You can build a very versatile square wave oscillator use a 555-timer IC. I would highly recommend that you use a CMOS part such as LMC555, TLC555, ICM7555.
You can also build a simple oscillator with a Schmitt trigger inverter.
Which Beck circuit; there are several. Please post your schematic. If it does not already have reference designators for each component, be sure to add them.
When considering the requirements of a "Building-Block" Circuit,
all of the Inputs and Outputs need to be specified,
or at least a good explanation of what the end-result should be
when incorporated into other described Circuits.
All these questions need to be specified, ( and maybe more ) ..........
What is the purpose of this Oscillator ?
How much Voltage-Output ( Source & Sink ) ?
How much Current-Output ( Source & Sink ) ?
Will the Load be Capacitive or Inductive ?, ( what is the "character" of the Load ) ?
Total Frequency-Range ( from-to ) ?
Does it need to be adjustable ?, ( Frequency, Voltage, Duty-Cycle ) ?
Is the Duty-Cycle required to be precisely 50% ?
What will supply Power to it ?, ( also Single-Supply vs Dual-Polarity-Supply ) ?
Do the switching-edges need to be sharp or soft, and why ?
Frequency-Stability vs Temperature or Load ?
Does it need a Start-Stop Input ?
When stopped, does the Output need to be High, Low, or High-Impedance ?
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