Shortwave / Air Attack Alarm Receiver E - 646
überarbeitet am 1.9.2010
Zellweger Uster E-646 - probably the last Swiss made shortwave receiver
The Zellweger Uster receiver E-646 has been introduced as alarm receiver
to be used with the air attack alarm network in connection with the air attack alarm
Some receivers carrying a sticker "K" on the frontpanel are equipped with an additional circuit board which will activate the set on calls on all GR group addresses and all "Rufadressen" A - H for testing purposes.
In contrast to the prototype, the speaker grill has been
moved to the left part of the frontpanel. In the upper row of controls, You find the
modes switch to activate A3/A3JU and A3JO as well es the selective call modes RN (with
short monitor periods and low power consumption and RK with continuous monitoring
for coded transmissions, four decadic switches to select the reception frequency from
2'000 - 11'999 kHz and the "Rufadressen" switch.
The receiver E-646 can be powered from an external mains power supply, four ALN 6135-265-1751
7,5 Volt - batteries or by use of an adaptor 16 UM-1 mono cell batteries at 1,5 Volts each.
In a accessory aerial bag, You find everything to construct a long wire antenna to a 6 m mast, a 33 m coaxial cable to connect the antenna to the receiver and - as usual in Swiss Army equipment nearly everything to erect the antenna, even a hammer to put the tent pegs into the ground and a weight, which can be used the throw an antenna wire up on a tree or a building.
The air attack service on fixed shortwave frequencies with it's unique selective
call system is not active anymore, the receiver can be used a a decent shortwave
receiver to monitor Your favourite international shortwave broadcasters. It's
well suited for fixed frequency operation, scanning throug a shortwave band is
cumbersome as the set has only decadic frequency switches and no tuning knob.
The set comes without electronic frequency memories and all the goodies to improve
reception under dufficult conditions as switchable I.F. bandwidths, notch filter,
variable AGC speeds and so on.
d: Empfangsanlage E-646 Benutzerhandbuch, Zellweger, Uster
© Martin Bösch 24.7.2009 / 3.9.2010