Elmer needed for help restoring and modding a Johnson Viking Ranger II

[n7ioh]

I have two Johnson Viking Ranger II transmitters.  One I wish to do some restoring to and get back on the air. It is in much better condition cosmetically than the other.  The other I may also want to get back on the air provided I don't have to take any critical parts off of it to restore the first.  I am pretty good at soldering and doing the mechanical work but not much good at understanding electronic circuits.  This is where I could use some help.  I am wanting to replace many of the old caps and resistors and solid stating the rectifiers along with making a few other improvements including adding a three wire power cord and upgrade the 7027A modulator tubes to the 6550 tubes.  I have downloaded a copy of, The Competition Class, Stock Eliminator Ranger, by Timothy M. Smith, WA1HLR, The TimTron. 
http://www.amwindow.org/tech/htm/rangtron.htm
I am using this as a guide so much of what is in there I will be wanting to do.  In reading the information some of it is not real clear to me.  I am looking for an Elmer who is familiar with this transmitter and I can work with directly rather than using the AM Window forum directly.  I have a very good copy of the operating manual and schematic and a usable copy of the assembly manual.  I built a Heathkit SB-200 and it worked fine the first time I fired it up so I am not incompetent just lacking the technical expertise.  If there is someone that would like to help me along with this project I would sure appreciate it.

Al, n7ioh

[ke7trp]

You have found 10 or 15 of us.   My advice is to make a post with what area you need help with along the way and post lots of pictures!  Pictures gets people on the thread!

I have two rangers.  I spent alot of time with one of them.  Mine has new caps, Solid state supplys and the audio is opened up a bit. 


Clark

[n7ioh]

I haven't started to do much other than preliminary research and looking over the transmitters.  My first goal is to decide exactly what needs/should to be done and what I want to do and then start to acquire the needed parts.  I don't mind spending a little money now and doing the job right the first time.  I don't want to do the minimum and then keep having problems later fixing this and that.  I want to keep it as simple as practical, nothing radical.  I can do the photos when needed and I would agree they can be a big help with some problems.  I am retired and have the time for the project but money is tight so I will have to go slow.  My reason for seeking an elmer I could work directly with was for saving time and as the old saying goes, too many cooks in the kitchen spoil the the stew.  Sometimes when posting a question on any of the forums you will get so many varied responses that it makes things more confusing for people like me who don't have a good working understanding of electronics.  Much of what is discussed is over my head.  I don't mind seeking forum help on some things but I did not want to tie up the forum with a lot of questions that may seem elementary. 

Al, n7ioh

[ve6pg]

..al...you said alot of this is "over your head"...you have come to the right place....anything you need to know, is available here...this site is full of folks, who can help...believe me, these guys have been a great find for me...anything i want to know is here, regardless of how simple, or complicated the situation is....good luck.....

..sk..

[Pete, WA2CWA]

Personally, I wouldn't make any improvements until I got one working the way it was designed to work originally. Once you've satisfied yourself that the transmitter is operating the way it was designed, then go in and start making "improvements". The 3 wire cord is a notable improvement. A number of other "improvements" floating around the web could be classified as adding sprinkles to an already tasty icing on a cake.

[ke7trp]

Yes.

Step 1.  Clean the rig inside and out.

Step 2. Install 3 prong plug.

Step 3. do something about the lack of a fuse since you used that three wire plug and the johnson had fuses in the plug.

Step 4.  Pull all tubes and check them one by one.

Step 5. Sit down, make a list of all the paper caps in the radio.  Order new ones.  Install them.

Step 6. Get the rig on the air.

Step 7.  Think about modifying and what its going to do to value and your enjoyment.

Step 8. Perform any mods you decide.

Clark

[WQ9E]

Pete and Clark are dead on with making sure it works as intended before you start modding or troubleshooting can be a real bear.

When you replace the Johnson plug with a 3 wire, the fuse should go in the lead where F1 is currently.  The fuse should be in the hot (black or load side) lead which goes to the switch and the neutral lead should connect to the other AC input wire.  You never want to fuse neutral and if you reverse the two AC input leads one terminal of the antenna relay control will be "hot" even with the Ranger turned off.  The fuse should preferably be ahead of the RF filter (L25A,B; C61A,B) so it will blow if one of the line bypass caps shorts.  Theoretically your main breaker would trip if a full short happens but if the caps fails highly leaky it will probably catch on fire before the main breaker trips.  There are better line bypass cap choices today but the ones in the Ranger are somewhat difficult to access so as long as you exercise proper care you should be able to leave them in place.

Be careful to always observe proper safety.  Although the Ranger is a fairly low power transmitter it has sufficient voltage/current capacity to cause electrocution and if a bleeder fails the filter caps will retain a charge even after power off.  So, to work on it: turn it off, unplug it, wait about a minute and then short the B+ and HV caps to ground for safety.  Even if the cap doesn't store a lethal charge if you get hit you are likely to damage yourself or a component when you jerk your hand away.

Finally, R35 (the 20K bleeder/screen voltage adjust) adjustable wirewound resistor is fragile so be careful not to break the fine wire on it.  If you have to adjust the modulator screen voltage after you finish repairs then make sure you loosen the screw quite a bit before you move the tap or otherwise you will break the fine wire.  Mouser has replacements and they aren't horribly expensive but they aren't cheap either.

If you go with SS rectifiers (and I did in both my Ranger 1 and 2), be sure and use proper dropping resistors to get the voltages back where they belong and I would also add an inrush current limiter to reduce the transformer stress since the filter caps will charge quickly through the SS rectifiers.  I put a 3 wire plug on my Ranger 2; the Ranger 1 still has its original plug since it plugs into my Desk KW and it requires a 2 wire plug so that it can be properly oriented for the Desk KW plate relay to operate.  If you stay with a 2 wire plug, always connect a good ground to the Ranger 2 (the ground should be the first connected and the last disconnected).  With a 2 wire plug and with SS rectifiers and inrush limiting, I would suggest putting a 3 or 4 amp standard fuse in the F1 holder in the plug (mark the plug for proper orientation so that this fuse is in the load side) and then put a 20 amp fuse in the other side (which is neutral).  This way the neutral fuse should never blow and this 20 amp fuse is basically there to provide continuity.

Good luck with your repair/restoration.

Rodger WQ9E

[KB2WIG]

Al,
It's not a bad idea to use a camera and take lots  'o pics before any surgery. Don't do what I usda do and do all the mods at one time. Stupid. Ya don't know where you made the mistake, if you do make one.  Resistance checks, voltage checks, one hand in pocket, etc will get you where you want to go...

[n7ioh]

Thanks Pete, Clark, and Roger for the input.  I was planning on doing pretty much what you guys have said.  I will be replacing most of the caps and carbon resistors with the new stuff.  The only mods I am planning on doing in the beginning will be very minor such as upgrading R3 the 18K 2 watt resistor and moving it out of the VFO box.  Upgrading some other resistor and caps and the 3 wire power cord.  I knew about only having one fuse in the new power cord but was not sure on which side it should go (F1 or F2).  Thanks for clearing that up for me.  OK on placing the fuse ahead of the RF filter, that was another question I was wondering about.  Some of the caps I was going to upgrade to are what I believe are called safety caps used on the AC line where when they fail they fail safe.  The inrush current limiter when solid stating I had read about but will wait until I get closer to doing anything major to the transmitter.  My goal now is to get a parts list together for mouser.  I requested their new catalog last week so it should be here soon.  I am keeping two logs one on my computer and one in a note book of everything I am doing for reference. 

Kevin, good point, with my memory the photos could be very helpful.  I could also use them to document my work and if needed for help they would be readily available.

Again thanks guys.

Al, n7ioh

[WQ9E]

Al,

On the resistor I think you are better off increasing the wattage but leaving it inside the VFO box.  The whole assembly seems to stabilize more quickly that way and that was the original design intent.  I have several Johnson rigs with this type VFO (Ranger 1 and 2, pair of Valiants, a Pacemaker and a 500) and on a couple of them I originally installed the new resistor externally but found out through experience that they take much longer to settle down.

You can do the resistor replacement through the side of the box without removing the entire VFO.  It can be accessed from the left (your left looking from the front) by removing that side panel.  If the VFO tuning is stiff or "crunchy" you will need to remove the ball reduction drive and clean the old grease out and then re-lube it.  The drive should be very smooth with no slippage or grabbing when working properly.  To get the reduction drive out you need to remove the front escutcheon.  The whole process takes about 45 minutes (most of the time is cleaning the old grease out).  I use WD-40 as a solvent and dip it in a small dish of the stuff.  Then dry it and repack with any standard bearing grease.  If you do this, take it apart over a dish so you don't lose the ball bearings if they drop out.  They are standard size if one does get away.   

[KD6VXI]

Al,

On the resistor I think you are better off increasing the wattage but leaving it inside the VFO box.  The whole assembly seems to stabilize more quickly that way and that was the original design intent.  I have several Johnson rigs with this type VFO (Ranger 1 and 2, pair of Valiants, a Pacemaker and a 500) and on a couple of them I originally installed the new resistor externally but found out through experience that they take much longer to settle down.

Guess we can call that Johnson's early attempt at a TXVFO

--Shane

[ke7trp]

I used a 5 watt resistor mounted outside on the bottom on my valiants and rangers. Its really tight inside the box. Some are real stable and some drift a bit.  Not a worry.. You talk on a soldi state rig. you OPERATE a boatanchor.

Clark

[WQ9E]

Guess we can call that Johnson's early attempt at a TXVFO

--Shane

Shane,

My Tektronix time mark generator does uses a group of resistors surrounding the can that holds the xtal as a temperature compensator but I think Tek put a little more engineering into temperature stability than Johnson did into the VFO.  The Johnson VFO is fine for AM/CW but using my Valiant with the Johnson SSB adapter or using the Pacemaker/T-bolt combo guarantees the receiving station is going to get to use their receiver vfo or RIT to track me!

Definitely not the rigs to use with people who are worried about perfect stability.  But I would much prefer to work a mentally stable operator with a drifty oscillator than a mentally drifting operator with a stable oscillator.

Rodger

[KD6VXI]

I used a 5 watt resistor mounted outside on the bottom on my valiants and rangers. Its really tight inside the box. Some are real stable and some drift a bit.  Not a worry.. You talk on a soldi state rig. you OPERATE a boatanchor.

Clark

I've actually had people ask me, on the solid state hifi conversions, to have a small amount of TX drift on keyup to match the Johnsons and Barkers.  Simple varactor in the vco, tacked to the heatsink accomplished that, up to 1kc of "bark" on keyup.

Amazing, the backwards steps some take to make new look old again

--Shane

[ke7trp]

Listen to my Globe CHamp.. Keyup up and your at 3863.. With in 2 or 3 seconds your at 3870.. Wooosh.

Clark

[n7ioh]

Just a quick question about tubes for my Ranger II?  I thought I might put some new tubes on my list of items to have on hand just in case I need one.  I just looked at the tube specifications for the 6146, 6146A, and the 6146B tubes.  From what I can see I should be able to use any of these in my Ranger.  My question, which one is preferred if any and why and what about tube brands?   

I have some NOS tubes on hand for my Ranger II already.  Any tubes that are prone to problems in this radio or different tubes I should maybe change to after I get her up and running?  Currently I am planning on upgrading to 6550's after she is up and running and there are no problems.  I am also looking at solid stating the rectifier tubes later on. 

Thanks, Al n7ioh

[ke7trp]

Do a search on 6146s. There are articles explain in detail.

The best I have found are the 6146 RCA tubes.  I did find one brand new Amperex 6146 that put out the most power but other Amperexs have been lower then RCA.  I have about 30 of them if you need any.  Various types and brands.

Clark

[n7ioh]

Thanks Clark for the quick reply.  I have one NOS RCA 6146 but it has not been tested as of yet.  I would like to get a few more while they are still easily available.  I'm not really worried about getting more power as I hope to buy an amplifier when I sell my home and team them up together.  I will have to reduce the power before I run it through the amp anyway.  I am more interested in just having a nice sounding transmitter without too many mods, KISS approach.  I did do a lot of reading about the 6146 tube variations a while back.  I remember there was a tube that could be used in place of the 6146 tubes that would put out more power and if I remember the 6146W was a military version that was suppose to be a heavy duty version.  I actually had a Ranger II a few years ago that I was going to rebuild and get on the air but sold it instead.  I did a lot of reading then about the 6146 tubes and when I was thinking about changing my Drake T-4XC to 6146 tubes.  I am glad I didn't follow through with modding my Drake.  Any thoughts on the other tubes in the Rangers?

Al n7ioh

[ke7trp]

I use my Ranger to test 6146s.  I have a calibrated TV7 tube checker but there is nothing like loading up a tube in the transmitter.

You can put in variable screen voltage to lower the output of the ranger. Its tricky to get the ouput lower.

Mine runs about 65 watts AM with the amperex tube. I got that tube from Tubesandmore.com  They are down the street. I have since purchased a ton of them at ham fests and stuff. I dont sell parts but we do help each other out on AMfone! 

I agree with your aproach.  Just get the transmitter up and running.. Use for a few weeks. Then you can decide if you want to modify it.  I have modified rigs and I have stock rigs with D104s.  Most of the time I have more fun on the old stock or lightly restored rigs.

I have never used anything other then a 6146 in the ranger.. 

Clark