How to demonstrate signal reconstruction using impulse train

I wish to demonstrate signal reconstruction steps from recieving a 'continuous' signal to reconstructing it to a filtered digital signal.

My issue is with the impulse train I'm using to sample the 'continuous'input signal. Since we know all signals are discrete to simulate a 'continuous' signal I use a large sample rate (t=0:1/10000:0.01). Then I create an impulse train using Imp= zeros (size (t)). This means that they are using the same time scale. When it comes to varying the frequency of the impulse train (I.e changing the sample rate ) by changing f in imp (1:f:end) =1 You can really only show values of f from 2 to 10 then after that the signal doesn't get sampled much at all. Is this normal? It doesn't give me much to demonstrate. Also at a value of f=2 the most samples I can get before 1. The signal doesn't fully reconstruct. It looks delayed a little. Is this normal?