[MyHosting.com]   [KO4BB Home Page]   [Manuals Home Page]   [KO4BB Wiki]
 

Repair Coils on HP Attenuators

Just wanted to let you know I was able to repair and rewind the 4 damages bobbins.

I first tried using the original #35 AWG magnet wire size, but due to the physical repair I had to do on the damaged plastic bobbins I was not able to wind the same number of turns as the original coil, so the resistance was too low (about 42 Ohms instead of the original 50 Ohms).

The sink transistors in the 75468's are rated at 500mA maximum, so 42 Ohms at 24 VDC makes the current too high. It may have worked, but I did not want to risk it. I changed the wire size to #36 AWG and ended up with about 60 Ohms.

After finishing the bobbin repair and rewind, the attenuator actuators work great and I now have a working generator.

The rubber grommets that physically attach the plastic attenuator arm to the actuator are starting to dry out and will be a problem sometime in the future. Any suggestions on replacements?

Thank you again for all the information and your help with the project.

Steve

 
test_equipment/repair_coils_on_hp_attenuators.txt · Last modified: 2013/01/08 19:00 (external edit)
 
Recent changes RSS feed Creative Commons License Donate Powered by PHP Valid XHTML 1.0 Valid CSS Driven by DokuWiki
Except as noted, this entire site Copyright © 2002-2017. KO4BB All rights reserved.