IBM 6151 Maintenance And Service Manual page 124

B7x
RT PC Modem Cable - R8232C (16 Pin)
Additional Tests: Run the RT PC Multiprotocol Adapter
Checkout.
Removal Procedure: See Adapter Removal in Section 4.
Repair Checkout: Run the RT PC Multiprotocol Adapter
Checkout.
B8x
RT PC Automatic Calling Unit Cable - R8366
Additional Tests: Run the RT PC Multiprotocol Adapter
Checkout.
Removal Procedure: See Adapter Removal in Section 4.
Repair Checkout: Run the RT PC Multiprotocol Adapter
Checkout.
B9x
RT PC Modem Cable - X.21
Additional Tests: Run the RT PC Multiprotocol Adapter
Checkout.
Removal Procedure: See Adapter Removal in Section 4.
Repair Checkout: Run the RT PC Multiprotocol Adapter
Checkout.
3-0020-46 Service Manual