14 • BX-8x7
© Box 73 Amateurfunkservice GmbH 2014
Additionally, the DYC-8x7 contains a
simple AF generator. This can be used to
generate a stable test tone for tuning an-
tennas, ATU’s or linear amplifiers, for
example. The AF generator is activated by
pressing the Down button on the micro-
phone while the PTT button is already de-
pressed. This can be done with one hand.
Please be sure to keep such tuning signals
as brief as possible and at the lowest pos-
sible RF power level, so as not to interfe-
re with other radio communications.
The standard functions of the microphone
buttons (Up, Down and Start Search) re-
main intact.
At high AF gain or when using the maxi-
mum compression level, be sure to listen
to your own transmitted signal and ask the
distant operator for an audio report. High
AF gain can cause background noise to
overwhelm the compressor circuit’s filter
threshold and be transmitted, especially
when a high compression ratio has been
set. This should be strictly avoided.
Good luck and have fun putting the kit to-
gether and using your dynamic compres-
sor on the air!
Literature
[1] Theurich, K., DG0ZB: Dynamikkompressor für
den FT-817. FUNKAMATEUR 51 (2002) No. 4,
p. 389
[2] FA-Bauelementeinformation SSM2165: FUNK -
AMATEUR 50 (2001) No. 12, p. 1357
Parts list
Name
Model/Value
Number
Comment
IC1
SSM2165-1P
1
C3
220 µF/10V
1
Tantalum
P1
Potentiometer 1 kΩ
1
P2
Potentiometer 100 kΩ
1
S1
Slide switch, 1-pin
1
Bu1, Bu2
RJ45 jack
2
on the board
Circuit board
Circuit board
1
SMDs mounted
TRX connector cable
1
with 2
¥
RJ45
Box
1
processed
Label
1
Construction manual
1