aeg telefunken e1800a receiver racal ra-3701 ra-3791 ra-1792 harris RF590 watkins johnson 8711 rohde schwarz ek070 radio




The back panel is built up using separate modules which slide and plug into a mother board situated within the receiver behind the front panel. All connections are made to each module via a multiway euro type connector. This includes RF signals which connect using co-axial connectors.

Several of the modules fitted to the E1800A are common to the E1800/3 series

The following is a cut down description of each of the modules fitted to this example


This is the front end incorporating 1st and 2nd mixers.

There are two antenna N type input connectors. 0.01 to 1.6MHz and 1.6 to 30MHz. An on board option link however can be set to connect BU1 (10K to 1.6M)Hz, as the main input for all signals, from 0.01 to 30MHz.

1st IF is 42.2MHz. 2nd IF is 200KHz.

1st mixer post roofing filter is 10KHz bandwidth.


The analogue interface accepts 200KHz IF signal from HT1710, converts to digital and passes this data to the DP1800. After processing in the DP1800, the AI1800 converts the digital data back to audio for distribution via the line or speaker.

Speaker connection is via the main chassis BU602, 3 pin miniature Lemo connector.


Contains 7 x NEC digital signal processors and supporting hardware, which among other functions, calculate signal strength and provide AGC, carry out IF filtering, passband tuning, notch filtering and demodulation. The digital audio is returned back to AI1800 for conversion back to audio frequency signals.


Synthesizer oscillator, generates all the local oscillator signals required for the receiver's mixers.


The BITE processor


Main power supply. An efficient switching power supply that stays cool during use. It is very well screened and there are no fans or exterior cooling requirements other than convection air cooling through the main receiver chassis.

Front Panel

Showing the four front panel rack fixing holes.

The two strong handles can easily support the weight of this receiver.



More will be added to these pages as my time permits
If you have any questions or comments about this website, send me an email. I will read all but I can't guarantee that I'll reply to all. This is just a hobby site and my normal days work takes priority
I am not a trader or professional buyer or seller of these great bits of kit. It's just a hobby of mine to collect, play with, digest technical information and then either keep safe or pass on to another equally dedicated individual who will take care of these wonderfully engineered machines!
This website is not affiliated to any manufacture or model and the information contained is of my own work and as such, measurements and figures quoted are for reference only and are not intended to discriminate any individual product
2018 by Andrew Cygan