The scene from our back-40 yesterday as the Worthington Fire grew quickly to over 500 acres. It is not yet fully contained today. Temps over 100 deg. F.,  humidity  in the single digits, wind gusts ~15 mph.

This post is a continuation of the "Farm Radio" post below.

When I purchased this radio off of P-Bay things were Covid-slow. So I decided to do a more in depth restoration of the chassis. Little did I know that Bill Reid was going to donate the rest of his collection - about 3 truck loads, but, more on that later.

You usually see this cabinet with chassis #5516 which would make it a model 5-S-127, one of my favorite radios. Those are not uncommon. I think that the radio was as popular at the time of manufacture as it is now. There seem to be quite a few around, but popularity has driven up the prices above comparable radios by other large manufactures. 

Above are a pair of 5-tube AC powered chassis. There was a lot of variation in this chassis construction. Even for the 60hz models, there were at least 2 transformers, at least 2 different speakers with different field coils which also created some circuit differences. So if you work on one of these be sure that you have the appropriate schematic.

Other than the components, there was also a painted and a plated chassis that often has green, rusty patches like the one above.

The battery powered chassis has a different layout than the AC versions. Somehow I failed to take a proper "before" picture prior to the removal of all of the rusty/corroded components. With everything removed it is easier to see the extent of the rust above. Note that there is no cutout for a power transformer.

I don't like to paint chassis that were originally plated. Besides the issues with ground points being corroded and subsequently , painted, I  just  don't want a radio that has been altered in that way. SO it was time for MORE FUN WITH CHEMICALS AND ELECTRICITY!

 I had a disk brake hub that was keeping a tarp from blowing away. If you are going to de-rust steel a steel anode is necessary.  NEVER use stainless steel. 

​The white powder is washing soda, easily found at WM.

Just add water, hook your chassis to the NEGATIVE lead and suspend it in the solution, not allowing contact with the  steel plate.

I am avoiding using the term "Anode" here since it can be confusing, ESPECIALLY for a person that is accustomed to working with vacuum tubes. If you want to get it straight in your head, you will have to do some reading and I did not want to bore you here.

The result will be a stream of bubbles coming off of the rusty chassis and a nasty looking film of orange gunk will float to the surface eventually sinking to the bottom.
THE GASSES EMITTED IN THIS PROCESS ARE COMBUSTIBLE  and that is why THIS SHOULD ALWAYS BE DONE OUTSIDE. And, if you are not absolutely sure about the technique DON'T DO IT AT ALL.

Remember when Circuit City  went out of business? I went to the liquidation sale, late in the day. There I found the power supply that had been used for the car radio display and managed to acquire it for $25. I was not sure what I would use it for at the time - but now I do. You need a LARGE DC supply for rust removal. It does not need to be well regulated - or regulated at all, but you will need a few amps and 12V is a good voltage. You can use a car battery if you missed the Circuit City sale.

Then all you have to do is replate the chassis - NO, not with copper, with nickel, then with copper. Acid copper (bright copper) plating solution is too acidic to plate steel. Instead it will just turn black/nasty and corrode some more.

You might want to fill some of the pitted places with solder - easier said than done. Solder works best on the nickel plate rather than the bare steel. Use an iron - NOT a torch.

I really don't do this all that much (and for that reason, take my advice with a grain of salt - like you usually do). I was happy with the results. Kinda' PINK, but it will be the color of an old penny after a while.

Did I mention having to remove EVERYTHING from the chassis including all of the riveted components? Well, now you have to put it all back!

Some people use bolts or screws. I use rivets like the originals, besides, isn't hitting a chassis with a hammer something you have often wanted to do?

​BUT WAIT - THERE'S MORE!

Almost every metal component on these chassis are plated with something. The tuning cap is plated with nickel (not the aluminum plates) and the IF transformer cans are plated with zinc. Talk about dissimilar metals! I think that the cans needed to be plated to avoid corrosion of the base metal which seems to be aluminum. 

After dealing with the nickel plated components I moved on to a new challenge - zinc plating - which is supposed to be easy(er).

Above: IF and RF coil covers.

As found
Sanded/cleaned up
Replated

​Keep in mind that I am showing you what I did, not telling you to do it.

​Below is the configuration I used for plating zinc. The zinc foil, which is very soft/bendable, was purchased for very few $ off of Amazon. The plastic bowl I borrowed from Sue. I don't think that she will miss it - - or want it back. You must use a variable voltage power supply. So the big sucker pictured above will not do.

I easily formed the foil to the shape of the bowl insuring electrical contact for my + connection. The part was hung off of 14 ga. copper wires and the little pieces of paper insulated against shorts and subsequent explosions. (see gasses are explosive above)

At this point I should mention that I performed this process on the 5516 (AC) chassis, pictured at the top of the post, as well as well as the battery powered chassis that was going back into the cabinet. I have found that once a process is started it is easier to continue rather than restarting (and relearning) it later. So the pictures of re-plated items are a composite of both chassis.

The IF/RF transformer cans came out a dull grey, just like I expected them to be. During the plating I noticed that the zinc could appear more like a galvanized finish if I deposited less zinc on the base metal. This included the wavy lines and markings typical of a galvanized surface. So if you like that, stop sooner.

Some more notes:

I needed a dielectric to transport zinc ions and water alone will not do - maybe salty water, but I did not try that.

I saw somewhere on the internet (source of all wisdom) that a person could use the washing soda used in stripping the steel to make a solution. I tried this. One way to see if your setup is working is to monitor the amperage on your power supply and watch for the small bubbles. There were bubbles - and bubbles - and nothing else.

So I decided to ditch the washing soda water for clean in which I deposited about 2 tablespoons (use plastic spoon) of battery acid (sulfuric acid) - - do I really need to tell you not to do this?   Anyway,  now there was some action. At first I needed to set my supply at about 15 volts . BUT, by the time I finished 4 of the cans I had dropped the plating voltage to about 1.5V.  (that is one and a half volts)

​I suspect that the process formed zinc sulfate in the dielectric which encouraged the transfer of zinc to the plated surface. Had I maintained the 15 volt initial setting, I would have destroyed the can and the foils and - you know - sparks, fire, explosion. So if a person was to try this - and I know that you won't - careful monitoring is absolutely necessary.

​Zinc sulfate is a component of fertilizer, but I would not pour this stuff on the flowers. I dispose of chemicals responsibly.

Both chassis above. I could have plated the tube shields s well but they were not in bad shape. This is a good comparison of the DC and AC powered chassis.

Above and below are the before and after pics for the AC chassis

It should be noted that it is difficult to "throw" the plating into the corners of the chassis. And that I stock the original Zenith caps for those chassis that have lost them.

Thanks to Harry L. for a lot of those old caps.

Above and below are the before and after pictures of the DC powered chassis

Now, back to specific differences between the AC and DC powered radios.

The cabinet used for the 5-F-134 is different than the one used with the AC chassis. Note the 2 wooden brackets near the top of the cabinet. These are used to slide in a vibrator power supply which would have used a 6V battery as a power source. The brackets, along with some other modifications, make the battery radio cabinet heavier than the AC chassis cabinet. 

I had always thought that a radio with the brackets and without the vibrator supply was simply missing that supply. But, no, there is another configuration for storage batteries, a setup that would be familiar to users of mid 1920s battery radios.

On this DC powered chassis there are 2 plugs on the top surface. One is to plug in the vibrator supply (right) and one is for the dry-cell batteries (left). On a radio optioned for dry-cells there are 2 heavy jumpers installed in the vibrator supply plug - see above. In this configuration a cable was provided to plug into a dry-cell assembly, A, B and C cells.  So, on this chassis, the A supply was 2 volts and 2 volt tubes are used. The radio works well with about 140V on the B supply. A C- supply could limit current consumption of the final audio output tube.

​So it is perfectly normal to have a radio that does not use the top mounted vibrator supply.

Of course, while I was having all this fun the lacquer was drying.

It looks even better in person.

I have already started on some of the radios donated by Bill and some of those will be up next. Along with the old radios is some tube-type audio equipment, which I find interesting and useful. Though I have restored a lot of tube-audio gear, I have not posted much about them. Maybe we'll get into that next time.

Russ

 - -and thanks Bill for filling up my shop ;-)

 - or What to Listen to When the Power Goes Out

After all, we do live on a farm, or at least that is what the sign says coming up the drive - Tree Farm.
And, had anyone lived here prior to 1950 or even later, there would have been no commercial power. One of my neighbors still has his wind generator spinning in front of his house - I need make him an offer on that one.

The Rural Electrification Act of 1936 provided loans to extend the electric grid out to farms and rural communities. Like broadband internet connections today, there had been little interest in spending on infrastructure where few customers existed. Earlier, "farm radios" had to run on wind generators or batteries.  

Above: A Philco battery "jar" which would yield 6 volts DC when filled with acid and lead plates - until it was knocked over by the dog.

Above: A Parmak brand "DeLuxe" Model 525 manufactured by the Parker McCroy Co., which is the same company that built the fence chargers we use to keep varmits out of the garden. So they are still in business, still selling farm equipment.

You can usually tell a farm radio from the lack of a visible power transformer and the metal can that houses the noisy vibrator  power supply.  Noisy meaning - It  hums, or buzzes and it can generate some RF hash especially if the little mica cap across the output is bad - and they often are since this is a very rough life for even a mica cap.

All of this makes them less than ideal for collectors that wish to display a working radio. AND it is likely that the power supply no longer functions. Which causes some people to reason "Rather than fix the supply that runs on batteries - that I don't have, let's convert it to  - who knows - something else". These conversions usually result in a radio with missing or damaged parts, which was the case here.

Before I go on, You should know, that this is an uncommon radio. So much so that it does not seem to be correctly identified  on any of the usual internet ID pages. The name seems to be the source of confusion. Now that you know what it is, the schematic can be found in Rider's 13-2. 

To make things more interesting, the schematic shows the source voltage with reversed polarization (positive. ground). DON"T do that! While the syncroness vibrator supply will run with the input voltage reversed the filter caps across the output won't - nor will the radio.

Beside needing caps and resistors, this supply had half of the primary winding open. So it was 3/4 good - or entirely bad, which ever you prefer.

​Being basically lazy, I chose to only fix only the bad winding.

Yep, I used a socket to push the primary winding out of the secondary - this only works part of the time and heat may be required.

Fortunately the open winding was on the outside of the primary ( the outer 1/2 up to the center tap). Had the break been on the inside half, I would have rewound the entire primary.

The magnet wire did not show the typical corrosion or burns from overheating. Instead  the outer windings had become brittle, breaking many times as I unwound the failed 1/2 of the primary.

Now all I had to do was squish it back in there.

Before and After: The chassis got all of it's caps restuffed.

Chassis reassembled.

For a 5-tube battery radio, performance is pretty good on the broadcast band. The cabinet looks OK but it was never all that "DeLuxe".

Coming up: Back On the Farm - Again, a Zenith 5-F-134 in much worse shape.

This is a project rescued from the wood shed.

​I have mentioned the "wood shed" before. It is a small structure used to store wood and parts chassis and occasionally a radio that is so far gone, but interesting enough to avoid becoming firewood - at least for a while.

Received from a fellow collector, this is a Western Air Patrol 5 Tube Super from around 1935. The story on this one was that it had been placed on a table, outside, for a garage sale. Then it rained. Either that or someone had taken it for a swim or used it to decorate an aquarium.

In any case, the front panel was shot. fortunately, the rest of the cabinet was in relatively good shape which is unusual since it is constructed from solid mahogany. Most of the time a "solid wood" panel is going to warp when soaked in water. The entirely missing finish may have actually helped to avoid warping - or I just got lucky.

The knobs were all that was holding the front panel. Most of the veneer was missing. Fortunately, the escutcheon shown missing in the photo above, had been thrown inside.

This is a west coast radio manufactured by the Gilfillan plant in LA. It was built for Western Auto and carries the Western Air Patrol badge, which lights up in the left-side escutcheon. It is similar to radios built by Gilfillan and sold under their name or for retailers such as Herbert Horn (Tiffany Tone). Chassis were very similar as were the cabinets.

The chassis was pretty rusty but the speaker was intact.
Note the tone and band selector knobs on the back of the chassis.

The schematic and instructions on the bottom of the cabinet did not escape water damage.

This radio preforms pretty good - and that is about the only nice thing I have to say about it.

You would think that with so few parts (relatively speaking) that the lay-out and construction would have been easy. But, this radio is one of the worst I have ever seen.

At first I thought that it had been subjected to a lot of marginal repair work. The power transformer was askew, mounted using two bolts since the other two did not line-up. It might be a Los Angeles sourced replacement - the same color (grey) and shape as the originals that I have seen online. The leads did not line up with the original (design) penetration, but , the new hole was punched (flare on bottom side) rather than being drilled as you would normally find in a substitute style repair.

Solder joints were poor. two components leads were entrapped in solder blobs but were still loose. All of the connections to the chassis were poor. In the above picture, see the candohm that is attached by a blob to the chassis and only at one end. This seems to be the case on other examples of this chassis as well. Leads were wrapped but not trimmed.

The clamp on that filter cap was never going to hold it securely in place.

The tone control and the band switch controls exit the rear of the chassis. I would hope that this was due to a last minute production change rather than by design.

The mouse damage did not help. (How hungry does a mouse have to be to eat plastic?)

I broke the cabinet down to its individual panels before reassembling it. This did not take much effort since all of the glue joints had failed and the panels were only held together by  the original tacks and nails. The top was originally cut to shape but the side panels were constructed of several solid mahogany components.

This construction style, where a laminated front panel is affixed to a solid wood box is a characteristic of radios manufactured by Gilfillan at the time. Most cabinet manufactures did not design cabinets where laminated edge of the panel was exposed. Many of these cabinets have exotic veneers and intricate detail - but only on the front panel. There was some pretty wild router work done on the rest of the cabinet(s).

​Other Gilfillan examples below.

Above: A Gilfillan 6T version, discussed here: 
https://www.russoldradios.com/blog/one-of-a-kind

Above: A Gilfillan Allwave Super 6T 6C from around 1934.

Gilfillan was not the only manufacturer to expose the edge of the front panel. In an even worse application GE not only did this but extended the thin vulnerable edge beyond the structure in this M-51 pictured above. I consider this GE design a classic example of  Design By Comity with other questionable aspects beyond the often-broken front panel.

There was enough left of the original front to give me a pattern, I used 1/4" Baltic Birch plywood which is an improvement on the original. After the router, all I needed was veneer. I was able to reuse the two remaining strips where the escutcheons were but the rest had to be replaced. The original veneer pieces weren't really book-matched, more like sequential cuts. So that is what I did too. 

I decided to modify the gloss finish slightly, making it more of a semi, semi-gloss that I then buffed out.

I need to reposition the light bulb on the left to get a little more glow through the Western Air logo.

I derusted the chassis as best I could while preserving as much of the original plating as possible. Removing all of the rust and exposing bare steel would just encourage more rust and I am totally opposed to painting an originally unpainted chassis. One day, maybe I'll locate a nicer chassis. OR(!) if this Corona Virus - stay at home stuff - goes on for too long, maybe I'll get inspired to replate this one.

Works well with just the antenna pig-tail. Impressive with a real antenna.

​Russ

 - - all visits by groups and individuals as well as community support activities at the radio shop/museum have been suspended.

We hope that everyone remains healthy and safe.

If there is an upside to to being somewhat confined to home, I have tunneled into the "wood shed" and extracted a couple of basket-case projects one of which is the  the 1935 Western Air Patrol 5-tube Super pictured above. More later - -

CL ad,       Only a couple of hundred miles away. To the Radio Rescue Vehicle Robbin - er, ah, Sue!

Seems that there are several Scott Phantom versions including the Phantom Deluxe and the FM versions. This is the 18 tube variety without FM.

Probably the first thing people notice about Scott radios is the chrome - or the tubes or the - - -. Anyway, the chrome on this one was a solid 9 out of 10.

If one of these has a lot of rust or, more often, flaking chrome the cost/difficulty of restoration increases exponentially.

SEE:     ​https://www.russoldradios.com/blog/77-chrome-plated-rivets

As Found - In mostly original shape - only what's going on with that Candohm (top)?

I used 2 of the new chassis-mount Ohmite wire-wound resistors for the replacement of the missing voltage divider (brown). Yeah, they are at a little bit of an angle since the new assembly could not use the holes for the original Candohm and I am reluctant to drill any new holes.

I am happy to see a manufacture making resistors of this type. The only drawbacks are the cost and limited resistance values, which is why I had to use 2 wire wound axle resistors in the assembly.

Some of the caps are really hard to get to/service. This transformer is following the 3rd IF tube prior to the 6H6 Detector.

This is the transformer Associated with the RF AVC 6B8G . It is also hard to service and in this case a real pain since one of the windings was open. The only real option is to remove and repair the whole assembly.

I counted the number of windings as I removed the old coil and replaced it with the same number of turns. The old windings were not burnt. See the little green stain on the form (center where the coil was removed)? This corrosion of the copper wire was found in multiple locations while unwinding the failed coil.

Since I could not wind the new coil with the same basket technique as the original I measured the inductance of the original and matched it by removing a couple of turns on my new winding. Important: note the direction of the turns (arrow). As I recall, This coil was less than 60 turns.

Caps restuffed and ready to reinstall.

There were quite a few of the original carbon resistors that were out of spec.  So I made some replacements using modern equivalents (or greater wattage) potted into glass tubing. The hard part is painting the bands which indicate the resistance.

Glass tubing and a  cutter.

I mark out of tolerance resistors with a black dot as I do the initial survey - replacement in hand.

Parts replacement finished, time for alignment.

As I started the alignment I noticed audio levels were lower than I expected. I thought it would improve as I proceeded - it did not.

OK! Everything looked good. All voltages were correct and the alignment results were as expected only with little improvement in audio level AND now that I could drive the output harder (following alignment), there was some serious distortion particularly in the bass response.

You all know Occam's razor - If the speaker sounds bad, maybe it's the speaker. Well, it didn't hurt to check everything else first, but it was the speaker. Not a bad cone or transformer. No, it as much more simple. The voice coil former had been screwed - more precisely, there was a screw lodged between the former and he frame.

The culprit - a wood screw. 

This screw seems to be of about the same vintage as the radio. It had been lodged here for long enough that it had made a wear-mark or dent in the coil form. It makes me wonder if the original owner had ever heard this radio working as it should.

Spending most of a day finding a needle in a haystack, but a big improvement. 

Bramar cabinet with the old finish removed. As with the chrome chassis, the cabinet was in really good shape, but, as with most things stored in a garage for years, the finish was poor.

Sealer applied.

Toner added and the first topcoat. There are many versions of this cabinet as well as at least two finishes. One type has more toner for a darker finish. This is the lighter variety.

A darker version can be seen here:    ​https://www.russoldradios.com/blog/77-chrome-plated-rivets

New grill cloth which is the old Grill Cloth HQ pattern (no longer available) and a new dial cover/lens which I fabricated on site.

Almost makes you want to place the front side against the wall.

..

 - - -Better living with chemistry from  Chef Russ.

The red goo was starting to get lumpy. Not much shelf life and too expensive to waste,  I needed to get this project finished before the cost went up.

​The  high-temp silicone molding material is always fun to work with, it seems to spread like some demonic force. No matter how careful I am it ends up on my tools and bench. It reminds me of the "Red Matter"from the Star Trek movie in which a very small amount was used to blow up a whole planet (Vulcan). Guess I better not drop any - ahh! Too late - - 

​Above: Original grill on rt. On left is a temp cover to prevent finger-damage to the speaker cone.

Going with what I have seen on my two radios, it appears that these models are often missing the speaker grills for the midrange speakers mounted on the sides. Of the 4 needed, mine only had one. Fortunately that one was in good shape and could be used to make a mold. 

The wooden box is used to form the red silicon mold. Some trimming  of the new mold may be required. Don't forget to  use a mold release agent. The side of the mold that you see was face down in the box/form.

Above is a grill-in-the-making. In this case I used resin. The advantages of using resin is that it is readily available at hardware stores and that it can be tinted (tints are not at hardware stores. Sometimes "plasticizers" are available but they are intended to make "gel-coat" and not what I use.)

The mix-ratio is variable depending on temperature and your desired set-time.

The biggest draw-back is the difficulty in removing bubbles from the viscous mix. The shorter the cure time, the harder this becomes. One advantage of using the high-temp silicone mold is the ability to warm the resin in the mold. This will shorten curing time tremendously and help to eliminate the sticky surface that often occurs when molding resin. It will also reduce the time you have to work out bubbles. I used heat from the wood stove to harden these after they had begun to set up. The silicone mold will tolerate about 600 deg F, The resin WILL NOT(!) I would not exceed 100 Deg, by much.

​I have had trouble with resin parts remaining soft for long periods. Using the correct mix and temperature will reduce this issue. Use the least amount of tint possible to achieve the desired color.

Above:  A resin grill in place. It is OK and looks good from a few feet away but it is rougher than I would have hoped (most people would not notice),

So I decided to  make a few more using 2-part polyurethane "Model Pro".

These came out of the same mold much cleaner with crisper detail and very few bubbles. But, as you can see in the "chemicals" picture below, the 2-parts, one clear and the other a greenish-brown, become bright white when cured. This stuff sets in 2.5 minutes and gets quite hot doing so. You have to work fast but the relatively thin mix allows bubbles to escape MUCH more easily. Using the high temp silicone is no worry for the heat produced. I would NEVER heat this stuff to cure and be aware that it can get VERY HOT all by itself.

A good mold release agent is recommended by the manufacturer. It will keep the new part from sticking to your mold. It may also cause paint to fish-eye and other adhesion problems.

Hint: Paint the white plastic grill with black lacquer first. Then follow with your custom-tinted, brown top coat.

Another issue with having to paint the grills is that "mold release agent" that I keep mentioning. It can really mess up your paint. The new part can have the characteristics of silicone contamination. I found that the hardened part is stable when exposed to lacquer thinner for a SHORT time. I used a shallow metal pan to wash the part. Thin areas of flashing will also become soft quickly so they can be brushed off rather than having to cut them off. The thinner can remove MOST of the release agent but be prepared for issues. Apply the black primer coat first and try to spray your paint on as dry as possible. I have not tried non-lacquer based paints.

P.S. I almost forgot to add, the black lacquer that I used was just out of a spray-can but the brown was applied with my sprayer, so I had the luxury of being able to add fish-eye reducer/flow-out to the mix. This was a big help in reducing these issues.

Above:  Painted poly grill

Poly and resin grills side-by-side. The colors are a match since I used the same tints in the resin that I  used to tint the lacquer paint.

Made in the same mold:  Left Polyurethane    Right Resin 

​The painted poly grill has a better finish than the resin grill.

New Grill installed in the Saba 400. These were a friction-fit with maybe a little glue around the edge. It is possible that those that were missing simply fell out of the hole  in contrast to the brittle/distorted plastic failures seen on earlier parts. Evidence for this is the  good condition of the single remaining original grill used in the mold.

Some, but not all, of the chemicals used.

​Wear your protection - -

This is obviously not a kitchen project. If you want to give this a try make sure that you have a well ventilated and suitable place for the project. Wear protective gloves and clothing . Read and follow label instructions - and don't yell at me if you get red goo all over the place.

I would estimate the cost of the pictured chemicals at about $200.

Label on the shore 60 silicone "Limited Shelf Life". I would not count on this stuff remaining viable for more than a year. Unlike many two-part solutions, close is really not good enough for mixing in the hardener. A person really needs a scientific scale to get the 100 to 3 mix ratio correct.

With many of these projects, I am asked  if I will be selling these parts. No. I have too many other projects. Of course, if you would like to install the hydraulics on the tractor for the new backhoe, I'll make you a pair of grills. Otherwise, that is what I will be doing for the next few days ;-)

The CL post was old. It was not local. Diamond Oregon - where is Diamond Oregon? No wonder the two rare German radios had not sold, Diamond is in the shadow of Stein's Mt., near the Malheur Bird Sanctuary made famous a couple of years ago by the "occupation"  - - - out in the Great Basin, basically a swamp in the desert of Eastern Oregon.

So we jumped in the Radio Rescue Vehicle and headed East. We got to Burns and turned South. Stein's could be seen in the distance. The valley is lush surrounded by dry, desert hills. It is a paradise for birds - and mosquitoes.

We stopped along side of the deserted road. Boy! There are sure a lot of gnats (needing my reading glasses). Thousands of  - hey wait a minute - mosquitoes! We could not get back in the truck fast enough, followed by the swarm. CLOSE THE DOOR! Maybe that is why the radios were still there. All of the potential buyers had been eaten.

I guess that I was occupied swatting since I forgot to take any pictures of Diamond. Maybe I just did not want to remember. I am sure that it is a nice place, sometimes, but you could not pay me enough to live there.

Did I say that there were 2 radios? I meant three, two that I wanted and - a console.

The Saba Freiburg Automatic 3DS is pictured above sitting on a Arabella console which I was talked into taking for $50. There just wasn't much time to negotiate. By this time I was feeling about a quart low. Nothing a gallon of cortisone couldn't fix - I hoped.

We found the 12-tube 3DS sitting on top of a Saba 410 Automatic made for the US market in 1963, stacked like cord-wood in the corner of a bedroom. We discovered that the placement was more strategic than chance when we lifted the 3DS off of the 410. But the price was right ($250 each, about 1/2 the asking price). 

Prior to this year I had never run into a radio that had a thick, factory , polyurethane finish and at the time I thought it had been refinished, but no, it just needed to be refinished.

The poly was so thick that it cracked lengthwise at least 3 times. So thick that it had pulled the veneer up along the cracks. Ouch! Another good reason to hate poly.

But, hey, the radio still had the sales tag on it, right in front of a woofer where it would bob about like in the wind, but more on that later.

​We were out of there.

Fearing the worst about refinishing the 410, I started on the 3DS Automatic. 

None of the radios worked - "They did work" when the sellers family brought them home from Germany. They weren't in the US military, so I am not sure how they would have acquired the US model 410 IN Germany. Maybe a person could just buy the export model. From experience I knew that finding export models of famous US manufactures in the US is rare. Finding either of these radios anywhere today is also rare and potentially costly. I was happy with the radios - and - so far showed no signs of having contacted malaria, or EEE, or ebola - - - scratch that.

Remove the chassis from the cabinet without damaging any of the Saba "green cone" speakers or breaking a dial string, of which there are several.

​The good news was that this cabinet only needed a little glue, here and there, and some touch-up on a few scratches.

After a few years a person becomes familiar with US made parts, enough that testing certain components is a waste of time - "THAT type of cap is always bad" -  not many US parts here. There really aren't a wide variety of parts used in this chassis, just a lot of them. Still, much of the same applies. For instance, ALL of the caps with the dark blue labels are BAD After testing a few I knew that they all had to go. Good thing, they are easy to re-stuff. I do not recall having to replace any resistors on this one . Not so, the 410. I suspected the little red/polystyrene caps, having seen a few bad ones before, but, these were OK too.

These "paper" caps had glass tubes, just like some of the replacements that I build, so restuffing (rebuilding) them was easy. They were sealed with tar.

This radio had what appeared to be, original, European produced tubes, some of which had become weak. A few of these have direct, US made replacements. Some have US replacements that are similar. I replaced the weak tubes with exact replacement types by the appropriate manufacture. For example, a Telefunken ECC83 would be replaced with a Telefunken ECC83 rather than a US 12AX7, which would work just as well. I like to keep unusual radios as original as possible while still being reliable.

It also needed a handful of the hard to find European panel lamps. Little grain-of-wheat lamps can be installed or even fitted into screw bases but lately I found some direct replacements. Cleaning of contacts, of which there are MANY, and lubrication can take a few hrs. Did I mention - DO NOT Break a dial string (!)? Yeah, I learned that on the 400 I worked on earlier:

​https://www.russoldradios.com/blog/40-old-radios

All of the electrolytic filters were restuffed with 450V Nicheon caps. There are some motor-run caps in all of these motor driven, automatic models. I only replaced the ones on the 400 (link above) since the originals tested OK and finding the correct AC cap in my parts stash was unlikely. ESR seemed to be low (OK) so, if one of the tuning motors began to run slow I would replace them later with correct AC types.

Really, there wasn't anything challenging about the chassis restoration. Now for the alignment which can be very challenging.

First, take a look at the test cables I built, above. You might be able to get by with a bunch of clip-leads - no, you are going to blow everything up, better build the cables. One cable (not shown) is just a speaker cable extension. You really need the speakers for alignment  and you don't want to remove them from the cabinet if it can be avoided. The top cable gives you all of the test points that you will need for alignment, As you can see it is terminated into a  7-pin miniature tube socket, so you need to find a 7-pin male connector. The lower cable allows remote connection to the multiplex adapter port. This is very helpful for working on the adapter. The connections are speced out in the manual. If you do not have the manual  I would strongly advise you to not attempt alignment. This cable will work with the 410 as well. (Interesting note that I had been told that the test port on the 400 was for a multiplex adapter like on the 410 - it isn't.) The test/alignment cable will also work with the 400US. Alignment documents can be a little hard to find. Saba did not encourage field alignment, at least on the earlier models. 

When aligned properly, there radios have a search/AFC function that is partially mechanical. A motor constantly makes frequency adjustments and the action is visible in movements of the tuning knobs. When people visit, I like to turn on the radios and ask them to retune to a different station. Unless a person gets a firm grip on the knob the radio will resist and retune to the original station. If the control is moved enough to loose the original station, it will automatically move on to the next station in the direction that the manual adjustment was made - or you could just push one of the search buttons.

​Though few of these radios still have the remote, or they never had one, they had the capability to use a wired remote which included tuning, volume and other functions, depending on model. I have only seen pictures of the remote.

Above is a shot of the tweeter configuration on the single channel (mono) 3DS. Why they did not maintain this configuration into the stereo units like the 400 and 410 is not clear to me.

Above is the stationized dial and the tuning eye which is an EM34 that has 2 "shadow angles" one on top and one below. The indicators close sequentially as the signal strength increases. In this picture both indicators are closed on a strong station.

Above is a demo of the 2-segment eye tube used on the 3DS.

This video should give you some idea of how he automatic tuning works. Watch the tuning knob on the right

I needed to start the cabinet restoration on the 410 Continental as I was restoring the chassis knowing that removal of the poly finish was going to be a really ,slow, pain. This is the second  poly finish on a German radio that I have had to deal with this summer. The first was a Grundig stereo with matching speakers. It suffered the same fate as the 410, long splits in the poly finish that also damaged the underlying veneer.

When finished I gave the Grundig to a friend. It was a good prep for striping the Saba. I have dealt with thin poly finishes before by applying many coats of stripper slowly removing the finish. The poly is very resistant to chemical strippers and the veneer would not stand up to much physical abrasion especially with the existing damage. So, you can sand the cabinet when it is removed but sanding the poly off was out of the question.

I ALWAYS strip cabinets outdoors. In this case, that is even more important. I usually apply stripper in the cool mornings to reduce evaporation which allows the stripper to remain active longer. This job was going to take days and that turned out to be enlightening.

I started in the morning and after 2 or more applications, not much progress was made. The sun was approaching noon and the temperature was rising . I was both annoyed and impatient so I applied the stripper again. It began to bubble and steam quite vigorously. I though that this was going to be a waste of stripper - - but the poly began to peal up! What resulted was large pieces of the foam-like substance I am holding above. It still took a day and most of a gallon of stripper but I managed to get the poly off.

A note:
Good strippers are hazardous in many ways. "Green" strippers are usually too weak to remove poly finishes - or any finishes - and if they do work the resulting material is no longer "green" since it includes the old finish, not to mention the fact that you generally have to use much more of the ineffective stripper to accomplish anything. Most of the MEK strippers have been removed from the shelves at the big box stores. This is likely an attempt to avoid litigation from injuries caused by improper use - or - possibly, proper use. If they are worried about it, you should be too. If a job can't be done avoiding contact with the material and fumes - DON"T DO IT.

So, do you think that I used poly on the cabinet restoration? Hell no! I used lacquer. If there is ever the desire to return to poly it can be applied over the well cured lacquer in a thin application and the lacquer is likely to save the veneer from a repeated poly failure.

A couple of notes on the cabinet:

This cabinet is very much like the one on the earlier 400. The only significant difference, besides the finish, is the use of white-wood strips used to high-lite the leading edge (front) where as the 400 used brass (colored) metal trim. The wood is easier to fix but I think the metal looks better.

Saba named series of radios after German cities. The top of the line was named Freiburg. This must have been an annoyance to the lesser named towns, or maybe not. Anyway this US import model was called THE 410US Continental but the cabinet is stamped Frieburg which makes sense because it is very similar to the domestic (German) Freiburg models . This US model is similar to the Continental 410USE for the European market.

See what I mean about the speakers. The 410 has 5 speakers with the mids (side) clearly being superior to the 3DS but they used a single forward facing tweeter which, to me, would seem to conflict with the newer stereo design. But you really cant take advantage of stereo with rhe speakers so close together anyway. But what do I know, It still sounds great.

​Hey, I have a cure for that speaker separation issue - later.

Chassis look familiar? I guess that they had a good thing going, all they had to do was make it stereo. The output went from  two EL84s running in PP to ELL80s, one per channel (stereo). FM was mono unless the 5 transistor multiplex adapter is plugged into the factory socket. 

I found an owners manual for the US model which was in English. It had service information/alignment that was translated from German. This is good BUT the translation is literal. It can take a while to understand the meanings, for example: "Tune L283 subcritical" which means detune L283 from it's peak. Inversely "Tune L283 critical" means, peak the output. This can take a little interpolation but it was a lot easier than trying to read German.

That 330K,  1/4w  carbon resistor (orange orange Yellow silver) had become intermittent, mostly working when I was looking at it and going open the minute I turned the chassis over.  The lead wire had become loose as can sometimes happen with this type of resistor. When it was open there was no audio on FM (it is in the IF string).

Saba Villingen 400 Automatic Stereo (13 tubes)(left) and the Saba Freiburg Automatic 3DS  (12 tubes, 18 watts of audio)

The best way to get good stereo separation? - - - use two receivers. Running each receiver in mono mode gives you twice the power/overhead somewhere around 18W per channel. This may look a little odd but the results are awesome.

​I still need to try to cast some replacement side-speaker grills. These seem to be easily broken and I need 3 of them.

I would like to thank Thorsten Michael Ritzka for his help with finding schematics

It has been a very busy summer - sorry. Watch for a posting on the $65 Scott Phantom restoration, soon.

I have really never liked this cabinet design. It could have been more appealing if the colors/veneers were different - and the shape was less of a tombstone, cathedral compromise. But they did not ask me. I can see where they were going, kind of a "what's next" following a very attractive and successful cathedral marketing campaign. And, yes, I really like the 16 cabinet.

There is reason to believe that others shared my view of the cabinet since a mid-production change resulted in a more conventional (yet bland) tombstone cabinet design using the same chassis with minor updates. However, the 10" speaker was reduced to a 8" version.

Well, cabinet aside, the 116B is an impressive radio for the time, which was more or less, 1936.

As-Found on local CL for $35

This is an 11-tube radio with an RF amp and 2 IF amps, all of which are 78s. I would compare it very favorably with any 12 tuber since the 12th tube in many designs was an eye-tube (signal indicator) which in the Philco is replaced with a Shadow-Graph which is superior in the sense that all eye tubes suffer from short life - possibly a year in regular use. Where as the electro-magnetic shadow-graph is still good 83 years later. A shadow graph is basically a standard meter movement where the pointer is replaced with a "vein" that covers and uncovers a bulb as signal increases.

The cabinet and chassis were in great shape. Unfortunately the very dark colored cabinet section shows every abrasion and mark even in dim light.

There were only a few replacement parts. Note the yellow cap in the lower right - a typical replacement for the short-lived "wet" electrolytic filters. One of the original can-caps was still present. I found an exact replacement for the missing can in the parts-stash and began the process of rebuilding or "stuffing".

Note that the replacement cap is a 630V 10uf film cap. (metalized Polypropylene) not an electrolytic with an expected durability/lifetime benefit.

Yes, the + stud/lead is a piece of Romex (TM) with its own insulation which assists in insulating the B+ if the original rubber insulator is degraded or missing.

Filters done, time to do the rest of the caps and make replacements (molded) for about half of the original resistors. This process is discussed in earlier posts. Additionally, all rubber mounting components are replaced.

Chassis ready to go, now on to the cabinet.

Above: I have had to adjust the brightness of this exposure to assist in illustrating the process. The really dark cabinet is difficult to display accurately in a photo and is greatly affected by the intensity/brightness/direction of the illumination.

Have you ever noticed that, following the removal (stripping) of the original finish, there is still an artificial tone to the wood? I believe. with pretty good certainty, that many manufactures used both toner and dye to tint their cabinets.

Chemical stripper usually leaves the tint created by dying the wood behind, but sanding can remove most, or all, of it. Above, the cabinet has been stripped and several coats of dark walnut dye have been applied to the trim and arch.

Don't confuse "dye" with stain. They are not the same.

As I said, taking a picture of a surface that is this dark with enough light to show the tint is tough. In the pictures above, the picture on the left is as-found and the picture on the right is after dye, toner and a top coat. Pay attention to the areas in direct sunlight and you (might) see that the finish as  a VERY dark reddish-brown (very dark walnut).

You might also ask - why did he refinish that radio? Well, the problem with the photos also hides the issues with the dark cabinet. When I first looked at the radio in a moderately well lit room I thought that I would not have to refinish. But once the radio was well lit the stains (top) scuffs and scrapes were painfully clear.

My first instinct was to tone the dark areas with Dark Vandyke Brown. I often use this toner on trim that  appears black. VD Brown is a great color - when used in moderation or on small surfaces. But when applied heavily on large surfaces it takes on a greenish cast that I find disagreeable. (keep in mind that applying SO MUCH of any toner that any and all "highlights" are covered up is generally wrong - or at least inconsistent with the way it was originally done). If the original toner did have the greenish cast it may have been moderated by the yellowing of the top coat, but, I think that the tint(s) used in the 1930s were slightly different than those available today.

So, what I did was  mix up some lacquer with the Extra Dark Walnut dye as a tint.  I also modified the lacquer topcoat so that it is closer to semi-gloss than full gloss, but(!) after a week it was buffed out. The large dark area also was the cause for modifying the gloss.

I would have to see many more examples of original finishes to modify my color scheme but for now, this is my conclusion.

Like I have said - I need a BIGGER bench!

Following alignment I found this radio to be very capable. The only issue I have with it is minor. When aligned as per the instructions I find that the top end of the broadcast band is SO hot that a long antenna just swamps the receiver. Actually it receives all of the local station with no antenna at all. My first instinct was to detune the IF slightly but this would affect short wave performance too. So I decided that a moderately sized antenna was a better solution, switching to a longer one for DXing on SW. Another thing that occurred to me was to peak the broadcast band near the center rather than the top as is generally done. As-is the over-driven phenomena is limited to 1.2mhz and above. There are two tie-ins to this , one being the shadow meter which is very responsive on the upper BC band and X-band and less so elsewhere and the X-band is also very hot, though listening there is limited mostly to beacons and such - nice beat, but vey repetitive. One other note in this respect is the option to add Philco's loop antenna to the connections provided for it. I would assume that this would reduce the issues found with a long wire. I don't know how well it would work for short wave.

In conclusion, this is a very capable radio comparing well with other 11 and 12 tube radios of the time - I guess that I'll get used to the cabinet design - maybe.


P.S. Get someone younger to lift it onto the bench.

Harry sent me some tubes.

I try to keep the correct original-type tubes in the radios that are on display. So I had been talking about finding the Arcturus made "Crosley" branded, BLUE tubes for my 1931-1932 Crosleys like the Buddy Boy. Most of these tubes have become harder to find than the radios.

Several causes for replacing the original tubes are likely. First - "OH LOOK AT THAT COOL BLUE TUBE" which has a corollary, "I'LL SELL THE BLUE TUBE FOR $$ AND REPLACE IT WITH A CEAR GLASS TYPE" Second, in my opinion, Arcturas tubes were less than average in reliability. The company was very innovative but this did not translate into longevity both in the tubes and the company. So the original "blue" tubes often had to be replaced.

At this point I should explain what a Arcturus "BLUE"  tube is, but this site has already done a good job:

http://www.bill01a.com/articles/arcturus-a.htm

Having invented one of the first power pentodes is still not as important as the blue glass, at least in collector appeal.

Here are 2 "PZ" tubes made by Arcturas and co-branded for Crosley. The PZ was developed prior to the RCA 47  (247) but was similar enough to be used in the same circuits. At some point Arcturas had difficulty sourcing the blue glass, even prior to the conversion to ST shaped bulbs. Pictured on the right is another PZ I already had with a clear G bulb.

And, here is the box in which the blue tube was residing. Do you see any issues?

Well, while being related to a 42 the PZ is clearly NOT. Besides the base configuration (it wont plug in). a PZ is a relative of the 47 which has a 2.5V filament compared to the 6.3V filament of the 42. No wonder it tested SOOO good.

At some time someone must have tested it as a 42 on a TV-7 since it was marked 90(?)/50, a very high reading and indicative of TV-7 test values. No wonder, it was lucky to have survived the test! I know that this was prior to Harry since he does not have a TV-7. Is seems that nobody even noticed the difference, or the 5-pin base (a 42 has a 6-pin base). The tube required a rejuvenation since the high filament voltage had "paralyzed" the cathode. This brought it up to near new spec.

True, the PZ in the box might have not been the original tube in the box. But even if it had been a "42" we still have a problem here. And true that today just about anybody can print and paste labels, but this tag is very "vintage" and appears in text and color similar to other Arcturus printed material. Note that one of the end-flap tags has also been changed to "42". It does not appear that the other "PZ" label had ever been covered.

So, no - not true.