Tube Radio Australia
Bendix MN-26 Restoration Project
This was a Radio Rescue Special.
-
General Description
-
- The MN26 is an aircraft direction finder type superhetrodyne receiver.
There are at least 6 different models of this receiver, the most common being
the MN 26C which tunes 100 - 1500 kHz in 3 bands. The input voltage for this
model is 28 volts dc (5 amps peak) This is one of three I have all had been Hacked up.
The receiver itself was located remotely in the aircraft and operated by
remote control so as to save cockpit space. For a tuning meter the MR57A
is used and the IN4A for left/right homing. The D/F loop (MN20 or MN24)
was located either above or below the aircraft and was hand rotated using
Bowden drive through an MN22A or MN52A control head.
The MN26 was a commercial unit as opposed to one designed specifically
for the military. Although many of these radios were used by the military,
they were eventually replaced by the automatic D/F types in the middle of
WW2, types such as ARN6, ARN7 and BC433G.
The MN26 was a popular receiver after the war as a high performance broadcast
receiver. After the D/F section was removed, what remained was quite a sensitive
8 valve receiver. Published conversions included sawing off the rear end
of the set, mounting it under the driver's seat and hey presto! one had
a super hot receiver for the car.
-
Technical Data
-
- There
was provision for direction finding in other receivers by use of a manual
loop such as the LF version of the ARC 5 and the RA-10B. The AWA AR8 (Australian)
had D/F coils fitted to use with a manual loop.
Band change was by an electric motor and tuning by a flexible drive through
the MN28A control box. Two of my sets were missing these motors I have sonce found one.
The tube line up is as follows:
V1 6K7 Loop
Amp *
V2 6N7 Audio
Osc (48 cycles) *
V3 6N7 Modulator
*
V4,5 6K7 RF Stages
V6 6L7 Mixer
V7 6J5 Osc
V8 6K7 IF
Amp (112.5 kHz)
V9 6J5 BFO
V10 6B8 Audio Amp
V11 6F6 Audio Output
V12 6K7 Compass Amp *
(Functions marked "*" are for compass operation and are not needed for general
reception.)
The
MN26 will take D/F bearings on "Compass", act as a standard receiver on
"Rec Ant" using a short vertical antenna and will also receive stations
with the loop antenna on "Rec Loop".
Being fully remote controlled, few receivers remain in their original
form. The display receiver is fully operational, as intended for aircraft
operations. Check the short Video for a Demo of it working.
Final Radio Display
Please Note you will need Quicktime to play this from your browser click to hear it again
This was a Radio Rescue Special.
-
General Description
- The MN26 is an aircraft direction finder type superhetrodyne receiver. There are at least 6 different models of this receiver, the most common being the MN 26C which tunes 100 - 1500 kHz in 3 bands. The input voltage for this model is 28 volts dc (5 amps peak) This is one of three I have all had been Hacked up.
The receiver itself was located remotely in the aircraft and operated by remote control so as to save cockpit space. For a tuning meter the MR57A is used and the IN4A for left/right homing. The D/F loop (MN20 or MN24) was located either above or below the aircraft and was hand rotated using Bowden drive through an MN22A or MN52A control head.
The MN26 was a commercial unit as opposed to one designed specifically for the military. Although many of these radios were used by the military, they were eventually replaced by the automatic D/F types in the middle of WW2, types such as ARN6, ARN7 and BC433G.
The MN26 was a popular receiver after the war as a high performance broadcast receiver. After the D/F section was removed, what remained was quite a sensitive 8 valve receiver. Published conversions included sawing off the rear end of the set, mounting it under the driver's seat and hey presto! one had a super hot receiver for the car.
Technical Data
- There was provision for direction finding in other receivers by use of a manual loop such as the LF version of the ARC 5 and the RA-10B. The AWA AR8 (Australian) had D/F coils fitted to use with a manual loop.
Band change was by an electric motor and tuning by a flexible drive through the MN28A control box. Two of my sets were missing these motors I have sonce found one.
The tube line up is as follows:
V1 6K7 Loop Amp *
V2 6N7 Audio Osc (48 cycles) *
V3 6N7 Modulator *
V4,5 6K7 RF Stages
V6 6L7 Mixer
V7 6J5 Osc
V8 6K7 IF Amp (112.5 kHz)
V9 6J5 BFO
V10 6B8 Audio Amp
V11 6F6 Audio Output
V12 6K7 Compass Amp *
(Functions marked "*" are for compass operation and are not needed for general reception.)The MN26 will take D/F bearings on "Compass", act as a standard receiver on "Rec Ant" using a short vertical antenna and will also receive stations with the loop antenna on "Rec Loop".
Being fully remote controlled, few receivers remain in their original form. The display receiver is fully operational, as intended for aircraft operations. Check the short Video for a Demo of it working.
Final Radio Display
Please Note you will need Quicktime to play this from your browser click to hear it again