hi i am trying to get a coronado mod. 962 going the electrolytics were missing it has a 10 uf and a 16 uf i have hooked the positive end to the b- and on the 16 uf i hooked the positive end to the field coil and the ifs is this correct ?this is a battery set so far all i get is a little pop out of the speaker for a second when i hook up the b+ i thought maybe i not hooking the electrolytics right. butch

Butch,

From the schematic you have it right. The 10uF positive side goes to B-. The 16uF positive side goes to the IF primaries and the speaker.

Mike M

:hi i am trying to get a coronado mod. 962 going the electrolytics were missing it has a 10 uf and a 16 uf i have hooked the positive end to the b- and on the 16 uf i hooked the positive end to the field coil and the ifs is this correct ?this is a battery set so far all i get is a little pop out of the speaker for a second when i hook up the b+ i thought maybe i not hooking the electrolytics right. butch

What schematic are you guys looking at? The schematic I am looking at (top one listed for 962, which is in fact the 962), is a battery operated set. The speaker in this set, as I see in the schematic, does not have a field coil. The 10 MFD condenser should be connected with the positive side going to A-, or the chassis, and the negative side going to B-. The 16 MFD condenser should have the positive side connected to B+, and the negative side connected to B-.

Thomas

The cap symbols on the schematic I'm looking at are not clear enough to determine polarity. If B- is the negative side of the B battery, B- would be slightly more positive than ground. If B- is a separate battery then that's a different story.

:What schematic are you guys looking at? The schematic I am looking at (top one listed for 962, which is in fact the 962), is a battery operated set. The speaker in this set, as I see in the schematic, does not have a field coil. The 10 MFD condenser should be connected with the positive side going to A-, or the chassis, and the negative side going to B-. The 16 MFD condenser should have the positive side connected to B+, and the negative side connected to B-.
:
:Thomas

Unless "C" batteries are used within the set, B- is the most negative potential possible within the set. The chassis is slightly more positive than B-, as there is a resistor from B- to the chassis, and various components that go to B+ also tie to the chassis (tubes and the like). This will make the chassis more positive than anything prior to the resistor going from B- to the chassis. Think of the circuit simply as a string of Christmas light bulbs and remember how the voltage reference changes as you go from bulb to bulb down the string.

It is extremely hard for one to shake off the false understanding that ground is always the most negative or neutral item (take, for instance, a positive ground car, in which the positive side of the battery is connected to the chassis). I am saying this from personal experience, as throughout my life others have always explained the notion of ground to me in an incorrect manner. I cannot properly explain it, myself. I do not have words to explain it properly as it is very conceptual. Perhaps with much thought I will someday. Ground, though, is simply a common reference point. The "neutral" wire in your house is neutral because the center tap of the transformer outside of your house is connected to both it and ground. Some people also refer to this wire as the "cold" wire. Since this is alternating current, there is no actual polarity. It just so happens that because this wire and ground are both at the same potential, you won't get a zap between the two of them. The same holds true with antenna circuits. The only reason why the Earth ground plays any role in radio reception at the receiver is because it is also part of the antenna circuit at the transmitter. It will only reference wherever it is placed. It does not have a specific reference point other than that which it is placed in a particular circuit (house, antenna, radio, etc.). You can think of the chassis in your radio in the same way as you think of Earth ground.

On a radio you will find that the chassis, often referred to as ground, is a common place for many components to connect to that require a certain voltage at this particular reference point. For negative grid bias of say the output tube, many radios will place a resistor from the chassis to the cathode of the tube. This will make the cathode more positive than the chassis, thus making the grid of that tube more negative than the cathode. Other radio designs, such as the one in question here, put a resistor in series with the chassis and B-, and connect all items that must reference at the chassis voltage to the chassis. Anything before this resistor, though, will be more netagive than the chassis. Grid biasing resistors may be tied here (as are in this particular schematic), which will effectively bias the grid more negative.

Sorry for getting overly complicated, and I don't know if this one makes sense at all as I explain it, anyway. Should it not make sense, disregard it and perhaps someone else will explain it better in the future.

Thomas

:Unless "C" batteries are used within the set, B- is the most negative potential possible within the set. The chassis is slightly more positive than B-, as there is a resistor from B- to the chassis, and various components that go to B+ also tie to the chassis (tubes and the like). This will make the chassis more positive than anything prior to the resistor going from B- to the chassis. Think of the circuit simply as a string of Christmas light bulbs and remember how the voltage reference changes as you go from bulb to bulb down the string.
:
:It is extremely hard for one to shake off the false understanding that ground is always the most negative or neutral item (take, for instance, a positive ground car, in which the positive side of the battery is connected to the chassis). I am saying this from personal experience, as throughout my life others have always explained the notion of ground to me in an incorrect manner. I cannot properly explain it, myself. I do not have words to explain it properly as it is very conceptual. Perhaps with much thought I will someday. Ground, though, is simply a common reference point. The "neutral" wire in your house is neutral because the center tap of the transformer outside of your house is connected to both it and ground. Some people also refer to this wire as the "cold" wire. Since this is alternating current, there is no actual polarity. It just so happens that because this wire and ground are both at the same potential, you won't get a zap between the two of them. The same holds true with antenna circuits. The only reason why the Earth ground plays any role in radio reception at the receiver is because it is also part of the antenna circuit at the transmitter. It will only reference wherever it is placed. It does not have a specific reference point other than that which it is placed in a particular circuit (house, antenna, radio, etc.). You can think of the chassis in your radio in the same way as you think of Earth ground.
:
:On a radio you will find that the chassis, often referred to as ground, is a common place for many components to connect to that require a certain voltage at this particular reference point. For negative grid bias of say the output tube, many radios will place a resistor from the chassis to the cathode of the tube. This will make the cathode more positive than the chassis, thus making the grid of that tube more negative than the cathode. Other radio designs, such as the one in question here, put a resistor in series with the chassis and B-, and connect all items that must reference at the chassis voltage to the chassis. Anything before this resistor, though, will be more netagive than the chassis. Grid biasing resistors may be tied here (as are in this particular schematic), which will effectively bias the grid more negative.
:
:Sorry for getting overly complicated, and I don't know if this one makes sense at all as I explain it, anyway. Should it not make sense, disregard it and perhaps someone else will explain it better in the future.
:
:Thomas

Ground is just a reference point, it can be positive or negative in relationship to the other voltages. Now, how is that for simple!!

Dave

::Unless "C" batteries are used within the set, B- is the most negative potential possible within the set. The chassis is slightly more positive than B-, as there is a resistor from B- to the chassis, and various components that go to B+ also tie to the chassis (tubes and the like). This will make the chassis more positive than anything prior to the resistor going from B- to the chassis. Think of the circuit simply as a string of Christmas light bulbs and remember how the voltage reference changes as you go from bulb to bulb down the string.
::
::It is extremely hard for one to shake off the false understanding that ground is always the most negative or neutral item (take, for instance, a positive ground car, in which the positive side of the battery is connected to the chassis). I am saying this from personal experience, as throughout my life others have always explained the notion of ground to me in an incorrect manner. I cannot properly explain it, myself. I do not have words to explain it properly as it is very conceptual. Perhaps with much thought I will someday. Ground, though, is simply a common reference point. The "neutral" wire in your house is neutral because the center tap of the transformer outside of your house is connected to both it and ground. Some people also refer to this wire as the "cold" wire. Since this is alternating current, there is no actual polarity. It just so happens that because this wire and ground are both at the same potential, you won't get a zap between the two of them. The same holds true with antenna circuits. The only reason why the Earth ground plays any role in radio reception at the receiver is because it is also part of the antenna circuit at the transmitter. It will only reference wherever it is placed. It does not have a specific reference point other than that which it is placed in a particular circuit (house, antenna, radio, etc.). You can think of the chassis in your radio in the same way as you think of Earth ground.
::
::On a radio you will find that the chassis, often referred to as ground, is a common place for many components to connect to that require a certain voltage at this particular reference point. For negative grid bias of say the output tube, many radios will place a resistor from the chassis to the cathode of the tube. This will make the cathode more positive than the chassis, thus making the grid of that tube more negative than the cathode. Other radio designs, such as the one in question here, put a resistor in series with the chassis and B-, and connect all items that must reference at the chassis voltage to the chassis. Anything before this resistor, though, will be more netagive than the chassis. Grid biasing resistors may be tied here (as are in this particular schematic), which will effectively bias the grid more negative.
::
::Sorry for getting overly complicated, and I don't know if this one makes sense at all as I explain it, anyway. Should it not make sense, disregard it and perhaps someone else will explain it better in the future.
::
::Thomas
:
:
:Ground is just a reference point, it can be positive or negative in relationship to the other voltages. Now, how is that for simple!!
:
:Dave

hi you are right thomas there is no field coil bat. sets never have them anyhow i meant to say the the primary of the output xformer or at least that is what i should have meant.however i seem to have them right so i guess i'll have to look elsewhere for my prob.i am using 10 9 v. batteries for b+ i know they won't last too long but i should hear something at first i heard a lot of microphonics then i changed one of the 1q5s and haven't heard anything since except a very short noise when i first hook up the batteries then nothing i will check plate v. next thanks for all the input. butch

10 9 volts will work well for a while. I use this on my 5-G-500 (Zenith). They last for several hours. If you have the money (really have the money...not the $5 an hour I make), purchase two sets of rechargables and enclose them in a nice cardboard box. Build a power supply with either a 117Z6 tube or a solid state rectifier. Use a 50 K resistor off of the cathodes (perhaps lower, though too low will cause the batteries to over charge). Place a 5 mfd condenser on either side of this. The positive side of each condenser should face the resistor (cathodes--B+), and the negative should go to the return line (the side of the line that isn't connected to the two plates of the 117Z6). Connect your battery (bunch of 9 volts) with the plus going to the resistor (that goes to the cathodes), and your negative going to the return line. Now you can charge and re-use the battery.

Thomas

Maybe 50 K is too much. Try from 5 to 10 K.

:10 9 volts will work well for a while. I use this on my 5-G-500 (Zenith). They last for several hours. If you have the money (really have the money...not the $5 an hour I make), purchase two sets of rechargables and enclose them in a nice cardboard box. Build a power supply with either a 117Z6 tube or a solid state rectifier. Use a 50 K resistor off of the cathodes (perhaps lower, though too low will cause the batteries to over charge). Place a 5 mfd condenser on either side of this. The positive side of each condenser should face the resistor (cathodes--B+), and the negative should go to the return line (the side of the line that isn't connected to the two plates of the 117Z6). Connect your battery (bunch of 9 volts) with the plus going to the resistor (that goes to the cathodes), and your negative going to the return line. Now you can charge and re-use the battery.
:
:Thomas

hi thomas somewhere i found a plan that uses a gell cell or nicads 6v. you then use a a switching device and xformer to make a rechargable power supply of 90 v. and 6 v. filament but as i remember it was too complicated for me.i like your idea better i can afford it as i am a plumber and you know what ripoffs plumbers are. ha ha. butch

You know, unless this is a portable set....I just thought...you'd be better off purchasing the power supply www.tubesandmore.com makes. It's an A/B eliminator. It's not very expensive, either--like $60 or something. It will pay for itself in no time. Just stash it in back of the radio and use the radio like any other. If you wish, you could rewire the filament switch on the radio so that the filament circuit is no longer part of this switch--just disconnect the two wires from the switch and wire them together by themselves. Then run a lamp cord to the filament switch, and connect the other end of this lamp cord so that it switches on and off one side of the cord for the power supply (cut one of the power cord wires and connect each side of the cut wire to one of the wires of the lamp cord). I think that the supply is safe enough to be left on, but I don't like doing that personally. Most modern televisions leave part of the power supply on for the remote control system. This annoys me--wastes power and keeps components powered up that don't need to be. Still, the doorbell transformer in my house has been connected to the supply line since 1942, and nothing bad has happened there.

Thomas

True that! Maybe I should become a philosopher or something, because I can't seem to say something in one sentence.

T.