====== Sangean ATS-818 ====== Manufactured by [[Sangean]], Taiwan. More popular than the travel radio **ATS-818** was its sister model **[[ATS-818CS]]**, which came with a built-in cassette recorder. {{:images:sangean-ats818cs.jpg?direct&400|Sangean ATS-818}} ===== Technical data ===== * [[Principle]]: [[Double conversion superhet]], [[IF]] 49.995 MHz / 450 kHz / FM 10.7 MHz * [[Operation modes]]: [[A1]] with BFO, [[A3|AM (A3)]], [[F3|FM (F3)]] * [[Frequency range]]: FM, LW, MW, SW (150 kHz - 30 MHz) * [[Frequency display]]: [[Digital display]], 10 Hz * [[Frequency memories]]: 45 * [[Signal strength indicator]]: LCD bar display * [[Signal processing]]: IF filter narrow / wide, [[RF Gain]] * [[Features]]: Frequency input keypad, clock, timer * [[Sensitivity]]: [[A3|AM (A3)]] / [[Selectivity]]: kHz (-6/-60 dB) ==== Power supply ==== * [[Batteries]]: 4 x 1.5 V ([[UM-2]]), 1 x 1.5 V ([[UM-3]]) for quartz clock / memory retention ==== Dimensions ==== * 300 x 190 x 80 mm, weight 1.8 kg ==== Accessories ==== ===== Operation ===== Sangean's ATS-818 was developed around 1992. Its sister model, which has an integrated cassette recorder in similar cabinet dimensions, was more popular: with this set, exotic station IDs could be recorded at the push of a button. The Sangean ATS-818 has a plastic cabinet measuring 300 x 190 x 80 mm and has a weight of 1.8 kg, it is quite bulky for a travel radio. To power the set, four D cells [[UM-1]] or a 9 V external power supply are needed. Three UM-3 AA cells are required to operate the quartz clock and to store the transmitter memories. The set is switched on with the red power button at the top right of the front panel; the volume control is located on the right-hand side of the set. At the bottom right of the front panel are the switches for timer operation, the IF bandwidths and the BFO. Below are the controls for tone, [[RF gain]] and the [[BFO]] control, which activates the heterodyne oscillator for [[A1]]/single sideband reception. The frequency ranges are called up with the keys below the display: the [[FM]] key selects the FM radio band, the MW and LW keys call up the medium- and longwave ranges, and the SW key calls up the shortwave range. With the **Meter** key followed by a numeric key, the shortwave broadcast bands can be accessed directly. The last received frequency in each bradcast band is stored, so that there is an additional frequency memory, in addition to the nine frequency memories. To store the received frequency, press **M** and the memory location number; a stored frequency is called up directly by pressing the corresponding numeric key. To access a frequency, first the **FREQ** key must be pressed, then the frequency is entered and confirmed with ENTER; you can continue tuning with the rotary tuning knob. AUTOSCAN UP/DOWN activates an automatic station scan, which stops as soon as a station with sufficient signal strength is tuned. Touching the UP/DOWN keys again stops the scan or continues the station search. With the SSB ON/OFF switch, the BFO can be activated to receive [[CW]] or [[SSB]] transmissions, for example from radio amateurs; ECSS reception (i.e. receiving an AM shortwave station in SSB mode tubed to zero beat) is difficult due to low frequency stability and wide tuning steps. A ferrite antenna for long and mediumwave reception is built in. For VHF and shortwave reception, in addition to the built-in telescopic antenna an external antenna can be connected. With the built-in digital clock, a SLEEP timer can be programmed for 90 to 10 minutes until the set is switched off, and the radio can also be used as an alarm clock. ===== Technical principle ===== Double conversion, microprocessor control with PLL synthesis circuit. ==== Components ==== The set is equipped with semiconductors. ===== Technical documentation ===== ==== Development ==== {{gallery>:images?sangeas-ats818*.jpg&0&80x80&lightbox&showtitle&titlesort}} ==== Further information ==== * [[https://www.radiomuseum.org/r/sangean_ats_818.html|Sangean ATS-818 on the website of www.radiomuseum.org]]