Help with Zenith Console ( long )

[Gelder]

I found the schematics for a 1963 Zenith console but the quality is pretty bad.

First I want to explain my project. I have taken the turntable and the pre-amp tuner/phono out of the cabinet and plan on making them seperates. I am not going to use the amp part. If I get them working I am going to box them in with the wood from the console.

My problem is: I want to hook up power to the preamp to do some testing. I have 3 wires that are blue, brown or black ( it is hard to tell which ) and white.
The chassis is a floating ground so Iwant to hook up a grounded plug to these wires. The problem is I don't know which color is hot and which is neutral. I plan on grounding the chassis to the ground on the plug. Do I also need a fuse? If after getting this far, can I plug it in and do some tests, or do I need outputs hooked up? The turntable is powered by the preamp also, and I plan on using that connection to power the motor. There is also a cable for the input from the arm I need to hook back up.

As you can tell I have never done any restoration projects. This is my first.

I also have some pics, but I don't know how to attach them.

Any help would be appreciated.

( I am going to try and attach some files )

Thanks

[Gelder]

I should have mentioned the model number.

It is the MP500, amp model 9H2OLZ1.

[Thatch_Ear]

Yes, putting a fuse in there is a must do. I am taking it for granted that this has a power supply and wasn't run off the power amp. You need to find which 2 wires run into the primary of the transformer put a fuse on one and have that be your hot wire with the other being neautral.
I have a mono Admiral system that has a preamp/tuner and separate power amp with a separate power supply for the power amp. I just got the caps and resisters to rebuild the amp and PS yesterday.
My advice is to get a Sam's Photofact on the thing which and read the schematic to work the wiring out. The power transformer is probably center tapped to the chassis using the chassis as a common ground. If you plan on using a 3 wire power cord you need to float the earth gound from the chassis ground with a .1 uF 600V cap and a 100 ohm 5 watt resister. Electricity flows from neg to pos so the chassis is the potential and you need a filter to separate it from the earth ground.
First though get the Sam's and read the sticky about vintage tube gear care to find out about reforming the caps, cleaning the pots, etc. Get the tubes checked and replace any weak ones. Chances are there is at least 350 volts and you don't want to make the lights in your neighborhood flicker when you touch something hot.

What is wrong with the amp?

[Gelder]

Sir,

Thanks for the reply. That all made sense... I think. I will look for the Sam's. In fact Tom has already given me the numbers for the one I need.

The main power in went to the amp first, but then had a plug which sent 120V to the preamp. The preamp has it's own transformer. I will use the fuse that was in the amp for the preamp I guess.

The last time I used the system was about a year ago. Other than a scratchy volume pot, some hum, and lots of static noise - it worked.

I want to get into DIY and thought it was a good project to start with and learn something along the way.

Thanks