Distribution Amplifiers

Model Overview (click on the brochures tab above, for a full list of brochures):

• DA101010 Series: Low Cost, 100 kHz to 15 MHz with up to 13 outputs
• DA1-100 Series: Ultra Low Phase Noise, 1 - 150 MHz with up to 20 outputs
• DA1-150 Series: Ultra Low Phase Noise, 1 - 200 MHz with up to 15 outputs.  RS232 & Ethernet interfaces.
• DPA Series: Low Cost Pulse / Square-wave Models, DC - 10 MHz with up to 20 outputs
• PTS50 Series: Low Cost, 100 kHz to 15 MHz with up to 7 outputs.
• TT Series: Pulse / Square-wave Models, DC - 10 MHz with 16 outputs.  Outputs aligned to < 150 ps.

Key Features include:

• MTBF of over 500000 hours. Three year warranty on most distribution amplifiers.
• Units available in standard frequencies of 1 pps, 100 kHz, 5 MHz, 10 MHz, 15 MHz. Wideband models (1 MHz to 150 MHz) also available.
• AGC controlled. Output level remains constant even if input level varies. Removes any AM noise from the input.
• Five to thirty isolated outputs.
• Sinewave or Squarewave Outputs.
• Independent adjustment of each output level on most models.
• BNC, TNC or SMA connectors available.
• Pure 10 MHz output. Harmonics are -70 dBc (-25 dBc on some models).
• Switchable squarewave outputs from 10 MHz, 5 MHz, 2 MHz, 1 MHz, 100 kHz and 1 Hz (PTS50 and DA101010).
• Units can be interconnected for up to > 1000 outputs.
• Very Low Phase Noise.
• Option to have any or all connectors isolated from earth.
• Alarm relay output option.
• Backup internal 10 MHz option (not available on all models).
• 2nd or 3rd input with automatic switchover.
• Redundancy Option (not available on all models).
• Power Operates from 100 - 240 VAC (usable 90 - 260 VAC) supply or optional external 12 V DC supply.

What to look for in a Frequency Distribution System:

The important things to look for in a distribution amplifier are:

• Gain: It's important that the amplifier doesn't just have 0 dB gain, but rather a figure of at least 5 dB. This allows the output of the frequency reference to be increased to the desired level. Also see AGC.
• AGC (automatic gain control): As already mentioned, some gain is needed in an amplifier. On top of this, some type of AGC should be incorporated. An amplifier with AGC has a fixed output level even if the input level varies by a few dB. Amplifiers with 0 dB gain will have fluctuating outputs should the input level vary. This will have an impact on timing issues.
• Variable output levels: Again, amplifiers with 0 dB gain don't allow the output levels to be individually optimized. Most of our distribution amplifiers allow every output to be set to a different output level. This is important to optimize for different cable lengths and for the different types of equipment to be connected to the amplifier.
• Phase Noise: Phase noise is often overlooked but is a very important parameter of a frequency distribution system. Unless the distribution amplifier has low phase noise it will impair the quality of the frequency reference. Our DA1-100-10 series have some of the lowest phase noise specifications available in today's market. Phase noise of < 130 dBc/Hz at a 1 Hz offset and floor noise of -170 dBc is available from Precision Test Systems on their high performance amplifier range.
• Channel and Reverse Isolation: It's important that the reference frequency standard connected to the frequency distribution system is protected against noise, shorts and poor VSWR's of the equipment that may be connected to the system. Channel isolation should be at least 40 dB for a standard amplifier and 90 dB for a high performance amplifier. Reverse isolation should be at least 90 dB and ideally better than 125 dB to make sure the reference is well protected.