HP RM500SL manual FastFacts 8.5 Ansi 2003 Linear and AGC tests

8.5ANSI 2003 Linear and AGC tests

1)Press <Tests>, then highlight and <PICK> [Linear] or [AGC].

2)Highlight and <PICK> [Start test]; test setup instructions will be displayed.

3)Refer to 7.11: Coupling the hearing instrument, 7.12: Positioning the hearing

instrument and 2.5: Battery pill use and care to prepare the instrument for testing.

4)Turn the instrument ON.

5)Set the gain control (manual or programmable) to maximum with all other controls set to provide the widest frequency response, greatest gain and highest maximum output. AGC controls and/or programmable parameters should be set to minimize AGC action (AGC off or threshold high, compression ratio close to 1).

6)Press <Continue> to run the test or press <Cancel> to abort the test. Note that, if required, the RM500SL will pause during the test to request that the gain control be adjusted to the Reference Test Setting (RTS). If necessary, open the HIT chamber and, without moving the hearing instrument, adjust the gain control until the large vertical arrow on the screen prompt disappears. Press <Continue> to resume the test.

During the AGC test, the RM500SL will pause to request that AGC controls or programmable parameters be set for maximum AGC effect. If the manufacturer does not provide settings to produce maximum AGC effect, use settings that result in the highest gain for soft sounds and the lowest gain for loud sounds. This will typically result in the lowest compression threshold, a flat I/O curve and the longest attack/release times. These are not “typical” characteristics but indicate the adjustment range possible for these parameters.

If you are unsure which test sequence to run, try [AGC] first. If attack and release times are all near zero, the instrument is probably linear.

FastFacts 8.5: ANSI 2003 Linear and AGC tests

0611 RM500SL User’s Guide Version 2.8 Page 40