[Patrick]

I know this shoud be an easy problem for most of you, but I guess my mind doesn't work like it used to. What wattage resistors can I use to replace  the #77 candohm (780Ω, 268Ω, 28Ω, 26Ω)?

[Image: http://i1367.photobucket.com/albums/r796...od7zcy.jpg]

[codefox1]

Well, please try to find out why the voltage divider failed. It is statically more likely that a capacitor was at fault rather than a segment of the resistor element , but heat, ets.. could present a difficult diagnosis. It is well known that excessive temperature could compromise the insulation of candohms to the point of arcing to chassis. Artifacts are sometimes difficult to detect, even with a sharp eye. An approximation of the needs downstream of the voltage divider should give an idea of replacement values, to be mounted as close to original position as possible, and heat sinked to chassis for the first stage or two. Of course, a suitable ammeter should be used whils powering up the supposed fix to see if current is sinking elsewhere.

[Patrick]

Well, please try to find out why the voltage divider failed.  It is statically more likely that a capacitor was at fault rather than a segment of the resistor element , but heat, ets.. could present a difficult diagnosis. It is well known that excessive temperature could compromise the insulation of candohms to the point of arcing to chassis.  Artifacts are sometimes difficult to detect, even with a sharp eye.  An approximation of the needs downstream of the voltage divider should give an idea of replacement values, to be mounted as close to original position as possible, and heat sinked to chassis for the first stage or two.  Of course, a suitable ammeter should be used whils powering up the supposed fix to see if current is sinking elsewhere.

The candohm was removed by a previous owner, and 1 watt resistors sloppily put in their place.

[DKinYORKpa]

I just replaced both of the candohms on my 38-690. I was fortunate to find voltages over at the other forum. OHM's LAW then gave me my wattages that I then tripled! Without the actual voltages at each resistance, it would take knowledge that I lack to determine the current.

[Nathan Slingerland]

Great job!

It would be most helpful for the next restorer with the same issue if you could post the voltages and resistor values for reference.