Canadian Centurion tanks intercom system?

[David Herbert]

JD9 is the 9th variant of a "junction distribution" box. Basically a router for the radios and intercom (IC) system.
RBJ is the "rotary base junction" which is the unit in the bottom of the turret which connects the electrical services including radio and intercom between the rotating turret and the stationary hull. It contains a lot of copper slip rings and carbon brushes and is the limiting factor of how many radio functions can be routed between the hull and the turret. In WW2 British tanks that had hydraulic turret traverse powered from an engine driven pump the hydraulic circuit went via the RBJ too, making it even more complicated.

David

[Dan Martel]

Originally Posted by David Herbert

JD9 is the 9th variant of a "junction distribution" box.

RBJ is the "rotary base junction."

Great response. Thanks very much.

Dan.

[David Wilkinson]

Sorry I was off for a while. Good info here. In the regular army, the US family of radios replaced the Brit C42 in the middle 60's. In most vehicle installations, except the Centurion, the American harness was used. This included the Ferret. Only in the Centurion was the total Brit harness retained till the Centurion was withdrawn from service. The junction between the US radio system and the Brit harness was done at the JD9. So all Canadian Centurions retained all the original junction boxes and wiring, headsets and handsets, tanoy microphone, IT telephone and reels cable with the green hornet hand set.

[David Wilkinson]

In addition. Gun tanks were equipped with 1 x 46 set (A) and 1 x 25 set (B) which could be quickly dismounted to use as a man pack. Command tanks had 2 x 46 sets plus a UHF man pack (can't remember the name) for ground air comms.
Most command tanks were equipped with the Canadian NavAid. I had one for three years and it never worked.

[chris vickery]

VRC series radio gear is certainly a lot easier to come by in serviceable condition...

[Dan Martel]

Originally Posted by David Wilkinson

Most command tanks were equipped with the Canadian NavAid. I had one for three years and it never worked.

David,

Can you tell us more about NAVAID?

Thanks,
Dan.

[Ed Storey]

See this thread on NAVAID.

http://www.mapleleafup.net/forums/sh...ghlight=navaid

[David Wilkinson]

I couldn't get the link to work.

Navaid was a Canadian development in the 1960's. It was way ahead of its time but frought with mechanical and electronic problems. Plus, it took up alot of space even in the tank (saw it mounted in the Ferret-not much room for crew!). The gyro was a Sperry ship's unit. Very large and occupied a turret floor ammo bin directly behind the driver. The turret stowage was reconfigured to allow for the electronics and a large mechanical map board which was horizontal and mounted between the loader and comd. The map board had a ball resolver and a lighted arrow. This would crawl along under the 1/50k map and project an arrow through the map sheet with the location and direction of the tank. The ball was driven by the speedometer and the gyro compass. The technical limitations of the system were extensive.

The best use of the map board was as a work space for the loader to make peanut butter sandwiches for the crew! We used to say that we got the Brits back for selling us the agony wagon, by selling them Navaid. They were the only foreign sale.