OLGA PROJECT
by IK0MOZ
Starting from this page it will be the details for the
set construction.
The work has been divided in sections cause the large
number of photos and drawings and to avoid large download time.
Specially for drawings and schematics has been used,
to assure an acceptable readibility, high resolution quality so the download
could be in this case quite slow.
Time by time at the end of each sections will be the
experiences arrived from the "Replicanters"
The main sections are :
RECEIVER
TRANSMITTER
POWER SUPPLY
COMPLETE SET
ACCESSORIES
First release : May 25 2002
Rev A - June 03 - added MKI Diagram
Rev. B - June 13 - Added Drawings R01,02,07,08
Rev C - June 24 : Added MKII receiver photos
The receiver is a supeheterodyne with six valve functions
in three valves, two ECH21 (triode-heptode) and one 6C8G (double triode).
This produced a significant increase in sensivity compared to the former
MKI model using the same number of valves but of different type (6K8G,
6K7G, 6C8G) and with 5 only valves functions.
Well suited for primitive production, it contains few
components and require a minimum of alignment. It covers the range from
3.5 to 16 MHz in two bands. The antenna signal is fed to the mixer via
a simple tuned circuit. After the mixer comes in two IF stages. In a third
stage the IF signal is mixed with the B.F.Oscillator and grid detected.
The BFO is switchable and the volume controll is on cathode circuit of
the first IF stage. The LF signal drives an high impedance headphone.
As said in the Story sections there is also the possibility
to built the LISBETH only.
Olga and Lisbeth side by side (Norwegian
Resistance Museum, Oslo)
The drawing available for this section are :
R01 - Receiver Assy
R02 - Chassis
R04 -
R05 -
R06 -
R07 - IF Transf. and BFO coil
R08 - Coil Pack
A view from the rear side of the receiver
(LA3BI)
For the schematics
The receiver seen from the components
side - To the right the COIL PACK (LA3BI)
MKII type - Components side (Magne Lein - Norway)
The MKII tipe using the ECH 21 valves (Magne Lein - Norway)
Grey Grenn Radio PARASET page OLGA Main page