What is THIS ? ( on Wireless trigger)

[pentaxpete]

I got a 'Yongnuo CTR-301P' wireless flash trigger after reading about it on here -- I got it to work with my Bowens Studio flash and smaller units but there is something on the bottom of the 'Receiver' that has NO mention in the Instructions -- a VERY SMALL switch set marked 'ON KE' and underneath ' 1 and 2' ( next to the tripod hole ) - Do you know WHAT this is please and should I set it to 'on' ?
Also -- there was a CR2 Battery included but there seems to be a battery in the Transmitter as well -- one I have never heard of a '23A' battery -- when it fails where do I get replacements ?

 

[kendo1]

I think that is the channel switch- 4 available.
From 2.10:

The battery needed is a CR2. I've no idea what the 23A is, though there is a 2/3A and a 123A...
Check battery types on Wiki.

 

[pentaxpete]

Really HELPFUL !! I'm a You Tube Newbie so I never thought to hunt in there !

 

[bdslr]

Hi Pete,

I have a set of those triggers - and my battery recently ran out in the transmitter. It happened when the transmitter was squashed in my kit bag which kept the button pressed down.

I got two for £2.49 from the bay http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=400697772033

One is now in the trasmitter - the other in my kit bag.

Hope that helps!