Frye FONIX 7000 - Manual (Page 188)

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FONIX 7000 Hearing Aid Analyzer
10. Turn on the sound level calibrator and look at the “Probe Mic” level in the
Microphone Calibration window. It should match the calibrated tone emit-
ted by the sound field calibrator.
11. If necessary, adjust the gain of the probe microphone by using the Phillips-
head screwdriver to adjust the “probe” pot on the back of the remote mod-
ule of the 7000 Test System. Match the levels as close as possible. If you
are unable to adjust the gain of the microphone to the level emitted by the
calibrator, you probably have a faulty microphone and should contact your
local FONIX distributor or the Frye factory.
12. Press [EXIT] to return to the Opening screen.
B.2 Calibrating the insert earphone for the RECD
The real-ear to coupler difference (RECD) is a measurement that can be per-
formed when you have the Real-Ear Option (Quik Probe). There are two parts
to the RECD: a coupler measurement and a real-ear measurement. The coupler
measurement is considered a calibration procedure and needs to be done only
when the probe and reference microphones are calibrated.
The RECD measurement is usually done with a 50-ohm insert earphone.
Eventually, the 7000 Test System will also support an RECD method performed
with a linear hearing aid, but that has not yet been implemented.
1. Insert the earphone connector into the ¼ inch “Earphone” jack on the back
of the 7000 Test System.
2. Plug the other end of the earphone into the tubing of the ear level adapter
attached to an HA-2 coupler.
3. Attach a new probe tube to the probe microphone.
4. Thread the probe tube through the edged side of the probe microphone
adapter so that the probe tube sticks out a couple of millimeters from the
other end of the adapter. See the setup for calibrating the probe microphone
in the previous section. The probe microphone adapter is used in the same
manner.
5. Secure the probe tube in place by putting a dab of Fun-Tak on the edged end
of the adapter.
6. Insert the adapter into the HA-2 coupler.
7. Press [MENU] from the Opening screen to open the Setup Menu.
8. Press [F4] to perform the measurement. The screen will briefly display that
the measurement is being taken and saved. No further action is necessary.
9. Press [EXIT] to return to the Opening screen.