Build with just KLH10.

.github/workflows/build.yml

@@ -14,7 +14,8 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-22.04]
-        emulator: [simh, klh10, pdp10-ka, pdp10-kl, pdp10-ks]
+        #emulator: [simh, klh10, pdp10-ka, pdp10-kl, pdp10-ks]
+        emulator: [klh10]
     steps:
       - uses: actions/checkout@v2
       - name: Install dependencies
@@ -23,7 +24,7 @@ jobs:
         if: ${{runner.os == 'Linux'}}
         run: sh -ex build/dependencies.sh install_linux
       - name: Build
-        run: make check-dirs all EMULATOR=${{matrix.emulator}}
+        run: make check-dirs all EMULATOR=${{matrix.emulator}} MCHN=LC
       - name: Deploy
         if: github.ref == 'refs/heads/master'
         env: