Technik und Service
Seite: 51
Technology and Service
Page: 51
mecablitz 44 MZ-2 / 44 AF-3
ENGLISH
TTL pulse:
In TTL mode, the light output is controlled by the TTL pulse from the camera. This is the first positive-going
edge (LOW-HIGH) on SK1 after a flash has been triggered (SYN). The activation of the IGBT TR401 by a
HIGH signal at Pin 4 of IC406B is terminated by the TTL pulse and the flash is switched off.
Wake-up by the camera:
When the flashgun switches itself off automatically, Pin 49 (+5V ON/OFF) of the µC IC401 switches to HIGH
and thus cuts off Tr406. This switches off the v5VG and the mecablitz switches to the power-saving
standby mode.
The mecablitz is switched on again (wake-up) when the user slightly depresses the camera shutter release.
When this is done, the camera switches SK3 to HIGH. Tr412 is driven via R4044 and starts to conduct. The
collector of Tr412, and thus the interrupt input at Pin 51 of IC401, is connected via resistor R4042 to the
v5.0V (which remains on in standby mode). When Tr412 starts to conduct, the level at Pin 51 of
IC401 changes from HIGH to LOW and an interrupt is triggered. This interrupt causes the µC to switch the
mecablitz on again. For this, the µC IC401 switches its Pin 49 (+5V ON/OFF) to LOW. Tr406 is thus switched
on and the switched v5VG is again available at its collector.
11. Technical Data:
Guide numbers with ISO 100/21° film speed and full light output:
Zoom position in mm
28
35
50
70
85
105
Metric
system 26 28 34 38 42 44
Imperial
system 86 92 112 125 139 145
Guide numbers with ISO 100/21° film speed and partial light output MLo:
Zoom position in mm
28
35
50
70
85
105
Metric
system
9 9,7 11,8 13,2 14,6 15
Imperial
system
30 32 39 44 48 50
Flash duration:
TTL flash mode
Manual flash mode
Partial light-output
mode MLo
Flash duration in
seconds, approx.
1/200 to 1/20000
1/200
1/5000
