Just picked up a 1930s Battery operated Coronado

[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.

[vortalexfan]

Originally Posted by dieseljeep

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.

I was using a set of 1.2 V NiMH rechargeable D Cells, not the 2V Lead-Acid battery I had previously linked here and asked about.

Secondly I don't have a tube tester capable of testing the old style 4, 5, 6 and 7 pin tubes, so I can't check the tubes unfortunately.

I've tried to acquire one but everytime I find one they usually want over $100 for it, which I can't afford anything like that right now.

[Kevin Kuehn]

Since your set has AVC why not monitor that voltage to get a handle on what's going on? You'll want to use a VTVM, a scope, or a digital volt meter connected to the bottom side of R3(2meg). When the set is working does your AVC voltage seem to work normally with and without a signal tuned in? AVC voltage normally will be negative with a strong signal and become more positive as you de-tune the station. If the local oscillator isn't running you loose AVC action. If AVC voltage continues to respond to tuning then when the audio fades, then most likely you have an issue in the audio sections. When the radio is working correctly you can also align the IF's to the most negative voltage on the AVC line. There's really no need to rely on listening to an audio tone through the speaker.

Edit R3 not R4

[Kevin Kuehn]

I meant AVC voltage at bottom side of R3, not R4 as I fist posted.
Edited above post.

[vortalexfan]

Originally Posted by Kevin Kuehn

Since your set has AVC why not monitor that voltage to get a handle on what's going on? You'll want to use a VTVM, a scope, or a digital volt meter connected to the bottom side of R3(2meg). When the set is working does your AVC voltage seem to work normally with and without a signal tuned in? AVC voltage normally will be negative with a strong signal and become more positive as you de-tune the station. If the local oscillator isn't running you loose AVC action. If AVC voltage continues to respond to tuning then when the audio fades, then most likely you have an issue in the audio sections. When the radio is working correctly you can also align the IF's to the most negative voltage on the AVC line. There's really no need to rely on listening to an audio tone through the speaker.

Edit R3 not R4

I did check the voltage at the AVC line resistor (R3) and it does respond like its supposed to but the audio is not very loud unless I use my signal generator's "HI" output connection, and then it comes out at a more "normal" volume level.

I have attributed that fact to what I believe is a faulty 1C6 Tube, because the oscillator seems to be "running" but not very well, and both 1A4 tubes respond with a hum when I touch their grid caps but nothing when I touch the grid cap on the 1C6, I get no hum out of it.

So I'm thinking I'm on the right track and just about have this thing going.

[init4fun]

Originally Posted by vortalexfan

I was using a set of 1.2 V NiMH rechargeable D Cells.....

Looking at the tube compliment posted in your first post , I can not believe a pair if D cells in series is anywhere close to powerful enough to light all those filaments .

[vortalexfan]

Originally Posted by init4fun

Looking at the tube compliment posted in your first post , I can not believe a pair if D cells in series is anywhere close to powerful enough to light all those filaments .

They are 2500 mAh batteries, so more than enough juice to power the filaments (the filaments require around 540 mA).

[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?