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 Post subject: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Sun 26, 2018 7:46 pm 
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Location: Ft. Collins, CO.
I need to somehow generate 60 volts from a 1.5v battery (Hoping for AA) in a small space, but here's the big wall: It needs to be analog, no chips, this is something I'm hoping to make.

My first and only thought is a vibrator, but I don't know if 1.5v AA is enough to get anything useful out, and I have no reference for coil sizes for something so low voltage.

This is for a pocket radio system employing subminiatures. I don't want to use a 9V because I'll need to drop the voltage for the heaters, and the 9v is much bulkier.

The tube is a 1.5 volt heater, 60 volt anode.

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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Sun 26, 2018 8:59 pm 
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Joined: Jan Thu 01, 1970 1:00 am
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Location: Livermore, CA
Hi

Best to make an oscillator then step up voltage. If you step up voltage current is reduced. If a circuit is 100% efficient (none are) and draws 100 ma from a 1 1/2 volt battery you would only have 2.5 ma at 60 volts.

A better way would be to use 1 1/2 volts for filament and 9 volt batteries in series to get around 60 volts. It would take around 7 - 9 volt batteries.

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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Mon 27, 2018 12:04 am 
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Location: Oxford, MI
As Norm said batteries will probably be a better option than any kind of step up converter.

The problem is that there is no free lunch. Regardless of the circuit the output power in watts must be equal or less than the input power in watts. I would expect that your radio would draw 3-6mA depending on whether you are trying to drive a speaker or not. For this let's say you need 5mA at 60V, this would be 0.3W. A switching power supply might be able to achieve 80% efficiency, whereas something like a vibrator power supply would probably be closer to 50%. This would be 0.36W or 0.6W respectively and mean that at 1.5V you would need to supply 240mA for a switching supply and 400mA for a vibrator supply.

Now a normal subminiature tube has a 40mA filament. Now again I don't know whether you are trying to drive a speaker and thus have an audio output tube, so your total filament current would be 120mA for a 3 tube set and 160mA for a 4 tube set. Thus you would need a much larger A battery to provide the B+ current for the set.

Since this is a pocket set, space will likely be at a premium. I would think that a better solution would be to save the space used by the converter and use it to house smaller batteries for the B+.

A23 or CR2032 would be good battery choices for a set like this as a stack of them will make up the appropriate voltage and conserve space. A23 are nominally 12V and rated for 55mAh, they would probably last for 7-8 hours in a small set like this. CR2032 are nominally 3V and are rated for 200mAh, and would probably last for more like 20-25 hours in the same application.

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Last edited by Hcompton79 on Aug Sat 31, 2019 10:24 pm, edited 1 time in total.

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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Mon 27, 2018 12:35 am 
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Location: SoCal, 91387
Don't think it's gonna happen with but one 1.5 volt battery. You could string forty 1.5 volt button cells together though, for 60 volts. Plate circuits don't require much in the way of current. eBay sellers from China sell them dirt cheap.

Alternatively, you could do 4-6 twelve volt batteries together. Here's 48 volts for a Koyo, and 72 for a Motorola Pixie;


Attachments:
Koyo rear 1.JPG
Koyo rear 1.JPG [ 183.65 KiB | Viewed 2907 times ]
Motorola Pixie P.S..jpg
Motorola Pixie P.S..jpg [ 119.25 KiB | Viewed 2907 times ]

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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Mon 27, 2018 12:49 am 
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Joined: May Tue 30, 2006 4:46 pm
Posts: 10033
Location: Santa Rosa, CA
CR2032 is rated at over 200 mAh with a 10K load. That's delivering 0.3 mA.

http://www.cr2032.co/cms/prodimages/pan ... asheet.pdf

With a 1K ohm load (3 mA) the mAh is around 100. Not even rated for loads under 1k ohm.

No free lunch is correct. I have built boost converters using Maxim and Linear Tech chips. They really work best at 6 VDC or greater. With a 6 V battery the input current is 60/6 or 10X the output current... if efficiency is 100%,

Rich


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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Mon 27, 2018 2:55 am 
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Joined: Feb Sat 16, 2013 5:08 pm
Posts: 957
Location: Ft. Collins, CO.
Thanks for the input everyone.

I'd have to agree that this is a rather impractical attempt, and that the most realistic system would be to use a battery bank.

I made a quick and simple vibrator unit to test out what I could get out. With 9v at 500mA, it could output 18v 22mA. Horribly inefficient, and the voltage bump is only a double. Much larger, and the unit would be impractical, and just having a battery bank would be smaller.

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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Mon 27, 2018 4:19 am 
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Location: Oxford, MI
Was your radio the Load for that vibrator test? That would seem like a lot of current for a subminiature tube based radio at that low a voltage. Contemporary portables from the late 50's draw about 5.5mA at 45V. By the way, I would very much like to see your radio or at least a schematic, sounds like a very interesting project.

Rich, you are right, I was basing that off memory and should have consulted the data sheet. The CR2032 will still have more capacity and less internal resistance than smaller cells like those that make up an A23 if room will allow.

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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Mon 27, 2018 5:02 pm 
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Joined: Feb Sat 16, 2013 5:08 pm
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Location: Ft. Collins, CO.
Any input as to using this fleaBay unit with a 9v supply?

https://www.ebay.com/itm/DC-DC-8-32V-To ... 0#viTabs_0

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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Mon 27, 2018 6:18 pm 
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We used to make little inverters using the Pico transformers - mostly as "gag zappers" or "tickle sticks". Similar circuits are all over YouTube - penlight cell to 220V, and on down....

https://www.youtube.com/results?sp=SBTq ... v+INVERTER

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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Mon 27, 2018 7:14 pm 
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Joined: Feb Sat 16, 2013 5:08 pm
Posts: 957
Location: Ft. Collins, CO.
Findm-Keepm wrote:
We used to make little inverters using the Pico transformers - mostly as "gag zappers" or "tickle sticks". Similar circuits are all over YouTube - penlight cell to 220V, and on down....

https://www.youtube.com/results?sp=SBTq ... v+INVERTER


EDIT: I tried assembling this but I'm getting nothing out. I didn't have a ferrite ring, so I used an iron core... Might this be the issue?

Thanks, I took a look. I ran into this, which looks like a possibility:

https://www.youtube.com/watch?v=pzVrT0frOJs

Image

The last circuit supposedly puts out 70 volts to the neon lamp. When the neon flashes the voltage drops to 65 and recharges. I don't know how it would perform under constant load, but it might be worth an experiment.

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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Tue 28, 2018 6:40 am 
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Joined: May Tue 30, 2006 4:46 pm
Posts: 10033
Location: Santa Rosa, CA
Quote:
The last circuit supposedly puts out 70 volts to the neon lamp. When the neon flashes the voltage drops to 65 and recharges. I don't know how it would perform under constant load, but it might be worth an experiment.


A neon lamp draws about 1 mA and depletes the capacitor charge pretty quickly. It's a "flasher" and won't provide any significant steady current.

The LED circuits are called "Joule Thief" and actually do work well. A very simple boost converter. Should work with poor efficiency even with an iron core, if the windings are phased correctly.

http://antiqueradios.com/forums/viewtop ... 56&start=0

https://www.youtube.com/watch?v=0GVLnyTdqkg

Rich


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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Tue 28, 2018 10:45 am 
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Joined: Sep Thu 23, 2010 6:37 am
Posts: 12437
Location: Powell River BC Canada
The Bush ETR 82 radio had 1 tube and many transistors. 9 volts was converted to
55 volts for the tube. Here is the circuit description I wrote in the 1965 Radio
Electronics magazine.

It is possible to make vacuum tubes operate in oscillator mode by using
inductors. I have made a blocking oscillator from a 30 tube and a transformer
which is powered by a single 1.5 volt dry cell, that provides both anode and
filament voltage. This was used as the tone oscillator for a spring wound
paper tape code machine. I just eliminated the B battery and used
the parts in the machine.

If your project uses the sub miniature tubes with the very low
filament current like the 1AK4 and 1AK5 you might run some
tests with a volt and a half on the plate, and less on the filament.




Union Carbide held the patents on laminar batteries which were routinely
chopped and hacked into different shapes when needed to fit.

I remember this because employer angered U C and the grouse letter
was sent to my dept to handle.



Attachment:
Bush ETR82 Hybrid RADIO  Radio Electronics 1965  page 106.jpg
Bush ETR82 Hybrid RADIO Radio Electronics 1965 page 106.jpg [ 83.58 KiB | Viewed 2792 times ]

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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Tue 28, 2018 4:36 pm 
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Joined: Sep Tue 30, 2014 6:08 am
Posts: 5666
Location: Norfolk, VA
Here's the simple circuit we used, copied from the aforementioned "Tickle Stick" article in Poplular Electronics magazine:

Attachment:
ticklestick.jpg
ticklestick.jpg [ 37.45 KiB | Viewed 2773 times ]


I've always saved old wall warts to salvage the mini transformers from them, looking for center tapped types. Prior to that, we used to salvage Pico transformers (5K-10K:120 ohms or less, CT) out of old Navy gear to make them. For the transistor, any PNP germanium power type will work - I've used car radio output transistors, 2N1183's, and even some ECG121s.

Rectify the output with a fast rectifier (I use my stash of 1N4935's or R2000's), and filter with a 4.7uf 160V cap, and you can get an idea of what voltage you can get with what transformer. Be careful - I've been shocked a few times making them over the years. Battery life with a D Cell is about 5 hours continuous, no load, so efficiency is probably in the basement, but it's barebones......

The full article is in the Feb '66 Popular Electronics.
https://www.americanradiohistory.com/Ar ... 966-02.pdf

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"Capacitor Cosmetologist since 1979"
USN Retired 1984-2006 (Avionics/Cal)


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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Tue 28, 2018 6:13 pm 
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Joined: May Tue 30, 2006 4:46 pm
Posts: 10033
Location: Santa Rosa, CA
The Tickle Stick is a novel idea for generating microamps of output, but very inefficiently.

--The 2N176 was germanium and germanium will probably work better than silicon at 1.5 V DC

--"Fast" diodes really aren't needed. The thick laminations of steel in a 60HZ wallwart transformer will have huge losses at high frequencies (above a few kilohertz).

Great idea for making a shocking circuit, but not really a steady-state power supply. Similar circuits were used with xenon flash lamps and Radio Shack used to sell a kit of parts with a xenon lamp and HV boost coil.
http://repairfaq.cis.upenn.edu/sam/rslps1.pdf

Rich


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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Sat 31, 2019 8:45 am 
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Joined: Feb Sat 16, 2013 5:08 pm
Posts: 957
Location: Ft. Collins, CO.
I'm sort of reviving this thread, so tag on a new idea.

I'm toying with the idea of the transistor inverter. I built the one I posted about above, snagged from the video. It works alright, and I could get a receiver to pick up a powerful station using it as the B voltage. With a load, the voltage ended up being around 20 volts with 1.5 as the input from a AAA. The idea I'm toying with, is having a similar circuit that relies on a tube instead of a transistor. I'm far from an Electrical Engineer, so as far as I know it's impossible, or been done many times over.

Does someone here know of anything like that?

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http://www.FortCollinsB17.org


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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Aug Sat 31, 2019 7:32 pm 
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Posts: 35459
Location: SoCal, 91387
Here's a converter I built, to boost 9 volts to about 70, and works fine on battery tube portables. Only problem is, it goes through AA's like caca through a Goose.


Attachments:
dcconverter a.jpg
dcconverter a.jpg [ 218.59 KiB | Viewed 1787 times ]

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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Sep Sun 01, 2019 12:47 am 
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Would a 12 volt inverter that puts out 120 ac, work on 6 volts, with an output of 60 vac?

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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Sep Mon 02, 2019 12:19 am 
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Joined: May Tue 30, 2006 4:46 pm
Posts: 10033
Location: Santa Rosa, CA
6V in... Maybe. Depends on the design. A simple transistor oscillator, as shown above might scale OK. If it is a switch-mode IC circuit with feedback... may not work at all. Still, power out = power in + losses. 6V in will demand more battery current to get same power out.

Look for HV supplies for Nixie tubes. Lots of circuits. Still no free lunch, however.

https://desmith.net/NMdS/Electronics/NixiePSU.html

Trying to do a step-up converter with tubes is even more inefficient. You need power for the tube's heater and losses in the tube are higher than for transistors. You won't get a tube to oscillate with 1.5V on the plate!

Rich


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 Post subject: Re: Multiplying Battery Voltage? (DC Step-Up, 1.5 to 60v)
PostPosted: Sep Mon 02, 2019 10:34 pm 
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Joined: Dec Sat 24, 2011 9:17 pm
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Location: Vancouver Island, Canada
I asked would a 12 volt inverter produce 60 vac if run on 6 volts.

Rich, W3HWJ wrote:
6V in... Maybe. Depends on the design. A simple transistor oscillator, as shown above might scale OK. If it is a switch-mode IC circuit with feedback... may not work at all. Still, power out = power in + losses. 6V in will demand more battery current to get same power out.

Look for HV supplies for Nixie tubes. Lots of circuits. Still no free lunch, however.

https://desmith.net/NMdS/Electronics/NixiePSU.html

Trying to do a step-up converter with tubes is even more inefficient. You need power for the tube's heater and losses in the tube are higher than for transistors. You won't get a tube to oscillate with 1.5V on the plate!

Rich
Thanks, Rich. I took a look at the inverter I used to use for home office in the truck. It would keep a laptop battery topped up, but the output has a max amp draw of 22.5 amps @ 120 vac. I recall after about 40 minutes, I'd need to start the engine to bring the car battery back up.

I don't have a suitable 6 volt power supply or battery to test it, but already know it won't work. My 1 amp bench supply won't even charge the caps.

radiotechnician wrote:
The Bush ETR 82 radio had 1 tube and many transistors. 9 volts was converted to
55 volts for the tube. Here is the circuit description I wrote in the 1965 Radio
Electronics magazine.

It is possible to make vacuum tubes operate in oscillator mode by using
inductors. I have made a blocking oscillator from a 30 tube and a transformer
which is powered by a single 1.5 volt dry cell, that provides both anode and
filament voltage. This was used as the tone oscillator for a spring wound
paper tape code machine. I just eliminated the B battery and used
the parts in the machine.

If your project uses the sub miniature tubes with the very low
filament current like the 1AK4 and 1AK5 you might run some
tests with a volt and a half on the plate, and less on the filament.




Union Carbide held the patents on laminar batteries which were routinely
chopped and hacked into different shapes when needed to fit.

I remember this because employer angered U C and the grouse letter
was sent to my dept to handle.



Attachment:
Bush ETR82 Hybrid RADIO Radio Electronics 1965 page 106.jpg


There are some possibilities here. I like the ideas that are proven, not just imagined. :lol:

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Burl Ives, RIP, oldtimer.
[:l>)


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