Old Grundig VS 190 Camcorder REC Problem

Hello, I have a Grundig VS90 camcorder and I have a problem, I can't see what my lens sees, it shows me a blue image. I took a blank tape to see if it could read it, and it did read it. I recorded on the tape and it recorded, but the problem is that it only recorded black (I removed the cover for those who thought I hadn’t done that ^^). It's a device from the '90s, help me!!

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