Engineers at KPBS-TV report that their HDTV service is finally back on-the-air after a fatal failure of their encoder in July took it down. Dust off your remote and check out this battle story.
Early adopters of HDTV viewing in San Diego have long used KPBS-DT as their home system demo channel. It’s the only San Diego channel that outputs true high definition video 24 hours per day. And since the program material is commonly travel logs, music concerts, and nature shows, MPEG compression is kind to it. The video looks smashing. Enlightened consumer video dealers like Circuit City favored the channel for demonstration of their monitors because it was always there and it never showed a commercial for one of their competitors.
But that all came to a dead halt July 16 this year as the station’s first generation General Instruments encoder stopped outputting properly formatted bits. The video went blank, and audio sputtered on and off. Viewers reported that it would lock up their tuners.
The station continued, airing a simple digital simulcast of their analog content.
Director of Engineering Leon Messenie took time out from his winter vacation to chat about their troubles.
GS: Your old GI HDTV encoder broke down several months ago. Tell us about the battle getting a replacement.
LM: We actually started looking for a new ATSC encoder system after learning it was going to take about $325,000 to upgrade our current system to be able to handle Closed Captions on the standard definition channels. Since a complete new system would be much less we decided to replace our entire encoding system. I applied to CPB (Corporation for Public Broadcasting) in early 2005 for a grant to replace our old and out dated ATSC encoder system. KPBS was awarded a grant and after looking at several systems we selected the Tandberg equipment. This work was started a few months before the HD encoder had the major failure. This brings us up to late August 2005 when we put in the order with Signasys Inc, a system integrator, to replace our current GI system with the new Tandberg system. That very same week our HD encoder had the major failure. According to Motorola it was going to cost $9600 to repair and had a 6-8 week turn around time. Since we had just ordered a new Tandberg system that was supposed to be delivered in 6-8 weeks I could not see spending the money to fix the GI HD Encoder.
Then the delays from Tandberg kept coming and before you know it our HD was off the air from till December 22. All we could do is continue to broadcast the HD schedule in standard sefinition and wait until the new system arrived.
GS: I understand your Tandberg replacement didn’t work on the bench. Do you have any idea of when it will finally be up again?
LM: This is correct. The new system had a couple pieces fail right out of the box. Unfortunately they were the multiplexers, both main and backup. They had to go back to the factory via a stop in Atlanta, Tandberg’s USA headquarters. We were really trying to get the HD service up by Christmas 2005….
KPBS applied for an emergency grant from their foundation. When they got the funding this fall, the station ordered a Tandberg encoder and multiplexer. The unit arrived in early December, but on the bench, it appeared to be the victim of infant mortality. A replacement arrived just days before Christmas. After a hectic few days of testing, they were able to go to air December 23—about 160 days after the HD outage. Engineer Scott Stinson is still fine-tuning, and configuring the multiplexer for a flexible set of subchannels.
