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THE AM BULLETIN BOARD => Technical Forum => Topic started by: kc4umo on August 20, 2017, 07:56:38 PM



Title: Pair of Johnson transmitters.
Post by: kc4umo on August 20, 2017, 07:56:38 PM
Hi everyone. Been a while. Do not get a lot of time to get on forums as of late.

After searching for a long while I finally got a couple of Johnson transmitters.  Not the prettiest ones on the block but at least they are complete.  I did a bit of work for a guy and these were the payment.
A Ranger 1 and a Viking II. Will be a bit of work but will be fun. And with that work should be a good sounding station on the air,

If interested here is a video tour of the two.  But I  will be also doing quite a bit of picture taking and documenting the restore process. I have only worked on a few of these units over the years and have never restored either of the two. So will be searching for a lot of information on these.

https://www.youtube.com/watch?v=HbI19Ki78DA


Title: Re: Pair of Johnson transmitters.
Post by: N1BCG on August 20, 2017, 08:48:40 PM
That's fantastic! Congratulations on getting two classic rigs!

It sounds like you're already familiar with these so the restoration should go smoothly, and the best part is that nobody will notice the chipped paint. All anyone remembers is that you were running a restored Ranger or V2.


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on August 20, 2017, 09:33:21 PM
That's fantastic! Congratulations on getting two classic rigs!

It sounds like you're already familiar with these so the restoration should go smoothly, and the best part is that nobody will notice the chipped paint. All anyone remembers is that you were running a restored Ranger or V2.

Thanks. I have looked for a long time for a couple of these rigs.  Most were beyond repair of fully restored. I think I got lucky to find two that are complete with most of the original caps.  I am no expert on these at all. I have watched a few videos and read a lot of articles on them. Even worked on a few over the years. But this will be my first restore on these models. I think it will be fun.


Title: Re: Pair of Johnson transmitters.
Post by: WA2SQQ on August 21, 2017, 09:05:05 AM
Buddy
Your YouTube channel is one of my favorites. I was wondering if you were a ham. Glad to have you here and keep up the good work! Hope to hear you on AM, soon!

Bob


Title: Re: Pair of Johnson transmitters.
Post by: wb6kwt on August 21, 2017, 09:06:54 AM
Hi Buddy,

Looking forward to your videos on these two transmitters, I'm working on a Valiant and have a Viking II waiting for some TLC too. I really enjoy watching your video and have learned a lot of things from you.

Bob - wb6kwt


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on August 21, 2017, 06:46:33 PM
Buddy
Your YouTube channel is one of my favorites. I was wondering if you were a ham. Glad to have you here and keep up the good work! Hope to hear you on AM, soon!

Bob

Thank you Bob. I am pleased to hear you like the videos. I try and keep things at a non techno speak plain language style and it seems to work.  I used to read and post here quite a bit before things got busy. Keeping up with fan mail is a job! Over two thousand mails in the last 7 days.  I will be around a bit more.








Hi Buddy,

Looking forward to your videos on these two transmitters, I'm working on a Valiant and have a Viking II waiting for some TLC too. I really enjoy watching your video and have learned a lot of things from you.

Bob - wb6kwt

Another thanks to you too Bob. These are fun to work on. I already tore into the Ranger and finding some interesting presents left behind by others.  Tells a great story of it's life. I will be documenting and video the whole process. Much more to come.

Thanks to the both for the support.


Last night and this afternoon I went ahead and removed the front panel of the Ranger. Then got the VFO cover off to see how things looked.  I found the phenolic behind the vernier was gone. Nothing but dust on the floor.
Also the grease was hard as a rock. The VFO platform looked great and found the OA2 regulator tube had a melt down. Someone has changed the dropping resistor already to a 7 watt wire round.  So time to rebuild the VFO because this is a bit of work to get back into.



Title: Re: Pair of Johnson transmitters.
Post by: wb6kwt on August 21, 2017, 07:49:16 PM
Buddy, there is a guy on ebay selling a nice replacement for the coupler phenolic piece, $10 plus shipping  it's, well made. I know you will probably make your own but I wasn't sure I could make it without making a mess of it.

Bob -wb6kwt


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on August 21, 2017, 08:42:13 PM
Buddy, there is a guy on ebay selling a nice replacement for the coupler phenolic piece, $10 plus shipping  it's, well made. I know you will probably make your own but I wasn't sure I could make it without making a mess of it.

Bob -wb6kwt

Great I will take a look at it. But like you sais I will most likely make one. Very simple and hard to mess up. You can make it square or round.  Depending on the thickness of the material. Round thick ones do not flex that good.  Thanks for that information.


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on August 25, 2017, 09:28:39 AM
Well had a little time this week to clean up the chassis a bit. Also made a parts list so I can get the necessary parts on order. Will probably go ahead and order the capacitors for the Viking II so will have them on hand.

If things go well I will get a bit done over the week end.  Projects like this can take a lot of time.
Need to find a potentiometer for the drive control. This one is shorted.


Title: Re: Pair of Johnson transmitters.
Post by: WA2SQQ on August 28, 2017, 08:52:30 AM
I picked up a can of that rubbing / buffing polish you mentioned. Using it on two Heath RX's that I'm working on. That stuff really does an incredible job on the aluminum chassis. Thanks for the tip. Just curious, you ever have any experience with a Sencore LC101 "Z" Meter? Got a strange problem with the ESR function and no schematic.


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on August 28, 2017, 03:41:24 PM
I picked up a can of that rubbing / buffing polish you mentioned. Using it on two Heath RX's that I'm working on. That stuff really does an incredible job on the aluminum chassis. Thanks for the tip. Just curious, you ever have any experience with a Sencore LC101 "Z" Meter? Got a strange problem with the ESR function and no schematic.

It is great stuff.  I use that, Brasso and gojo hand cleaner for all my restorations.

On the Sencore have you checked the relay? They go bad at times.  As you already notice no schematic can be found in PDF format. They do however turn up on ebay.
I have the manual but there is no schematic in it.


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on August 28, 2017, 03:44:14 PM
Well after a week end of work the Ranger came to life today.  Replaced all caps, 25K 4 watt drive pot, 6cl6 and OA2 tube, along with a hand full of resistors.
Audio sounds pretty good. Rig does not work in CW mode so need to troubleshoot that.


Title: Re: Pair of Johnson transmitters.
Post by: WA2SQQ on August 29, 2017, 08:18:44 AM
On the Sencore have you checked the relay? They go bad at times.  As you already notice no schematic can be found in PDF format. They do however turn up on ebay.
I have the manual but there is no schematic in it.

So last night I decided to remove the PCB's and start by cleaning and reseating all the connectors. To my surprise, that did it - credit goes to Deoxit! Found the info on their "special" cable which is made of RG-62. Got hold of an old LAN jumper cable that already had BNC's installed. All done - on to the next project - a "moused" SB-310


Title: Re: Pair of Johnson transmitters.
Post by: KB2WIG on August 29, 2017, 10:17:57 AM


If i rember, there is a procedure for adding a few resisrors in series with the drive pot thereby lowering the dissipation. Im not at home so my notes are not at hand.

Klc





Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on August 29, 2017, 09:54:28 PM


So last night I decided to remove the PCB's and start by cleaning and reseating all the connectors. To my surprise, that did it - credit goes to Deoxit! Found the info on their "special" cable which is made of RG-62. Got hold of an old LAN jumper cable that already had BNC's installed. All done - on to the next project - a "moused" SB-310

Deoxit  is some good stuff. Glad you got it goind


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on August 29, 2017, 09:56:11 PM


If i rember, there is a procedure for adding a few resisrors in series with the drive pot thereby lowering the dissipation. Im not at home so my notes are not at hand.

Klc




You may be on to something there. Yesterday I ran into an article where this was mentioned. But no further details were noted. I would be interested in what your note have to offer.


Title: Re: Pair of Johnson transmitters.
Post by: KB2WIG on August 30, 2017, 12:13:33 AM


Look at this,

                                            http://www.ad5x.com/images/Articles/Ranger%20Mods.pdf    ,

particularly " Protecting Drive pot R13 ".

You should (well, in my opinion ) look at     

                                            http://www.amwindow.org/tech/htm/mods.htm             

and review the material available. Don't just look at the Johnson stuff, look at the whole resource.

good luck.


klc


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on August 30, 2017, 04:12:27 PM
I will verify this over the week end but I have a feeling these resistors are the drive pot modification. Or at least a crude attempt.
Some good stuff on those links you shared. I will spend days looking that over. Thanks


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on September 03, 2017, 07:54:52 PM
Got part one of the Ranger restoration edited and uploaded.


https://www.youtube.com/watch?v=ImVTRCr2KRs


Title: Re: Pair of Johnson transmitters.
Post by: WA2SQQ on September 03, 2017, 09:27:19 PM
Just watched it - you make it look easy! Can't wait to work you on the air when you fire it up.


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on September 04, 2017, 10:13:39 AM
Just watched it - you make it look easy! Can't wait to work you on the air when you fire it up.

Cool. Actually it was very easy. The design and layout of these old rigs helps.  Cannot wait to get it on the air. Just have to freshen up one of my old receivers soon. All I have is a couple of Nationals, NC-98 and a NC-155. Got to find something better.
Thanks


Title: Re: Pair of Johnson transmitters.
Post by: wb6kwt on September 05, 2017, 07:23:26 AM
Buddy, thanks for the video, looking forward for part 2. What is the "foam" you sprayed on the tooth brush?


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on September 05, 2017, 11:50:23 AM
Buddy, thanks for the video, looking forward for part 2. What is the "foam" you sprayed on the tooth brush?

Thanks.
The foam is nothing more than a product called "Totally Awesome". Drilled small holes in the pickup tube so when you squeeze the trigger it comes out as a foam. It is really a good cleaner and cheap too. Hope that helps.


Title: Re: Pair of Johnson transmitters.
Post by: wb6kwt on September 05, 2017, 07:50:48 PM
Thanks, never heard of it.

Bob


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on September 05, 2017, 09:58:07 PM
You can find it at Walmart, truevalue ect. Cheap but works great and not as harsh as other cleaners.


Title: Re: Pair of Johnson transmitters.
Post by: KE5YTV on September 06, 2017, 12:44:31 PM
Thanks for taking the time to make and post the videos. I've got a few Johnson's on the restoration shelf including a Ranger 1 & 2. It's always good to get a few hints and kinks.


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on September 06, 2017, 09:34:34 PM
Thank you Mike. It is my pleasure to do the videos.  I am far from being an expert, just an average person. I really do like learning things and sharing what I have.

Hope to see some progress on your restores.


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on October 21, 2017, 08:54:45 PM
Picked up a Johnson 122 VFO for the VII. It is a little rough on the outside but looks great on the inside.
Started the tear down of the unit today. Will get some video of it shortly.


Title: Re: Pair of Johnson transmitters.
Post by: K9PNP on October 24, 2017, 01:23:01 PM
Picked up a Johnson 122 VFO for the VII. It is a little rough on the outside but looks great on the inside.
Started the tear down of the unit today. Will get some video of it shortly.

Your 122 looks better than mine and so does your V2.  As I have been told before:  Nobody cares a whole lot what your rig looks like [except you] as long as it sounds good.  I did do a minor rebuild on the audio chain on the V2 a few years ago which improved the audio quality somewhat.  Found a 5 watt variable resistor to replace the drive control, believe it was from Mouser.  Only issue was size, but it's doable.  Not really good at physical restoration any more; get up and go is just not there as much any more.


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on October 24, 2017, 07:40:58 PM
Picked up a Johnson 122 VFO for the VII. It is a little rough on the outside but looks great on the inside.
Started the tear down of the unit today. Will get some video of it shortly.

Your 122 looks better than mine and so does your V2.  As I have been told before:  Nobody cares a whole lot what your rig looks like [except you] as long as it sounds good.  I did do a minor rebuild on the audio chain on the V2 a few years ago which improved the audio quality somewhat.  Found a 5 watt variable resistor to replace the drive control, believe it was from Mouser.  Only issue was size, but it's doable.  Not really good at physical restoration any more; get up and go is just not there as much any more.


I agree it is not really that bad looking. I am just going to clean everything and not worry about the battle scars. All I did to the Ranger 1 and it works pretty good.

The V2 does work. Very surprising to me. There were a few wires that had been disconnected, one was to the oil filled cap (C9). I powered it up and got 100 watts out on cw. Still learning how to use these rigs. There is no audio out or cw tone. Going to go ahead and re-cap the rig, check resistors and do some touch up on the wiring and controls.  I pulled all the tubes today and getting ready to remove the front of the unit. Lots of dust has settled in. I call that protective dust. Preserves the beauty beneath it.  I did find the 122 does work. But I am questioning those mica caps. Saw some noise on the SA that should not be there.

Will get a video on the restore of both units.
Now to find a good receiver to go along with these.


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on October 25, 2017, 04:13:16 PM
went through the VFO and for the most part it is working.  The V2 does work as is but very dirty and needs upgrading. Puts out full power but did not want ot keep playing around with it due to the dust and grime in the rig.  With the front panel and covers removed from the chassis I can get a good look at everything now.  The roll inductor looks great just dirty.  No burnt spots. The small roller squeals like a pig when it moves across the shaft. So when all that is cleaned up need to find a good lube for it.


Title: Re: Pair of Johnson transmitters.
Post by: w1vtp on October 25, 2017, 10:10:05 PM
Picked up a Johnson 122 VFO for the VII. It is a little rough on the outside but looks great on the inside.
Started the tear down of the unit today. Will get some video of it shortly.

Would have been nice if the downloaded pictures weren't thumbnails.

Good luck with the project


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on October 26, 2017, 05:50:15 AM
Picked up a Johnson 122 VFO for the VII. It is a little rough on the outside but looks great on the inside.
Started the tear down of the unit today. Will get some video of it shortly.

Would have been nice if the downloaded pictures weren't thumbnails.

Good luck with the project

I will link in the larger pictures.


Title: Re: Pair of Johnson transmitters.
Post by: w1vtp on October 26, 2017, 09:36:33 AM
Thanks for the larger pics.  You're a lot braver than I am.  I have a pair of Vikings with VFOs. They are in excellent cosmetic shape. The V1 is working. I'm embarrassed to say I don't know the status of the V2 even though I've had it on the work bench for over a year.

The 122's have a reputation for being drift-o-matics if they have been left in as-received conditions. Your TLC is to be appreciated.   When I was a kid, I wanted the V1 so bad but never had the cash for it. Decades later I did get my V1 & V2s. You are shaming me to get off my butt and get started on my V2.

This is making for excellent reading.  Keep those pics and progress reports coming.  I think the EFJ Viking series is the ultimate in an excellent rig for us "kids" who what an affordable but effective 100 watt class rig

Al,  VTP


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on October 28, 2017, 09:33:55 PM
Thanks Al, yes those larger pics work better here. Don't feel bad, I have stuff on the bench for quite a while myself.
The Johnsons is something I have been wanting for many years. This gives me the fuel to work on them.

I have tore the V2 apart. Removed the tank assembly and shields. Working on cleaning up the chassis and polishing it. A lot of work but will be rewarding. I have taken lots of pictures of the progress while recording the video. Now this is when I wish I had a larger ultrasonic cleaner to sit the tank unit in. Need it to be as clean as possible as any contaminates on the roller inductor could leave to disaster. Or a bunt spot on the winding. Good thing the whole tank unit can be removed without any desoldering.

Lots to come soon.


Title: Re: Pair of Johnson transmitters.
Post by: WO4K on October 29, 2017, 08:11:15 AM
Picked up a Johnson 122 VFO for the VII. It is a little rough on the outside but looks great on the inside.
Started the tear down of the unit today. Will get some video of it shortly.

Radio Daze is offering faceplate refinishing for the 122. See:
http://www.radiodaze.com/viking-model-122-vfo-faceplate-item-fp-efj-vk122/

They are also refinishing the faceplate for my Viking II CDC. Below is a .pdf of the the artist's final proof copy sent for my approval. I will be delighted if the faceplate comes back looking that good.


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on October 29, 2017, 08:59:56 AM
Picked up a Johnson 122 VFO for the VII. It is a little rough on the outside but looks great on the inside.
Started the tear down of the unit today. Will get some video of it shortly.

Radio Daze is offering faceplate refinishing for the 122. See:
http://www.radiodaze.com/viking-model-122-vfo-faceplate-item-fp-efj-vk122/

They are also refinishing the faceplate for my Viking II CDC. Below is a .pdf of the the artist's final proof copy sent for my approval. I will be delighted if the faceplate comes back looking that good.


Yes been looking at those. Let us know how yours turn out.  The picture looks awesome. I am still on the middle of the fence about the comedic condition of my rigs.
One part of me likes the idea of having "like new" transmitters while the other part likes the "used" look.  May just get the decals and stuff and save them for later use....Decisions.......

Thanks for sharing.


Title: Re: Pair of Johnson transmitters.
Post by: KB2WIG on October 29, 2017, 09:28:27 AM

The CD warning has the word  "IF " in plase of "OF"....   maybe they shuda used PROOF as a watermark.

How do you intend cleaning the tank, particuraly the roller inductor? I've worried of contaminating the ceramic.

KLC


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on October 29, 2017, 12:36:42 PM

The CD warning has the word  "IF " in plase of "OF"....   maybe they shuda used PROOF as a watermark.

How do you intend cleaning the tank, particuraly the roller inductor? I've worried of contaminating the ceramic.

KLC

Very good question. As some ultrasonic cleaners could damaged the ceramic. I will start out by soaking it in  distilled water that is luke warm then followed by a warm vinegar/salt bath then followed by a distilled water rinse.  The main thing is to keep contaminates out of the ceramic. As these contaminates could lead to arcing.  Would love to hear how others would approach it myself as this is the type of material you do not find on the net.

I am sure there are others that have better ways of doing this and some that have never giving it a thought.


Title: Re: Pair of Johnson transmitters.
Post by: WD4DMZ on October 29, 2017, 02:16:15 PM
Very enjoyable thread. Keep posting.

About 18 months ago I acquired a V2 in parts that an area ham had given up on. Pretty clean but sold as is and not working.

After replacing the caps and a few resistors I adjusted it per the manual and buttoned it up to give it a try with the intent of going back into it and cleaning it up better and adding a few missing parts. The initial on air reports were so good I decided to leave it alone and have been using it about 90% finished ever since.

One set of parts still in a box is the coil/switch that enable use on 160 meters. I do not use 160 much and getting the parts installed will require a lot of effort. Also, the tuning dial needs adjusting as it reads way off what it should at resonance but that is a simple mechanical adjustment.

One issue that still remains is that the xtals do not resonate at their nameplate frequency. There are no trimmers so I added a few mmf in parallel with each one to get them within 100 Hz of where they should be. The caps in the circuit must be bad but that will wait as I am well within everyone's receiver passbands. Only the SDR users notice.

I also picked up a 122 VFO that was sold as working and I believed the seller so did not check it out previous to plugging it in. The prior, prior owner must have modded it for some other xmitter as a wire was out of place and it caused the choke under the main coil to blow up - literally. Whew! The choke acted as a fuse and saved the V2 from serious damage. Fortunately the gent I had purchased the V2 from had accumulated some extra parts and there was an extra choke in the box of parts.


When going thru the 122 be sure to look for a non obvious mod or wire out of place so you do not experience what I did. One observation on the VFO... after about 30 minutes of warm-up the 122 is really stable and stays right on the mark.

Good luck,  Rich


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on November 03, 2017, 04:45:05 PM
Thanks Rich. Sounds like you got that rig singing along now. I love hearing stories like this also.

Well I spent the better part of the week doing nothing but cleaning. I was thinking of polishing the chassis out but decided not to. A lot of work for something you cannot see most of the time.  I am going to do some electroplating though. Either nickle or copper. Cannot make my mind up yet. Since there is a pit of copper in the rig may be the way I go. Some of the brackets that hold controls and the large one around the tank is pitted and flaking off.  So may plate them soon.

Anyway here is a couple of pics.


Title: Re: Pair of Johnson transmitters.
Post by: KB2WIG on November 03, 2017, 04:56:05 PM


Nice work. It looks much better than my VK2.  Now I'm jealous.

klc





Title: Re: Pair of Johnson transmitters.
Post by: WD4DMZ on November 03, 2017, 11:28:52 PM
Wow... that is nice!

Rich


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on November 04, 2017, 11:59:52 AM


Nice work. It looks much better than my VK2.  Now I'm jealous.

klc





Thanks. Now do not be jealous, although the inside looks pretty good the outside is a different story.



Wow... that is nice!

Rich

Appreciate the comment. Thanks.

I have the chassis back together. All cleaned. Waiting on the post to drop off my capacitors and resistors now.  Done so many cap jobs lately I had ran out of stock. Possible they will arrive today. If not Monday then.

Now I can start checking the tubes and component checks. I have a lot of video footage on the V2 and 122 vfo I will upload soon if time allows.

 



Title: Re: Pair of Johnson transmitters.
Post by: MikeKE0ZUinkcmo on November 08, 2017, 10:21:11 AM
Buddy, I have to agree those rigs look pretty darn nice inside, and it's a lot of work getting them clean using the typical processes.   There's nothing better than working on a clean radio, but I've found a much quicker way to get those classics ready for the repair bench.  

I've used the pressure washer on the trucks, tractor, and mowers for several years and the thought of using it on radios, at first seemed pretty far fetched.   Then I tried it on an old parts donor and was really impressed with the result.   I have since used it on several radios and it makes short work of the whole cleaning process.  

There are a few precautions, like making sure there are no dials that can't get water on them, removing all the meters, keeping water out of the bottom side of the power transformers, and don't fill up the I.F. cans.  Some transmitter tank coils need a little caution as well.   Final step is to do a thorough rinse with distilled water and set the unit out in the hot sun for a couple days.  Here are a some examples, and yes, all are alive and well.


My Viking II (https://mikeharrison.smugmug.com/EF-JOHNSON/VIKING-l/Viking/i-GbcnGnC/A)

This is the  2-40D I finished aligning yesterday, and used on the MOKAM morning net. (https://mikeharrison.smugmug.com/NATIONAL/NC240D/THE-BATH/After-the-bath/i-WDJNnxh/A)

My National 183D (https://mikeharrison.smugmug.com/NATIONAL/NC183/183/i-ncctLpL/A)

...And an AR88.  You can see how the fabric wire colors came back and the whole thing looks almost new.   This took about 20 minutes.
(https://photos.smugmug.com/RCA/AR88/i-WN8Gr9P/0/638fc5d6/L/P8310001-L.jpg) (https://mikeharrison.smugmug.com/RCA/AR88/i-FSJzx5W/A)


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on November 10, 2017, 01:26:44 PM
Buddy, I have to agree those rigs look pretty darn nice inside, and it's a lot of work getting them clean using the typical processes.   There's nothing better than working on a clean radio, but I've found a much quicker way to get those classics ready for the repair bench.  

I've used the pressure washer on the trucks, tractor, and mowers for several years and the thought of using it on radios, at first seemed pretty far fetched.   Then I tried it on an old parts donor and was really impressed with the result.   I have since used it on several radios and it makes short work of the whole cleaning process.  

There are a few precautions, like making sure there are no dials that can't get water on them, removing all the meters, keeping water out of the bottom side of the power transformers, and don't fill up the I.F. cans.  Some transmitter tank coils need a little caution as well.   Final step is to do a thorough rinse with distilled water and set the unit out in the hot sun for a couple days.  Here are a some examples, and yes, all are alive and well.



...And an AR88.  You can see how the fabric wire colors came back and the whole thing looks almost new.   This took about 20 minutes.


Nice looking rigs!
Great job on cleaning those up and getting them going.  Thank you for sharing your work.
Most of the time I have no problem spaying an old rig down and hosing it off. Done this many times. And they always turn out nice. Since I have been remodeling the kitchen in the house I bought new appliances,  I have already moved the oven over into the garage here in the shop. I have two plans for it. One is I am going to build a box that is thermal insulated. Open the door and the box will sit on the door. This will increase the size and will be used as a oven for powder coated parts. The other plan is to use it to dry rigs after as good washing. 150 to 170 degrees should be fine.

Got so it takes me longer to do repairs now since i  video record everything.

Again, thanks for sharing and reading.

I really like the looks of the V2 on the inside.  I got all my needed capacitors this week, now just need time to get to replacing them.  Time has been limited due to the public job and house remodeling.


Title: Re: Pair of Johnson transmitters.
Post by: KB2WIG on November 10, 2017, 01:52:47 PM


M,

How do you keep the water out of the pwr transformers? Do you cover them?, block them? Stuff the holes?

The only power washer I could use is at the diy car wash. Is this your method also?

I have washed boatanchors off with a garden hose, just 'flooding' the tops of a chassis.  In the past, I've put small things in the trunk to dry them off.  Now, with the weather the way it is, unless the wife was away, I'd end up using a fan to dry things out. Maybe a lamp inside a cardboard box...

klc



Title: Re: Pair of Johnson transmitters.
Post by: MikeKE0ZUinkcmo on November 11, 2017, 12:01:08 AM
Hi Kevin,

I use masking tape and just cover the holes where the leads come out of the transformer if it's the enclosed type, and be careful not to flood  that area.   Open frame types I wrap masking tape around the whole transformer.  For IF cans, just a little patch over the holes.   

I've used the DIY car wash before, but I have a smallish pressure washer that I also use for cleaning the cars, tractor and riding mowers.

The important points in my book are, one, final rinse with liberal amounts of distilled water, and use either compressed air or a leaf blower to get most of the water off quickly, then, allow a couple /  three days in the hot sun, or in a ventilated oven at 170 degrees or so for at least 24 hours.

I clean most of mine in batches, and they wind up setting in the Queue for a few weeks at least, so they are plenty dry by the time I get them on the bench.


Title: Re: Pair of Johnson transmitters.
Post by: KB2WIG on November 11, 2017, 01:27:01 PM

M,

Thanks fer the dope information.

I'll probably spray the babies with 50% ammonia and water mix, followed by the sparkle city pressure wash. I usta have an 'endless' supply of deionized water, but that's gone.  Looks like a few 1gal jugs from the local  dollar store or Wegmans. The basement is running ~45% humidity, so it looks like it will be a leaf blower before a space heater into a cardboard box.  That leaf blower idea is a gud one. (I've an electric oven, but you know why it not going to be used.)


klc


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on November 12, 2017, 07:45:24 AM
Been tied up and did not get a lot done this week en so far.  Had to finish up a review / repair video from a product I received a few weeks ago. I did get my capacitors in from Just Radio so yesterday evening stated the replacement.
First was to tackle the high voltage filter caps.  Two 15Mf @450 volts and 2 @150 volts. I changed the 15 @ 150 to 16Mf  @ 160 volts.

I installed 2 terminal strips where the original caps were located, one 5 terminal and one 3 terminal. In the negative supply the 150 volt caps positive end tie to ground.

The small caps fit in perfect and take up less room than the originals.
Today will get the other two electrolytic replaced along with all the wax caps.


Title: Re: Pair of Johnson transmitters.
Post by: MikeKE0ZUinkcmo on November 12, 2017, 08:02:22 AM
Nice work!   It's amazing just how much smaller electrolytics are today, compared to 50-60 years ago.

Mike


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on November 13, 2017, 03:33:52 PM
Nice work!   It's amazing just how much smaller electrolytics are today, compared to 50-60 years ago.

Mike

Thanks Mike. Yes these new capacitors are so much better today.  Gives a lot if room to free up also.
Got all the caps replaced. I did find both 10 Mf caps in the speech and audio circuit leaky.
Now to check resistors and other components. Then start testing tubes.


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on November 15, 2017, 08:37:25 PM
Success  !

So here is where we are at on the VII.

All electrolytic and wax caps changed.  Spent Monday and yesterday evening cleaning the tubes, knobs and reinstalling all them.  Nothing belter than working on a clean boat anchor with fresh capacitors installed.

When I first got this rig I know there was two problems the original owner told me about.

Intermitted transmit When transmit dropped out there was plate voltage, no grid, buffer or oscillator.
Second problem was no audio or cw tone when it would transmit.

So tonight I brought the VII up on a variac and all was fine. Went by the book and tuned the rig on 40 meters with no problem. Nice dip of the plate and saw 120 watts on the external meter.  I pressed the cw key and heard a tone in a near by receiver.  The tone would change though from a high pitch to a low pitch tone.

Connected a mic, switched to AM and set it up. Flipped the plate switch, spoke in the mic while turning the audio up.  It sounded great on the 747 receiver sitting on the shelf.  Not bad at all.

So I wanted to start checking voltages, high and low supplies, bias ect.  Now the whole time I am recording this for the video. I fired the rig up. flipped the plate switch and saw the meter rise. Hit the key and nothing. I looked over at the spectrum analyzer and saw no spike in the 7 MHz range.  Flipped the meter to oscillator and nothing.  Pulled the crystal and did an external check and it was fine.  Now during this time I have not checked or replaced any tubes, Wanted to do a trouble shooting walk through video.

Pulled the 6AU6 osc tune and changed it out with a known good tune. Still nothing.  Put original tube in and started getting late on me.  I was probing around under the tube (V6) and then saw the spike rise on the SA. Then it sank as quick and it came.

So no oscillator running. I think I need to check the wiring under the tube, cw / phone switch, and crystal board. I have not yet check the LV supply. What ever is causing the problem seems to be  intermitted.  Really should be something simple.

More to come.


Title: Re: Pair of Johnson transmitters.
Post by: K1JJ on November 16, 2017, 12:37:23 AM
You're a good troubleshooter and restorer, Buddy!  In this day and age of throw-aways and board changers, a person who can troubleshoot down to the component level is getting rare. They are grossly under-appreciated considering the thousands of hours it takes to get really good at it.

It's a science and an art. You have the right attitude; always keeping calm and plugging away. With that combination there's nothing you can't eventually get working right.

Your video documentation will help a lot of hams in the future.

T


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on November 17, 2017, 09:11:44 PM
You're a good troubleshooter and restorer, Buddy!  In this day and age of throw-aways and board changers, a person who can troubleshoot down to the component level is getting rare. They are grossly under-appreciated considering the thousands of hours it takes to get really good at it.

It's a science and an art. You have the right attitude; always keeping calm and plugging away. With that combination there's nothing you can't eventually get working right.

Your video documentation will help a lot of hams in the future.

T

Thank you for those very kind words and vote of confidence. 
Repairing electronics is very relaxing to me. I enjoy a good challenge.  I find it like a good murder mystery or detective story.  I hear so many folks say that repairing old radios is a dying art,  I find it as being a lost art.
Since I started the video blog I have had many folks mail me saying how much it has inspired them to get into repair. Speaking of email I get several hundred a week now. Hard to keep up with them.

Thanks why I do this, is to help give others that push they need to get started. Just the comments I see is very rewarding. Thanks again.

Anyway I am off tomorrow and plan to look over the oscillator issue.  The oscillator seems very strong as I can hear it in the near by receiver.  I believe there is a resistor that may be causing the problem I did try the 122 and did not get any signal out.  Have to dig into that deeper. Going to try and upload some video on the VII this week  end.


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on November 18, 2017, 11:00:09 AM
This morning I have been playing around in the oscillator circuit.  At the moment it will not fail.
Hard to troubleshoot a problem that does not want to rear it's ugly head.
So I grabbed the 122 and connected it to the rig. Nothing! After spending a bit of time looking things over I grabbed a key and plugged it into the rear of the vfo, engaged the shorting bar and bam! Good strong signal. Frequency is way off. Got to do a bit more reading on this thing. But it is working and was able to drive the transmitter with no problem.  BTW the V2 front panel cleaned up pretty good.

More to come.....


Title: Re: Pair of Johnson transmitters.
Post by: KB2WIG on November 18, 2017, 08:09:37 PM


Love your multimeter cradles...   Guess I've another project to start.

klc


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on November 18, 2017, 09:41:41 PM


Love your multimeter cradles...   Guess I've another project to start.

klc


Thanks.
I never cared much for the installed kick stand they came with.  They fall over and the angle just was not right. When recording video there was always a glare.  Just grabbed some scrap wood and that is what I came up with.

Here is a better picture


Title: Re: Pair of Johnson transmitters.
Post by: WD4DMZ on November 20, 2017, 04:11:44 PM
Frequency is way off

The 122 is really easy to calibrate. I had mine on the money for all the ranges in minutes. Just wait about 30 minutes for it to warm up first as mine drifts a lot while warming. However, once warm it stays dead on according to reports I have received.

Another issue is the way the dial is calibrated. The marker freqs are to the right of the main hash marks. Initially I was trying to center above the center of the indication. For instance, the 7.25 Mhz is under 7.26 and 7.27 but 7.25 is the long line to the left of the #. Initially I found that odd.

Rich


Title: Re: Pair of Johnson transmitters.
Post by: kc4umo on November 23, 2017, 07:37:35 AM
Frequency is way off

The 122 is really easy to calibrate. I had mine on the money for all the ranges in minutes. Just wait about 30 minutes for it to warm up first as mine drifts a lot while warming. However, once warm it stays dead on according to reports I have received.

Another issue is the way the dial is calibrated. The marker freqs are to the right of the main hash marks. Initially I was trying to center above the center of the indication. For instance, the 7.25 Mhz is under 7.26 and 7.27 but 7.25 is the long line to the left of the #. Initially I found that odd.

Rich

Thanks Rich,
Yes it is a bit odd the way this reads the frequency.
Problem I see with mine is like I said it is way off.  I set the dial around 7.1 MHz and it transmits at 7.8MHz.  Before I go and start turning trimmers I need to check and make sure everything is within specification.  Could be someone changed something to cover different parts of the band, not sure yet. I will get further into it this week end.
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