Help getting Tracker Fixed
Posted 04 January 2013 - 03:34 PM
Or does anybody here fix them reasonably? I'm on Disability and things are kind of tight right now, waiting for my next surgery from getting run over by a car!
I've got a great old Sandcast C8 that is fantastic and looks like the day it was made...
Posted 04 January 2013 - 03:55 PM
Posted 04 January 2013 - 04:16 PM
now it's ka-put
Posted 04 January 2013 - 06:26 PM
Posted 04 January 2013 - 06:38 PM
Mine would look like Curley (Jerome) Howard (The 3 Stooges)
and let the smoke out of my tracker as he tripped over it
Posted 04 January 2013 - 08:18 PM
Rather than just plugging it in and switch it on when it's been sitting a long time unused, you plug it into a variac transformer and slowly bring up the voltage over a day or so to Rejuvinate the capacitors. But some wont form correctly coz they are too dried out and old and blow anyhow. The usual procedure is to replace all the electrolytic capacitors, check for burnt or open resistors and check the transistors and that fixes 90% of the usual problems with such things.
Your smoke came from the Main unit, not the hand controller right?
Posted 04 January 2013 - 10:40 PM
I pulled the covers off mine and took a look, I would think it should cost less than $20 dollars in parts to fix it, maybe $25 ish if both the power transistors are blown.
The hand controller has a 12v adjustable oscillator made from small signal transistors and ought to be just fine. It pulses 12v through the two power transistors into a transformer that steps it up to near line voltage to drive the motor. I can fix it if no one is closer to you as I'm an electronics tech if you want.
If you have a small phillips screwdriver, unplug the power cord from the wall and pull the main box's lid to see if you can see one of the 3 grey electrolytic capacitors bulged or leaking and if one or more of the three black rectifier diodes have burned.
Hopefully the orangeish large power resistor next to and below the diodes is unburnt as it goes to the power transistors. Also, check the handbox plug to make sure a wire isnt loose or shorted at the plug. the plug cap unscrews if you want to check it but be gentle, dont force it if it's stuck. Has the fuse blown or is it intact?
Posted 05 January 2013 - 11:24 AM
What I have found is about 90% of the time on these type of drive correctors is that one of the power transistors has gone bad and is now shorted to ground. This causes all the current to be dumped into the secondary of the transformer, which causes things to heat up and then let the smoke out.
The other common problem is that a wire breaks in the hand controller. The hand controller contains parts which form the oscillating circuit. If the circuit doesn't oscillate what happens is one power transistor is turn on all the time and again all the current is now flowing thru the secondary of the transformer and things get hot.
As Dgreyson sugguests pull the cover off and see what looks damaged and if you can post some pictures I'm sure that we can get a good idea of what went wrong and how to repair it.
All the Best,
Posted 05 January 2013 - 01:25 PM
Posted 05 January 2013 - 01:38 PM
I admit I dont know a resistor from a Flux-Capacitor!
I am recovering from my 6th surgery after getting hit by a car, then getting Staff infection,and a Hear attack after a surgery and I threw a blood clot. I thought it would be a good time to have it looked at. I'll try and dig it out.
BTW dont laugh about the Dynamax, it has superb optics!
Posted 05 January 2013 - 02:54 PM
If it isn't working off the battery then it the odds are low that it will work off the 110 VAC house current since all the rectifier circuit does is take the 110AC and make 12 volt DC, just like the battery is providing. When you hook it up to the battery the rectifier section is out of the circuit.
Anybody got a schematic ? The guys at Criterion were pretty smart and they also got many of their ideas from the literature of the day so I bet the circuit is pretty close to the Saxon circuit publish in Jan 1975 Sky and Tel.
Posted 05 January 2013 - 06:31 PM
smelled like brand new, the paint and rubber smelled brand new, and the cords were still sealed in bags.
It fried the first time. Also wont work on AC
possibly should toss it
Posted 07 January 2013 - 10:06 AM
Posted 19 January 2013 - 11:55 AM
Larry packed it up and sent to me and when it arrived I pulled the cover of the unit and took a look. Larry had said that as soon as he plugged it in that it smoked. It didn't take long to see what part had fried. It was the power resistor. Actually it cracked in half it got so hot. Here is a picture showing it still installed in the circuit.
Posted 19 January 2013 - 11:57 AM
Here is what was left of the cooked one.
Posted 19 January 2013 - 12:14 PM
So with the transistors out of the circuit I powered up the unit. The rectifier section had no problems and was making 16 volts of clean DC.
The next day I brought the hand contoller into work so I could use the test equipment in my lab. I dissassembled the unit to see what was going on. I flipped over the circuit board and discovered the another resistor was cooked and broken in half. This thing took a real hard hit. Luckly I was able to take the pieces of the resistor and look at them under a microscope and was able to see the what was left of the color coding strips that determine it value. It was 680 ohm and the one right next was also of the same value. I replaced both of them.
Here is a picture of the back of the circuit board and the inside of the case showing were the resistor had burned the paint off the inside of the box and the two new resistors installed on the board.
Posted 19 January 2013 - 12:22 PM
Here is a picture of the hand controller board will all new caps and a Zener diode.
Posted 19 January 2013 - 12:27 PM
Dave, you are the epitome of the classic forum! You certainly have given good advise to me.
I'm sure Dave won't stop until the controller is better than new!
Posted 19 January 2013 - 12:39 PM
The problem is that the transistor (2SB187) used are vintage Japanese germanium units that at one time were very commonly used in radios but not any more. Luckily EBAY comes to the rescue and I found a cheap source there. So when they arrive I'll replace them and I hope that will get this section up and running.
Posted 20 January 2013 - 12:47 PM
Dave you really know what you are doing!
There are people in this world I admire, People loke Dave, also Guys that can do Body Work. I've tried and it come out looking like someone threw a handfull of mud on the fender...
Thanks again Dave.. Like you I also Love Criterion I have a great old RV6!
The DX6 Dynamax that tracker came with has outstanding optics, and is in mint "cosmetic" condition. Like that Dyna Track is.. Sure was a lot of smoke coming out of that thing.
Posted 31 January 2013 - 05:23 PM
So can anyone who has one of these unit please take the cover off the hand controller and take some close up shots so I can read the values of the parts and also turn the circuit board over and take a picture of it. It would be of great help in getting this unit repaired and back to Larry. I have traced the circuit and will post it once I get it working so others might be able to repair their unit in the future.
Posted 31 January 2013 - 07:04 PM
Hope someone steps up with the info ya really need!
Posted 01 February 2013 - 09:25 AM
The Criterion E-6 unit is 100% transistor based. It most likely was designed and built in Japan under contract to Criterion. The transistor based Flip/Flop as it is now doesn't make any sense and of course isn't working. I'm sure that either it was built wrong are some component(s) were not installed.
Posted 01 February 2013 - 11:14 PM
Anyway, in the 1970 article, there's more discussion about the first corrector diagram in a 1968 S&T Gleanings article. So maybe, you are running into some transistor based flip-flop issues that were later corrected. Or, maybe something isn't properly grounded? Grounding has gotten me once or twice in electronic circuits and I'm sure you've checked, but a reminder doesn't hurt
Posted 02 February 2013 - 09:13 AM