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  1. Tha fios agaibh

    Unknown capacitor.

    I believe this is it. It has an absolute max of 60ma, and draws 20ma with a typical 1.2v.
  2. Tha fios agaibh

    what is the different between speaker wire and power wire

    Speaker wire usually has more strands in it for flexibility. Unless you have a huge amplifier or have speakers located far away from the amp, using #10 is probably overkill. Yes, you can see the aluminum underneath the copper cladding on the ends where its cut off. Aluminum clad is popular in...
  3. Tha fios agaibh

    Unknown capacitor.

    I don't think so, I'll look again tomorrow. Thats one downside to having tiny components.
  4. Tha fios agaibh

    Unknown capacitor.

    Unfortunately not. You may right though, and its definitely a good idea to try some lower values first, but I can't square the math of why they use a 3.3k current limiting resistor with the isointerrupter led. From everything I read, the If of a ir diode needs to be at least 10ma and have a Vf...
  5. Tha fios agaibh

    Unknown capacitor.

    There is only a 100uf 50v smoothing cap next to it (C3) which could be rated much higher than final voltage rail so that's not much to go on. What I was figuring is the opto interrupter ir diode probably draws about 15ma @ 1.2Vf and it has a 3.3k resistor in series with it. That'd put the supply...
  6. Tha fios agaibh

    Unknown capacitor.

    I don't understand the codes other than u68 for .68uf, 305v rating, and its a type X2 film cap which I understand to be more robust and less likely to explode at end of life. What I'm now trying to figure out is how to determine the zener value in the ps. There's a optointerrupter that has a...
  7. Tha fios agaibh

    Unknown capacitor.

    Good idea I'll try that if it won't focus on lettering. I get the idea POS means something other than what I'm thinking.;) Meanwhile, I came across the same value film cap in my shop that I've used in similar applications. My camera performed well in capturing this one. The same manufacture but...
  8. Tha fios agaibh

    Unknown capacitor.

    ....well, I did preface the sentence with "if".
  9. Tha fios agaibh

    Unknown capacitor.

    Right, at least that's what I tough it said. I could be wrong. I will put it under serious magnification when I get back Monday and take a better picture. What kind of current should we be looking at here ahead of the bridge? If it was a .0065uf (652 on first line) Xc @60 hz would be 408k and...
  10. Tha fios agaibh

    Unknown capacitor.

    The bridge checked out ok with my dvm. The challenge is figuring out what the zener value should be. I'm guessing its a 5.1v Good catch kellys_eye, I thought second line said w60 but it could be u68. (My eyes aren't what they used to be) It certainly make more sense than a cap failing to a...
  11. Tha fios agaibh

    Unknown capacitor.

    I'd think it'd be way over the knuckle for 240v mains considering 339v peak. The 250v rating may even be a bit close with our 170v peak. I'd take another picture of the cap but unfortunately it's across town.
  12. Tha fios agaibh

    Unknown capacitor.

    Sorry, I couldn't upload full resolution because of file size but it definitely says 652. The photo was the best I could get of the little guy @ 1mb. Perhaps this is not a 3 digit code like found on smaller ceramic caps? Yes, bottom line looks like W60 250
  13. Tha fios agaibh

    Unknown capacitor.

    That black thing U2 (3rd picture) is a photo switch that senses when the punch carriage returns. Its got a led on one side with a 3.3k limiting resistor, I don't know the specs, but perhaps we can figure out the ps/zener voltage based on that sensor. Alas, I've got other projects to tackle this...
  14. Tha fios agaibh

    Unknown capacitor.

    Perhaps its good, but It definitely says 652 on the right hand side. Question is, what voltage?
  15. Tha fios agaibh

    Unknown capacitor.

    That black thing U2 (3rd picture) is a photo switch that senses when the punch carriage returns. Its got a led on one side with a 3.3k limiting resistor, I don't know the specs, but perhaps we can figure out the ps/zener voltage based on that sensor. Alas, I've got other projects to tackle this...
  16. Tha fios agaibh

    Unknown capacitor.

    Steve! You are the man! Yes, there's a zener thats shorted ahead of it. So I guess the shorted DC side was enough for the AC side of the bridge to collapse also. Here's the 652 giving a rare capacitance reading.
  17. Tha fios agaibh

    Unknown capacitor.

    Here's what I found. Cap C2 does in fact read 680nf (.68uf) but should be 6.5nf as Dave pointed out. So yes, it appears to be the problem.
  18. Tha fios agaibh

    Unknown capacitor.

    The teeny devices all read .7 vd one direction so they appear to be healthy transistors. Black 3 term thingy is a triac to turn on motor driven punch. Yes, the 6 terminal IC is an opto isolator. Of course with no voltage rail nothing will come alive. Thanks, I'll keep you posted when I get back...
  19. Tha fios agaibh

    Unknown capacitor.

    Yes, exactly. I'll take another look at it when I get home and sketch something up if I have time. The cap was suspect because I read ~120v across resistor parallel to it.
  20. Tha fios agaibh

    Unknown capacitor.

    Thanks Dave, I wish they would just mark the actual value since there's room for it. Forgive the capacitor passing voltage comment. I was thinking of its Xc resistance dropping line voltage as hevans1944 mentioned.
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