yes you can make this work, you have to change excels "interations" by enabling it
On the Tools menu, click Options, and then click the Calculation tab.
Select the Iteration check box.
To set the maximum number of times Microsoft Excel will recalculate, type the number of iterations in the Maximum iterations box. The higher the number of iterations, the more time Excel needs to calculate a worksheet.
To set the maximum amount of change you will accept between calculation results, type the amount in the Maximum change box. The smaller the number, the more accurate the result and the more time Excel needs to calculate a worksheet.
in H7 use the formula =h7&","&d4
this is a circular reference and that is why you have to turn interations on. after doing this, you can continue to change d4 and it will keep adding to h7