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Azur Electronics

The HP 3730B Down Converter is used with plug-in RF Modules to provide RF to IF conversion to either 70MHz or 140MHz. A tracking AFC and recovered sweep facility causes the local oscillator in the 3730B to track the incomming swept RF signal. Option 010 incorporates an additional IF section comprising a 25dB fixed gain amplifier and a 30dB stepped attenuator (switched in -5dB, +5dB, +15dB and +25dB steps). Minimum input level is normally -15dBm and with Option 010, -40dBm. The 3730B cost $4,350 in 1987.

Front Panel with optional IF Input & Output,
controls and space for plug-in RF Module
RF Modules
3736B 1.7 to 4.2GHz $5,600
3737B 3.7 to 8.5GHz $6,700
3738B 5.9 to 11.7GHz $7,800
 3739B   10.7 to 14.5GHz   $11,150  
Rear Panel with Sweep In and Sweep Out BNC connectors
Top and bottom views with the covers removed
April 2009

This 3730B includes the Option 010. I have not been able to find a Manual for download. Apart from a good clean up, it was in good condition.

June 2009

Powered up ok and all the voltages are correct. Without the plug-in RF Module, it is of limited use. The regulated power supply provides +20V, +15V, +5V and -5V. The IF input and output can be used independantly of the RF Module. This provides a useful IF amplifier and attenuator which is flat to the 600MHz -3dB point then tails off smoothly.

February 2010 

Now sold.