National company HRO 500 receiver HF oscillator extremely microphonic on FM mode test SDR receiver

Pull out the sweep transistor.
Set the VFO to 9 Mhz or so.
Listen on and RTL-SDR with CubicSDR software.
Narrow Band FM.
HEAR all the NOISE when you bang the radio around with just a little plastic straw?
So no wonder iit will not hold Synch lock.