[ARC5] Electronic Specialty "RANGER" Light Air Set

[David Stinson]

Been beating life back into late-1945 light aircraft sets
produced by the "Ranger Aircraft Radio Division"
of Electronic Specialty Company.  
The transmitter is a model 209 and 
the receiver is a model 120.
The transmitter will also match-up with the E.S. Ranger 
model 116 receiver.

I've got them on-the-air and worked Texas, Miss.
and Alabama this morning with good reports for 
10 watts out.  Here is a crummy photo of the set
in a temporary lash-up:

http://home.netcom.com/~arc5/rangerset.jpg

I temporarily replaced the transmitter antenna connector
until I can get the correct one.
The 209 transmitter has an internal vibrator supply
with a pair of 6X5 rectifiers which powers the entire set.  
Antenna and power switching is in the transmitter 
and connected to the receiver via the Jones plugs
 on the front of the transmitter and rear of the receiver.  

Transmitter is a 12A6 crystal oscillator driving an 807 PA
running 400 VDC with a parr. tuned tank and coil tap 
to match the antenna.
Haven't tried to tweek the output for exactly 50 ohms.
A 12SL7 mic amplifier drives P-P 6V6 plate modulators.
There is also a 12J5 screen clamp tube to protect 
the 807 from loss of drive.  

I had two of the Ranger 120 recievers, one with 
and one without a phone jack on the front panel.
I kept the one with the jack.  
The 120 is an LF "Range" receiver 
with one of my converters installed:

http://home.netcom.com/~arc5/Imprvconverter.jpg
http://home.netcom.com/~arc5/CNVTRINSTL.JPG

Note the increase in the supply voltage dropping 
resistor in the converter.  The original was "too hot"
for this set and dropping the supply voltage fixed it.
Might be a good place for an RF Gain control.

The rear of the reciever has an 8-pin female Jones plug which
matches that on the transmitter.  There is also a four-pin male
Jones which is intended to connect a mic/phones headset.
Here are the connections:

Transmitter
1- Ground
2- A+ out to rcvr 
3- B+ out to rcvr (dropping resistor supplies 200 V)
4- Switched to ground to turn set "On."
5- Mic Audio
6- PTT to Grnd
7- Ant. out to rcvr
8- (Sidetone?  Not used here)

Receiver  (8-pin)
1- Ground
2- A+ in
3- B+ in
4- Switches to ground from Off/On Vol. 
5- to 4-pin connector (mic audio)
6- to 4-pin connector (ptt)
7- Ant. in
8- (not used here)

Receiver 4-pin
1- Ground
2- Audio out
3- Mic audio    
4- PTT