User contributions for Mark999

18:2118:21, 27 March 2025 diff hist +238‎ Pushbutton switches ‎ centralab switch pin dimensions

15:4215:42, 23 March 2025 diff hist +136‎ m 7L5/Repairs ‎ studs are plastic current

17:1917:19, 22 March 2025 diff hist +794‎ 7L5/Repairs ‎ input repair
17:1617:16, 22 March 2025 diff hist 0‎ N File:A2000A2 reassembled.jpg ‎No edit summary current
16:5116:51, 22 March 2025 diff hist +62‎ N File:A2000A2A2 B side decoupling.jpg ‎ View of the resistor after desoldering A2000A2A1 current
16:5016:50, 22 March 2025 diff hist +71‎ N File:Toasty resistor sandwich A2000A2.jpg ‎ Overheated 4.7Ω resistor for B1 (+15V rail) on A2000A2A2 current

22:3122:31, 21 March 2025 diff hist +966‎ N L3/Repairs ‎ Created page with "Symptom: scope would not power on with 7L5 (+L3) installed. A slight smoke smell was present. Checking resistance between power rails indicated a short between +15V and ground. Eventually I noticed a discolored resistor connected to the edge connector for the L3. I disassembled the L3. Even though I used the proper size pozidrive screwdriver, two screw heads stripped before they loosened, and another screw sheared off. I resorted to drilling these screws out with a 1/16..." current
22:2922:29, 21 March 2025 diff hist +151‎ m File:L3 A125 atten cap replaced.jpg ‎No edit summary current
22:2722:27, 21 March 2025 diff hist +110‎ N File:L3 A125 atten cap replaced.jpg ‎ This orange cap on the A125 attenuator board was the cause of the short between +15V and ground.
22:2622:26, 21 March 2025 diff hist +232‎ N File:L3 screws galling.jpg ‎ Screws holding L3 motherboard in seemed overtorqued and brittle. The heads of two basically disintegrated when I tried loosening them with a pozidrive screwdriver. Another sheared off. Note galling on the intact screw. current
21:4921:49, 21 March 2025 diff hist +236‎ L3 ‎ add photos current
21:3921:39, 21 March 2025 diff hist +1‎ m File:L3 mother input.jpg ‎No edit summary current
21:3721:37, 21 March 2025 diff hist +187‎ N File:L3 mother input.jpg ‎ 7L5 L3 motherboard input section detail K62 selects the termination resistance; one of its legs exits the spacers and is soldered to the pin that the input BNC connects to.
21:3321:33, 21 March 2025 diff hist +61‎ N File:L3 mother comp side.jpg ‎ 7L5 L3 input module motherboard, component side current
21:2121:21, 21 March 2025 diff hist +59‎ N File:L3 bottom.jpg ‎ 7L5 L3 input module with bottom cover removed current
21:1121:11, 21 March 2025 diff hist +56‎ N File:L3 top.jpg ‎ 7L5 L3 input module with top cover removed current

21:5121:51, 18 March 2025 diff hist +113‎ Miniature relays ‎ add L3 current

23:5723:57, 3 March 2024 diff hist +174‎ R7912 ‎ add pulsed laser app note 47N1.1
23:4923:49, 3 March 2024 diff hist +12‎ m RJ45 connector ‎ add awg610
23:4023:40, 3 March 2024 diff hist +28‎ m AWG2005 ‎ gpib current

23:1923:19, 22 February 2024 diff hist +27‎ m 7912AD ‎ adding to 'manual needed' category since we only have partials
23:0923:09, 22 February 2024 diff hist +110‎ N File:062-2909-00.pdf ‎ Datasheet describing a Self Test Adapter for 4051/4081, part numbers 013-0173-00 and 013-0173-01