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====== Don Misc. Projects ======

===== Gull Airborne Instruments, Control Unit, Wing =====

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^115V, 400 Hz|
^Part No.|352-011|
^Contr. No.|N00383-89-C-4000|

This device consists of 3 round circuit boards, wired to a Canon end plug. One of the circuit boards has two burned components. On initial inspection, they appear to have become so hot that they melted the solder and came loose from the circuit board. The circuit board is somewhat charred, but not deformed.

Although there is no known schematic, it appears that these two components are Wire Wound resistors. They measured at 82 ohms each, and they are wired in parallel. Since they are apparently 3W resistors, the attempt is to act as a single 41 ohm 6W resistor.

The markings on these resistors are memcor RW69 V820. According to [[https://www.surplussales.com/Resistors/WireWound/WW800-10999.html|Surplus Sales of Nebraska]], these are:

^RW69-820|820 ohm|5%|3w|Wire Wound Resistor|

They have a $10 minimum, so hard to order. They also have 5w resistors of the same value (RW67-820 which are 5W), so may try to order these as well.

Not sure why these resistors burned out. Noticed that there is an old-school rectifier, which sometimes have a lot of leakage.

==== Conclusion ====

Need to check with Don to see if he wants me to:

  - Solder the existing resistors back on the board with heavier wire.
  - Buy identical resistors, and solder these back on
  - Buy the 5W (about 66% greater capacity) and solder these on

Ordered 4 3W resistors from DigiKey today 11/21/2019, Part # PPC3D820CT-ND. They are 16.5 mm long.

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