The AM Forum

I finished recapping this, checked it out, plugged it in and - IT Lives.  briefly. After about 10 minutes there was the most brief and quiet "pop" and it died.  

There was no smoke, no flame, no explosions. I suspect either some arcing because of dust/ dirt or some short where a wire got disarranged. Thoughts???  Until then it seemed fine. Saw plate and grid voltage, meters and lights ok, filaments lit, transformers wasn't getting hot.v12 seemed somewhat warm. It just sat there and sort of hummed.

 I checked underneath and saw nothing obviously smoked or burned.

Now, the fuse popped as it should. Turns out that I forgot to replace the fuses which were both 3 amp and had been sitting in the barn in the plug for 25 years also. (Slap to head) off to hardware store for 3 amp and 5 amp fuses which this unit uses.


and then I managed to lose one of the prongs for the plug. It was there and it vanished off the bench. (Second slap to head). I have ordered a new plug ( and will put a grounded plug on later.

K,

Get rid of that Johnson plug, and go with a modern 3 wire power cord. You can stuff a inline fuse/holder on the inside if you don't want to drill and blast.


klc

I will be doing that. I noticed that on the Viking 2 Johnson eliminated that plug. I just bought a Viking 2 CDC for my next project and there is a single 8amp plug inline with sw1. Sensible. Some research to do on that. I got because I'd never seen a CDC version.

On a Ranger 1 in restoration process had a similar event and was somewhat hard to fine. The 0.01 uF/600 V TVI filter caps sprinkled around the line input and other locations, develop cracks in the outside casing shell. The 110V will arc over from the cap, briefly, popping the fuse, but the cap looks perfectly fine! Takes a magnifying class or jeweler loop to locate the bad disc cap. Hope that may help.

Alan

Thanks. I'll order some caps and look into that. Glad it sounds like something simple.

Personally, I would find the problem first before ordering parts. Guess work doesn't always solve the problem.

    Yo'

       Wonder what flavor the Ranger is? Real early,
(Switches HV via the function sw.) Medium early (No
contact on SW4B Position 6(?)) or late model (flat
metal plate above function Sw. with 6AL5 and a 12AT7
and No contact on SW4B Position 6)

    In all cases you can pull the 5R4 and not have to
worry about HV. The 6AX5 does the LV. That soft pop you
heard was probably the fuse blowing, (They do that).

    With just the 6AX5 plugged in you should find 300
VDC in there along with filament voltage and if it
has the 6AL5 you will also find Bias voltage on the
6146 grid.

     The VFO, Buffer and Multiplier should be working
at this point, listen for the VFO on your RX. Low level
audio stages are also functional and you should be able
to see AF to the 1614 grids. If all looks good add the
5R4 back in.

     If your just plugging into the wall be aware that
filament voltage can approach 7.0 VAC on the ranger.
Measure it. They were designed for 115. Also the 300V
can go as high as 440 V.

     Good luck,

73

/Dan

it's a late model. I did replace the cord with a proper grounded cord and inline fuse. That doesn't fix the problem. I removed the high voltage rectifier, turned it on, and it ran for ten seconds on standby.  I suspect I will be spending the winter redoing the wiring.  There's a short somewhere. I will redo the posee cord and vacuum the inside. perhaps metal shavings or a wiring snippe

A shorted cap is MUCH more likely then a shorted wire.

   Yes I agree, You could pull the 6AL5 too and see if the bias supply
caps are shorted or in backwards..

/Dan

yep. found a cracked line .005 line cap. this is happening with radio on standby and high voltage rectifier removed along with accessory plug which would seem to isolate it to this area.

I replaced one obviously cracked bypass cap. at off nothing happens. on stand by it turned on, ran for a few minutes and then blown fuse. there was a flash under the 6ax5 rectifier - short - have pulled out and redone the new electrolytics I installed. Thought 2 33 u f in series were enough with 270k ohm resistors - positive end on large resistor and negative at ground on transformer as original.

large 50w resistor rusted. new one $17 at Mouser

by the way I,don't expect to have anyone walk me through this. these postings are mostly my notes on processes.
. if u want to Elmer me bless you.

Pictures please?

it's always something little. I removed the 20k resistor to get at the 6ax5 tube socket.  working on this didn't help.still a short. but then I found a bad cap- had a divot crack on the underside. On the far right of the photo.

These bad boys are all going.


Normally bare wire from positive of electrolytics to 20K resistor center cap. used 5 inch piece of voltmeter probe cable instead. flexible and no possibility of shorts. I checked the resistor and it was right on spec. 

I replaced the bad cap, checked everything over, and also checked the new fused line cord.

The line cord goes hot to one side of the fuse, a jumper to one end of the terminal strip, neutral to the third connection on the strip, and ground to a lug on the chassis.picture attached.

All looks good so I set this up with a ground, a dummy load, watt meter, key,  fire extinguisher at the ready, and  plug this into my outlet strip. This is a big metal industrial strip. All controls set to what the manual says.

On standby the unit turns on, lights up, no smoke, no drama, fine. Before it went for 10 seconds on standby and blew - which turned out to be a bad cap.

When I turn it to tune, which remember turns on the high voltage, the ground fault interupt outlet, next in line from where I have no outlet strip, trips.  The fuse in the unit doesn't blow, but the GFI does.  I tried a different outlet strip. Same deal. I saw no grid current, but a small amount of plate current.

this is a dead project until I figure this out as I have no interest in burning down my house. 
Clearly there's some kind of high voltage short in the system.

Although it is not a perfect solution, using a VARIAC on a line with no GFI is helpful. If you do not have a VARIAC, I would invest in one. And if you can, an isolation transformer is also a great investment. However, I would put a priority on a VARIAC before moving forward on this Ranger. The ceramic cap that blew on mine occurred at a VARIAC line V of just under 90 V. With a Ranger line V somewhat low it was fortuitous that when it took out the line fuse, a black soot arc trace was left on the chassis leading me straight to the cap location, like an arrow! Took a magnifier to see the exposed cracking in the ceramic of the .01 uF. Since you can turn the VARIAC up to a low AC input, say 20 V or so, you can safely measure the HV and simply scale it to the 120 V level. If the scaling does not come up to the 500+V that the 6146 is supposed to have in normal operation, you know for sure I have a definite HV issue but track it back some what safely.

There is a disk capacitor (probably .01uF) from each side of the AC line input to ground. These may take the form of a .005uF capacitor to ground... on each side of an air wound inductor. These were included, primarily, to reduce TVI. These are not compatible with a GFCI, and their effect on the level of unbalanced current to safety ground could increase when you turn on one or both of the DC power supplies.

With everything turned off and unplugged... remove both (or all four) of these capacitors.

These capacitors don't serve a useful purpose in today's context... particularly if you are using a GFCI outlet.

If you are concerned about RFI, there are much more effective ways to keep RF that is produced by the Ranger from being conducted into the AC power line via the AC power cord.

Stu

Hmm. So having those caps on the line input doesn't work with a GFCI. Why is that? Does the GfCi see it as short? I will take a look at those.

I agree. I've put off getting a variac but the time has come. I think the idea I can work at low voltages and not electrocute myself will be a Selling point to my wife.

I think they're probably are some bad caps in there with,as you note, exposed cracking. I already found and replaced a few. Q

Recommendations?

The other issue is that there are only three outlets in this room I use and the GFI is the first one in the series.  So basically all the outlets will trip this. I am thinking the moving and remodeling of another room into my radio shack/work room just moved up the priority list.



 I am giving some thought to doing a trade of this unit for a working transmitter or transceiver that does AM if I can find someone with interest.

It's becoming more of a project than I have time for.

The GFCI will trip if the current in the safety ground wire (green) exceeds approximately 5mA. The capacitors (in conjunction with the transformers they are connected to) provide lots of opportunities for current to flow from either side of the AC line (hot and neutral) to safety ground (chassis ground). Unless all of these paths are balanced to produce equal and opposite currents in the hot and neutral wires, there must be a net current flowing in the safety ground wire.  Removing these capacitors forces the two currents (hot and neutral) to be (almost) equal and opposite. I.e. neglecting unbalanced winding capacitance to ground, and capacitance between the windings that can conduct AC to ground... the AC current going into one side of each transformer's primary must be equal and opposite to the a AC current going into the other side of each transformer's primary... and there is no AC current flowing in the safety ground wire.

Stu

I always tell folks to remove the line caps, they are not needed and can cause more problems than they're worth.  Those caps act as a leakage path to the chassis and is most likely the reason the GFI is tripping.

Fred

Thank you. Thank you. I went downstairs and removed those line caps. I had already removed some of them because I took out that 117 volt ceramic outlet plug. There were other caps on the other side of those Inductor coils. They are actually almost invisible unless you look for them.

In regards to those caps - I did replace the ones around the final. There's two .002mfd and one .005mfd. These .002 caps need to handle 2000 volts so I replaced them with 6KV units. They say 1.5KV on the old cap, but I didn't want to trust 50 year old units. Complete overkill but they will be good for another 50 years now.  

The ones I pulled were actually still in spec - .0025mfd by my meter.

I still have an issue with an intermittent b+ issue. It was fine with the HV rectifier in earlier and now it blows the GFI.  Low voltage seems fine.

  That said, I fully agree that a variac and an isolation transformer are a good idea.  So I will defer any further power on tests until I get those.  I get the idea of a variac and an isolation transformer. What are you recommending in saying have both - plug the variac into the isolation transformer.

The Apache line by-pass caps use to trip my GFCI until I removed them. Then RF from the Valiant started to trip the GFCI. Then I removed the GFCI and haven't had a problem since.

Agree with all on the line caps, they are today, more of a problem than a solution and the TVI motivation is history. I guess I bought off on the idea at the time to try to keep the Ranger as original as safely possible. On the VARIAC, that alone is a key investment in safety. The isolation transformer I added as a comment in that I got involved with working on power supply switchers and it was essential again from a safety issue as well as the ability to troubleshoot. No, the VARIAC alone will not provide the function of isolation but I do not believe you need the isolation transformer in your particular instance.   

What is the worry?
If you have a problem, the fuse blows.
If you have a big problem, the circuit breaker blows.
No reason the house is going to burn down.

GFI, variacs and isolation transformers can just cause more problems.
If the high voltage blows, you found a weak point, fix it and move on to the next failure.
Those old rigs are filled with bugs, design shortcuts, and really old parts.
The only way to get it working well is to find what blows up, burns out, gets hot, reads wrong and fix it.

For testing things, I have a 3 prong cord with a fuse in the hot wire and alligator clips on all the ends.
A 5 amp fuse is what has been in there for a while.


Also, beware of some of those no name brand electrolytic caps you can get off ebay cheap, some are no good.

You don't need an isolation xfmr when working on equipment that has power xfmrs first in line off the AC supply.  The power xfmrs provide the isolation.  Isolation xfmrs may be useful when working on equipment that runs directly off the AC line without any input xfmrs, like most modern consumer products.

A variac is always a good piece of test equipment to have on the bench.  Best to get a 15 or 20 amp unit.  Over the years, I've collected probably over 30 variacs from small 1amp units to 30amp monsters.

Fred

I only pointed out the isolation transformer as another piece of test equipment that should be considered down the road, as stated in switching supply troubleshooting. On the variac, it's a handy investment and I am glad I have one (actually several). In any case, yes, the FUSE blows, great, now what. Really, its just a matter of convenience and it is a troubleshooting asset, not a hindrance. It puts me in control of bringing up line voltage as I see fit, not at the whim of some fuse blowing.  Please explain an instance where the variac causes more problems. I am sure that may be a case where under voltage devices can be forced to draw excessive current. Yes, that could be a problem. So sure, understand the circuit and apply a variac if it all makes sense to do so. QED

    Yo' Yous,


         A couple of of heavy Fil. Xfmrs back to back =
an iso xfmr.. or close enuff for ham stuff.. If fuses r
poppin U got issues.  Ranger is a SWEET rig. Do you have
a tube checker?  The 5R4 is HV, pull that...  If its
still poppin' pull the 6AX5 or whatever it is..

        Iso Xfmr is sweet but any arrangement where
ground is "Irrelevant" is cool...  Were shoes!!

GL

Please keep us posted...

GL

/Dan

Here's a thought..since it works with the low voltage rectifer we can assume that works as does LP2. Since when the HV is put on it blows the GFI that means bad bypass caps in that circuit. Same problem I just had with LV.  There is an L network near the accessory socket carrying High b+ to modulator. I wonder if removing those bypass caps would be useful.


GFI blows not the radio fuse. On an isolation transformer I bet I don't have the problem. Going to get that and a variac


I need to replace the drive pot - to do that I need to remove LP2 and the HV bleeder..maybe, as long as I've gone that far -  replace the HV bleeder and replace x11 and x12 sockets with ceramic which will make sure all the connections are good.

It's more than I need to do but its a long long winter here.

Well, fuses are cheaper then variacs, although one does not rule out the other.
On many things, the HV, bias and filaments are all on the same transformer and you might as well just power everything up with a fuse since things may not start working before almost full power anyway.
Variacs have gotten VERY expensive!

Its not unusual to have a working rig crap out in use.
With old gear you have to be used to things happening.

I do not know how many times I left the safety short on the big rigs and keyed the rig.
3000 volts at 500 ma into a short trips the cabinet breaker very quickly.

I have never had a fire, but the big electrical rated fire extinguisher is a VERY good idea in the shack, at all times.

I know, but having this makes my wife feel better about this hobby. Again, complete overkill, but I think an isopack tr-110 isolation transformer into a variac which also has an isolation transformer would be fine.

I should add that I have horrible voltage regulation here in this neighborhood. We are several blocks from a university campus of 13,000. We know when they get up and when they get home - the electricity flickers and blackouts are not unknown.

On these old radios stuff is going to flare and die - true dat as the kids say. On the good news front - a Viking 2 CDC arrived at my door yesterday. Now, shipped single boxed, by Fed Ex, and packed only with broken pieces of odd styrofoam and, I swear, the foam from a container of bacon, it was undamaged.  Try that kind of packing with a modern rig made of plastic.

Well, I got a great deal on a Scott SLRM and it was packed the same way and arrived with a big dent in the front panel and all the knobs pushed in.
Still works, but its rough on tubes to ship that way.

The isolation transformer will probably eliminate the GFCI tripping problem. But, for various reasons, it would be best to run the Ranger from an outlet that is not GFCI protected.

The disc bypass capacitors along the modulated HV path that leads to the plate choke will not affect GFCI tripping or fuse blowing (unless on of them is shorted). They primarily affect the high frequency roll off of the modulation. The stock design has too many capacitors that are effectively in parallel (too much total bypass capacitance to ground).

Since the modulation resistance of the 6146 output stage is around 5000 ohms, you want the total bypass capacitance between the modulated HV bus and ground to have an impedance of around -j5000 ohms at an audio frequency that is somewhat higher than the highest modulation frequency you expect to be using (which will be limited by other things in the modulation chain)

If you pick the frequency... where the roll off effect of the bypass capacitors is 3dB... to be 10kHz, then the total bypass capacitance should be around 1/(2 x pi x 10000Hz x 5000 ohms) = 0.003 uF.

In a stock Ranger, all the modulated HV bus bypass capacitors add up to more than .01uF (including the effect of the plate blocking capacitor that feeds the pi network).

Therefore, you should remove at least half of them (e.g. C66, C67, C83, and C48)

Stu

That seems sensible and was the direction I was headed in.  I am putting this on hold for a while until I get a variac.  For those interested I unpacked the viking 2 CDC this morning. All intact, very clean too and bottom,  no obvious signs of smoke, damage, or Gus with the Golden Screwdriver having visited. All the tubes even made it without breakage. Amazing how clean the inside is. I was expecting it to be much worse.

  Anyone interested PM me and I'm happy to share more.

Thanks. I have a variac on order.  Removing those bypass caps has stopped the ground fault tripping.  This morning , feeling in a mood to take a risk, I fired this up and it operated in tun for several minutes - until there was a short caused by a stray piece of wire that was grounding in the chassis. Far in the back where it had escaped inspection and the hand vacuum. I was seeing about 30 ma of osc current when that happened but nothing else.  There was no obvious indications of issues e.g. Smoke, fire, hot transformer.

 Removed that, replaced fuse, and tried again with the 5R4 removed.  Everything lit up. I am thinking that, basically, everything is OK. The Operating manual is non-specific about the warmup time. I'm thinking three minutes before I should be seeing plate current? I am very hesitant to do anymore with the 5R4 installed and at this point I am stopping until I get the Variac and can check the voltages properly. I need create some replacement cabinet bolts and maybe repaint the front of the VFO which is terrible.

   N9AXL,

            If it's not "Smoking" with the 5R4 pulled, there a lot
of checks you can make.   I got one on the bench now, Far
from "Stock" but still a Ranger at heart.

            First off "we" need to know what Variant of Ranger
you have.  To determine this:

       Does it have the Keyer Sub Chassis above the
       Function Sw. ?

      If so, does it have the Taps from the power xfmr
      to supply the 6AL5?

       Looking at the back of the function switch at the
       rear wafer, does it have an "Intact" pin 9 position?

       With the Meter SW in the "GRID position" and the
       CRYSTAL/VFO Sw. in the "ZERO" position, can you
       find any indication of grid current?

Pin 6 will not be there in all cases, so continue to count
CCW from pin 6 to pin 9. It should be the bottom of a .51
ohm Ip shunt.  In ALL cases the lug will be there, in some
cases there will or will not be an actual contact that
reaches the wiper on the switch part.

       Direct answers to the above questions will help
us help you.  Also, Whats your name?

Please keep us in the loop.

73 and GL

/Dan

There is only one 6.3 volt winding on the power transformer that supplies 6.3 V AC either directly or through the 9 pin accessory socket in the rear.


     
Pin 9 is used as a tie point terminal. It has no internal switch function. Pin 6 is just an extra terminal. It has no switch function.

  

Pete,

 Yes, The taps I'm referring to are on the sec. of the Power XFMR,
lower than low voltage taps, Labeled (Y) on the schematics.


     I have never seen a ranger with any hardware in the "6"
position of SW4B and I've seen a lot of em!

     Pin 9 of SW4B routes Modulated HV somewhere, I can't
recall where right now, but there were and still are at least
3 versions of Ranger's in existence.  Let alone the Ranger II.
They did try to get away from HV switching via the function
Sw.

     N9AXL may be new to this stuff, I have a little tiny bit
of familiarity with it. Just trying to help...  U ?

/Dan

After roughly 1956/57 Johnson supplier a transformer that had those additional taps for the 6AL5. With earlier Rangers, the keyer modification included a voltage divider network that at one end connected to the plates of the low voltage rectifier and the other end connected to the cathodes of the 6AL5.

Thanks. I've done smaller projects -- restoring DX-40 and Hallicrafters receivers - but this is bigger.  This is the later version with the keyer deck.  I haven't examined the switch as suggested, but I can do that this week and report back.

The summary on this --for those not wanting to read the whole thread -- is I got this from a barn sale for about $150 and was told it had been sitting for 25 years.  It seems intact with no mods like PTT and is a kit build judging from the screws on the tube sockets.  I have (1) replaced all the caps especially the electrolytics (2) replaced the power cord with a grounded cord  and also the lower voltage rectifier tube (3)replaced a few caps that either had failed or looked like they would fail e.g. cracks  4)removed a few bypass caps to eliminate tripping on my ground fault interupt outlet. (5)basic cleaning of the interior and exterior, removing rust off the ground lug, etc. 5)did a basic inspection of the wiring, ect. and see it appears intact.  One or two of the connections to the HV and LV tubes seemed iffy so I resoldered them. 6)I have left the VFO alone. Judging from having to push on the tuning knob the planetary gear seems shot.  I plan at some point to build a digital VFO to plug into the crystal socket and use in place of the built in unit.

I have on order a new 20K bleeder resistor.  This checked out OK, but I thought it should be replaced while I have the rig open and the existing one can be a backup.  I also have a new driver pot which I also plan to replace since the bleeder resistor, etc needs to be removed anyway.  I'm debating replacing the tube sockets with ceramic, but haven't decided whether that's worth it yet. 

The goal here is to get this working on 40 meter CW in tandem with a Hammarlund HQ-170c. If I can get it to work on 80 meter phone that's a plus.  The overall goal here is to build a classic 1950s operating position with a Hammarlund HQ-170c flanked by a Johnson Viking (for CW) and a Johnson Viking II CDC for phone.  The latter unit I have and it is next on the bench after the Viking is done. I'm also rebuilding a D-104 microphone for which I need a new element and the appropriate connectors. 

   Hey Man,



         As far as your VFO, it could just be the shaft coupler.
Nothing wrong with them once you get him going. Did you get
the chance to make the checks I posted about 5 post's up?
RE: The version of Ranger, Grid drive, and such. Or are you
waiting for your Variac. Probably a wise decision.

   I have been desperately trying to finish up my
"Problem Child" Ranger as well.  He is all Modified per
the WA3DSP write up.  I posted on this about 5 posts up
and will attach a PIX to this post. Amazing how "Bare"
the under chassis side is once you rip out all that crazy
filtering, eliminate the Driver Xfmr, switch him over
to modern caps, and relocate the LV choke to the top
of the chassis.


        I also attached a pix of a real EARLY Ranger
Function Sw.  Showing the original configuration of
SW4B-Pin 9.  In this pix Pin 9 is the one with RED/WH
wire attached to him.  Its kind of hard to see but
you'll notice that he has a full contact. You can find
these in one of three states. 1: A full contact as shown,
2: A partial contact where the sw. was modified just
to retain the "Wiring Lug" OR 3: A burnt, melted thing
there that used to be a full contact.


       Since your Ranger does have the keyer board
you should also find an additional pair of leads off
plate Xfmr. to power the 6AL5.


      Glad to see your pushing through all the BS that
comes with old Hammy Hambone gear! It will make you a
better Person!  You'll certainly have better radios.

73

/Dan

This appears to have the Johnson PTT installed correct? I see part of a relay on the left side of the picture I think.  Didnt get to the Ranger yesterday since I had to diagnose audio issues in my FT-221 which needs a new PB-1499 audio board. maybe today.

  Yes he does, Good catch...

73

/Dan

This is confusing because there is another relay in the back next to the microphone jack.  Perhaps this has some other function like a tR  switchOr the Johnson PTT has been disconnected and the relay is for a newer PTT ?  In my case I took the 115 volt ceramic output Jack out that powered the Dow key relay in favor of an external T/R switch. 

This is confusing because there is another relay in the back next to the microphone jack.  Perhaps this has some other function like a tR  switchOr the Johnson PTT has been disconnected and the relay is for a newer PTT ?  In my case I took the 115 volt ceramic output Jack out that powered the Dow key relay in favor of an external T/R switch. 

   Sorry for the confusion, the PIX are of
2 diff rangers, the SW4 pix is just another
Ranger that happen's to be here.

   The "Bottom View" pix is the Ranger I modified
per the WA3DSP write up. There are actually
2 relays on the back apron. 1 switches HV and
LV. The other is for TX light and osc. keying..

    Amazing how cool a Ranger runs with the HV
and LV removed from everything except the VFO
and V3... SW4B brings up LV to the Audio stages
only in the PHONE pos.

73

/Dan

Back at this after a month - busy hiring new employees for my business - I replaced the 20kohm bleeder resistor and started checking my work.


I see that at the beginning of this I replaced c78 a 30mf electrolytic with a 20uf I had in my stores.  It connects positive to the terminal strip with a .005 cap and a 27kohm resistor - upper part of photo. I ran the ground side to a screw on the chassis. I see elsewhere people have replaced this with a 47mf cap. That appears to be the correct wiring as I read the schematic.  The low B+ seems to be working.


As far as I can tell there are no obvious shorts to ground or other issues shorting the High B+ - these are two separate circuits.

Advice? It seems like this part is wrong and should be replaced.  But that doesn't solve my high b+ issues - again needs a variac but that money this month went to replace the heater in my car - a necessity for winter. Maybe next month. Remove all the tubes except the rectifiers and bring everything up slowly and see what gives.

      I have been screwed by two nasty shorts
on a Ranger..  1: Those crappy filter coils
touching one another.   2: That RF choke
on the terminal strip for the VFO being bent
so far down that he hits other pins or chassis.

     Do you have an ohm meter?

Yes. I think I have c78 connected wrong. The positive end Should be on one side of lp2 correct? 

yes..

thanks. I think, somehow, I added an extra electrolytic cap to this.  I count 5 in the assembly manual - the three dual caps c90 c50 and c59, c78 in the front middle, and c77 the high voltage cap

In my unit I have the c50 c90 and c59 replaced, c78, and c77 - made of two caps plus the resistors.  That leaves an extra 30uf electrolytic cap which has no business being there. This makes six. See photo.

back to the assembly manual to check everything. Am I thinking this through or perhaps my copy of the manual is incorrect.

K,

You may wish to move the 20uF cap away from that wire wound space heater.....


Somewhere, I think maybe Electric Radio, someone removed all the original TVI coils and replaced them with more modern coils. Saved a lot of space for other things.......

klc

My first issue her is I have a resistor marked 20000 oh mite which I think is either r6 or r38 connected to terminal 2 of x16.  There is an identical resistor connected from x15 to x16. But I can't find these values in the parts list. Where does the other end of the first resistor go?  A parts replacement of some sort.

Second, the instructions are quite clear to connect terminal end of the HV bleeder resistor to pin 1 of 5u4.  This makes no sense since pin one of this tube is connected to nothing. Assuming that pin one is the first pin clockwise from the tube notch.  There's a pin directly in front of the notch which I think is eight.

Back to tracing the cabling. There was never any connection from the HV bleeder to pin 1 so I begin to wonder if this ever worked in the first place in 1958 which explains it ending up in a barn. 

Octal sockets do not have a pin in front of the notch/keyway, one on either side, pins 1 and 8.
Sometimes unused socket pins are used as tie points...

The sockets usually have numbers on them you can see with a lighted magnifier.

Thank you.  I found a very light number on pin 6 a red wire and counted counterclockwise to find 1. There appears to wiring connecting to pin 1 so this makes sense and this comforms to the wiring diagram.

there are two 20000 ohm resistors on the terminal strips. One is disconnected and I need to find out where it goes. Where it is connected now on the end of the bleeder resistor is wrong.

I removed the 20 mf electrolytic cap as I think it shouldn't have been in there to begin with.

I'm finding the assembly manual has ambiguity and was clearly written for people who knew what they were doing. You must read every paragraph carefully.

  read page 29 paragraph 3 in regards to "temporarily" putting the positive end of c77 to terminal 2 of x15. It never says another word about where you should permanently attach the positive end until the end of page 36 when it says to connect it to the bleeder resistor.

For us the end of the bleeder resistor, 50 years on, is the "normal" position of the positive end of c77.  I also think this may solve my HV issues once I put in that jumper. Yea!!!

   Hello, Hello, Check check, Is this thing on?


/Dan

I finally got set right on this deal when someone emailed me the following schematic. What has been confusing me is the remnants or an attempt at a push to talk circuit - which explains the 20000 ohm resistors and the mystery electrolytic cap - there was no relay which would have been a tip off. Seems like they started the project and didn't finish it.



I can now simply remove these resistors and get on with checking the wiring. I wonder if having this half completed circuit has been a partial reason I have been having HV and LV issues through this whole process?

I am beginning to wonder if this was a kit that was never really working correctly and the original owner finally gave up on it?

The PTT information and the schematic you posted is in the Ranger manual (pages 19 and 20).

Thanks. It was in the operating manual and I was working from the assembly manual.  As I said the power supply appears to be working which is a major step forward. 

"  the power supply appears to be working "




Keep one hand in yer back pocket and use your Jesus Stick on the caps.


klc

   I think you only got 1/2 the story.. You will need to add
jumpers to SW4 to restore the unit to stock.  IIRC the "R"
was only there to accommodate the obscure relay COIL. There
was a page of "Steps" to preform along with the schematic.
I'll post the whole story when I find it.. Again if IIRC
I think the contacts of the relay replaced jumpers on
the Mode Sw.

   If U still need a drive control PM me..

/Dan

The jumpers and everything was there. It looks like whoever did this followed the paperwork. 

I have found that R38 three 33k in parallel, which was supposed to be 11k, was actually 111k.  That may explain why I was getting no buffer current?

 I have new resistors on order so I will replace that and check the rest of that circuit this cooking weekend when I have time. The power supply circuits appear stable. The rig turns on and stays on with no issues. I get oscillator current. The filaments light on everything.

I fired this up using the tuning procedures in the manual on 40 meters. For a few minutes it appeared I had normal readings.  Then it stopped. In tune I see no buffer current. In phone I see 20ma oscillator current and 200ma plate. Plate current will not dip.  

I did check the buffer variable cap and realized it was binding. This was corrected - it needed an oiling and rotation - and is now moving freely.


I am suspecting V4 or v3 6CL6. Perhaps one or both was weak and simply gave up the ghost when normal operation was expected of them?  This did spend 25 years in a barn which I suspect wasn't the best environment even for a rugged vacuum tube. I replaced both tubes and now see with vfo turned to zero about 1ma buffer current on tune with the drive turned up all the way.  On phone the plate current shows full scale and it can't be dipped. I see no grid current in any case.  I wonder if the drive control needs replacing?

Tubes do not go that way.
Maybe a dirty switch contact or tube socket, or a cap failed.

Probably. I replaced the drive pot.  It needed doing anyway.  For those interested there is a black wire (left), green wire (center), red wire(right). If you lose the interior nut behind the panel there is a work around- wrap the pot in electrical tape, put a grommet in the chassis hole.  This with a knob will hold it in place. Better than having to remove the entire panel. Don't ask how I know this - please. 


Now  im back to no buffer current.  I think I'm putting this project away for a while and doing something else.  It was a great learning experience having never fixed anything before. Getting it to turn on without drama and do anything was an achievement. And I see that the wafer on the VFO/Crystal/zero switch has developed a crack. given that's made of unobtainium it may be a while before this gets finished. and that will require removing the entire front panel.

Locate the two red wires coming from the plate transfomer and connect them together at the HV rectifier tube socket, and then connect that junction to ground. You will have plenty of grid drive after that and not have to mess with the buffer or drive level pot.