Setting up a SCS DR 7400 as a hardware pactor modem with the FLEX-6000

Content provided by: Rodney, KG5DWX

The following information can be used to connect and setup a DR-7400 P4dragon PACTOR 4 Modem with any FLEX-6000 Signature Series SDR.

Physical Connection:

Connect the DR-7400 to the ACC connector on the FLEX-6000 using a  Farallon 9087 cable.  It can be purchased via this link:

SmartSDR Setup:

The slice receiver used for PACTOR must be in DIGU or DIGL with a RX filter wider than 3kHz. This will enable the lower latency receive filters to decrease turnaround time.

2. Make sure the audio levels are set properly. The MIC level meter should peak right under 0.

3. Although you can use AGC with PACTOR on some paths you can save a few milliseconds of latency by setting the AGC to OFF and properly adjusting the AGC-T to match band conditions.

Summary of my SmartSDR settings:

PROC=off (Default on DIGIU)
DEXP=off (Default on DIGIU)
Set Comport you are using to Active in CAT


RMS Express Setup:

The following settings were used for configuring RMS Express

RMS Express:
TNC setup:
PSK=4000 (max)
FSK=4000 (max)
TX delay 0 to 20
Radio - Flex

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