Sony DSC-F1 Video Connector?

What's the connector for the DSC-F1 Video Out?
If I stuff in a 1/8" phone plug, I get video out.
Problem is that it's about 3/16" from being plugged
in all the way. I pushed as hard as I dared.
Seems to be bottomed out.

Since it's not latched in, I have to hold side
pressure on the connector to keep contact.

So, do they use a proprietary connector? Or am
I just too timid to push it in?

Second question.
There's a square hole on the bottom next to the reset
swtich. The manual calls it a "battery adapter attaching part".
Since my battery ain't too good, that sounds like something useful.
What can you tell me about this port and things that hook into it?

Thanks, mike
My return address is good, don't change it.
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