Homepage Crypto Spy sets Index USA USSR UK Gladio Other Burst encoders Intercept Covert Radio PC Telex Agencies Manufacturers Donate Kits Shop News Events Wanted Contact Links FS-5000 PSU Power Supply Unit The FS-5000 radio station can be powered from two rechargeable batteries (recommended), from an external 12V source (via the power inverter that is part of the battery charger), or directly from the Power Supply Unit (PSU) that is normally mounted on top of the battery charger.   The image on the right shows the PSU which has no controls. At the right is a socket for input from the mains. The wide-range PSU accepts any AC voltage between 110 and 240V. To the left of the mains socket is the main fuse (4A slow-blow). A spare fuse is stored below the plastic cap on top of the unit. At the bottom of the PSU are two large contact pins that carry the 14V DC output voltage. When the PSU is mounted on top of the battery charger, these pins line-up with similar pins in the top lid of the charger.      Interior The PSU is a Switched Mode Power Supply (SMPS) with a wide-range input (110-240V AC). The advantage of the SMPS principle is that PSUs can be made much smaller, as they don't need a bulky transformer, and are highly efficient (approx. 80% at the time this PSU was designed).   Because of the high voltages, a protective plastic cover is present between the PCB and the top lid. The image on the right shows the interior of the PSU after the plastic cover has been removed. The PSU consists of a single PCB with an SE5560 controller at its heart [1]. One of the disadvantages of an SMPS is that it generates rather strong (unwanted) spurious signals that can cause interference with the reception of weak radio signals. Such side-effects are generally classed as EMC-problems, which are extremely difficult to solve.    Although the designers of the FS-5000 made an enormous effort to avoid any EMC problems with this kit, the spurious signals from the PSU are not sufficiently suppressed. As the FS-5000 was specified for a range of no less than 6000 km, it was advised to power the radio station always from the batteries. In some countries a modification was carried out that made it impossible to connect the PSU/Charger to the transmitter. The modification consisted of a plastic panel that was mounted over the input connector of the transmitter.   References Philips (NXP Semiconductors), SE5560 Switched-mode power supply control circuit 31 August 1994. Retrieved April 2012. Further information FS-5000 charger Back to main FS-5000 page Any links shown in red are currently unavailable. If you like this website, why not make a donation? © Copyright 2009-2013, Paul Reuvers & Marc Simons. Last changed: Saturday, 21 April 2012 - 09:12 CET