OOPS!!

My turn for a blunder!!!

You are absolutely right. The Hz output is on the regular filament string. I was thinking about the output and damper when I posted that. Dork Me!!!

Glad to hear that the set is wired correctly...I was thinking that if the heaters of the damper and horizontal output were, indeed tied together by mistake, that could have contributed to the failure of the transformer... things could have been very exciting if the heater shorted to the cathode on the damper.
BTW, the RCA 9-T-240 used a 5V4G for the damper, hence the extra 5V 2A winding on the RCA transformer.
jr

I think the RCA transformer is going to be physically larger, I don't have the 9-T with me here at work but I have one from an 8-T and it measures 4 1/8" X 3 1/4".

I'll have to check the 9-T but I think they were the same size.

I also have a Motorola TS-9 chassis here and the transformer seems to be pretty close to yours at 3 3/4" X 3 1/8".

Electrically I don't know, anyone have specs on that one handy?

Well, the Sams for the TS-9 is somewhat confusing. There appear to be 2 flavors... one for the sets with 5U4 and 5Y3 combination, the other for sets with 4 25Z6 rectifiers.

The 5U4/5Y3 model shows as follows:

730 Vct @ 2.23A !! that can't be right, must be 223 ma?? :scratch2:
460 Vct @ 58ma
5V @ 3A (for 5U4)
5V @ 2A (for 5Y3)
5V @ 2A (for 5V4G damper)
6.3 @ 7A (for most tubes)
6.3 @ 0.6A (for CRT)

Stancor P-8157, Chicago TP-450
hope this helps,
jr

OK, I measured the 9-T transformer and it's 3" X 3 3/4" across the bolt centers.

The wiring is pretty shot and hard to tell one from another but I suppose it'll be easier once the cover is off.

It's rusty on top but I see no evidence of overheating.

Anyways it's yours for shipping if you want it, I can probably fit it into a Priority Flat Rate box for $10.70.
It'll be close on the 5 1/2" side of the box but If I put some nuts on the screws and pad it with stiff cardboard they'll have a tough time damaging this hunk of Iron!

I think it will fit. A big public thanks to you.

Bruce

Cool, I'll ship it off to you tomorrow sometime.
You can pay me with PayPal when it gets there.

Someday I want to fill one of those flat rate boxes up with Lead wheel weights or Iron bars and see what they say when I want to ship it flat rate. :D

I'd sure hope my box of NOS 2A3's is not traveling under your lead wheel weight/Iron bar box!!! :D


I cant reply again until tomorrow afternoon. I gotta to to work in the morning, (kicks dirt with toe) I gotta go to bed. :(

It's now Friday.

The transformer has arrived. Thanks, Eric! I'll be sending you something on Monday.

Now for the fun task of identifying wire colors, and replacing brittle wires, painting, etc, etc...

It has begun.

Waiting for a Mouser catalog to arrive.

Nope. It's for damper winding.
Bill Cahill

Don't connect your damper to six volt line!
You'll blow entire set!
That has hv pulse on it!
You MUST use that five volt winding the original used.
Bill Cahill

Dont Worry, Bill.

The DuMont has a separate filament transformer for the damper (a 6W4GT) on this set.

The 2nd 5v winding on the RCA transformer will not be used.

While I'm posting, any tips on getting the wire color to come up out of the filth on the current wires in this RCA transformer? I wet them with water and dried them with a rag. They still look mostly black.

I was hoping perhaps the colors might be more visible inside the transformer, or at least they might be numbered.

Resistance checks should identify the primary's, wouldn't they have the highest resistance?

I think they were the smallest pair of wires but I can't remember.

Im going out to dinner tonight. I'm going to pull the shell off the transformer tomorrow...carefully.... And we will see what we can see....

That black color is tar.
I'd check voltages, first.
Hint.
Five volt colors for 5U4 should be yellow.
Plates, red with yellow tracer.
B- brown with black tracer.
primary: both black.
Regular six volt two green.
Other six volt would have been two blue.
You could disconnect filament pin from cathode, install a 6AX4, and, use that.
Bill Cahill

You could place that 2nd 5V winding in series with the primary, to add approx 5V to the 120V primary's rating, to compensate for today's higher voltage powerlines. You'll know if you got the phasing correct if the old primary has approx 5V less voltage than your powerline has. And if the various secondaries produce about 4% less voltage than before. If they go up in voltage, reverse the 5V secondary lead connections.

The blackness is not tar. In fact, the wires are just cooked pretty good. We got the cover off, and I'm getting an expert with colors (my sister) to help with the ID. I think I found the primary wires. Im absolutely NOT connecting anything to power until I know whats what. Ohm meter? I love mine.

I wasn't sure about the wire colors. I've replaced a few transformers in old Fender, and Magnavox amps, and the color codes were the same as what you said.

All of the tubes in the set are now testing good. Now, we wait for the Mouser catalog. I have a few capacitors laying around from other projects that I can replace in the meantime.

This may take some time. I'm having to go to work this afternoon and replace a $1000 4,000 watt xenon lamp in a projector. Happily, for job security, I am the only one there that knows how to do it.

Progress!

I have a complete RA111 chassis on hand for parts. It uses the same power transformer as the RA112/113.

My first Mouser order got cancelled, due to alot of substitutions on their part. Not a problem, though.

I will install the transformer and leave out the rectifier for now. Replace the 7-8 electrolytics, and go from there. I've gotten alot of PM's about DuMonts and quality.
I look forward to seeing the soft glow of the chassis... minus B+ for right now.

The RA111 chassis has a fuse socket mounted on the chassis. It is much newer than the chassis. I will be fusing my set, too. I sure dont want anything like this to happen again. 2010 has been my year of bad power transformers. But, its also been good as I have found replacements for them. I have my friends here at VK, and ARF, to thank for this!

More to come, as it happens...

Pulled the old transformer and rectifier tube socket as an assembly today. Found one side of the rectifier tube socket had been very hot at some point and had broken away. Installed in the set, I couldn't see this side of the socket. Thankfully, the doner RA111 has the same transformer/rectifier socket mounting so I reinstalled the transformer using this mount. While in there, I found a single wire that had almost no insulation that was cooked thoroughly. Apparently this wire had a long time working while damaged in this set, as there is rust in several places along its run. Turns out that it runs from the power interlock to the back of the switch.
I attached the new wire to the end of the old one, and gently pulled it through under all the other wiring from the switch back around the side of the rectifier tube socket and up to the interlock. It is working.

I'm not applying any B+ anywhere on this set until I get a load of capacitors replaced. I did turn on power thru my variac just to see what it would do. It powers up fine, all tubes are lit, so I left it running this way for a little while just to let the chassis get somewhat warm, and to see if this transformer is OK, which it is. I have to re-solder the transformer filament winding lead after I move some wax caps out of the way. Someone in the past has done some not-so-pretty repairs in the past around this area of the set. I'm fairly sure that this transformer has been replaced before. The one I removed has the same part number as my replacement does. I've found some snipped wires at solder connections with the same colors on them as what the transformer has. I sat here looking at the tubes glowing in the chassis, when...

Suddenly, POP!

I looked quickly at the chassis while fumbling for the switch on the variac. I watched one of the 2 flat capacitors connected to both sides of the power line to ground slowly open up like a clam. Cut power, and cut it out of the circuit along with the other one. The Riders schematic doesent show these caps, so I will leave these off, unless instructed otherwise.

So, here we are. It lights up. All the controls are cleaned except for the tuner itself.

It's all ready to run after the cap replacement.

Some new pictures of the switch wiring, the front of the tuner dial, and some of the transformer with most of its wiring finished, especially on the rectifier socket. You can see the exploded capacitor, and its undamaged, but very warm sister, both since removed.

Also, in the first pic, you can see the routing of the very yellow replacement wire snaking thru the chassis under everything else there. Notice the rust. The wire I removed was thoroughly cooked with very little insulation left.

dumont transformer
 

Hi did you use the transformer I sent you for your set?

It was the one you sent me. It happened fast.

If you decide to replace the two line-to-ground caps, use type Y2 safety caps, designed to fail open. Those caps are there to reduce RFI coming in over the power line. One source is justradios.com.

Yes, but, that was primarily from sources such as Car generators, who has one now?, and, diathermy machines. Used yours lately?
I find I have virtually no problem without my caps. And, if the resistor is still there, remove that also.
These line caps only make the chassis more of a shock hazzard.
Bill Cahill

We have a new source of RFI that will eventually be forced on us. Compact Fluorescent lamps. They're not too bad, but they do bother some of my radios.

John

There are many sources of RFI today, CFL's as mentioned, light dimmers, phone chargers, computer power supplies, not to mention garbage that comes in over the line from the neighbors. I generally put one cap from each side of the line to chassis, after the switch, so they're not working when the set is off. No resistor involved. Granted, interference may be more noticed on an AM radio. TV with FM sound may not be as affected, but possibly AM video could be?

I ordered 20 electrolytic caps for the DuMont just now. Planning to order Sprague Atoms, but didnt. I did buy 105 degree C capacitors, though.

I have found the HV caps for the doubler circuits, too. Not a bad price, either.

And now, we wait...

My other projects, the Maggie twins, are next!

I started the afternoon by carefully oiling the shafts of the inductuner with turbine oil. I gently rocked the tuning knob shafts and they let go suddenly. Now, the tuner is turning smoothly.

I replaced the majority of electrolytics in the power supply. Installed the 5U4G, and pulled the horizontal output tube. Brought the set up slowly over 2 hours this evening. At around 80 volts, I was hearing noise from the speaker!

At 90 volts, I could hear the signal I was feeding into the phono plug through the speaker! I continued to bring it on up. Started seeing gas glowing in some of the small tubes. The tuning eye is green. Nothing wrong with the power supply. The new transformer is not getting hot.

Finally, at 110 volts, I tried feeding a signal from a VCR to the antenna input. It took a few minutes of adjusting the tuner around ch3 before I suddenly heard the video tape I was playing! Adjusting the fine tuning brought the sound in loud and clear.

I dont have the HV caps, yet. I was feeling brave, and installed the horizontal output, and turned it back on, slowly. Heard a couple of arc pops while taking a fast reading at the anode of the CRT. 3KV. Turned it back off, and pulled the hz. output again, and turned it back on. It has been sitting here playing audio for about 2 hours now, total. I think I will have video, because when the video is playing on the VCR, I can see the brightness of the slight gas in the video output tube change as the picture changes on the movie.

I've been running the chassis for the last week or so without the 5U4G installed just to help the set dry out a bit. With the tube installed, the whole chassis warmed up and I was treated to some dampness smells that I havent noticed before.

I need to rig up a stand for the chassis so I can pull it out enough take readings with everything connected.

I'm not going further until I get the HV caps replaced. During the very short time that the hz. output was installed, I could see the filaments in both of the 1X2's glowing, and touching a screwdriver blade to the caps of them produced a tiny arc.

In the meantime, the electrolytics that remain are not overheating. I will replace them, but I've got other things to look at until I get the HV parts.

I sure didnt expect to hear sound thru the antenna input this fast!

Bruce

It's been a long time since the last post. I'm trying to clear out my house, garage, and workshop of unnecessary clutter, and I'm making some progress. I also aquired the RCA CTC-7 set, and got sidetracked with it for awhile.

I've replaced more electrolytics in the DuMont, and a few of the wax capacitors, so far. Also, got and installed the 3 HV capacitors. I've now got 12KV!! It's slow going, though, as I've not seen anything on the CRT screen, yet.

I'm seeing that I'm not getting anything from the brightness control, which is on the -55v line from the power supply. Gotta pull it back out to check. I'll also check out the selector switch to be sure everything is working at the TV setting. FM works, as does the phono setting.

The CRT voltages are mostly there... 300v, filaments, but nothing on the 65v cathode, or the -32v line at the grid. When I pulled the CRT socket completely, nothing changed, so I'm sure the CRT isn't pulling things down.

All I had to check the CRT on is my Sencore TC-109 tester, which shows the tube emitting at 96%, and takes almost 40 seconds for the emissions to start dropping after cutting power to the filament.

Any comments are always welcome. I've done just a few repairs on tube televisions. I made my loot on solid state!

Do you have the both -55 and 75v supplies on the outside terminals of the brightness control? Make sure V209-B(DC restore) tests good. Check the 100k resistor on the CRT cathode?
I'm referencing from the Riders schematic.

I would not expect it to work normally until you replace all of the wax paper capacitors and electrolytics.

Trying to troubleshoot problems while it's still full of bad capacitors is not a good use of time.

Phil Nelson
Phil's Old Radios
http://antiqueradio.org/index.html

Agree with Phil on replacing caps first. I'd overlooked that you hadn't done all the papers.

I'll be checking more things here when I get it pulled back out of the cabinet. I'm not expecting a crisp perfect picture, here. I'm just hoping to see something.

I cant leave the set apart when I'm not working on it. It's not in the workshop.

V209 6AL5, is new.

I'd check all resistors and caps around V209B, including the brightness control. You do need to have the correct DC bias voltages on the CRT first. Then provided your horizontal and vertical circuits are working, you should see some sort of a raster. You did mention you have 12K of HV, so apparently you have horz drive and your flyback is working...

I've got to see some kind of a raster before I can truly continue. My older CRT tester got hit by lightning last summer, and I'm going by what I can find with the CRT function on my tube tester. I have no B/W tube sockets for my B&K color CRT tester.

I'm in no way going to junk this DuMont. I'm suspecting an open somewhere.

Vertical and horizontal are both working. I can hear the vertical pulses in the yoke, and when I adjust the vertical hold, I hear the pulse rate raise up and go down. I have all intentions to replace every capacitor that needs it.

I'll check around V209 and let you know what I find.

Getting the electrolytics done was the first priority after I replaced the power transformer.

I truly appreciate everything said here.

You could always make yourself up a set of universal clip leads for your color B&K.

I woulduve done alot worse than back hand em!:yes:

The only reason I noticed this set was because I heard him try to sell it to another customer using the aquarium approach! When I saw it, I knew it had found a new home.

Hmm. Good idea!

Removed that resistor night before last. It was open. Didnt look burned.