Teltone TLS2 Diagnosis and Repair

Hi all, I have a phone line simulator, the teltone tls2. Its from 1987 so its pretty old. I use it to dial into an analog router for in-home dialup. But while using it today it started switching on and off, so I turned it off. But when i turn it back on the right phoneline input (station 29 if anyone knows anything about these) light goes on then the whole thing switches off. If i leave it off i can use it but only for a few minutes

I can smell burnt electronics in that input and the power switch. So I'm thinking a fuse must have blown or something. Since these things are kind of expensive and useful, is there anyway to go about diagnosis of what just went wrong with this? I really don't want to throw it out

Thanks for any help

 

I was looking at how to diagnose the problem for something like this. The board is pretty simple compared to other things. The first obvious thing is the main fuse. Again its from 1987 so who knows the last time the fuse was changed. Its a 1/4 amp 250v/250ma fuse. If changing it doesn't work i'll try a multimeter and find out what capacitor or something went



Trying to find any info on my issue brings me to this thread so i'll update this in case anyone else has this problem