At least from 1823 to 1828, there was a Seconde-Lieutenant Schalenkamp in the 17. Landwehr-Regiment.
In the army lists of 1823, 1824 and 1828, he is listed with the cavalry.
On 13 October 1827, he changed (back) from the infantry of his regiment to the cavalry:
Probably, he is identical with a Sekonde-Lieutenant Schalenkamp in the list of officers of the Clevisches Landwehr-Kavallerie-Regiment of 2 September 1814. This regiment was used to form the 1. Rheinisches Landwehr-Kavallerie-Regiment in 1815.
This doesn't explain the number "34" though.