The Johnson Viking Ranger
by Greg Latta, AA8V

Main Page and Exterior Photos

Ranger Front

Johnson Viking Ranger Pages:
 Johnson Viking Ranger - Main Page and Exterior Photos  Alignment
 Interior Photos of the Restored 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!

Introduction and Historical Background:
On the evening of November 1st, 2013 I was on the 80m band with my 2E26/813 transmitter and I wound up working W3PH, Paul Heller, in Deep Creek Lake, MD. During the QSO I mentioned to Paul that I did a lot of building with vacuum tubes. Paul then mentioned that he had a Johnson Viking Ranger transmitter that he was willing to give me for free if I wanted it. He had purchased it at a hamfest some 30 years ago with the intention of restoring it, but had never gotten to it. It had been sitting in a plastic bag in his shed all those years. After a couple of e-mails Paul brought the Ranger to my house two days later, and on November 3rd, 2013 I was the proud owner of a rather sorry looking Viking Ranger. It was in terrible shape and full of sawdust and mouse droppings, but the mice had simply moved in and hadn't eaten any of the rig. With a lot of work it looked like it could be cleaned up and put back on the air.

The photos below and on the other pages show the end results of six months of painstaking restoration work. The transmitter went back on the air Wednesday, June 11th, 2014. I made the first QSO with crystal control and then switched to VFO control from my external digital VFO. On June 22nd, 2014 I made the first QSO on AM, and reports have been that the audio sounds great. I now have the Ranger on the air on a regular basis. It sounds great, looks great, and was well worth all of the time I spent working on it. The Ranger rides again!

About The Johnson Viking Ranger:
The Johnson Viking Ranger was THE rig to have if you were on AM phone in the1950s. It was capable of 75 watts input on CW and 65 watts input on AM, could operate on all bands from 160m through 10m, and had a built in VFO. The Ranger was plate modulated, unlike many of the wimpy, carrier controlled screen modulated transmitters of the time. It had a robust, choke input power supply and a powerful modulator that could put out more than enough power to fully modulate the single 6146 final amplifier.

The RF tube lineup in my Ranger consists of the following:
6AU6 VFO
0A2 VFO voltage regulator
6CL6 VFO buffer/multiplier or crystal oscillator
6CL6 buffer/multiplier/driver
6146 final amplifier
6AQ5 clamp tube

The AF tube lineup in my Ranger consists of the following:
12AX7 speech amplifier
12AU7 modulator driver
1614 (6L6GC) modulators

The power supply and keying tube lineup in my Ranger consists of:
6AL5 bias/keying supply rectifier
12AU7 timed sequence keying
6AX5 300V supply rectifier
5R4 500V supply regulator

There are three versions of the Ranger. The first Ranger came out in 1954 and did not have the timed sequence keying. The next (standard) model came out in 1955 and added timed sequence keying. It was followed in 1961 by the Ranger 2 which added the 6m band to the transmitter. The Ranger was available either in kit form or as a factory assembled unit. My Ranger is the standard model, since it contains timed sequence keying but does not have the gray coloring scheme of the Ranger II. It was factory assembled because rivets were used extensively throughout to fasten tube sockets and other components to the chassis.

There is no doubt that the first two models look a whole lot better than the Ranger 2. I find their brown and maroon color scheme much more appealing than the grey color scheme used on the Ranger 2. Though the meter on the Ranger 2 is easier to read, the meter on the earlier Rangers is more attractive.

Exterior Photos of the Restored Transmitter:

Scroll Down or Select A Link Below:
 Front View
 Rear View
 Front View Without Cabinet
 Rear View Without Cabinet
 Left Side View Without Cabinet
 Right Side View Without Cabinet


 
Front View:
This is a front view of the restored transmitter. The front panel still shows some battle scars, which gives it character. After all, this transmitter is almost 60 years old!

The white knob inserts were turned from white acetal rod on my lathe and press fitted in place, since most of the original inserts were missing. The cover for the crystal socket was missing, which is a very common occurrence. A special extender plug with an RCA connector was fashioned so that a VFO signal from a modern digital VFO could be fed into the XT1 socket. The extender can be removed if crystal operation is desired. This can be seen third from the left in the bottom row of knobs.

For some reason the inner semi-circle of the clear plastic frequency scale was cut out, though this is hard to see in the photo. I painted the exposed edge flat black to prevent light from escaping and producing glare.

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Rear View:
The cabinet of the transmitter was a real mess. Someone had painted it dark sky blue. The paint was peeling and chipping off, and it looked terrible. Paint stripper was used to remove all of the paint on the cabinet, right down to the bare metal.

There was no hope of duplicating the original cabinet color, so I decided to paint the cabinet a shade of grey that matched the front panel. This was obtained by mixing 2 parts gloss black Rustoleum (High Performance Protective Enamel V7579) to 1 part gloss white Rustoleum (High Performance Protective Enamel V7592). The cabinet was first airbrushed with Rustoleum Professional rusty metal primer (7569), and then airbrushed with several coats of the final grey.
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 Ranger Rear
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Front View Without Cabinet:
In this photo of the front panel, the cabinet has been removed. The power transformer is visible at the left rear, and the VFO cabinet can be seen behind the front panel in the middle.
 Front View Without Cabinet
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Rear View Without Cabinet:
In this rear view of the transmitter, the large "transformer" on the left is actually the plate power supply choke, and the actual power transformer is on the right. These were very rusty and they needed a paint job. To paint them, the entire chassis was carefully masked off, and then they were cleaned and airbrushed in place with Rustoleum gloss black enamel. This was a painstaking, time intensive operation but it was well worth the effort.

The final tank coil (front and center) was polished with Q-tips using a metal polishing product called Simichrome. More Q-tips were then used to make sure that no residue remained. The 6146 final is to the right of the tank coil. The tube worked fine and provided full output, so it was not replaced with a new one.

The top of the VFO cabinet (back and center) has several holes for VFO alignment, and these or normally plugged with plastic inserts to keep air and dust out of the VFO interior. The plastic inserts are usually missing after 60 years. The holes in the VFO cabinet were tapped and short screws were fashioned in my machine shop to fit. These can be seen in the photo as the large brass "screws" on the top of the VFO cabinet.

At back left the meter shield can be seen, and at back right the subchassis containing the 6AL5 bias rectifier and 12AU7 keying is visible. The top of the 5R4 rectifier tube can be seen at right center.

 Rear View Without Cabinet
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Left Side View Without Cabinet:
The left side of the chassis contains (left to right) the power transformer, 5R4 and 6AX5 rectifier tubes, and the Operate/Mode switch. The 12AU7 keying tube and 6AL5 keying/bias rectifier are mounted on a small subchassis above the operate switch, at the upper right in the photo.

The buffer/multiplier tank coil, L6, is just visible behind the large 5R4 rectifier tube. The buffer/multiplier tuning capacitor, C7, is behind the 5R4 rectifier, between the rectifier tube and L6, and is not visible in the photo.

If you look just in front of the rectifier tubes, you will see a couple of the rivets used to fasten the tube sockets to the chassis. The use of rivets is an indication that the transmitter was factory assembled, and not a kit.

The vacuum tube rectifiers were eventually replaced with solid state plug in replacements. This significantly lowered the internal temperature of the Ranger. However, the original vacuum tube rectifiers can be plugged back in any time if desired.

 Left Side Without Cabinet
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Right Side View Without Cabinet:
The right side of the chassis contains (from left to right), the meter, modulation transformer, 6L6GC modulator tubes, 6AQ5 clamp tube, and plate power supply choke.

The meter is mounted on the front panel at left in the photo. The rear of the meter is covered to prevent any RF from leaking out through the meter hole. This is an expensive option, but was necessary in the 1950s to keep down television interference (TVI).

The modulation transformer is the small black transformer on the left, and the modulator output tubes are the large tubes at center front. Metal 1614 tubes were originally used in the Ranger, but glass 6L6GC tubes are electrically the same and capable of higher plate dissipation and higher output. My 6L6GC tubes were made by Sovtek. With the 5R4 and 6AX5A rectifier tubes installed (but not the 6146 final), the modulator screen grid dropping resistor R35 was adjusted for a modulator resting current of 83 mA. The modulator was then tested at 1kHz into a 3.75 kohm resistive load connected to the output of the modulation transformer. Under these conditions, the modulator put out 49.3 W before clipping, which is about 2dB more than the 32.5 W watts needed to fully modulate the 6146 at the recommended 65 W input.

Relative to an output of 11 W at 1000 Hz, the modulator output was down 6 dB at 110 Hz and 3500 Hz.

The 6AQ5 clamp tube is the small tube slightly to the right of center, and the tall 160 m plate tank coil is visible behind the 6AQ5 clamp tube. The plate power supply choke LP1, which looks like a transformer, is at the right in the photo. The multi-sectional plate tank coil is just visible at right behind the plate power supply choke, and the top of L6, the buffer/multiplier tank coil, is visible behind the 6L6GC modulator tubes.

 Right Side Without Cabinet
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