This receiver was first released in 1938 by Telefunken and was considered the "next generation" of high accuracy monitoring receivers. It was from a series of six similar receivers that covered a wide frequency spectrum: Fu. H. E. a (72 - 887 KHz), Fu. H. E. b (857 KHz - 3.75 MHz), Fu. H. E. c (3.75 - 25 MHz), Fu. H. E. d (24.28 - 61.9 MHz), Fu. H. E. e (60 - 145 MHz), Fu. H. E. f. (145 - 305 MHz). Some of these receivers were manufactured by Lorenz and others by Telefunken. Because of their multi-colored frequency scale, they are known as "Peacock Receivers".

This is a general-purpose, portable, up-to-date (for 1940) super-heterodyne receiver of die-cast light alloy and sheet aluminum elaborately designed. It operates on an intermediate frequency of 1875 KHz and consists of two HF amplification stages, frequency changer, separate oscillator, three IF stages, amplifying grid detector, output tube and heterodyne oscillator. A rotating turret carries the HF and oscillator tank circuits - 4 sets of 4 tank circuits each; inductance adjustment is by threaded iron cores in the antenna and HF plate coils and by a copper slug in the oscillator coils; parallel trimming is by variable ceramic capacitors and oscillator padding by fixed tubular ceramics.

Circuits are tuned by a 4-gang variable capacitor of die-cast construction with ball bearings and ceramic insulation. The heterodyne oscillator is controlled by a three-position switch - one for "off" and other two giving notes of 1000 KHz below and 1000 KHz above the null point. A 900 KHz filter that permits CW signals to be received, in spite of interference, consists of a tuning iron core choke in the 2nd detector plate circuit that can be inserted by switch "Tonsieb".

AVC is extremely effective, rise out of output being 2 DB between 5 microvolts and 50 millivolts. The first IF coupling comprises a pair of tuned circuits coupled through a quartz crystal and a reactive link having common inductance and a small capacitance. A small 2-gang variable capacitor de-tunes the two circuits in opposite directions. The receiver has ample total gain; when tested on bandwidth of 10 KHz using a dummy load of 100 Ohms, the modulated input (30% modulated) for signal/noise ratio or 20 DB varied between 10 and 16 microvolts. The corresponding figure on a narrow bandwidth and without the filter is 4 to 7 microvolts or approximately 1 microvolt on CW.