Model 2556-ALN Phase Locked Oscillator

Designed to replace the crystal oscillator LO chain in a DB6NT 10GHz Transverter unit or your own Transverter design, the Model 2556-ALN will provide superior low noise performance almost equaling the Phase Noise performance of a crystal oscillator multiplier chain.

Now there is an alternative to the unstable crystal oscillator chain that drifts constantly. The Model 2556-ALN allows precise receiver/transmitter frequency control using a stable external 10 MHz or 100 MHz reference oscillator like a TCXO, Oven Controlled Oscillator or a Rubidium Oscillator. The Model 2556-ALN may used to replace any Local Oscillator chain by providing an external X4 multiplier ahead of any 10GHz mixer assembly. Interface to a DB6NT 10GHz Transverter would be through the last X4 multiplier stage. This application note shows how easy it is to implement. (Caution - an 10 to 12 dB attenuator will be required to interface to your DB6NT Transverter.)

The Model 2556-ALN outputs a single ultra low noise 2556 MHz signal. With a minimum of +17 dBm of output power, the oscillator is perfect for driving 3-dB power spliiters, multipliers and power amplifier stages. The ultra low noise performance of the Model 2556-ALN begins to approach crystal oscillator phase noise performance. This allows the unit to be used for such things as EME communications, long-haul low noise communications and digital operations like JT65 and similar modes. With both end of a communications link using a Model 2556-ALN, both stations will be absolutly on the same frequency when locked to a 10 MHz GPS disiplined oscillator reference. No more hunting around the dial for the other operator.


  • 13.5 Vdc @ 140ma typical, designed for battery/remote operations
  • 10 MHz or 100 MHz Reference Frequency input
  • +17 dBm RF output minimum, (+18dBm typical)
  • 2nd harmonic is > -20dBc below fundamental
  • Phase Noise -90 dBc/Hz @ 1KHz typical
  • Phase Noise -115 dBc/Hz @ 10KHz typical
  • Phase Noise -126 dBc/Hz @ 100KHz typical
  • Reference Spurs > -150 dBc
  • Operating Temperature Range -20 Deg C to +80 Deg C
  • External Lock Signal output provided
  • Small size - 3.75" Long x 1.75" wide x 0.89" high
  • Full 1 Year limited warranty
  • Link to ->On-line Model 2556-ALN Manual

    Link to -> Model 2556-ALN Phase Noise Measurement Plot