diff --git a/PDP10/kl10_fe.c b/PDP10/kl10_fe.c
index 142ad235..3acaec22 100644
--- a/PDP10/kl10_fe.c
+++ b/PDP10/kl10_fe.c
@@ -1797,7 +1797,7 @@ t_stat dteo_svc (UNIT *uptr)
     while(not_empty(&cty_out)) {
         char ch = cty_out.buff[cty_out.out_ptr];
         if (ch != 0) {
-            if (sim_putchar(ch) != SCPE_OK) {
+            if (sim_putchar_s(ch) != SCPE_OK) {
                 sim_activate(uptr, 1000);
                 return SCPE_OK;;
             }
diff --git a/PDP10/kx10_cpu.c b/PDP10/kx10_cpu.c
index 02da18f6..13ec3a0a 100644
--- a/PDP10/kx10_cpu.c
+++ b/PDP10/kx10_cpu.c
@@ -4259,7 +4259,7 @@ in_loop:
          }
          /* Handle events during a indirect loop */
          AIO_CHECK_EVENT;                                   /* queue async events */
-         if (sim_interval-- <= 0) {
+         if (--sim_interval <= 0) {
               if ((reason = sim_process_event()) != SCPE_OK) {
                   return reason;
               }
@@ -9049,14 +9049,6 @@ do_byte_setup(int n, int wr, int *pos, int *sz)
                 AB = MB & RMASK;
              }
          }
-#if 0
-         /* Handle events during a indirect loop */
-         if (sim_interval-- <= 0) {
-              if (sim_process_event() != SCPE_OK) {
-                  return -1;
-              }
-         }
-#endif
     };
     /* Update pointer */
     val1 &= PMASK;
diff --git a/PDP10/kx10_tu.c b/PDP10/kx10_tu.c
index 594a7254..68e7a3d2 100644
--- a/PDP10/kx10_tu.c
+++ b/PDP10/kx10_tu.c
@@ -556,7 +556,7 @@ t_stat tu_srv(UNIT * uptr)
                  uptr->DATAPTR = uptr->hwmark-1;
                  uptr->CPOS = cc_max;
                  rhc->buf = 0;
-                 sim_activate(uptr, 100);
+                 sim_activate(uptr, 120);
              }
              return SCPE_OK;
          }
@@ -609,7 +609,7 @@ t_stat tu_srv(UNIT * uptr)
                  uptr->DATAPTR = 0;
                  uptr->CPOS = 0;
                  rhc->buf = 0;
-                 sim_activate(uptr, 100);
+                 sim_activate(uptr, 120);
              }
              return SCPE_OK;
          }
@@ -779,11 +779,11 @@ t_stat tu_srv(UNIT * uptr)
             return SCPE_OK;
          } else {
             tu_tcr[ctlr] &= ~(TC_FCS);
-            sim_activate(uptr, reclen * 50);
+            sim_activate(uptr, reclen * 100);
          }
          return SCPE_OK;
     }
-    sim_activate(uptr, 20);
+    sim_activate(uptr, 50);
     return SCPE_OK;
 }