10 week scan piks & HB?

Ky
I'm going for Harmony test (privately in UK) this Thursday (25/5/17) I'll be 10+4, had viability scan done at 7+1 which was a blob with a pulsating HB. I'm wondering what to expect, how clear will babies silhouette be & what kind of range were your little'uns HB's around this time? 
I've never got this far with previous pregnancies so really don't know what to expect. I'll be going on my own as well so would like to be confident in what I should be seeing (within reason). 
Any piks people are happy to share & info on HB's would be hugely appreciated 😊
Thanks ladies x