I own a July 29, 1929 RCA Radiola 46, model AR 596. It needs two things to start: there are three tubes missing and with the schematic I have..it is difficult to tell exactly which numbers they are - it is either three UY224's or two UX222's and one UX 112-A. The radio does have two other tubes, a UX 245 and a UX 280, but I can clearly see these on the schematic and they are still in the radio and labelled on the chassis. (why the others couldnt be is a torture.

The second Item - there are two wires attached to the right side of the chassis that go nowhere..seemingly related to the third tube coil on the right side of the chassis. There is a switch on that side of the cabinet that has no wires going to it that is marked 'local' and 'distant'. The wires may go there, but I can't tell from the schematic I have downloaded from this site. Also, I don't want to 'try' to put these on the switch w/o knowing if they should go there as they may blow other
components.

The cabinet is in pretty good original shape and i'd like to hear it play. So, what the radiola needs is: what are the three other tubes besides the UX245 and UX 280 and where sre those wires supposed to be connected?

Thanks, Steve

The reason why the chassis is confusing is because this radio was made as both a strictly AC radio and a strictly DC radio. The DC radio employed all filamentary tubes--#222 (3) in the RF section, a 112 and (2) 171 tubes in the output section. Notice the lack of a rectifier (#80) and power transformer in this radio. No rectifier was needed for this radio because it was operated from 110 volts DC (remember...some cities used DC back then). Push-pull operation was also probably used because the maximum available voltage was 110 volts. Push-pull audio yields more audio power.

Your radio is the AC version, since it does have a #80 rectifier tube. You should also see a power transformer. A single #45 tube is used in the output, as this is all that is needed to obtain adequate audio power with the high voltage power system used in this radio. In the RF section, (3) #24 tubes are used. These tubes employ indirectly heated cathodes, which is usually necessary in RF circuits of AC radios.

As for your two wires in question, it is best to state what they connect to. This will allow others to determine their function for you. If one connects to the end of the antenna coil and the other connects to a .00025 MFD condenser that connects to what looks like the chassis in the circuit diagram (should at least go to the ground terminal on your radio), then these are indeed the wires for the local/distant switch.

Once you obtain all of the appropriate tubes for your radio, don't fire it up just yet. Be sure to test ALL condensers for any trace of leakage. Electrolytics, if any (I didn't check), should have no more than 10 meg leakage (none is optimum), and when any value above 1 MFD is tested on your meter, a good electrolytic will cause the meter to swing ALL THE WAY to zero and then fall slowly back down to 10 meg or higher. Weak ones will not cause as much of a deflection. For now keep reading, but later on, after you have gotten your set to run, you should check the electrolytics again after perhaps an hour of operation. At this point they should have rejuvenated and should have no leakage. If they still have 10 meg leakage or there-abouts, they are questionable, and replacements would not be a bad idea.

All other condensers should have NO LEAKAGE. Any value above .001 MFD will cause a very small deflection of the needle (barely noticeable in many cases). Any value below .001 MFD will not likely cause a noticeable deflection. Should the needle be deflected in any case, it must fall back to EXACTLY where it started. Any leakage, even in the millions of ohms, will cause the set to perform at less than optimum. Check condensers by disconnecting them from the circuit. Check your resistors for proper values, too, and disconnect them as well during the test. Do not touch both meter leads with your hands or you will throw off readings.

Good luck!

Thomas

Also, to fire up the set for the first time, you should build an arrangement that will allow you to operate the set in series with a light bulb. Mounting a light socket and an outlet to a board and then wiring the two in series and to a cord and plug will do the trick. Start with a 60 watt bulb or so and slowly work your way up to about 150 watts, maybe 100. Observe the set as you do this and observe the bulb as well. A 100 watt bulb or more should not burn at full brightness. It should be dim. See if you can operate the radio from a 100 watt bulb. If not, go for a 150 watt bulb. When operating the set for the first hour, use this arrangement. It will somewhat buffer the power supply of the radio, should anything go wrong in the radio. Electrolytics are the big risk. Ideally you should replace your electrolytics, but some people like to keep the originals if they work. Often you can open up the originals in an inconspicuous place and stash new ones inside. As I said before, there are tests that will pass or fail an electrolytic, but on rare occasion, even if one passes the test, it can fail when it gets to be this old.

Thomas

Thank you SOOO much, Thomas- for your time..I will let you know what happens and other questions I may have :Also, to fire up the set for the first time, you should build an arrangement that will allow you to operate the set in series with a light bulb. Mounting a light socket and an outlet to a board and then wiring the two in series and to a cord and plug will do the trick. Start with a 60 watt bulb or so and slowly work your way up to about 150 watts, maybe 100. Observe the set as you do this and observe the bulb as well. A 100 watt bulb or more should not burn at full brightness. It should be dim. See if you can operate the radio from a 100 watt bulb. If not, go for a 150 watt bulb. When operating the set for the first hour, use this arrangement. It will somewhat buffer the power supply of the radio, should anything go wrong in the radio. Electrolytics are the big risk. Ideally you should replace your electrolytics, but some people like to keep the originals if they work. Often you can open up the originals in an inconspicuous place and stash new ones inside. As I said before, there are tests that will pass or fail an electrolytic, but on rare occasion, even if one passes the test, it can fail when it gets to be this old.
:
:Thomas

Thomas - I am going to look at the wires more closely, I think they are attached where you suggested they might be. Do you have a place to acquire tubes that you'd recommend? Thank you, Steve :Also, to fire up the set for the first time, you should build an arrangement that will allow you to operate the set in series with a light bulb. Mounting a light socket and an outlet to a board and then wiring the two in series and to a cord and plug will do the trick. Start with a 60 watt bulb or so and slowly work your way up to about 150 watts, maybe 100. Observe the set as you do this and observe the bulb as well. A 100 watt bulb or more should not burn at full brightness. It should be dim. See if you can operate the radio from a 100 watt bulb. If not, go for a 150 watt bulb. When operating the set for the first hour, use this arrangement. It will somewhat buffer the power supply of the radio, should anything go wrong in the radio. Electrolytics are the big risk. Ideally you should replace your electrolytics, but some people like to keep the originals if they work. Often you can open up the originals in an inconspicuous place and stash new ones inside. As I said before, there are tests that will pass or fail an electrolytic, but on rare occasion, even if one passes the test, it can fail when it gets to be this old.
:
:Thomas

There are tons of great places to acquire tubes. The two that I go to the most are www.tubesandmore.com (a supplier of just about everything you'll need for your radio including new cloth wire), and eBay. You can find all of the tubes for your radio on eBay. www.tubesandmore.com doesn't always allow you to select brands, though RCA is the most popular, so your chances of getting RCA tubes is high. On eBay you can see what tubes you are getting (usually), though in your case they are usually used. Try to go for tubes that are tested. www.tubesandmore.com sells both new and used tubes as well, and their catologue is easier to read than their web site (it isn't like going through a maze and hitting dead ends all the time...you just page through and look at all that you want). Their web site has more updates, though.

Thomas

thanks again, Thomas

:There are tons of great places to acquire tubes. The two that I go to the most are www.tubesandmore.com (a supplier of just about everything you'll need for your radio including new cloth wire), and eBay. You can find all of the tubes for your radio on eBay. www.tubesandmore.com doesn't always allow you to select brands, though RCA is the most popular, so your chances of getting RCA tubes is high. On eBay you can see what tubes you are getting (usually), though in your case they are usually used. Try to go for tubes that are tested. www.tubesandmore.com sells both new and used tubes as well, and their catologue is easier to read than their web site (it isn't like going through a maze and hitting dead ends all the time...you just page through and look at all that you want). Their web site has more updates, though.
:
:Thomas

Thank to you Thomas, I can get the tubes! Now the wires going to the 'distant'/'local' switch are the only hitch. The switch has three connections - only two wires, so, does the ground wire or the power wire to the coil (which are the locations as as you guessed) split to cover two of these connections or can one of the connections be open? All three have spots of solder on them and look as if they've been hooked up - BUT - which wires?..the schematic does not show this at all. Thanks again -~ Steve

:There are tons of great places to acquire tubes. The two that I go to the most are www.tubesandmore.com (a supplier of just about everything you'll need for your radio including new cloth wire), and eBay. You can find all of the tubes for your radio on eBay. www.tubesandmore.com doesn't always allow you to select brands, though RCA is the most popular, so your chances of getting RCA tubes is high. On eBay you can see what tubes you are getting (usually), though in your case they are usually used. Try to go for tubes that are tested. www.tubesandmore.com sells both new and used tubes as well, and their catologue is easier to read than their web site (it isn't like going through a maze and hitting dead ends all the time...you just page through and look at all that you want). Their web site has more updates, though.
:
:Thomas

Well, if you know that the wires you see are indeed the local/distant wires, then you may connect these to the switch in any way you see fit. I will have to think about why all three terminals were used. The switch may have simply been a two position switch at hand at the factory, which was also used for other purposes. The ideal way to wire the switch would be to find out which terminals are closed when the switch is thrown to the local positon. The center terminal is likely connected to the moving contact. Connect the ground wire to this terminal and to the terminal that is OPEN. Then connect the antenna coil wire to the terminal that is closed, or connected to the center terminal. Connecting the ground wire to the open terminal has no real purpose other than to perhaps provide a little bit of shielding. It is not necessary as far as I can see. Sometimes manufacturers made connections like this, though, which may or may not have improved set performance.

To go into a little detail, another example of a connection not needed is where a manufacturer wires a variable tone control. One end of the potentiometer is connected to a condenser that goes to the audio circuit. The center wiper terminal is connected to ground. The other end terminal is also connected to ground. There is no real purpose for this. When the tone control is turned to maximum resistance, the wiper will be touching the high end of the resistance element and the external connection will also connect to this end of the element. Redundant, but done just the same.

If I come up with any other theories on the switch wiring, I'll let you know. Perhaps someone else will come up with an idea, too, but as far as I can see, the switch should be wired as I stated above.

Thomas

Thomas..I really appreciate the time you take and the knowledge you share..I will get right on this and if you have any other theories..I'd like to hear those too. I will let you know what I find.

Perhaps I can do something for you in the future!

Steve

:Well, if you know that the wires you see are indeed the local/distant wires, then you may connect these to the switch in any way you see fit. I will have to think about why all three terminals were used. The switch may have simply been a two position switch at hand at the factory, which was also used for other purposes. The ideal way to wire the switch would be to find out which terminals are closed when the switch is thrown to the local positon. The center terminal is likely connected to the moving contact. Connect the ground wire to this terminal and to the terminal that is OPEN. Then connect the antenna coil wire to the terminal that is closed, or connected to the center terminal. Connecting the ground wire to the open terminal has no real purpose other than to perhaps provide a little bit of shielding. It is not necessary as far as I can see. Sometimes manufacturers made connections like this, though, which may or may not have improved set performance.
:
:To go into a little detail, another example of a connection not needed is where a manufacturer wires a variable tone control. One end of the potentiometer is connected to a condenser that goes to the audio circuit. The center wiper terminal is connected to ground. The other end terminal is also connected to ground. There is no real purpose for this. When the tone control is turned to maximum resistance, the wiper will be touching the high end of the resistance element and the external connection will also connect to this end of the element. Redundant, but done just the same.
:
:If I come up with any other theories on the switch wiring, I'll let you know. Perhaps someone else will come up with an idea, too, but as far as I can see, the switch should be wired as I stated above.
:
:Thomas

Nope. I just give advice. I don't take anthing in return.

Thank you, Thomas..I orderd the three tubes I needed this morning and just have to figure out the wiring to the switch (hopefully) .

The question today is: I was looking at the other two tubes and saw the UX 245 there is actually labelled UX 345 (Cunningham brand). Is this okay? Or will it not function or cause damage?

Again, Steve

:Nope. I just give advice. I don't take anthing in return.

The reason for the 3 instead of the 2 is because numbers were not as standardized back then. The two digits at the end are the tube number and the number before them has to do with the manufacturer. In the field they are simply referred to as #45 tubes, same as the #80, 01A, 24, 27, 47, etc.

More modern tube numbers dump the whole manufacturer concept and simply label the number itself, such as 2A3, 6A7, 6D6. Then with octals, you'll find shell designation like no designation for metal, G for large glass, and GT for tubular glass. Etc.....

Thomas

The 345 will wok just fine. Initially that first digit denoted the manufacturer. The two digit types are funtionally the same tubes for future reference- the 245/345= 45, etc. The only exception are some specialty tubes and Western Electric (whose numbering system is strictly their own)

:Thank you, Thomas..I orderd the three tubes I needed this morning and just have to figure out the wiring to the switch (hopefully) .
:
:The question today is: I was looking at the other two tubes and saw the UX 245 there is actually labelled UX 345 (Cunningham brand). Is this okay? Or will it not function or cause damage?
:
:Again, Steve
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::Nope. I just give advice. I don't take anthing in return.

Steve,

I'm bringing back to life a Radiola 46 at this time. Your tube questions were already answered. For the local/distant wires, looking towards the back of the switch, yellow-right black-left on the bottom, and green for the single top terminal. There's another apparently yellow wire soldered to the bottom of the raceway that the other wires run in, if your raceway is still there.

Regarding the filter caps, they are all wax paper, located in the box diagnal from the 80 and 45 tubes. The output choke is also in this box. Something of a PITA to replace and restuff with all the wires, but doable, and I'd suggest you do.

Also look for problems in the power resistor banks. There are two banks of big ceramic resistors. Out of nine total sections, 8 of mine were burned open. Rather than try to cram in all the new ceramics, I ran leads out of the chassis to a seperate board. I'll mount that board vertically when I put it all back together for air flow.

I've got service information if you need it, or you can get your own here:

http://www.radiolaguy.com/manuals.htm

Good luck!
Richard
RichardD "at" fool.com

:So, what the radiola needs is: what are the three other tubes besides the UX245 and UX 280 and where sre those wires supposed to be connected?
:
:Thanks, Steve