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Article ID: 000042547
Last Modified Date: 12/10/2021
Access Level: Public

HDX - Trouble connecting though Secure Systems Group Dial Isolator.

An issue where a ViewStation Owner had replaced a ViewStation V.35 with an HDX has been resolved . The new serial connection path was HDX > RS-530 > Secure Systems Group Dial Isolator > RS-530 > Adtran ISU 512. Also attached to the Dial Isolator was a Titan 3014-2 KIV7. The Dial Isolator acts as an A/B switch to select between secure and non-secure calls.
Note:  There is not a lot known about the Secure Systems Group Dial Isolator as it is no longer manufactured and the company has since been sold to Cryptek ( Documentation is difficult to obtain.
The HDX is not a direct drop and insert replacement for a ViewStation V.35 in this configuration. There are differences in the way the HDX handles serial interface signaling than that of ViewStation Products.
To configure the HDX for this implementation, you must set the following:
System > Network > V.35/RS-449/RS-530 >Page 1 of 5
Enable V.35/RS-449/RS-530 = checked on

V.35 Ports Used = 1 (for single channel bonded calls)

Area Code = your area code

Port 1 = Your local dialing number (LDN)
Page 2 of 5

For Adtran ISU-512, you can select the Calling Profile predefined or select Custom and define appropriate prefixes to be passed to the Adtran to dial the appropriate speeds (see Adtran documentation for more information)

Page 3 of 5
All Signaling Leads will be set to Normal except:
CTS = Ignore
Answer on DSR = checked on
DTR Pulse Duration (secs): left at 3 (default)
Trigger call on H.320 Data = checked off

Page 4 of 5
Crypto Resync = checked off
Use RTS Signal for Resync Pulse = checked off
All other settings left at default.

Page 5 of 5

Broadcast Mode is not applicable. Leave all settings at default
Adtran Configuration information
HDX Configuration:
Navigate to: System >> Admin Settings >> Network >> V.35/RS-449/RS-530
On the Configuration page (1of 5), configure the following:
Enable V.35/RS-449/RS-530 = yes
V.35 Ports Used = 1
RS-366 Dialing = Checked Area Code Port 1 = (DID) Primary Incoming Directory Number
On the Call Profile page (2 of 5), configure the following:
Prefix = NONE
Calling Profile: Adtran_ISU512 (or Custom)
If Custom, configure the following Suffixes: Adtran Suffixes are #C#R. C=call type (56k or 64k) R=call rate or number of B channels used)Speed Prefix Suffix112k #3#2128k #4#2224k #3#4256k #4#4336k #3#6384k #4#6448k #3#8 512k #4#8
On the Signaling page (3 of 5), configure the following:
ALL Leads left at default of "Normal"
Answer on DSR = Unchecked
Delayed DCD Hangup = Unchecked
DTR Pulse Duration (secs) = 3 - default
Trigger Call on H.320 Data = Unchecked
On the Crypto Resync page (4 of 5), leave as default unless configuring to use with an encryption device
On the Broadcast Mode page (5 of 5), leave as default unless configuring to use for H.331 broadcast transmissions.
Adtran ISU 512 Configuration:
Settings which need to be configured on the Adtran ISU-512. Any settings not mentioned are assumed to be left as <default>
Navigate to 3=CONFIG > 1=Netw.options > 1=Dial Line > 1=Switch type = Configure per ISDN service configuration 2=Call type = 4=Data 64Kbps 3=Terminal ID = Configure per ISDN service configuration - SPIDs and LDNs 4=Dial options = 2=RS-366 5=Auto Answer = 2=Enabled 6=Connect Timeout = 2=30sec (default) 7=Call Screening = 1=Answer Any 0=Call NumID = 2=DisabledNavigate to 3=CONFIG > 2=DTE(V.35) options > 1=Max Bit Rate 1=64k Mode 1 = Configure the Maximum number of channels in use (8=8x64k for 512k / 4 ISDN BRIs)2=Connector Type = 1=RS-530 3=530-V35 Cable = 2=Disable ** 4=RS366-Y Cable = 2=Disable ** 5=CTS Options = 3=Follow CD 6=CD Options = 2=Normal 7=DTR Options = 2=Idle when Off 8=DSR Options = 1=DSR Forced On
Note 530-V35 Cable and RS366-YCable is disabled unless Adtran Proprietary cables are in use.
This is not typical in a Polycom Connected implementation unless a dial isolator and/or encryption device is used. This would also be used when connecting in Dual Port Mode, which requires the Adtran Proprietary cables.
DO NOT USE "QUICK SETUP". This is found under 3=Config > 4=Quick Setup. Using quick setup will OVERRIDE these recommended settings with a default setup. This will change your stored values.
The status lights on the front panel of the ISU-512 indicate the following:
RS = Request to Send
CS = Clear to Send
TD = Transmit Data
RD = Receive Data
CD = Carrier Detect
TR = Terminal Ready
SR = Data Set Ready
Physical Connection:
The cabling used for this configuration is the following:
HD-68 M to "Y" DB25 M RS-530/RS366 Serial Cable (P/N 2457-21263-001)
The connection path for this configuration is the following:
HDX V.35/RS-449/RS-530 Network Port 1 > to HD-68 M to "Y" DB25 M RS-530/RS366 Serial Cable (P/N 2457-21263-001) > to RS-530 Male connects to ISU-512 RS-530 Port DB25 RS-366 Male connects to ISU-512 RS-366
Dialing PortReferences:
  • See the Integrator's Reference Manual for the HDX Series for more information on cable pinouts.
  • See the Administrator's Guide for the HDX Series for more information on system configuration settings.
  • See the Adtran ISU-512 User Manual for more information on Adtran configuration.
1.0.2, 2.0.x