Hyperchat Tower

Built to receive Hyperchat signals in normal space, Hyperchat Towers are buildings that house the sensors needed to eavesdrop on hyperspace. Where normal sensors simply try to pick up everything of relevance, these towers are finetuned to solely pick up Hyperchat signals.
There are a few big bonuses to Hyperchat Towers over their alternatives. First of all, they are simply far cheaper to run. Not needing to be located in hyperspace, which means they do not need a hyperdrive to operate but can use normal powerplants. This means a small base can afford to recieve Hyperchat signals even if it's too expensive to broadcast any in return.
A more obscure benefit is that unlike normal sensors, the towers are quiet themselves. A normal sensor array can be detected from Hyperspace, while a tower cannot. This helps with corporate espionage through means such as eavesdropping, relays for secret message signals, as well as being able to detect a passing fleet. One example is during the War of the Fishes, when Roya had an automated trap lying in wait in normal space. When the Hyperchat Tower detected the nearby ships, the automaton ships jumped into the Hypersea and attacked the passing ships.
Of course the biggest downside is that a Hyperchat Tower cannot broadcast itself. Additionally, since it is not located in hyperspace, a Hypersea Base cannot target it unless its exact coordinates are known. A passing ship won't know where it is, so cannot relay signals. The common solution to this conundrum is a small beacon that sends out infrequent pings. As the beacon only operates every few minutes, it consumes far less fuel than a constantly active hyperdrive would. Granted, this does mean every passing pirate also knows where to find you, so better have some weapons at the ready.