TM  55-4920-402-13&P (8) Test Balancer with double interrupter as fol- lows: (a)  Run  Tester  at  1800  RPM  and  push  and hold  TEST  button  on  Phazor  section. Verify that the 12:00, 6:00, and 1:00 O’clock lamps light. (b)  Release  TEST  button  and  observe clock angle of lighted lamp. (c)  push  and  hold  VERIFY  TUNE  button and adjust RPM TUNE dial to return light to clock angle observed in above step. (d) Release VERIFY TUNE button and observe new clock angle. Repeat until there is no change whether VERIFY TUNE button is pressed or released. Read clock angle with the  VERIFY  TUNE  button  released.  After tuning, verify that the Phazor indicates between 2:30 and 3:30 o’clock, the IPS meter reads between 0.72 and 0.88 IPS, and the RPM TUNE dial reads between 176 and 184 RPM. (e) Change RPM RANGE switch to Xl and RPM TUNE dial to 900. Set Tester CAM RATE switch to 900 RPM. Repeat steps (a) through (d), above. Verify that the IPS meter reads between 0.36 and 0.44 IPS and RPM TUNE dial reads between 882 and 918 RPM. (9) Test Balancer with single interrupter as fol- lows: (a) (b) (c) (d) (e) (f) Set  INTERRUPTER  LOGIC  switch  to SINGLE. leave others as set in step (4). Remove the two opposite pairs on interrupter screws on the Tester (four total) leaving only the two opposite single screws. Set tester motor switch to ON. Set Tester CAM RATE (RPM) and Balancer RPM Tune to 1800 RPM. RPM RANGE to X10 and push an hold TEST button on Phazor. Verify that only  the  12:00  or  12:30  clock  lamp lights. Release the TEST button and observe clock angle  of  lighted  lamp. Push VERIFY TUNE button and adjust RPM TUNE dial to return lamp to clock angle observed before button was pushed. Release VERIFY TUNE button and observe new clock angle. Repeat until there is no change between button pushed and released. Verify that the indication in the Phazor lights is between 8:30 and 9:30 o’clock, the IPS meter reads between 0.72 and 0.88 IPS, and the RPM TUNE dial reads between 176 and 184 (1800 RPM). (g) Set Tester CAM RATE (RPM) and Balancer RPM TUNE to 900 RPM. RPM RANGE to X1. Repeat steps (c) through (f) above. Verify that the IPS meter reads between 0.36 and 0.44 IPS and the RPM TUNE meter reads bet- ween 882 and 918 RPM. b. Adjustments. No adjustments can be made. 3-6. Strobex Checkout.  The Strobex is checked by the tester using Balancer unit. If the Balancer and Strobex checks  are  not  within  specifications  perform paragraph  3-8  below: a. Performance Check of the Balance Mode. (1) (2) (3) (4) (5) Connect VIBREX and Tester as shown in figure. 3-1. Set Tester CAM RATE switch to 1800 RPM. Set   Balancer   FUNCTION   switch   to A  or  B.  Set  Balancer  RPM  TUNE to  180  and  set  balancer  RPM  range switch  to  the  X10  scale.  All  other controls   are   unimportant. Set Strobex MODE switch to A. Set Tester rotor for double interrupter (all six interrupter screws installed, fig. 3-3). NOTE The Magnetic Pickup is not required, but it need not be disconnected. (6) Set Tester MOTOR switch to ON and illuminate Tester rotor with the Strobex. Verify that the stem of the h in the logo appears stopped in two positions. (7) Note the clock angle of the stem of the h in the logo. Push and hold VERIFY TUNE button and adjust RPM TUNE dial to return images to clock angle observed  before  button  was  pushed. Release VERIFY TUNE button and observe new clock angle. Repeat until there is no change whether VERIFY TUNE button is pushed or released. When  the  Balancer  is  properly  tuned, the stem of the h in the logo at the center of the disc appears stopped and double at 1:30 and 7:30 O’clock (fig. 3- 4). (8) Set Tester CAM RATE (RPM) and Balancer RPM TUNE to 900 RPM RANGE to Xl. Observe the same results as in step (7). b. Performance Check of the Track Mode. (1) Set Balancer MAGNETIC PICKUP switch to COMMON,  FUNCTION  switch  to  TRACK,  and INTERRUPTER LOGIC switch to DOUBLE. All  other  controls  are  unimportant. Change   4 3 -5