Never been on a 156 though they look similar to 158's 153's (155's) and 150's. I expect they are closer to a 158? I used to see them come down to Cardiff Central on Central Trains services. We worked 150/2's but once due to shortages we borrowed a Central Trains 150/1, and a few times I got to work it. I remember the first time working it (As we were told they were the same as 150/2's to work except they had a slam door crew door, the rest were the usual power operated doors. I stood there having closed the other doors looking for the crew door switch. Where was it?

About 10-20 seconds later I realized my obvious mistake!
When I realized my mistake, I soon got the hang of them, but I did realize, as it was possible to stand on the platform while giving the driver the signal to go, one had to watch one didn't get into the habit of doing that. While I soon caught on, other guards didn't and I heard of a couple of guards who were not used to this who found themselves left behind on the platform! Easily done on a 150/1 when one has spent years working 150/2's! Once used to a 150/1, because one can close a manual door even quicker than a power operated door, it did actually speed up platform time when used to them. It was about getting oneself into a safe working routine.
My favourite of all the units to work was the 143 every time. Nothing as good as a 143 to work. They always made me smile!
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