DIY active EMI probe/magnometer closed loop, along with xformer questions

[rwgast_lowlevellogicdesin]

So I have an hmc5883 x,y,z compass or manometer I planned to put in my robot. I havent gotten time to implement it in my robot yet, I have sonar, bump, wheel encoders, and am currently making a homemade 360 degree laser scanner. The Accelormeter/Gyro and magnetometer were going to be the last dead reckoning tools implemented. I haven't done a lot of reading on the HMC3885 but I know its common and has library written on almost all micros so its easy to implement.

Right now I am working a a Magnetically regulated PSU, the trans former as two taps one for regular 15v output and the other that has 440v output the 440v tap drive a tank circuit to keep the core from fluctuating to much under load.  I plan on using this thing to do some electroplating, specifically making nickel acetate. I know thes kind of transformers put out a lot of magnetic noise, and I had planned on sheilding it with aluminium tape, because I also want to try adding a digitally controlled precision rail that  has 1mv resolution and current limiting along with a 1- 10amp current source that maybe has 10-20ma steps (not sure if im over optimistic about that lol). So basically I want to be able to PWM the primary tap along with the output tap after the rectifier to make a closed loop system to get the least amount of noise possible, I have a feiling I will need pwm along with filters not just some sheilding.

So basically I also have this guy https://www.parallax.com/product/605-00005 I was hopint I could somehow build a nice magnetic probe gor my scope, while using the compass in the psu for the control loop. I have made a few cheap passive 500hm EMI probes I found  directions for in other threads, but im not sure if what im trying t do is even close to realistic? If so maybe someone know a good recource to get me started at least on the probe?

[rwgast_lowlevellogicdesin]

Kind off topic but I asked about the parts on hand becuase I have to work with what I have! I am flat broke right now, my unemployment just ran out  and im trying to transition from a sparky to a hardware guy. I have a consultation gig repairing welding machines but I haven't gotten any money out of that quite yet. Im a single dad staying with my folks at the moment after what happened between my ex gf (baby mama) and I. For some reason my dad wont let me install a 40/50 amp 240vac connection in the garage so im re wrapping a huge microwave transformer to output 220/240vac @ 40 amps. I would also like to build a few isolation transformers, small and big, but I cant find alot of infor on my idea of a small isolation transformer... would using a toridal freight out of a PC psu and wrapping it equal time on both sides work? I know you need equal wraps and that wire size matters effect how much current you can pass. But what I dont know is how much current a toriadal likt that would handel and the difference between using 2 passes on each side vs 10 passes. :/ I have a really nice transformer theory book but it is in my storage which is currently locked becuase I cant pay the bill ATM. Also if you want to wrap triflar transformers for a diode ring will psu torriods work or are the the wrong perinyability?