Flickering signals and horns at Brixton

The signals flicker and alwayts have done since the start. This is due to the way the coded track circuits work and is not a fault. The horn is probably a reminder to drivers to push the 'step back' plunger so that the machine can clear the route back out again.

what happens when the step back plunger is pressed?

So stepping back is plunging to let the signalman know your ready to go

AFAIK the plungers were there from the day stepping back began. I dunno when that was.

The plunger lit up a visual in the cabin 'rear cab clear' He could then pull off the starter. I *think* but I am not sure that there was lever in the cabin that actuated the stepping back procedure. Then again as there were plungers on both platforms it may have just lit up the visual. I know the visual was extinguished by the starter returning to danger as the train left. The plunger also lit up a second visual on the headwall to let the relieving motorman know that his back cab was clear. The turn round time was so tight you barely had time to shut down, bang the plunger and walk the length of the other platform to take your next train out. 4 minutes in total.

From what I've seen of both the frame and prints for Elephant Cabin there wasn't a lever which set the procedure up. Were step backs occuring all day? As currently stepping back only applies in the peaks.

The flickering on the Vic line is cause I beleive by somesort of pendulum relay that creates the cyles of the command spots or track circuitis. I'll have to dig out the book and see.

Actually TOK on the Victoria they aren't platform repeaters. They are headwall indicators purely to tell drivers the state of the code. Same difference I know.

A platform repeater cannot show a red aspect, likewise neither can any other REPEATER. What you have on the Victoria Line is 'Headwall Indicators'.

*shrug*

Like I said, you learn something every day. Personally I would have called them co-acting signals, but they clearly aren't at that, so 'platform repeaters' was what fell out of my fingers.

Thanks very much, Met App - you wouldn't happen to know if the VLU will retain them when the new signalling is put in place, do you? The repeaters on the Central Line were taken OOU, but the Vic ones are actually quite useful - same goes for the Jubbly, including the out of use indicators on the stage 1 route.

At Brixton they are technically co-actors. If the route doesn't involve points the corner signal can be the starter, if there are points there is a conventional signal head at normal height as well as the corner signal unit.

As the new signalling system on the Victoria Line will be near enough the same as that on the central, I would presume that the headwall indicators will be removed, as technically they are no longer used as trains do not have guards on them any more.

I know, I was talking generically about platform repeaters and especially in releation to the Central Line

They are now. On the likes of the Central Line, CSA PDs (the new name for SATS) they have to use the Dot Matrix, as when the signal is clear and the countdown to departure is at 10 secs, 'MIND THE DOORS' will flash.

Close! Platform Duties.