Just picked up a 1930s Battery operated Coronado

[vortalexfan]

Originally Posted by Electronic M

Both at once...

Are you sure the two batteries should be connected in parallel? Because I'm only getting 1.5 volts connecting them that way...

I've also tried connecting 2 sets of D batteries in parallel and I'm only getting 1.4 volts, so not even close to the correct amount of volts needed to power the radio's filiments...

[vortalexfan]

Well I was able to rig up a temporary battery rig for my radio and it works...Sort of.

I hooked up my signal generator up to the radio and it picks up the 456 kHz IF Signal fine (all though it picks it up all across the whole dial and not just around the 550 area of the dial), and I tweaked the IF cans and surprisingly enough they are peaked where they are supposed to be, I tried adjusting the Oscillator and Antenna adjustments on the tuning capacitor and they didn't seem to make any difference and the 600 kHz oscillator adjustment is under the chassis so I couldn't adjust that.

But I can't get it to pick up any radio stations I can't even get it to pick anything up from my signal generator tuned to various stations on the AM Band, hooked through the antenna, and the antenna coil tested fine when I tested it.

Any ideas as to what may be going on?

[Electronic M]

Originally Posted by vortalexfan

Are you sure the two batteries should be connected in parallel? Because I'm only getting 1.5 volts connecting them that way...

I've also tried connecting 2 sets of D batteries in parallel and I'm only getting 1.4 volts, so not even close to the correct amount of volts needed to power the radio's filiments...

Note I didn't advise you to put the batteries in parallel....I only advised you HOW to connect them in parallel.
The trouble with using standard alkaline D cells to supply the 2.2V filaments is that new alkaline cells are 1.5V so parallel will not give you enough voltage and series will give you too much (unless you use used batteries that are down to ~1V ). The only advantage of parallel connection is that the batteries will last longer.
One thing you could do for the filaments is connect the batteries in series and build a LM317 circuit to regulate 3V down to 2V...A filament rheostat is another solution.

Got an oscilloscope to check if the converter or oscillator tube is oscillating? And do you have a decent length of antenna wire 15-40' hooked up? If you have an antenna and the IF works then either the local osc is dead or the RF path between the antenna and the Mixer/Converter is bad....If you passed IF down the antenna and it didn't seem attenuated in comparison to injecting it at the 1st IF then that favors the Osc being dead.

[fixmeplease]

Ive done a few of these 90V but the filament was 1.5v. Anyway I use 60 AA batteries for 90V power. I have soldered in connections for 45V too for other radios. I doubt the AA's cost much more than the 9V ones but you have to solder holders together and yes more time involved. About every 3 years +/- 1 they need replacing if they are a good brand.

I like the sound of the battery radios. They dont have much static type sounds as they arent hooked to your homes power supply. If your fortunate enough to have a long wire antenna that will increase the sound too. My outdoor antenna is about 90 feet long.

[dieseljeep]

Originally Posted by fixmeplease

Ive done a few of these 90V but the filament was 1.5v. Anyway I use 60 AA batteries for 90V power. I have soldered in connections for 45V too for other radios. I doubt the AA's cost much more than the 9V ones but you have to solder holders together and yes more time involved. About every 3 years +/- 1 they need replacing if they are a good brand.

I like the sound of the battery radios. They dont have much static type sounds as they arent hooked to your homes power supply. If your fortunate enough to have a long wire antenna that will increase the sound too. My outdoor antenna is about 90 feet long.

Reminds me of what I did in the mid-50's. I would dig through the trash bin behind the TV shop for battery packs for a Zenith TO or similar. The "A" side was usually dead, but the "B" side was good for about 75 or so volts.
That side was usually sealed in tar and lasted quite a while.

[fixmeplease]

American ingenuity!

I did forget to add that the smaller voltage battery will often just last hours as they have draw. The 90 volt pack will last for the life of the batteries. I did buy a cheap brand of AA's and I got what I paid for, they lasted about a year.

[dieseljeep]

Originally Posted by fixmeplease

American ingenuity!

I did forget to add that the smaller voltage battery will often just last hours as they have draw. The 90 volt pack will last for the life of the batteries. I did buy a cheap brand of AA's and I got what I paid for, they lasted about a year.

On a side note and slightly OOT, it always amazed me that anyone would buy a battery only tube radio. "B" batteries were never cheap!
I'm referring to the time when most homes had electricity. Portable, battery only radios were made until about 1956.
Three way portables were only about $5 to $8 dollars more and you can use them all year.

[jr_tech]

Originally Posted by dieseljeep

On a side note and slightly OOT, it always amazed me that anyone would buy a battery only tube radio. "B" batteries were never cheap!
I'm referring to the time when most homes had electricity. Portable, battery only radios were made until about 1956.
Three way portables were only about $5 to $8 dollars more and you can use them all year.

In my case, it was for safety... as a kid, I was always taking my radio into the bathroom, a battery only set with no cord was much safer. “B” batteries were great xmas and birthday gifts

jr

[mr_rye89]

My step mom has a Coronado set that has three way power. it had a compartment and a plug for a 90V/1.5v A/B battery (i think). I think it was late 40s or early 50s. I'll find more info next time I visit.

I also have an Emerson 508 (battery only) and a Motorola 5A7A (three way) that use a 67 volt B and a D size A.

EDIT: nabbed photos off epay. empty box lol.

two 45 volt "B"s and two 4.5 volt "A"s. hmmmm.......

[dieseljeep]

Originally Posted by mr_rye89

My step mom has a Coronado set that has three way power. it had a compartment and a plug for a 90V/1.5v A/B battery (i think). I think it was late 40s or early 50s. I'll find more info next time I visit.

I also have an Emerson 508 (battery only) and a Motorola 5A7A (three way) that use a 67 volt B and a D size A.

EDIT: nabbed photos off epay. empty box lol.

two 45 volt "B"s and two 4.5 volt "A"s. hmmmm.......

The radio was made by Warwick. I wonder what battery life was like? Using a 9 volts "A" source makes the switching circuitry simpler between line and battery.
My luggable Emerson 523 uses the same battery compliment.

[vortalexfan]

OK so a little update on this radio, I got the radio recapped yesterday and I also got a set of 2500 mAH NiMH rechargeable D batteries from Harbor Freight and then a Charger for them at Menard's (they were the only place near me that had a universal battery charger in stock without having to travel to Mishawaka or South Bend which is over a half hour away from me.)

And I charged the batteries over night and installed them into my battery clip and turned on my radio with my signal generator hooked up to the antenna wire and sure enough I was signal through (albeit at the wrong frequency, it was coming in at 453 kHz rather than 456 kHz) and so I realigned the IF cans so that they were coming in at 456 kHz instead.

But then shortly after that the radio faded out and I checked my D batteries for my "A" supply and they were still putting out a charge so then I turned the radio back on again and the radio started working again but then it faded out again.

Also something I've noticed with my radio is that one of the IF cans on this radio is a replacement and when I would power on this radio and once it warms up, the radio makes a short burst of white noise and then it goes away like the radio is trying to pick some stations or trying to function but it can't quite function properly.

Also another weird thing I've noticed about this radio is that this radio will only operate at between 2.2 volts and 2.4 V on the filaments, if I try to use the recommended 2.1 Volts, the radio won't operate.

Any ideas as to what might be going on with the radio?

[dieseljeep]

Originally Posted by vortalexfan

OK so a little update on this radio, I got the radio recapped yesterday and I also got a set of 2500 mAH NiMH rechargeable D batteries from Harbor Freight and then a Charger for them at Menard's (they were the only place near me that had a universal battery charger in stock without having to travel to Mishawaka or South Bend which is over a half hour away from me.)

And I charged the batteries over night and installed them into my battery clip and turned on my radio with my signal generator hooked up to the antenna wire and sure enough I was signal through (albeit at the wrong frequency, it was coming in at 453 kHz rather than 456 kHz) and so I realigned the IF cans so that they were coming in at 456 kHz instead.

But then shortly after that the radio faded out and I checked my D batteries for my "A" supply and they were still putting out a charge so then I turned the radio back on again and the radio started working again but then it faded out again.

Also something I've noticed with my radio is that one of the IF cans on this radio is a replacement and when I would power on this radio and once it warms up, the radio makes a short burst of white noise and then it goes away like the radio is trying to pick some stations or trying to function but it can't quite function properly.

Also another weird thing I've noticed about this radio is that this radio will only operate at between 2.2 volts and 2.4 V on the filaments, if I try to use the recommended 2.1 Volts, the radio won't operate.

Any ideas as to what might be going on with the radio?

First of all, a fully charged 2 volt lead-acid puts out 2.2volts. This voltage is what the radio was designed to use.
Did you check the tubes on a good tube checker. You probably have a weak osc-mixer tube. Increasing the filament voltage, will increase the emission.

[fixmeplease]

Originally Posted by dieseljeep

On a side note and slightly OOT, it always amazed me that anyone would buy a battery only tube radio. "B" batteries were never cheap!
I'm referring to the time when most homes had electricity. Portable, battery only radios were made until about 1956.
Three way portables were only about $5 to $8 dollars more and you can use them all year.

The 1st one I fixed was my Dad's farm set before they had electric. Its a 1949 I think. Airline model. My Dad told me even back then the batteries were expensive. They used it until quite a while after they got electric then gave it to an Uncle who had electric but no radio and he used it until around 1960 I think.

It needed and needs a decent antenna run to pick up much, maybe 10 foot minimum so isnt much of a portable. It only has a screw to attach an antenna wire to it. A built in antenna would have been better. My Dad ran an antenna around the outside of the house and stapled it on so they could listen to the Grand Ole Opry on the weekends, plus local stations during the week.

All that said, I agree, anyone with electric was better off with a plug in electric option.

[dieseljeep]

Originally Posted by fixmeplease

The 1st one I fixed was my Dad's farm set before they had electric. Its a 1949 I think. Airline model. My Dad told me even back then the batteries were expensive. They used it until quite a while after they got electric then gave it to an Uncle who had electric but no radio and he used it until around 1960 I think.

It needed and needs a decent antenna run to pick up much, maybe 10 foot minimum so isnt much of a portable. It only has a screw to attach an antenna wire to it. A built in antenna would have been better. My Dad ran an antenna around the outside of the house and stapled it on so they could listen to the Grand Ole Opry on the weekends, plus local stations during the week.

All that said, I agree, anyone with electric was better off with a plug in electric option.

I have a post-war Zenith four tube farm set.
I got lucky and picked up two battery eliminators intended for farm sets at a swap meet a while back. I have one in the Zenith.

[vortalexfan]

OK so I had ordered some capacitors for this radio over at AES (Antique Electronic Supply) and I had put the order in on Friday (November 27) and I had gotten the order confirmation email from them on Sunday (November 29) and I checked the tracking on my package and it says that a shipping label was made for my order on November 29 (Sunday) and that the postal service was waiting to receive the package, and that's the last update on my parts order from AES.

Here it is December 2, and its still not left AES's headquarters, (according to the tracking number as of today) and I paid the extra money for priority mail.

Does anyone know what's going on?