…
