Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

donate to eham
   Home   Help Search  
Pages: [1] 2 Next   Go Down
  Print  
Author Topic: VIKING RANGER HELP NEEDED VERY EARLY VERSION  (Read 958 times)
KC0VVB
Member

Posts: 58




Ignore
« on: August 27, 2019, 04:06:04 PM »

very early kit built viking ranger. No keyer platform with bias, no ptt mod. Working on for 3 months. Was complete original when first opened. previous owner appears to have replaced some resistors and added 5k ohm on the end of r35.

Recapped electrolytics by my self and resistors the 1 watt carbon and metal film flame proof.

fired it up for the first time 2 months ago one fine saturday hit all the specified meter readings in the manual during operation.
200w out on phone peak reading watt meter in to dummy load. Talked for 6 hours. That was the last time it ran right.
I installed a 3 prong plug wired the hot and neutral correctly. When i pluged it in i discovered the new edition the ham shack was in had the outlet wired backwards and the ground prong in the outlet was not connected, so when i plugged it in things went pop. The 3 prong plug didn't have a fuse of course i have since installed one.

What have I done so far after turning on rig all parts were working as before except no output from final
Logged
KC0VVB
Member

Posts: 58




Ignore
« Reply #1 on: August 27, 2019, 04:07:14 PM »

After operating for a few days to determine issues now no modulation either.
What did i find so far voltage checks revealed loose heater connections at the oscillator of the vfo. The heater of the 6146 final had a heater lead that acted like a fuseable link and seperated right allong the edge of the insulation where it connected to the socket. The tail was blown off a resistor that connected the 12ax7 to the low b+ and disconnected all the low b+.

The screens of the 6146 should be 190 but i measure 280 phone and 20 cw.
1614 modulator screens should be 300 but measure 153. grid bias should be -28 but measures -13.
The plate of the 6aq5 clamper tube specifies 185 but is only 100v.

The resistance checks at the T3 audio driver transformer primary  should read 270 i read 1260 ohms i have since replaced it with the correct ranger replacement.

I removed the extra resistor from R35 and set the modulator resting current to 70ma.

The 25k ohm 4 watt ohm drive pot was open and i replaced that.

I replaced 5 or 6 the creepy silver mica postage stamp caps not in the vfo with mica silver dipped. 20 50 300 500 puff.

I checked and replaced many of the original green ceramic caps with new blue 3Kv. Even though some checked ok i spotted some hair line cracks and also the ones on the ac line with the big holes in them.

There was a ground lug near one of the modulator tubes with capacitors attaches that was never soldered.

Blew the halo off the new 6aq5 which has been replaced with the 5aq5 that was in there when i got it previous.

all tubes are new except the 6aq5 6ax4 and 5r4gy which are on order.

Still no output and no modulation. I see plate meter swing on cw in vfo and crystal.
Logged
KC0VVB
Member

Posts: 58




Ignore
« Reply #2 on: August 27, 2019, 04:15:16 PM »

Is there something i am missing could it be a bad crystal vfo switch or operate switch i dont see any burned contacts.
 
I suspected the original 6aq5 is soft and replaced it and the 5ax4 low voltage rectifier
Tonight with new ones. No change in the no final output or modulation situation.

Any advice would be appreciated i am running out of ideas.
Logged
KC0VVB
Member

Posts: 58




Ignore
« Reply #3 on: August 27, 2019, 06:15:36 PM »

after installing the new 6aq5 i re measured the voltages that were previously off.
manual specified measurement/ actual measurement.
6146 final screen cw key down and phone 190v/214v and 190v/214v.
6aq5 clamper plate 185v/214v. 6aq5 clamper screen is 255/183.
6aq5 clamper negative bias at the control grid is -65v.
6l6gc modulator tubes screen 300/183 6l6gc grid bias -23v/+13v
any suggestions would be helpful.

Why is the clamper and modulator screens so low and the modulator bias so high at positive 13 volts? 

 
Logged
KM1H
Member

Posts: 5559




Ignore
« Reply #4 on: August 27, 2019, 06:41:43 PM »

Replace ALL electrolytic caps, which includes the C77 700V cap in the HV with a pair of 20-30uf 450V in series with 100K 1W equalizer resistors across each, plus any paper caps (even if enclosed in plastic) for starters and then test again.

Dont be surprised if a number of those small carbon resistors are way out of tolerance now. Johnson used several vendors so anything is possible.

Reseat all tubes several times to break thru storage corrosion.

The 6AL5 bias rectifier has a history of failing. Dont go to SS in place of any rectifier.

Use another radio to see if the VFO is working.

Once it is somewhat running again replace the VFO tube with a 6AH6 for better stability.

Use another radio to see if the VFO is working.

Carl
Logged
K0ZN
Member

Posts: 1862




Ignore
« Reply #5 on: August 27, 2019, 08:01:24 PM »

Something doesn’t make sense.  You said you were getting 200 watts out ?!  Maybe that is a typo. That seems impossible if the rig really is a Johnson Ranger with one 6146 tube in the final. That would burn up the tube very quickly. I had a Ranger for many years... great rig in is day, but there is no way it could put out that kind of power. I highly doubt the power supply could support that kind of output.  Please provide some clarification in this area.

73,  K0ZN
Logged
KC0VVB
Member

Posts: 58




Ignore
« Reply #6 on: August 28, 2019, 09:15:48 AM »

200w out to a peak reading watt meter 45 to 50 watts. Carrier X 4  is 175 to 200 watts pep am.
You didn't know. Your ranger had that much snot did you. Of course a perfectly matched dummy load is totally cheating it wouldn't put that much into a real world antenna.
Logged
KC0VVB
Member

Posts: 58




Ignore
« Reply #7 on: August 29, 2019, 06:34:07 AM »

Carl thank you for your quick and helpful response. After de oxit on the switches and tube sockets and wiggling them in and out
in a gentle scrubbing manner.

I revisited my re -capping mission. though no one likes re checking caps that they just did,
i went back to C77 the 10mfd 700v hv filter choke cap at the screen dropping resistor r35 that blew off its lead that i mentioned earlier. I had previously installed a n6tlu D lab special 22mfd 450 ohm caps in series without bleeder resistors and glued to the top of the choke. This cap also shares a ground with the ac line safety caps that had holes blown through them.
I installed 2 33mfd 450v caps in series with the 2 100k bleeder resistors across each one. i flipped the ranger over and fired it up.
 
I now have modulation sounds excelent on the hallicrafters sx-100.
Logged
KC0VVB
Member

Posts: 58




Ignore
« Reply #8 on: August 29, 2019, 07:01:52 AM »

I still do not have output from the final and the vfo has been intermittent is not working right now either.

I stuck in a 3885 crystal to bypass the fvo and see what i can get out of it in to a dummy load in case the final does fire up.

Current read from the front panel meter on phone
Oscillator           15ma 
Buffer                25ma only hits 30ma with buffer control rotated fully clockwise manual specified 40ma.
Grid                   2.5ma
Plate Phone        130ma
Plate CW            150ma

Im thinking i should look for more buffer current i am having to advance the drive control to the 3:00 position and i just put in a new pot i might visit the driver tube and look for burn marks fire up the scope and try to find some rf.
any sugestions?

Thanking the eham community for your support.
Erik kc0vvb             
Logged
KM1H
Member

Posts: 5559




Ignore
« Reply #9 on: August 29, 2019, 04:11:25 PM »

Good, youre making progress. Lets stick to the crystal and concentrate on maximizing the output which is simply trying a couple of new 6CL6's.

The intermittent VFO may be bandswitch contacts, try it on other ranges which use different LC components.  Even try on CB to discern any pattern. With everything hidden in the VFO box it may very well have to come out.

Also make sure the OA2 stays lit.

More ideas later if you need them.

Carl
Logged
KC0VVB
Member

Posts: 58




Ignore
« Reply #10 on: August 29, 2019, 04:26:13 PM »

Buffer curent is at the multiplier tube V4 second 6cl6 in the rf section. Removed the LP2 filter choke i just finished gluing the capactor to. Easier to access the bottom of the 6AX5, 5R4GY, and the multiplier 6CL6.

Oh the humanity those crappy crumbly coroded leads on the 5R4GY havent seen the light of day since 1954. I fine tuned them re stripped and soaked in vinegar and salt. The terminal strips and tube socket pins at V4 had giant globs of solder covering up the remains of at least 4 previous resistor replacements. This lead me to guestion the quality of resistors the previous owners were using. Those old brown NOS ohmite little devils didnt have a very consistent carbon mixture and the newer knock off hamfest replacements dont have the correct working voltage of 350V.    

I cracked open my bag of 150 different values seven each one watt flame proof carbon and metal film resistors. Some original brown ohmite showed ok on the ohm meter but had burn marks on them.   Replaced the cracked old burned shorted ceramic disk caps with 3kv .0047. Same for the previous stage v3.

The heater line from V3 to V4 was also burned and melted through in several places of course this was replaced.  
The vfo is working.

What do i need to investigate to get output from the final it looks good no obvious signs of distress.  
Logged
AC2EU
Member

Posts: 1505


WWW

Ignore
« Reply #11 on: August 29, 2019, 04:41:07 PM »

Even if your house wiring had neutral and hot reversed, it shouldn't have caused any damage to the transmitter. It has a power transformer to isolate the line . In fact wasn't the original power cord non-polarized?
Logged

KM1H
Member

Posts: 5559




Ignore
« Reply #12 on: August 29, 2019, 06:16:28 PM »

So your saying even with these numbers you have no output?

Current read from the front panel meter on phone
Oscillator           15ma 
Buffer                25ma only hits 30ma with buffer control rotated fully clockwise manual specified 40ma.
Grid                   2.5ma
Plate Phone        130ma
Plate CW            150ma


What are the various voltages on screens and plates outside of the RF paths? The 6146 currents are about normal which is very confusing.
Start at the coax connector and work your way back to the plate blocking capacitor there should always be continuity.

Now that the VFO is working try all bands. You should get 40-50W out on the lower bands and less on 20 and up.
Logged
KC0VVB
Member

Posts: 58




Ignore
« Reply #13 on: August 29, 2019, 06:22:31 PM »

ac2eu,
Yes original power cord was nonpolorized and had fuses in the plug.The danger was it could be reversed and the hot could go to chassis. Even the antenna dow key can be energized with the rig turned off.

But every good ham calls the power company and has them spray paint the grass marking the under ground utility lines and sinks an 8 foot ground rod right out side the wall of the ham shack that the rig is connected to.

You are correct about the power transformer.  The fuses were blowing intermittently in the original nonpolorized plug before i replaces the chord.
I later discovered the T3 driver transformer out of spec which i replaced. The rig wasn't happy at all with the 3 prong plug and no fuse and a bad transformer. After replacing the transformer and installing an internal fuse i had no further issues.

I don't know what caused such havoc with the 6.3v ac line to the heaters of most of the tubes that circut must have failed at one time it seems fine now.      

Erik kc0vvb
Logged
KC0VVB
Member

Posts: 58




Ignore
« Reply #14 on: August 29, 2019, 06:50:15 PM »

                plate voltage         screen voltage       cathode voltage         plate current
6au6           360                      147
6cl6 osc      359                       84
6cl6 buff     359                       147                      7                              15ma
6146       
Phone         500                       214                                                      130ma
CW             525                       214                                                      150ma

12ax7       
first 1/2       135                                                 1.67
second 1/2  147                                                  1.45

12au7 driver 315                      347                     14




             
Logged
Pages: [1] 2 Next   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!