I got lucky and managed to get this Huntron Tracker 2000, An old Goldstar 9020A 20MHz Oscilloscope, and a tiny TV from the 60's or 70's for 180 bucks! Of course my focus is on the Huntron since I am a rookie to all this EE stuff and I figured it would help me in my learning (I'm currently in school for EE-first year) and also help me make a bit of money on the side by repair things and reselling them on flea... I mean eBay
Here's my situation and what I want to do. I know it's a tall order, but with you guys here, I feel invincible
First, I need to adjust it so that it's back in tolerance for all the ranges it has. All of them are off. The "LOW" setting is off 5.3% It should be 7.071Vrms and it 6.7 The tolerance in the service manual ±5% so I'm off a bit. I'm not so concerned about that as I am the higher sets, "High" in particular being out by as much as 11% out of tolerance on the low end. Actual reading was 35.9V and it should be 42V.
Now there is another factor involved that could be causing this. The manual says that I need to use a DMM with an input impedance of 10M??, but my rinky-dink Klein MM100 has an input impedance of 1M??. I called myself being smart
and I used a resistance substituter, and set it at 9M?? in an effort to compensate for the different. With that in place, I get a reading of 0
When I connect the DMM to the leads directly, I get the 6.7V mentioned. I'm totally at a loss, but then that's part of the learning curve. I'm sure my calculations could be better.
So my question is, I'm adjusting the variable resistor for the low setting on the board indicated by the manual, and the low to high range is 6.4-6.7 (using the 1M?? DMM), is my measuring set up the problem? Any suggestions on how I can make a testing set up so that I'll be able to test the voltage properly? I have a feeling that the way I'm check for voltage could be the main issue. I'm hoping that it's not a device that needs replacing (they have it well documented on what to check if voltage is not in tolerance). Also I don't have access to a high voltage probe so I can't check the negative voltage which is -1320V.
Any help would be greatly appreciated. I want to get accustomed to working on these and then when I can get the basics down, I want to look into modifying this old unit to use low voltage (3.3V 5V) and also come up with a way to plug it into one of my laptops for further analysis features, possible through and arduino or other single board computer. TIA