After successful demonstrations in May 1941, the system was ordered into production and several hundred examples were produced by Research Enterprises Limited in Toronto.

Two upgrades were made over the year-long production run, the SW2C which moved to a slightly higher frequency, and the SW3C which used a motorized antenna and PPI display.

In early 1939, the British government invited teams from Canada, Australia, New Zealand and South Africa to visit the UK to be briefed on the then highly secret developments in radar.

Shortly thereafter, the Royal Canadian Navy (RCN) asked the NRC to provide a better way to look for submarines sneaking into Halifax Harbour.

[2] In October 1940, while en route to Washington, DC, members of the Tizard Mission stopped in Ottawa to provide them with updates on their progress in the UK.

The ASV's transmitter was adapted to operate using US and Canadian vacuum tubes in place of the Philips designs used in the British sets, and plans for large production runs for sale to the US Navy began at Research Enterprises Limited (REL) in Toronto.

A follow-up meeting on 19 March concluded that while using the much shorter wavelengths from the cavity magnetron shown to them by the Mission would be preferable for many reasons, too much basic development was still needed before it could be used operationally.

[6] The resulting system, known as CSC, was developed and installed in a remarkably short 54 days, beginning sea trials aboard HMCS Chambly on 12 May 1941.

Based on manual plotting and dead reckoning, the ship's captain, Commander James D. Prentice, insisted it was 28 degrees to one side.

[7] In service, problems became immediately apparent; the antenna system often produced false echos, sometimes on the opposite side of the ship, and the long pulse duration meant it could not see anything within half a mile.

[7] Worse, while the system worked well in calm seas, in the mid-Atlantic swells it proved to be filled with noise from reflections of waves, making it difficult or impossible to see a U-boat if it was properly trimmed so only the conning tower was above water.

This was further hindered by the RCN's habit of sending new recruits to serve in the labs and as operators, in contrast to the Royal Navy, which sent its most experienced men to these posts.

[7] These issues, combined with a number of poorly thought-out features, resulted in the system being considered a maintenance nuisance throughout its time in service.

The rotation system, in particular, was notoriously unreliable; in one instance a naval rating was detailed to the roof to turn the antenna manually with a pipe wrench when the linkage failed while trying to navigate through a convoy.

[7] The Royal Navy attempted to help by taking over maintenance when Canadian ships arrived in Derry, but this was so time consuming the Admiralty suggested they simply be scrapped.

[9] Starting in September 1941, there were efforts to motorize the antenna display at the masthead to replace the unreliable mechanical linkage, but weight was a problem.

[12] Unknown to the RCN at the time, the UK had already developed a dramatically improved surface search radar, the microwave-frequency Type 271.

The Admiralty recalled all of the Canadian ships to UK docks and began fitting them with 271 and huff-duff, as well as giving the crews time to train on land while waiting for the refits to complete.