Some Starlink users say they’re running into overheating issues during the beta of SpaceX’s new low-orbit satellite broadband service.
Starlink is currently providing 10,000 beta participants speeds between 50Mbps and 150Mbps. Users pay $100 per month (plus a $500 hardware charge) for the next-gen broadband service, which Elon Musk claims will see a broader commercial launch before the end of 2021.
But according to user complaints on Reddit, the Starlink satellite dish user terminal, affectionately dubbed “Dishy McFlatface” by SpaceX, is experiencing temperature issues for some users. Reddit user SocietyTomorrow stated that his broadband connection shut down at noon in the Arizona Summer sun, only to kick back on again after being sprayed with a hose.
“I did submit a ticket and they only said it will shut down at 122 [degrees],” the user wrote. “Sadly tomorrow will be 122, and Wednesday will be 123. Dishy is already out at 112 so [I’m] gonna be quiet at home while I work out a solution.”
"Thermal shutdowns had not happened until about a week ago for maybe a few minutes at a time in the afternoon, now it happens most days since then, but for short periods," SocietyTomorrow told Motherboard in a Reddit direct message. "Our record breaking days for the last few days however has left it shut down from around 11AM to 7PM. It would come back briefly, but my educated guess is that the outdoor temperature is a major contributing factor, the interior motors for satellite targeting push it over the edge."
SocietyTomorrow, who works for a small business that offers printer and electronics repair, said that he signed up for Starlink because the only competition in his area had top advertised speeds of 10 Mbps. There were wireless internet service providers that offered speeds in the 25-50 Mbps range, but at around $150 a month.
"Starlink is the obvious choice at least for the next couple years," he said.
Another Reddit user in central Virginia complained about Dishy overheating at temperatures in the lower 80s. It’s unclear how widespread the problem is, and SpaceX did not respond to a Motherboard request for comment on the scope of the complaints.
Last November Oregon-based engineer Ken Keiter posted a 55-minute teardown video of Dishy over at his YouTube channel, telling viewers that it was “rare to see something of this complexity in a consumer product.” Keiter told Motherboard that while reasonable consideration was given to heat dissipation in Dishy’s design, he could see the potential for problems.
“The phased array assembly comprises a PCBA (printed circuit board assembly) adhered to an aluminum backplate which serves several purposes—acting as RF shielding, providing structural rigidity and, most relevantly, acting as a radiative thermal mass (heat sink) for the components on the PCBA,” Keiter said.
Heat is funneled from the circuit board to the aluminum backplate using a foam-like thermal interface material (TIM). The backplate itself resides in a weather-sealed cavity containing a small amount of air. As this backplate heats up, the air surrounding it also heats, transferring thermal energy via the plastic enclosure to the outside environment, Keiter said.
“Here's the problem: at some point, the rate at which the combined thermal energy being absorbed by Dishy's face and being dumped by the components into the backplate, the air surrounding it, and the enclosure exceeds the rate at which that that energy can be dissipated to the outside environment,” he noted.
Electrical components like resistors, capacitors, and diodes are usually rated for operation within certain temperature ranges. According to the Dishy technical specifics obtained by Starlink beta users, Dishy’s optimal operating temperature is between -22°F to 104°F. Going beyond that in either direction will trigger what Keiter called “Dishy's self-protective instincts.”
Obviously resolving issues like this is what betas are for, and Keiter sees three options Starlink could pursue before a broader commercial launch.
Engineers could change Dishy’s mechanical design to achieve better heat rejection, change the dish’s electrical components to expand its thermal operating window, or develop a feature that allows Dishy’s components to operate at reduced power to create less heat. He noted the latter two options would likely be taller orders.
“If changes to Dishy's mechanical design are insufficient to reject heat at a rate exceeding its ability to produce it, software changes will be required to make the system more thermally efficient,” Keiter said. “But if speed limiting and system optimization can’t fix the issue, it will require a significant hardware revision for the commercial launch.”
“Since they've got a lot of custom silicon in there—likely the limiting factor—the turnaround time on this would be very slow,” he added. “They could resort to some form of active heat removal like fans or thermoelectric cooling, but then they burn a ton of power which would make Dishy even more power hungry than it already is.”
“This is a really tricky engineering problem with some insanely tight constraints,” Keiter said. “The good news is that the team is pretty sharp.”
Assuming the kinks are worked out before a broader commercial launch, Starlink should be a welcome option for some of the estimated 42 million U.S. residents who lack access to broadband. Millions more Americans have been stuck on traditional satellite broadband service, which historically features notably slower speeds at significantly higher latencies.
Still, Wall Street analysts say that the laws of physics mean Starlink won’t pose a serious threat to incumbent fixed line broadband providers like Comcast, Verizon, or AT&T, or the massive regional monopolies such giants enjoy. At a conference last year Musk acknowledged the service won’t have the capacity needed to serve dense population centers.
Telecom analyst Craig Moffett recently estimated that once the company launches all 12,000 low-orbit satellites, capacity constraints will initially limit availability to somewhere between 300,000 and 800,000 users, less than 1 percent of the US broadband market. Fewer if the company runs into hardware supply chain constraints.
This story has been updated with comment from SocietyTomorrow.
Emanuel Maiberg contributed reporting.