Syncrowave 250 Control Board Part List PC1 needed

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This is my first Post. I successfully  repaired the control board 5 years ago but it has failed again.the problem is the schematic in TM-353D for the control board does not give any values or part numbers for the control board components. you have to read the values off the parts themselves which is normally  fine but this time resistor R121 has completely burned up and i don't know the value. Does anyone have a parts list for the control board or maybe you might have the value of R121? The Control Board part number is 132887 and the Resistor Value needed is for resistor R121. I'm avoiding buying a replacement board for $400
Reply:I have a synco wave 250. Will see what I can do
Reply:I have some service manuals for Sync 250s of various vintages...send me your serial number and I might be able to look up a part number or send you a schematic.
Reply:Well i was hoping to send along this info, but i have the same problem with a different component on a different PC1 from you.   Anyone got a value on R90 on PC1 138307?These things don't really work too well covered in magnetic dust... lol.Miller Syncrowave 300(s)Miller 330 A/BPMiller CP-200 Haas / Kamp'd / CP-300 in processMiller Radiator 1Miller 30A /S-52E feedersHobart GR-303
Reply:What's the first part of your serial number? Should start with L probably. Gimme the first five digits/characters so I can make sure I'm looking at the right P/L.Somebody over at the Miller forum might be able to help, too. And Miller4Less.com is often decent on parts prices.
Reply:Originally Posted by KelvinAnd Miller4Less.com is often decent on parts prices.
Reply:Kc.  That's why I'm fixing myself!!!  I can solder Sent from my LG-TP450 using TapatalkMiller Syncrowave 300(s)Miller 330 A/BPMiller CP-200 Haas / Kamp'd / CP-300 in processMiller Radiator 1Miller 30A /S-52E feedersHobart GR-303
Reply:Hey Spinroyd,According to my manual the R121 resistor is a 1/4 watt 392 ohm resistor.  Orange White Brown RedHope this helps.Doug Attached ImagesLast edited by Doug_; 04-24-2021 at 12:07 AM.Doug  Millermatic 200  Lincoln AC-225  Syncrowave 250
Reply:I am looking for a schematic for this board. Do you (or anyone else) have a schematic for the shunt resistor version (135254) of the control board? My syncrowave 250 is exhibiting full output with no current control. Everything checks out, SCRs, shunt, filter. The control board is getting current feedback from the shunt but not regulating the phase angle of SCRs to maintain the selected current. I can repair this however, a schematic would make my life easier. Mark
Reply:Hi All, I went to the Miller site and found the owners manual for the machine. It also has all of the needed schematics (although a bit hard to read some of the component numbers). As I decipher the schematic, I would appreciate if anyone that had done similar work on these boards chime in to give me some hints.