Upgrading GE Rangr HF, VHF Wideband Radios

With MX-465P CTCSS Encoder / Decoder - Legacy Conversion

    Here's how to convert GE Rangr radios for 'frequency agile' use on 10, 6, and 2 meters, or for 440 Mhz.   Links to some service manuals are included.   Review these instructions before starting.  Don't attempt it if you don't feel that you can accomplish it satisfactorily or safely.

    The conversion is disciplined, but not difficult.  Once done, you'll have a 100 watt, high quality FM radio of which you can be proud.

    a) General Conversion Information - Schematic

     If you are converting the Rangr model for use on the ham bands, you need the  proper 'split'. Please review these instructions before you start.  E-mail me with questions.

    The external M/P replaces the frequency selection functions of the Rangr's internal M/P.  The leads connecting to the Rangr's frequency synthesizer will be 'disconnected.  In turn, the external M/P 'channels' the PLL for receive and transmit, ana seamlessly manages the CTCSS and wideband functions.

    The conversion involves drilling one hole in the front the Rangr, making the interface connections with a 25 pair shielded (DB-25) cable and with separate power and ground leads fed through the conventional connector mounting. 

Be sure to follow safe CMOS handling procedures.  Never use a soldering gun.   Use a grounded soldering iron.

Note: Even though this conversion will not affect the Rangr's 'spectral purity', the FCC's 'type acceptance' was voided when the radio was modified to accept the frequency agile controller so it can never again be used to transmit on non-amateur frequencies.

b) Powering Considerations

    The fused low current 12 VDC lead (say, from your car's ignition switch) that runs to pin 19 on  P / J-801 can be brought to the control head and activated by a switch on the volume control.  This switched 12 VDC source will also be needed for the new M/P board.   If this powering technique is used, then no other leads within P / J-801 or the DB-25 cable are required.

    Another option is using a small  remote power relay in the Rangr, permitting the removal of the control head when not in use. Placing a ground on pin 17 of the DB-25 cable will operate the relay and provide power to both the Rangr (on J-801, pin 19) and to the Control Head (on pin 3 of the DB-25 cable).   These radios draw considerable current on receive and can easily render a car - whose battery is not charging - incapable of starting in short order.

c) Conversion Steps


Note: A convenient place to pick up these leads is on strip resistor Rx702, a 4 unit 5VDC 'pull up' device.  Before soldering, verify that you have the proper resistor by using your meter to check it against the respective M/P pin. 
Note: Place the shield ground wire under a nearby screw so that the shield is grounded - required for the microphone and CTCSS leads.
Note: Place 2 ferrite beads as shown on those leads requiring them.

d) Constructing The Control Head and Interfacing With the Rangr 

   You'll have to build up a control head.  A large Radio Shack plastic enclosure works perfectly as it can house the P/C board, the keypad, LCD, the volume control (with an OFF / ON switch), a mike jack and even a small speaker.  A 'connectorized' control head may be used with several radios (of the same or different frequency) if the pin assignment convention is the same for each.  Since the new M/P uses flash memory, it's easy to change the radio interface.

    Note: You may program channels used in any of these radios into their respective 'banks'.  There are 5 banks of 20 channels each.

e) Preliminary Tests

    Before applying power, check all connections.  A  test table shows the resistances and (under power) the voltages at each of the DB-25 connector pins.

    Make the resistance tests from the chassis to each of the pins in the DB-25 connector.  They should all be close.  Correct, as needed. Apply power to the Rangr by grounding the low current power relay DB-25 pin 17 and measure the voltages.  When done, remove the ground from pin 17.

f) Construct the Control Head  - 'End-to-End' Testing

    Build the control head  and make the 30 gauge wire connections.  Then, connect the control head to the DB-25 cable.  Using your meter, verify end-to-end continuity of each lead from the M/P itself to the Rangr chassis.  Resolve any discrepancies.

g) Verifying Reception

h) Adjusting the Wideband VCO - 2 Meter - High Split Model

          The VCO on the Rangr High Split (150 - 174 Mhz) will need to be adjusted to satisfactorily cover the 2 meter ham band.

         First, locate TP-201 for the adjustment of the VCO's.  It's under the white 'factory adjustment' paper cover on the VCO board in the rear of the radio.  

        Set the frequency to 148.000 and adjust CV-201 for a reading on 7.0 volts on the meter.

        Key the transmitter and adjust  CV-202 for as close to 7.0 volts as you can get it.  With the one Rangr VHF high split that I've converted, the best that I could do was 5.0 volts, and this was with CV-202 at the bottom of its rotation.  Even with this extreme adjustment, the reading at 144.000 Mhz was 3.6 VDC, so there should not be any problems transmitting within the 2 meter ham band as the transmit VCO is well within the recommended 'lock points'. 

    Using your frequency counter, key the radio and adjust the reference oscillator right on frequency.

i) Adjusting the Wideband VCO - 2 Meter - Low Split Model

      No VCO adjustments should be required on the low split model.  The software in the M/P will select the proper split within the VCO.

    m)  6 Meter Rangr's

    For 6 meter Rangr conversions, additional work is required on the VCO's and on the PA stage.  Click here for more information.

j) Verifying Transmission

Crucial Note - Place the fuse right at the car battery.  This way, a ground on the power cable running elsewhere in the car will not burn up your car, or cause even more severe consequences!  For Rangr's running close to 100 watts, use a 25 to 30 amp fuse.   For Rangr's set to 45 to 60 watts, use a 15 to 20 amp unit.  Don't omit the fuse as a failure within the Rangr or momentarily reversing the power leads will destroy your investment and hard work.

k) CTCSS Testing

    Turn on the Rangr and select a CTCSS tone.    If you have another radio (like a hand held) with CTCSS capability, transmit with the same CTCSS tone selected and verify that the Tone detected LED lights.  Next, transmit with the Rangr and set the tone level on the CTCSS board so that it activates your hand held's receiver (set to break the squelch when the correct CTCSS tone is received). 

   Note: I did not have to adjust the Rangr's internal CG (CTCSS) Deviation Control (RV-604)

Connection Table - Leads Requiring Ferrite Beads Shown in Bold.


Rangr Connection Points &  Connector Pins

 M/P Board Pins

Function / Comments

On / Off J-801 Connector - Pin 26 - 17       None

  Low Power Relay 

Ground J-801 Connector - Pin 5 -  see text MAIN Pin 9

Common Ground

+13 VDC PowerSwitched Relay Connection
(see powering considerations)
23NoneM/P Board Power
SPI - Enable IC-704 - Pin 13 (M/P Board)
Attach to RX-702 (see text)
2 15 PLL - Pin 1 PLL Enable
SPI - Clock IC-704 - Pin 9  (M/P Board) 
Attach to RX-702 (see text)
2 13 PLL - Pin 2 PLL Clock
SPI - Data IC-704 - Pin 5  (M/P Board) 
Attach to RX-702 (see text) 
2 10 PLL - Pin 3 PLL Data
Transmit J-801 Connector - Pin 11 2 1 PLL - Pin 4


COR (CAS) J-801 Connector - Pin 12 - 5 MAIN - Pin 1 5.1 volt zener 
Mike High J-801 Connector - Pin 9 2 9 None

Mike Hot Lead

Mike Low J-801 Connector - Pin 5 -  see text None

Common Ground

Speaker J-801 Connector - Pin 18 - 19 None No GND!
Speaker J-801 Connector - Pin 20 - 20 None No GND!
Vol / Squ High J-801 Connector - Pin 7 - 25 None

Vol / Squelch

Vol / Squ Low J-801 Connector - Pin 6 - see text  None

10K Control

Vol - Center  J-801 Connector - Pin 8 - 4 None

10K Control

Sql - Center  J-801 Connector - Pin 15 - 8 None


IC-601 / 4B - Pin 5 (see text) 2 18 Tones Pin 1 Transmit CTCSS
Chan Change IC-704 - Pin 33  (M/P Board) 
Attach to RX-702 (see text)  
2 14 MAIN Pin 6 PLL Lock & Wideband
 J-603 - Pin 1 or J-607 Pin 1(see text) 2
Tones Pin 2  Receive CTCSS
 TMT OVER  IC-704 - Pin 32  (M/P Board)  2 11 JP10 - Pin 2  Transmit Override
LOCK (PLL)IC-704 - Pin 1  (M/P Board)26JP10 - Pin 1PLL LOCK
-No Connection-23-Reserved
-No Connection-24-Reserved

Test Table - Resistance to Ground and Voltage Tests for 6 Meter and 2 Meter Rangr's.  The 10 Meter and 440 Mhz Rangr have not yet been converted or documented.

   Note: Ground Pin 17 for Voltage Tests.

Pin # Function  6  Mtr
6 Mtr
440 M
440 M
2 Mtr
2 Mtr
1 Radio PTT Inf 6.16Inf 6.18PTT Lead to Rangr
2 CTCSS IN 9.9K 4.5.96K 3.3CTCSS From Radio to the MX-465 Chip 
3  M/P Board Power 11K 13 18K 1313 V Power to External M/P
4 Volume Center Inf -Inf -Volume Control
5 COR (CAS) 11.12K 911.25K 9.08Ensure 5.1 Volt Zener Present on M/P Board
6 Lock PLL  Inf  3.62 Inf   3.62   Optional Transmitter Forced Key
7 Ground 0 -0 -Chassis Ground
8 Squelch Center Inf -Inf -Squelch Control
9 Mike High 2.52K 92.6K 9.09Mike Input to Rangr
10 SPI-Data 10.54K 510.55K 5Serial PLL Data Connection
11 TX Override   Inf 2.70 Inf   2.74  Optional Transmitter Forced Key
12Ground0-0-Chassis Ground
13 SPI-Clock 11.51K 510.59K 5Serial PLL Clock Connection
14 Channel Change 10.55K 510.56K 5Enables Wideband / Fast PLL Lock
15 SPI-Enable 10.60K 510.53K 5Enable Lead for Radio PLL Chip
16 Ground 0 -0 -Chassis Ground
17 On / OFF Switch Inf 13Inf 13Activates (Fused) Low Current Relay
18 CTCSS IN 11.16K 7.191 M 3CTCSS Lead from MX-465 to Radio
19 Speaker 2.6 K 6.68Inf 6.64Don't Ground
20 Speaker 3.3 M 6.682.5K 6.66Don't Ground
21 Ground 0 -0 -Chassis Ground
22 Ground 0 -0 -Chassis Ground
25 Vol / Squelch High 2.2K 4.52.19K 4.55'Hot' Connection for Volume / Squelch Controls

       G.E.and the product names Phoenix, Delta, Rangr are trademarks of Ericsson General Electric Mobile Communications.

DISCLAIMER - If you follow the steps outlined herein, you do so at your own risk. I cannot, nor will not, be responsible for any possible damage to radio equipment, personal property, to yourself or to others caused by modifications that you may make to the radio as a result of your reading this.

The M/P controls TRANSMITTING and receiving on many frequencies, suitable for a wide range of HF, VHF and UHF needs. In the USA, TRANSMIT operation requires a license issued by the FCC  for the class of operation intended.  Amateur radio licensees must maintain strict control over their equipment, preventing unlicensed operation within or outside of the amateur bands.

Copyright 2010 - K3JLS