====== AEG / Telefunken E 1800 A ======
**VLF - HF Receiver E 1800 A**; manufactured by [[Telefunken|AEG - Telefunken, Ulm]].

There are various existing versions of the E1800 receiver system :
{{tablelayout?colwidth="80px,-,-"}}
|[[E1800]]|E 1800 with mechanical filters, improved front end| |
|[[E1800/3]]|E 1800 with mechanical filters, improved front end| |
|E1800/4|E 1800 with mechanical filters| |
|**[[E1800A]]**|E 1800 with DSP in the second intermediate frequency| |
|[[E800]]|scaled-down version of the E 1800| |

{{:images:telefunken-e1800a.jpg?direct&600|Telefunken E1800A}}
===== Technical data =====
  * [[Principle]]: [[Double conversion superhet]], [[IF]] 40.2 / 200 kHz
  * [[Operation modes]]: [[A1]], [[A3|AM (A3)]], [[A3J|SSB (A3J)]], [[FSK|F1 (FSK)]], [[F3|FM (F3)]]
  * [[frequency range]]: 300 Hz - 30 MHz
  * [[Frequency display]]: [[digital display]], 1 Hz reading accuracy
  * [[Frequency memory]]: 100 memories
  * [[Signal strength indicator]]: LED bar
  * [[Signal Processing]]: [[RF gain]], passband tuning, [[notch]]
  * [[Features]]: LED bar tuning display (centre tuning), remote control; FSK functions.
  * [[Sensitivity]]: [[A3|AM (A3)]]
  * [[Selectivity]]: 26 DSP filters and an additional 16 phase-optimised filters for digital data transmission.

==== Power supply ====
  * [[Mains operation]]: 115 / 230 V
  * [[Batteries]]: 24 V DC

==== Dimensions ====
  * 433 x 132 x 465 mm, 16 kg

==== Accessories ====
  * TZ-1710 Radioteletype demodulator for F7B
  * DE-1710/2 ESB - demodulator for F1B, F1C, F3B, F7B
  * AD-1710 Antenna diversity 

{{:images:telefunken-e1800a-front.jpg?direct&600|Telefunken E 1800 A}}
===== Operation =====
The E 1800 A receiver is housed in a 19" rack mount unit. The A version is the improved version with digital signal processing (DSP) in the second intermediate frequency.

At the top of the front panel there is a row of LED displays.\\ 
Below that, from the left, are the keys for controlling the memory and scan functions, the numeric keypad for direct frequency entry. The operation frequency can be entered directly, with EXE the frequency is called up.

Below the digital frequency display (which shows the working frequency to **1 Hz**) are the keys for storing and memory recall and the tuning knob. To the right of this is the display of the Operation mode (**Demod**) and the bandwidth or shift. The operation mode is displayed here alphanumerically, the IF filter bandwidth in kHz, and the parameters are selected with the knob on the far right if the key above it is set to DEMOD (operating mode) or BANDW (bandwidth).

At the top right are the LED bar displays, the left one can be used to display the signal and the carrier (marked in red), the right one shows the HF or LF signal strength. 

Below this, to the right of the main tuning knob of the monitor speakers, are the rotary controls for volume control (AF Level), then two multifunctional rotary controls and the monitor speaker switch. The keys above the left rotary control activate the function as [[BFO]] or [[RF Gain]], the right rotary control not only selects the Operation mode (DEMOD) and bandwidth (BANDW) as described above, but also, with the keys above it, the [[notch]] filter (NOTCH) to suppress an interfering signal and the [[passband tuning]] (PASSB), with which the IF filter passband curve can be shifted. This is even indicated on the LED chain above.

The main switch is designed as a small On / Standby toggle switch on the far right.

===== Technical principle =====
{{:images:telefunken-e1800a-back.jpg?direct&600|Telefunken E 1800A: back}}

==== Components ====
The set is completely solid state and modular.

==== Development ====
The Telefunken [[E1800]] was launched in 1985 and was soon considered by experts to be the world's best receiver. This was followed by the [[E1800/3]] version with an improved HF front end and, around 1994, the E 1800/A version with digital signal processing in the second intermediate frequency, the IF filters can be programmed in software in this [[DSP]] technology and replaced the mechanical filters on the 200 kHz [[IF]] of the E 1800.

A slimmed-down version of the E1800 is the Telefunken [[E800]].

The receiver exists with different company names on the front panel, from Telefunken, to AEG - Telefunken, DASA, EADS - the company has had different owners over the last twenty years.


{{gallery>:images?telefunken-e1800a*.jpg&0&80x80&lightbox&showtitle&titlesort}}

===== Technical documents =====

==== Further information ====
  * [[https://www.radiomuseum.org/r/telefunken_allwellenempfaenger_e1800.html|Telefunken E 1800 on the website of www.radiomuseum.org]]