IP-based telemetry systems such as iNET require extensive lab testing prior to fielding. Current iNET testbeds typically use several real radios and a mix of pre-recorded and live telemetry traffic. However, stress testing the iNET Radio Access Network (RAN) is hard to perform experimentally because of the limited number of available telemetry radios. To scale up the testing to a larger number of radios, we developed portable, low-cost VM-based telemetry radio simulators that interact with the iNET Link Manager (LM) and real radios to provide additional (emulated) links and queue depth reports. This approach makes it possible to establish the upper limit on the numbers of Test Articles that the LM can handle under various conditions. It also allows for fast reconfiguration of the number and set-up of simulated radios to test out specific use cases. The simulated radios free up real radios for off-site tests while preserving the ability for the continuous testing of LM features until real radios can be reclaimed. The developed testbed is portable owing to its lightweight set-up on the low-cost mac-mini computers. This makes it easy to use simulated radios also in off-site testbeds and field experiments.