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I am in the process of replacing cracked and leaking capacitors in an old 1970s Johnson Viking 4740 transceiver. But, what I thought would be a simple swap, wasn't. The modern version of these capacitors have markings that don't relate to the ones I have pulled. I have searched all over the internet and can find nothing resembling my problem. There must be others with this problem, or will be in the future. Can anyone "translate" these for me? Any/all help will be appreciated. Unknown capacitors Unknown capacitors

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  • \$\begingroup\$ Welcome to EE.SE. Yes, those look a bit old and worn out. \$\endgroup\$ – Sparky256 Feb 26 '18 at 4:04
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Yes. These are old mylar capacitors before a unified coding system was implemented. But the codes are easy to read, as during this period in history the nF was the point of reference unless xxpF was used to imply that this value was in pF. 0.03K meant 30nF. 0.15K was 150nF. 0.01 is 10 nF, etc

They look a little aged in the photo. You might consider replacing them with new ones.

Electrolytic capacitors had and still have the actual values on them, including a temperature spec such as 150C.

This is a photo of an old style mylar capacitor. 100.77 nF 100 volt.

enter image description here

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  • \$\begingroup\$ They all appear to be 10% tolerance and rated 50 volts. \$\endgroup\$ – AlmostDone Feb 26 '18 at 4:23
  • \$\begingroup\$ Would the .1K then be 100nf and what are the 2 zeroes for, in the 005 50? \$\endgroup\$ – Johnno Feb 26 '18 at 4:24
  • \$\begingroup\$ "during this period in history" ... we didn't use nF. So, all those markings are in uF. The K is something like a temperature coefficient. The 50 means 50 volts, typical for this type of capacitor. \$\endgroup\$ – gbarry Feb 26 '18 at 4:34
  • \$\begingroup\$ @AlmostDone. You are likely correct. \$\endgroup\$ – Sparky256 Feb 26 '18 at 4:47
  • \$\begingroup\$ @Johnno. 005 is 5 nF and 50 volts. The ink is worn off of some of these, but body size coincides with capacitive value, if these are all 50 volt rated. \$\endgroup\$ – Sparky256 Feb 26 '18 at 4:50

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