Search results

This is a dumb terminal that was popular in the 1970's and is now considered a collectors item. It has the classic beige/brown "clam shell" design popular with many models made by Lear Siegler during that era of glass tele-types. This particular terminal came into my possession in a...

Hello, I am desperately hoping someone here can help me find a Maintenance manual or schematic on the Lear Siegler ADM-31 dumb terminal. My friend and I are trying to diagnose a problem with this terminal and a technical schematic would greatly help us in tracing the signals. I have searched...

JonB, maybe you're referring to the wrong cap because, to me, C76 is a non-polarized ceramic cap; not a tantalum. The ones along the sides (like C75) appear to be tantalum solid axial bullet caps, as Frank said. I tested each of them with my DMM in continuity mode on both the GND and +5 rail...

I have a circuit diagram for the smps and monitor but not for the main pcb. There may be one somewhere but not on the internet. From the attached pic, could you point out what the tantalums look like? The ones beside most of the ICs are ceramic caps, correct?

I'm repairing a Lear Siegler ADM-31 dumb terminal. I pulled out the oscillator to test it and the frequency read around 6.0 Mhz but the reading is 19.584 Mhz. Also when trying to remove the oscillator from the PCB, I broke off two of the legs, so I'm in need of a replacement. I tried googling...

Hi, I’m repairing a Lear Seigler ADM-31 dumb terminal and I suspect the flyback transformer is faulty. Not getting any high voltage off the anode. Does anyone know where I can get a replacement flyback transformer for the ADM terminals? It has a Samsung monitor 12DN4KA and all the flyback...

Here's a picture of the original Filter cap and the replacement I bought from Digi-Key. The original is a 16uf 63V B.P. cap. I could not find an exact match so went with the closest which was a 10uf 63V B.P. but as you can see from the pic it's a LOT smaller. This has got me thinking that...

Hi there, I'm trying to fix a Lear Siegler ADM-31 dumb terminal I purchased on Kijiji and I'm hoping to get some guidance on this forum as to how to proceed next. When I initially powered it on, it beeped once before I heard a "pop" and then a little puff of smoke coming out from the back...

I recently acquired a 486 computer which I'm trying to build into a DOS Gaming Station. It's a full-sized Single Board Computer on a Transformer Backplane. Ideally, I would like to install an 8GB HD but the BIOS is limited to 512MB HD. Before going the route of DDO's or CF2IDE or controller...