The Johnson Viking Ranger
by Greg Latta, AA8V

Schematic Diagrams And Circuit Descriptions

Small Schematic Diagram
Click on the image for a larger view and access to
the individual circuits and schematic diagrams.

Click Here for a very high resolution schematic diagram suitable for printing.
Print this in landscape mode at 600dpi for best results.

Johnson Viking Ranger Pages:
 Johnson Viking Ranger - Main Page and Exterior Photos  Alignment
 Interior Photos of the Transmitter  Modifications
 Restoration  Schematic Diagrams and Circuit Descriptions
 Typical Operating Conditions  Manuals and Advertisements

Important Safety Note: Working on or testing equipment such as the Viking Ranger is extremely dangerous since very high voltages are present when the equipment is turned on, and may even be present when the equipment is turned off and unplugged. If at all possible, do all work with the equipment off and unplugged and be sure that the capacitors are properly discharged before working on the equipment. The operator assumes all risk and liability in such matters! Do not work on this type of equipment unless you are experienced with working around very high voltages!

The Johnson Viking Ranger is a state of the art transmitter from the 1950s. It uses frequency multiplication and is plate modulated, features which are typical of AM phone/CW transmitters from that period.

The Ranger features a built in VFO, but is also capable of crystal controlled operation. Circuits to suppress television interference (TVI) are used extensively throughout the transmitter. The Ranger was built before solid state rectifiers were perfected, so the power supply uses vacuum tube rectifiers exclusively.

The Ranger is an advanced piece of equipment, but its operation can be understood when it is broken down into its individual circuits. To learn how each circuit works you can click on a link in the table below or you can click on the portion of the schematic diagram that you are interested in. Either way will take you to a separate page on that particular circuit.

Very High Resolution Schematic Diagram:
A very high resolution copy of the entire transmitter schematic diagram is available here:

Very High Resolution Schematic Diagram Of The Johnson Viking Ranger

Right click on the link above and use the "Save Link As" or "Save Target As" option to save the file on your hard drive. It is a big file so I ask you to please avoid downloading it more than once if possible.

This was obtained from a product brochure for the Johnson Viking Ranger, and is the most detailed schematic I have been able to produce from that brochure. If viewed with an image viewing program under magnification, or printed on a high quality printer, it is possible to see exactly how the various rotary switches in the Ranger function.

I suggest that you print this schematic out on an 8.5" x 11" piece of paper and keep it next to you as you study the individual circuits. The complete schematic diagram will keep you aware of how the circuits work together as an entire group, while you study each circuit individually. You can also crop the main schematic and print out individual circuits in high resolution and excellent clarity.

Enjoy and 73,
Greg AA8V

Select A Link Below:
 RF Circuits  Audio Circuits
And Operate Switch
 Power Supply And Keyer Circuits
 VFO  First Audio Amplifier  Bias/Keying Power Supply
 Buffer/Crystal Oscillator  Second Audio Amplifier  Low B+ Power Supply
 Multiplier  Audio Driver  High B+ Power Supply
 Final Amplifier  Modulator  Timed Sequence Keying Circuit
 Final Amplifier Tank Circuit  Operate Switch
 AC Power/Control Section
 How Timed Sequence Keying Works
 From Key Up To Key Down To Key Up
 Clamper  Operate Switch - B+ Section  Meter Circuit
     Accessory Socket


Click On Any Part Of The Schematic Diagram Below For Information On That Part Of The Circuit

Schematic Diagram Operate Switch - AC Power/Control Section Operate Switch - B+ Section Accessory Socket Meter Circuit High B+ Power Supply Low B+ Power Supply Bias/Keying Power Supply Timed Sequence Keying Circuit Modulator Audio Driver Second Audio Amplifier First Audio Amplifier Final Amplifier Tank Circuit Clamper Circuit Final Amplifier Buffer/Multiplier Stage Buffer/Crystal Oscillator VFO
Click On Any Part Of The Schematic Diagram Above For Information On That Part Of The Circuit

Click Here for a very high resolution schematic diagram suitable for printing.
Print this in landscape mode at 600dpi for best results.

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