SE-105 / P 5 set / patrol radio set
Zellweger AG, Uster

Swiss Army Communication Sets
Synoptic Table
Army Transceivers
Transceivers SE-1xx
Transceivers SE-2xx
Transceivers SE-3xx
Transceivers SE-4xx
SE-100 / FOX
SE-103 / RTS
SE-104 / P
SE-105 / P5
SE-106 / P5 F
SE-108 / K1
SE-109 / K1A
SE-110 / MAX
SE-112 / M5
SE-113 / T5
varia / copyright
about / contact

überarbeitet am 5.9.2010

The P 5 set constructed by Zellweger, Uster, is the high power variant of the "P Geraet", the patrol radio set.
A very similar set has been in use onboard vehicles (M 5 / SE-112) and onboard a vickers tank (T 5 / SE-113).

Transceiver, receiver I.F. 465 kHz

18 - 24 MHz ,

AM (A3, A2)

pout A3 5 W



powered by a combined LT / HT battery 6 + 126V (Leclanché 1266) or a hand cranked generator,
3,4 m vertical antenna
Reglement Funkgeräte der Infanterie P / P5

The P 5 set (Infantry Patrol set) consists of a transceiver case with a battery compartment (weight 15,4 kg, with the battery 19 kg), a generator case (another 15,4 kg) with the hand cranked generator and spares and a canvas bag (5,7 kg) with material for a long distance antenna.

In the transceiver case, the transmitter section is located at the right and the receiver section at the left side.

The receiver can be powered from a combined LT (1,5V)/ HT (126V) battery or a hand cranked generator; for transmitting, the hand cranked generator must be used under all circumstances, a relay prevents the transmitter section to be be powered from the battery which might be exhausted very soon.
The set switches automatically from receive to transmit mode when You press the push-to-talk button or when You operate the morse key, one second after transmitting the last morse code letter, the SE-105 returns to receive operation.

The operation of the transceiver is easier then to supply it with the necessary voltages:
The huge frequency dial pointer also acts as tuning knob, it does directly operate the main tuning capacitor of the transmitter and receiver sections. Press the two pushbuttons at both sides of the dial pointer to move it, it will lock in 20 kHz steps mechanically. A round thumbwheel lets You detune the set for +/- 50 kHz, to move the dial pointer to another position, set the interpolation tuning knob to zero again. A rotary control "Empfangsnachstellung" permits to shift the receiver's operation frequency +/- 50 - 100 kHz.
As found in other Zellweger sets, the main switch has it's zero / off position in the middle, turn it to the left for telegraphy mode and to the right for telephony mode, the control also acts as volume control.
Use the antenna tuning control to adjust for a maximum reading on the antenna current instrument when the transmit switch is activated; the meter can be switched to indicate the heaters and anode / B+ voltages, too.

The accessories can be stored in a compartment just below the transceiver chassis: the combined LT / HT battery, the headphones, the hand and the throat microphone and the morse key.
With the switch on the microphone on the "on" position, the valves of the transmitter stages are heated continuously, in the "off" position they are switched off and the SE-105 is in "receive" mode only, when You press the push-to-talk button, You have to wait four seconds until You can start speaking.

The generator is integrated in a case very similar to the transceiver case: a voltmeter indicates, when the necessary voltages for operation are okay or if You have to crank with higher speed to generate the heaters / LT voltage of 5,7 V ond the anode / HT voltage of 120 Volts. A rotary switch allows You to reduce anode / B+ voltage from 180 to 90 Volts, the transmitter output power will be reduced to 1 W and You will find turning the crank of the generator a bit easier.

The set's operation range is 3 km in telephony and 5 km in telegraphy mode in not very suited a housing area and up to 180 or 200 km from a optimum location on top of a hill.

A typical "Wireless Radio Patrol" consisted of four men: a corporal (sergeant) acting as group commander, a radio operator, a writer and one person operating the generator. These radio patrols had to march on foot or could ride bicycles.

© 5/2008 Martin Bösch