I am looking for anyone familiar with the K19 Intercom box produced by Melco Labs in the early 80's. I have the installation instructions. My customer is using this as a campground intercom, and it has developed a ground hum that is rendering it useless. They are using it as a stand-alone intercom with modified 2500 and 500 sets. If anyone is familiar, drop me a line and I'll explain the problem in detail.

Thanks!