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9090db floating resistors???

those resistors, and the 2 that "floated" :)
Look like metal oxide, but am guessing were ceramic?

OK to replace with Metal oxide, or would wirewound be better?
 
xratedpez said:
those resistors, and the 2 that "floated" :)
Look like metal oxide, but am guessing were ceramic?

OK to replace with Metal oxide, or would wirewound be better?
Click to expand...

Metal oxide/Metal film 2 or 3 watt for the floaters and ½ watt for the ones DCinDC mentions - definitely not wirewound.
 
xratedpez said:
In general, no wirewound in signal path? How come? Thirsty for info.
Click to expand...

Standard WW resistors have a lot of inductance, which can increase total impedance quite dramatically at high audio frequencies. You can buy non-inductive WW resistors, for a bit more money, and you can pretty much ignore the whole issue if resistor value is relatively high. Inductive reactance becomes a small fraction of total impedance in high-value resistors.
 
Got parts, found another misprint... Those smaller resistors DCinDC mentioned at top are 100 ohm (but read higher). Picked up 2 metal oxide 1-watters at radio shack to do the trick there. One of the 50V 1uf Electrolytics from tnsilver's list (and the service manual) is actually a NPE (not polar as listed)... so weird. definitely original, but the other 3 of the same value on the board are polar.

Wonder how many variations of this relay board there are? hah.

Sooooo... going to put another order in anyway. :D
 
Here's a photo of the (4) 1uF caps from the power relay board F-2657

1 of them (on the bottom) is non-polar, which contradicts everything I've seen documented to this point.


45cd17f9-5956-3de8.jpg
 
No polarity markings, it reads 50V 1uF NP.

Also: I think using a NPE in place of a polar is safe, but perhaps not best sonically due to nature of NPEs, if located in the signal path. EW or others may have more thoughts/info on this.
 
Cool man! Hey- look at it this way, the Service Manual doesn't mention it either... :D

The best, Jerry, the best!!!
 
So, thinking pragmatically here... Do I really need to replace the ceramic capacitors?

In order of impact on sonic improvement, would the following replacement list be accurate: (?)
  1. Electrolytic
  2. Mylar
  3. Polystyrene
  4. Ceramic

Also, any pointers on which boards to fully recap first (beside the power relay board, which is done)?

I don't mind replacing a ton of caps, but I want to make this worthwhile... Wondering if ceramics are worthwhile.

Thanks pros !!
 
xratedpez said:
So, thinking pragmatically here... Do I really need to replace the ceramic capacitors?

In order of impact on sonic improvement, would the following replacement list be accurate: (?)
  1. Electrolytic
  2. Mylar
  3. Polystyrene
  4. Ceramic
Click to expand...

90% of the time you simply don't need to change anything but the electrolytics.

xratedpez said:
Also, any pointers on which boards to fully recap first (beside the power relay board, which is done)?
Click to expand...

Recap anything to do with the regulated power supplies first (if that isn't the board you have already done - above)

xratedpez said:
I don't mind replacing a ton of caps, but I want to make this worthwhile... Wondering if ceramics are worthwhile.
Click to expand...

No, electrolytics only, unless you can see that the other types are physically damaged in some way. (overheated, chipped etc). I might change the two capacitors associated with those resistors that fell off - but only because they were 'at the scene of the crime'

xratedpez said:
Thanks pros !!
Click to expand...

Not a pro - just an amateur who thinks he knows a bit more than most :smoke:
 
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Any suggestions on P/S filter caps? 12000/80V here, correct? Can't seem to find much info on replacements for these for some reason (there's a plethora of info on replacing everything else!!) :D
 
Thanks Tom. I'll pull those and measure with my caliper and report back. I tend to do lots of research on P/S caps to make sure they fit before I order.

You saved me all that time with the rest of them, I'll be happy to carry the load for these 2 :yes:
 
Forgot what the termination style on the stock Filter caps are.. Snap-in? Didn't think they are screw, but screw tend to be easier to work with, methinks.

Oh, and- Newark's got the proper datasheet posted. :)
 
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