Save Old Iron 1,563 #1 Posted November 28, 2014 I'm putting the cart before the horse on this one but I wanted to thank forum member COD (Steve) for loaning me a defective WH418a indicator pcb to develop a repair test fixture. Steve, I will post the full "story" behind the repair but I wanted to let you know how your contribution will make it possible to effectively and economically repair and upgrade indicator boards for WH 300 and 400 series tractors . Many more secrets have been given up as to how the indicator board functions and what the various failure modes are for the individual components on the board. I was able to make modifications to the circuitry to VASTLY increase the reliability of the board assembly. I'm sure the test jig will evolve as I investigate any wiring changes need to accommodate the 300 series tractors. Right now wires are everywhere! 15 Share this post Link to post Share on other sites
cod 116 #2 Posted November 29, 2014 Chuck, Neat test fixture!!! The photos lead me to a couple of questions the first being about the connector you've used to connect to the board. Would it be possible to replace the the current connector that Wheel Horse used on the tractors where you push the wires into the "V" and improve the connections to the board? Is the lower photo of new board that you've come up with? It looks too clean to be the one I mailed... Steve 1 Share this post Link to post Share on other sites
Save Old Iron 1,563 #3 Posted November 29, 2014 No sir, that is your board, cleaned w/ the modifications installed and fully fuctional. I'll send you a PM with a few additional details. 1 Share this post Link to post Share on other sites
boovuc 1,090 #5 Posted December 7, 2014 SOI.................you never cease to amaze me. 1 Share this post Link to post Share on other sites
AJ_Thanatos 516 #6 Posted December 12, 2014 No sir, that is your board, cleaned w/ the modifications installed and fully fuctional. I'll send you a PM with a few additional details. Can anyone else be involved in the additional details. When it comes to circuitry Im all ears!! Share this post Link to post Share on other sites
Save Old Iron 1,563 #7 Posted December 12, 2014 Can anyone else be involved in the additional details. When it comes to circuitry Im all ears!! I'm not holding back or restricting details regarding the repair. I'm trying to gather additional info from COD on timelines, return addresses, etc, to return the repaired indicator pcb and the repaired rectifier/ regulator assy. Before I return the pcb, the bare copper repair traces need to be protected by UV curable coating. The coating and the UV oven are scheduled for delivery in the next few days. Stay tuned.You will not be disappointed. 2 Share this post Link to post Share on other sites
Save Old Iron 1,563 #9 Posted December 13, 2014 just a small teaser ... 1 Share this post Link to post Share on other sites
Coadster32 793 #10 Posted December 13, 2014 That oven is cool. Shake-and-bake SOI!!! (Love the Superman Squirrel picture) Share this post Link to post Share on other sites
bmsgaffer 2,043 #11 Posted December 14, 2014 SOI, that is starting to look like a pretty labor intensive process. Just out of curiosity, would it not be easier to come up with a "universal design" PCB (or even just a few different varieties) that takes into account a few different models with your circuit upgrades and just have it manufactured? 1 Share this post Link to post Share on other sites
Molon_Labe 731 #12 Posted December 14, 2014 SOI, that is starting to look like a pretty labor intensive process. Just out of curiosity, would it not be easier to come up with a "universal design" PCB (or even just a few different varieties) that takes into account a few different models with your circuit upgrades and just have it manufactured? I would love to find a bare board, the one that came off my 416-8 was damaged beyond reasonable repair. 1 Share this post Link to post Share on other sites
Save Old Iron 1,563 #13 Posted December 14, 2014 (edited) SOI, that is starting to look like a pretty labor intensive process. Not when put in perspective. "Labor intensive" is a common denominator in all apects of this hobby. Labor tends to show itself as the buy in price to become accomplished in the hobby. Ask yourself which one of us hasn't spent inordinate amounts of time, money and labor removing stuck roll pins or wheel hubs, de-rusting (and sometimes re-rusting), and polishing parts on our tractors.I happen to see pursuing an education and developing an understanding of internal workings of the project as one of the more rewarding aspects of the hobby. Plus, I might wager a bet COD will have a smile on his face when he gets his indicator pcb and RR back, both saved fom the landfill. A universal board is a good idea - IF the wiring configuration to the indicator pcb remains constant, pin for pin, across all models. From what I have observed so far, pin for pin compatability across models is a problem. I have seen some models use a switched ground for the parking brake indicator, others use a switched +12 volts. Edited December 14, 2014 by Save Old Iron 6 Share this post Link to post Share on other sites
bmsgaffer 2,043 #14 Posted December 15, 2014 (edited) Not when put in perspective. "Labor intensive" is a common denominator in all apects of this hobby. Labor tends to show itself as the buy in price to become accomplished in the hobby. Ask yourself which one of us hasn't spent inordinate amounts of time, money and labor removing stuck roll pins or wheel hubs, de-rusting (and sometimes re-rusting), and polishing parts on our tractors.I happen to see pursuing an education and developing an understanding of internal workings of the project as one of the more rewarding aspects of the hobby. Now you know I can't argue with that. You have to take it apart to figure out how to put it back together, can be the toughest and most rewarding part. I have often considered the home-fixed PCB route and I see you have gone all the way to solder-mask which I always found start-up cost prohibitive. Are you going to be using this for other projects I assume? From a fellow 'lectronics nut. Edited December 15, 2014 by bmsgaffer 1 Share this post Link to post Share on other sites
GlenPettit 1,714 #15 Posted December 15, 2014 How did you clean that "now-new" board? Your process: Cleaners, chemicals, 'tooth brush', air, drier ? A clean board might reduce some problems, and can the entire board be encapsulated? Glen Share this post Link to post Share on other sites
Save Old Iron 1,563 #16 Posted December 17, 2014 Glenn. the manufacturer dips the boards in a rubbery conformal coating that comes off fairly well by mechanical means. Tugging, snipping and scraping yields a clean pcb. Dental picks, Isopropyl alcohol and a toothbrush complete the task. 4 Share this post Link to post Share on other sites
Aldon 4,826 #17 Posted December 17, 2014 An idea which you may already have considered that might make a universal board more plausible would be possible use of dip switch(s) for inputs to route the inputs differently ..... 1 Share this post Link to post Share on other sites
bmsgaffer 2,043 #18 Posted December 17, 2014 An idea which you may already have considered that might make a universal board more plausible would be possible use of dip switch(s) for inputs to route the inputs differently ..... Share this post Link to post Share on other sites
Save Old Iron 1,563 #19 Posted December 18, 2014 An idea which you may already have considered that might make a universal board more plausible would be possible use of dip switch(s) for inputs to route the inputs differently ..... Aldon, thanks for the suggestion. The automotive and outdoor equipment environment is quite the challenge in which to design long lasting and stable electronics. Think of the tractor that may be stored outdoors in below zero weather snowy weather, then high humidity and scorching hot summers. Add in high vibrations once the tractor does start and this combination can loosen parts, shake both switches and wiring to the point of eventual failure. If the electronics survive all this abuse, wait until the tractor fails to start and someone jumps the battery with sparks flying after resetting the jumper cables !! Very , very hostile environment for electronics design. Even in a controlled environment, with moderate temperatures and humidity, dip switches tend not to be the most reliable part on a circuit board. In the "old days", back in the 80's and early 90's, we used dip switches to set baud rates on equipment connected to data management systems via RS232 serial protocol. When faster computers allowed faster baud rates, we reset dip switches to accommodate the faster baud rate speed. These switches had been sitting in one position for nearly a decade and did not like being flipped to another position - a significant number of them failed to work reliably after being exercised. Circuit breakers are another part that fail frequently in a high vibration environment. 2 Share this post Link to post Share on other sites
Aldon 4,826 #20 Posted December 18, 2014 (edited) Ok. Good points. Iguess that you guys have also thought about a short adaptor cable might fit the bill to allow a single hardened new universal board to be swapped in. it's obvious you guys are well versed and experienced and the rest of us are along for the trip:-) It's great to follow along. Edited December 18, 2014 by Aldon Share this post Link to post Share on other sites
Save Old Iron 1,563 #21 Posted December 19, 2014 An idea which you may already have considered that might make a universal board more plausible would be possible use of dip switch(s) for inputs to route the inputs differently ..... Aldon, not DIP switches, but maybe jumper wires which can be snipped to give the pc board its "personality" setting. If I had to bet my lunch money on a new direction, I'm thinking the design will be based on the current sub $1 controller chips in the ATTiny family. 2 Share this post Link to post Share on other sites
wrightorchid 261 #22 Posted December 19, 2014 I have a 300 series board if you need one to play with/ restore. Share this post Link to post Share on other sites
bmsgaffer 2,043 #23 Posted December 19, 2014 I have a 300 series board if you need one to play with/ restore. I do I do! I'm trying to develop a replacement for those that cant be repaired by SOI. I will send you a PM Share this post Link to post Share on other sites
Save Old Iron 1,563 #24 Posted December 30, 2014 (edited) Steve. the UV cure moisture-proofing paint finally arrived. I should have some news for you later this weekend. Edited December 30, 2014 by Save Old Iron 2 Share this post Link to post Share on other sites
cod 116 #25 Posted December 30, 2014 Chuck, Thanks for the update as it looks just like those eel guts I had to try many moons ago. Hopefully this will seal the board as you plan as the guts didn't stay sealed in me at all... Steve Share this post Link to post Share on other sites