Panasonic KX-F680BX, Руководство по обслуживанию

Страница: 68 / 146

|
74
|
KX-F680BX/KX-F2681BX
3-9. DIGITAL SPEAKER PHONE SECTION
Digital speaker phone is different from analog speaker phone.
What's different? Previous type (analog speaker phone) is to switch Tx or Rx. Either Tx or Rx is able to pass a telephone
line or speaker, it depends on the Tx and Rx signal (voice) level. Bigger one is able to be passed the route for that signal.
So you never hear voice from other party while you are talking. But in the digital speaker phone feature you can hear voice
from other party while you are talking. So both Tx and Rx are alive at the same time such a talk-show with telephone on TV
program you have watched. And troubleshooting is also different from previous type.
You may think that speaker phone works with speaker phone key pushed. But Tx is muted just after speaker phone is
turned on (this is not full-duplex), makes tel line connecting, output dial tone and then speaker phone is actually started.
Speaker phone is still muted while unit is detecting call progress tone, so speaker phone won't work when you only push
that key.
In order to make speaker phone turned on firmly, we need push the speaker phone key with handset off-hooked or turn the
call progress tone off under the telephone line connected.
You do off-hook, push the speaker phone key and on-hook, you hear a dial tone that is decreased after you push the
speaker phone key. Such a decreasing tone you hear means that speaker phone is starting up.
We can't check it with previous method that we check it by a speaker phone key and making a speaker phone pass
(signal route). Because level is changing for above reason.
Therefore we prepare the service function for this troubleshooting. In this service mode we can set the mute either Tx or
Rx you want. So we can check the signal route of speaker phone Tx or speaker phone Rx without disturbance.
OFF HOOK
ON HOOK
push
speaker phone
D
......
D
........
D
....
Du
.............
Du
............
Du
..................
white bigger tone normal tone
tone signal
working as a monitor
and detection for DTMF tone working as the
digital speaker phone