| Number | Date | Country | Kind |
|---|---|---|---|
| MR 5332 | Jul 1981 | DEX |
| Number | Name | Date | Kind |
|---|---|---|---|
| D179132 | Forrest | Nov 1956 | |
| D193895 | Fischer | Oct 1962 | |
| D203824 | Rawson | Feb 1966 | |
| D227594 | Beck | Jul 1973 | |
| D239006 | Kelley | Mar 1976 | |
| D266153 | Suslov | Sep 1982 |
| Entry |
|---|
| Telephony-1/30/78-p. 19-Electrical Test Equip. at top. |