539 Test Program  

Development  Tests   During the development phase, two waveguides  were subjected to a very detailed deve lopment test  program.  The successful performance in these tests is what  lead to the selection of waveguides for the  PSP program.  The development program was as follows:   1. Waveguide visually inspected at 80X ; no significant defects observed   2. RF performance ch aracterized in straight and 45 degree bent c onfiguration and was acceptable   3. Resistance torque was measured; max imum  resistance torque at 45 degree was less than   30 mN -m.  4. Waveguides were subjected to 4 00 flex cycles at ambient temperature between -45 degree  and  +45 degree and following this cycling, were visua lly inspected and characterized   a. No change in resistance torque after life cycle test   b. Visual inspection at 80X showed no new damages  or degradat ion of existing surface  blemishes   c. No changes noticed in RF  performance for either article  5. Waveguides  were subjected to sine survey and random vibration; f ollowing vibration  testing, the  waveguides were visually inspected and characterized  a. Visual inspection un der 10X did not show any issues   6. Waveguides exposed to two thermal cycles between - 125°C and +100 °C; at each temperature  extreme, waveg uides were subjected to 100 bend cycles between - 45 deg and +45 deg   a. Visual inspection under 10X did not show any issues for either article   b. No changes in RF  performance for either article  

Batch Qualification   The flight batch of the wavegui des were subjected to a test program consisting of batch qualification test  on one waveguide and acceptance testing on all flight and spare components. The first round of tests was   performed on waveguides with soldered flanges and resulted in failures  of some of the soldered joi nts as  described earlier . The program described in this section was performed on the waveguides with  electroformed flanges. Prior to the delivery of the waveguides the manufacturer performed 7 thermal cycles  between -105°C to +170°C and RF characterization.  

The qualification program was as follows:   1. Visual Inspection (20X to 80X)  of exterior and inspection of silver coating on interior with borescope   2. RF performance test   3. Radiography   4. Vibration Testing  - sine sweep, sine vibration and random vibration (Protoflight)   a. Visual Inspection showed no damage   b. No changes noticed in RF performance post vibration   5. Bend resistance measurement and 330 flex cycles over ±45° (110 @ ambient, 110 @+170°C and  110 @  -105°C)   a. Visual Inspection sh owed no damage   b. No changes noticed in RF performance post mechanical function test   6. Thermal Cycling (200 cycles between - 105°C and +170°C)   a. Visual Inspection showed no damage   b. No changes noticed in RF performance over the course of thermal cycling   7. Radiography  - no defect observed post thermal cycling  (Figure 10)   8. Removal  of side wall and visual inspection of the interior;  silver coating was found to be in good  condition (Figure 10)  

Acceptance Test   Five flight waveguides were subjected to the following tests:   1. Visual Inspection (20X to 80X)   2. RF performance test