These waveguide bandwidth harmonic mixers are designed for use with spectrum analzyers with diplexers, such as the Tektronix 492 and 494 and the Hewlett-Packard 8555A, 8565A and 8569A. They are also used as phase locking and receiver mixers for antenna measurement systems such as the Scientific Atlanta wide range receivers. When used with an external diplexer*, these harmonic mixers can be used to phase lock millimeter wave sources.
The mixer contains a rugged stripline mounted silicon beam-lead Schottky barrier diode (Models FM and DM use a GaAs diode). The small physical dimensions of these mixers make them ideal for use in lightweight, compact equipment. Two diode, balanced harmonic mixers optimized for even or odd harmonic mixing are also available. Consult factory.
*LO/IF diplexers are available for IF & LO ranges shown below:
Diplexer model # IF range LO range Diplexer Outline Drawing
MD1A DC-1 GHz 1.8-7.5 GHz
MD2A DC-1 GHz 5-20 GHz
MD4A DC-2.5 GHz 5-20 GHz
**Minimum detectable signal measured with Tektronix 492 or 494 Spectrum Analyzer
LO and IF frequencies to 18 GHz
LO power requirement +15 dBm maximum, +6 dBm typical
Total RF + LO power input 100 milliwatts maximum
Bias requirements: See application note MIXER DIPLEXER AND DIODE BIAS. Typically operates self biased with DC return to ground.
For recommended self bias circuit for models FM and DM, see application note SELF BIAS CIRCUIT FOR GaAs DIODE MIXERS.