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b) The second main part of the ACOM2000SW, i.e. properly the switch,
comprises 10 identical electro - magnetic actuators. Every actuator moves a
separate flat coaxial line shaped spring contact. The strips are gold over
silver plated and the line characteristic impedance is 50 Ohm for minimum
RF reflections, best feed line homogenity, and maximum crosstalk isolation.
All 10 lines begin from a separate UHF type (SO239A) connector and are
directed to the center. Their contact ends normally lay on the chassis plane
(i.e. are grounded). When any contact is being actuated, it transfers to a
central collector disc to connect to the common UHF connector. The
central collector disc is massive brass and gold over silver plated, too. The
result is a very quick heat diffusion from the contact area.
The contact ends are bifurcated and the two branches are different length.
This, along with the goldened contact surfaces, improves the long - term
contact reliability and ensures a nonlinear - free reception, even at extremely
low signal levels.
The signal detector PCB (D1) and its current transformer (TA) are mounted
directly on the central common connector.
4-2. Troubleshooting
If any function is not properly executed, check control unit first and then the
external cabling (S.2-3). At the cable end, check the power supply voltage
(+27VDC), its behavior during switching, and also the control BCD code
and code low and high levels. See S.5-1 g, h for specifications. Check all
cables for continuity and/or short circuit. If the problem persists, contact
your dealer first or ACOM directly - see S.1-2.
