| G4HTZ |
Rating:      |
2021-04-28 | |
| VIKING overhauled |
Time Owned: 3 to 6 months. |
I am in the Uk and saw a Viking 2 for sale on eBay In the USA …for some reason I bought it and had it shipped over to England.
It looked in very good condition …changed the usual power supply and bias caps …it was producing 120w carrier …but no audio ….further investigation showed someone had modified it to a 12AX7 and a 6C4 …and mis wired it in the process of doing it ….also the driver audio transformer was open circuit.
Completely re built the audio stage and put in a Hammond 124B transformer which I had to get from mouser in USA ..it arrived in 4 days …installed transformer and now loads of audio ….worked a couple of stations and good audio reports ….this was my 1st go at restoring a valve transmitter…
I can recommend the D-lab videos on you tube if your thinking of restoring one yourself …
Steve G4HTZ |
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| N8FVJ |
Rating:      |
2020-11-27 | |
| It does not get Better for AM use |
Time Owned: 0 to 3 months. |
The Johnson Viking II is likely the best AM transmitter ever made. The Viking I is about the same, but uses the more rare 4D32 RF tube. The Viking II uses a pair of 6146 tubes that will be available for years into the future.
Every operating parameter is tunable thus it basically operates perfect. It produces 100 watts carrier and will fully modulate to 100%. Weight is a reasonable 70 lbs where as the Collins 32V series and Heathkit DX-100 is 110 lbs.
The only modification is the 12AX7 to 6C4 speech amp replacing the two 6AU6 tubes. Later Johnson transmitters uses the 12AX7 into a low gain 12AU7. The 6C4 is 1/2 a 12AU7 and appears sufficient. Other mod is to replace the light weight driver transformer with a Hammond 125B. Frankly, I get enough drive and audio quality from the stock driver transformer.
The Johnson Viking II does not have a built-in VFO. Just a few frequencies are used on AM being 3880, 3885, 7190 and 14286 kHz. I prefer using crystals vs a drifty VFO. So, no inconvenience without a VFO and you do not need a frequency counter to check and maintain your transmit frequency.
The 5R4 high voltage tubes are at the limit voltage wise. I had a few tube internal arc overs upon key down. The newer 5R4GB do not have much filament to plate spacing due to the filament wraps around the top mica. I would use the 5R4WGB, but the wide base is very tight. Using a 1/4" spacer, the sockets can be lowered and moved slightly apart for the wide 5R4WGB bases. Or, use a 2800 volt rated 5R4 with the filament wire hanger that doubles the plate to filament spacing. This transmitter is highly recommended. |
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| W5GW |
Rating:      |
2011-07-26 | |
| My third one |
Time Owned: more than 12 months. |
My first one I used on CW almost exclusively. Never had an issue with it or the companion VFO. Like a dummy I sold it.
My second one I got a few years ago. It is very good but has a chirp on CW I'm still trying to tame. Someone had replaced the low voltage 15 Mfd caps with 50 Mfd (probably thinking more is better). I took those out and replaced with 15 MFd and chirp improved considerably, but still a bit there.
My third one I got about a week ago. It came with the grid-block keying add-on that Johnson sold for the Viking Is, IIs and early Rangers. I replaced the low voltage and bias caps, finals, and cleaned it up. No chirps on CW and audio with a D-104 sounds pretty good. Previous owner had overhauled the modulator and it is really nice, no hum whatsoever and a good frequency response. Both Vikings I have now produce 110 Watts on CW or 90 Watts on AM on 40 meters. Keep grid drive below 5 ma for better tube life and maybe only load up to only 100 W CW and 80 W on AM for a more conservative treatment of this old iron. |
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| KG8LB |
Rating:      |
2011-03-19 | |
| Solid performer |
Time Owned: more than 12 months. |
I have owned a few of these over the years and have always been pleased with the Vikings, both the 1 and 2 series. Solidly built, well engineered and built from very high quality commercial grade components . Heavy duty ceramic sockets and switches along with a unique roller inductor that is gear coupled to an air variable in the output tank. A bit more to the learning curve in this one compared to later EF Johnson transmitters but still easy to operate. Some folks consider the external VFO a drawback but not really need be. There are many fine VFOs that will work with the Viking. As a side note to those who expressed difficulty from the VFO being keyed by an empty key jack : The manual details how to use pin 8 (IIRC) on the accessory socket to key the VFO when going to "Transmit" in the phone mode.This will allow turn the VFO into standby while receiving and eliminate the VFO tone from your receiver. Spotting is then accomplished by simply moving the mode switch to "CW" . The PTT mod is quite simple. A couple variants use rectified 6.3 volts from the filament circuit and a 6VDC DpSt relay across the plate switch. A diode voltage doubler on the Filament line can provide 12VDC in order to use a similar relay with a more easily sourced 12VDC coil. Another source of 12VDC would use a wall wart supply mounted under the chassis and tapped in to the 110 VAC switched AC supply. Avoid using AC on the PTT line to prevent hum pick up.
Audio mods abound for those who care to experiment a bit and taylor the audio as they like. All in all a fine, easy to use and service transmitter. |
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| N8CMQ |
Rating:     |
2011-02-06 | |
| Nice CW annd AM transmitter |
Time Owned: more than 12 months. |
I owned my Viking II for two years, then the modulation transformer shorted and at the time, I could not find a replacement, so I sold it.
I did have a chirp problem when using the VFO, but it depended on how you keyed the VFO or transmitter. When the VFO was free running and you keyed the transmitter, there was no chirp. There was a small tone heard in the receiver though, but I used it as the "tune" signal, and you only heard it in the transmit mode.
Only good memories for this tank of a transmitter! |
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| AC0FA |
Rating:      |
2009-05-11 | |
| Plate Modulated |
Time Owned: more than 12 months. |
The Johnson Viking II is a heavy duty cycle plate modulated am transmitter. It puts out
400W peak to peak on AM Phone. It has a very nice TX audio when on the air.
The Johnson engineers designed the original modulation transformer to operate from
300 to 3000 khz. This is where the power in my voice is also.
It has a very rugged design for operators who can talk for 10 minutes straight in a round table qso(I am not kidding) it dosen't over heat.
I the best audio results come from adding more capacitance to the driver tubes in the audio chain. I also find the 6C4 and 6AH6 tubes to perform better than the originals.
Early designers were also limited by the size of the capacitors. More capacitance is better. Improving the bottom end and giving that full body audio sound.
I really enjoy using my Viking II it will tune a Gap Titan vertical or a 80M horizontal loop.
I was also impressed with the precision of the external 122 vfo. It is extremely accurate for a rig of its age without much drift. Once it settled down.
The only things I would change would be on a bone stock Viking you need to flip the plate switch to talk.
I would much rather use the key on the mike. There are mods on the internet that are very easy to do.
The other nit i would pick on a bone stock Viking II would be the goofy button connector for the mike.
The mikes that originaly used the button connectors had diferent impedance requirments than my Astatic D-104 I really prefer the 1/4" female plug.
The CW jack will short to ground and continously transmit key down when there is no code key plugged in to the CW jack.
There may be a reason for this but it is not helpful to me on phone.
All in all a very easy rig to work on. Well laid out. Plenty of room. Good rf shielding copper cabinets. The owners manual includes assembly instructions. diagrams and Pictures. You can actually trace every connection on the rig. If you wanted to.
I give it a 5
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Earlier 5-star review posted by AC0FA on 2008-02-07
I picked up a Johnson viking II. Recently for less than a tank of gas. I could tell it was the original paint because it was only half there. but thank fully the brown spots showing through were the copper chassis and not actual rust.
I sanded her down with 220 grit and shot her with menards kona brown and battleship grey.
I never thought a country boy like me with construction paper and an exacto knife could get so close to Johnson factory quality.
Well every rig has their story. The viking II seem to have the power supply tubes come loose durring shipping. So pack tubes seperate.
The CW key jack shorts to ground when in CW mode. The Viking will transmit full blast key down with no key in the jack.
Be aware of this before buying from the guy that dosen't know what it does but it lights up when he plugs it in. Yea I bet it lights up!!
I altered mine with electrical tape between the shorting contacts in the key jack.
I ohmed out the iron all was well except the audio driver transformer.
They do seem kind of fragile and the first thing to go.
I found a standard 3:1 audio transformer that was suitable but not center tapped.
I fed current to the audio transformet through a voltage divider network consisting of 2 10k resistors fed at the center with each end feeding an 807 tube socket.
Discovering no modulation I built the speech amplifier section x1 and x2 with a 12ax7 and a 6c4.
Adding capacitance here and there mainly because capacitors are higher voltage and much smaller now than in 1955. more capacitance means more bottom end and less distortion.
Upon very close examinition I discovered the large roller inductior ganged with the final capacitor. Had a problem.
One of the leaf springs had broken on the roller mechanisin that holds the small shorting wheel to the windings of the inductor.
Intermittent contact on the roller inductor means intermittent loading and unloading of the final not good.
After dis-assembly,repair and conservative use of grease that does conduct electricity.
The Viking II was ready for full power operation.
The modulator came to life.
The old Viking II sounds beautiful on the Hammarlund HQ 129X with the 6khz filter. Excellent audio Full Power. High Quality components.
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| AF9J |
Rating:      |
2008-03-21 | |
| What a Cool Transmitter! |
Time Owned: 3 to 6 months. |
About 13 years ago, I made an abortive attempt (at a previous QTH) to get on AM. It was a mess, due to the Ranger II I owned at the time, causing TVI with Channel 2 TV. Last year, I decided to give AM a whirl again. I didn't have the TVI problems I had years ago, but my FT-897D just didn't cut it (besides, I wanted some cool tube gear, like I used to have in the 80s & early 90s, when I was teenage & 20-something Novice & General). So I progressed to a Hallicrafters SX-96 receiver, for better AM reception. I still have it. The transmitter - well, that was a different story. The Heathkit Cheyenne was OK, but not my cup of tea. The Globe Scout 680 was OK, but I wanted 160m capability (I've had a soft spot for that band, since I was a General in college, in the 80s), and a bit more carrier power for the noisy band conditions that are all too common on 160, 75, & 40m. That's where the Viking II enters the story.
A regional AM swap net that meets on 3885 kHz listed a Viking II for sale one Saturday Morning in November 07. I contacted the seller. The $75 selling price was easy on my budget, so I made the 135 mile trip to pay for, and pick up the radio. My Viking II was loaded with dust. Four holes had been drilled in the front panel (two of which, had BNC connectors in them, that weren't connected to anything), and it hadn't been used since who knows when (the seller had never powered it up). There were the inexplicable mods made to it (such as tapping two 15 ohm 300 watt resistors [hanging in thin air on one lead of each resistor], one filter capacitor that was not connected up on one lead, and the use of a multiturn audio pot for the clamper circuit [THAT threw me for a loop, when I had to set the clamper circuit for the finals]), that had to be straightend out. The old, paper electrolytic capacitors were also replaced. Over the next 4 months, I restored my Viking II as time allowed. It went on the air for the first time in how many years, 3 weeks ago.
What a great transmitter! Mine already has the factory approved PTT mod installed, so it's nice to have PTT (which the Scout lacks). Tune-up is relatively straightforward. I get good audio reports with the Astatic D-104 I use, and with 100W of carrier power, I'm heard much better, than I was heard before (which beats having to get an amp, which the Scout really needed during noisy band conditions).
My Viking II mated up well with the Heathkit VF-1 VFO I have, so I now also have frequency flexibility. SWRwise the Viking II is pretty forgiving, especially since it has a Pi network in it that matches a pretty wide range of loads. It is also relatively easy to work on (unlike most of today's SMT componented rigs). Yep, I'm set for AM. I will say this though, it sure is heavy enough at 75 pounds!
73 & may the modulation be with you,
Ellen - AF9J |
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| W1BKZ |
Rating:      |
2007-01-24 | |
| Great AM/CW XMTR |
Time Owned: more than 12 months. |
| When I got my General class license in 1955, my Dad (W1BBB) bought me the kit and a 3.86 Megacycle XTAL. I put it together and with the aid of a D-104, Hallicrafters S-76, and a dipole, made my first 'phone contact with my "Elmer", W1AVP. Since that moment, I have enjoyed that rig more than any other transmitter (except, of course, my Heath AT-1, which I still have). Really well-built, excellent design, thoughtful layout, and easy to operate. The addition of the 122 VFO really made the Viking a versatile 160-10 transmitter. Mine had stock audio, and I added the Key-click reduction unit, along with a PTT relay. Really nice rig that runs forever. |
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| K7UA |
Rating:     |
2006-07-21 | |
| Heavy Iron |
Time Owned: more than 12 months. |
| I'm giving the Viking II a 4 because mine had the worst key clicks I have ever tried to deal with. Other than that it was great. Built like a tank and about in the same weight class as one! I used mine on 160M when my new fancy rigs didn't include that band. Early 1970's. Lots of knobs to tune. I set up mine with a bunch of crystals to make a simulated VFO for my wife when she got her novice. Just turn the knob and slide up 10 khz. Last time I moved I gave it to a kid next door that was interested in ham radio. It wasn't a very pretty version. Along it's long life someone had done crumby paint job on the front panel. It still worked ok though. |
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| VE3CUI |
Rating:      |
2006-01-18 | |
| What a GREAT Boatanchor Rig!!! |
Time Owned: more than 12 months. |
I sold my Ranger-1 several years ago, & when the opportunity arose for me to buy this Viking II "C-C" transmitter ("C-C" as in "continuous coverage" --- a variant built for the Royal Canadian Air Force, & quite rare to-day) for sixty bucks, I JUMPED at the chance!
What a GREAT radio this is --- built like the cars Detroit made in that same era, i.e. big, beautiful, and like a proverbial tank! I had to snip out a few bypass caps, & increase the size of some coupling caps, in the audio chain to "brighten" the audio, but it took VERY little effort, & the rig sounds like a BC station...in fact, some V2's ended-up as that, i.e. local SW BC stations, in some South American countries!
They are rugged, dependable, easy to work on, but O-SO-HEAVY!!! You & I will be long gone, buit these big boys will still be here, doing what they were designed to do... |
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