RA intermittent fault
Maybe releted.
I've been flying the bird for about 7000hrs (4000 NG). I've never had a problem like this until last month. Than I had the same issue they experinced(It was a -700 ). Doing a Visual APP manually, I've noticed there is no automated alt callout at 500'. Felt strange. By the time I looked in the RA reading was normal. But then there was no 50' 40' 30' 20' 10' callout ( option on our planes) either and the left RA was showing -7'. On the way back to base everything was normal. Maintanance checked if there is any recorded fault but there were none. Flying the same ship later to other DEST no probs. Two weeks later same ship, same DEST and it happened again. Maintanance answer: No recorded fault, system works normally.
Tought might be interesting to see if any other NG drivers had this before.