Sommerkamp TS-680EDX, Instruction Manual

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TRANSMITTER & MODULATOR SECTION:
The tr a s m it t e r s e c tio n is désignée! fo r c o n tin o u s heavy d u ty tra n s m is s io n o f
a m p litu d e m o d u la te d (A M /A 3 ) s ig n a is in th e 2 6 .9 6 5 to 27.855 MHz. (11 m e te 'r)
c itiz e n s band.
The t r a n s m it te r c o n s is ts o f a P hase Locked Loop c ir c u it and an o n e - c r y s ta l
c o n tro lle d o s c illa to r, o f w hich o u tp u t is syn th e size d in a d a s s B m ix e r, fo llo w d
by a d o u b le tuned f ilt e r , d a s s A B I b u ffe rs , and a h ig h ly e ff ic ie n t c o lle c to r -
m o d u la te d d a s s C d r iv e r and pow er o u tp u t stage, coupled by s é rie s and p i-
m a tc h in g f i lt e r s to th e a n tenna ja c k .
The m o d u la to r c o n s is ts o f an in p u t a u d io f ilt e r , ALC a m p lifie r in te g ra te d pre-
and p ow er a m p lif ie r - -and m o d u la tio n tra n s fo rm e r. T h is g iv e s you th e lo w e s t
p o s s ib le m o d u la tio n d is to r tio n and up to 1 0 0 % m o d u la tio n .
The in p u t is d e sig n e d fo r 500 ohm d y n a m ie m ic ro p h o n e o r 32 ohm s p e a k e r/
m ic ro p h o n e c o m b in a tio n w ith a 1K ohm r e s is to r in s é rié s .
RECEIVE/TRANSMIT SWITCHING
T h e r e c e iv e /t r a n s m it s w itc h in g is done by a s in g le pole, s in g le th ro w s w itc h
in th e m ic ro p h o n e and a c o m b in a tio n o f NPN and PNP s w itc h in g tr a n s is to r s .
METER
The c o m b in a tio n m e te r p ro v id e s you w ith th e fo llo w in g fu n c tio n s :
D u rin g re c e iv e m o d e ..................i t in d ic a te s th e in c o m in g s ig n a l s tre n g th .
D u rin g tr a n s m it m o d e ............. i t in d ic a te s th e o u tp u t power.
For n o rm a l o p e ra tio n , be su re i f th e RF G A IN knob is pushed.
For c h e c k in g th e SWR o f y o u r antenna, p u ll th e RF G A IN knob, th e n th e m e te r
w ill fu n c tio n as SWR m e te r.
MOBILE INSTALLATION
M o u n tin g b ra c k e t and s cre w s a re s u p p lie d fo r m o u n tin g th e tra n s c e iv e r under-
n e a th th e d a shboard. M icro p h o n e hanger and s c re w s are a ls o su p p lie d . For
e le c tr ic a l c o n n e c tio n , f i r s t m ake su re th a t the tra n s c e iv e r is tu rn e d o ff.
C o n n e ct th e red w ire to th e ACC te rm in a l o f th e ig n itio n s w itc h o r + te rm in a l
o f b a tte r y and ground th e b la c k w ire to th e c h a s s is o f th e re h ic le . T h e b la c k
w ire s h o u ld be grounded as s h o rt as p o s s ib le to m in im iz e n o is e in te rfé re n c e .
T h is tra n s c e iv e r is d e sig n e d fo r use w ith th e n e g a tiv e ground s y s te m .
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