[SOLVED] Powering a battery only device with house power.

Hi,

I am new to this forum and my electronics background is a few years of daily classes way back in high school (not much and a long time ago too) so please bear with me here. Thanks.

I have a need to purchase a biofeedback machine to train myself to habitually reduce muscle tension in my shoulders (etc) and eventually control heart rate during market trading. In short it is stress reduction basically and for those who are not aware of it "stress really does kill mainly by raising your cholesterol levels even if you have an absolutely perfect diet so this is actually very important". This machine will run 35 hours a week at least. I just found out that all of these machines run on batteries (I gather you have to spend $4,000 or so to get ones that do not). At 35 hours of use a week obviously even rechargeable batteries are out of the question. Some of the better ones use simple C cell type batteries. Not being one who is very good at giving up, I am wondering if I could find an AC adapter and solder the output of the adapter to the battery contacts. I created this post because I vaguely seem to remember trying something like this once and I could not get it to work so I do not want to buy a machine unless I am pretty sure I can get this to work. Is there a trick to doing this. Do I have to ensure the current is the same in addition to the voltage? (makes sense actually).

Thanks,
John

Short answer, Yes it is possible.

Long answer: Can be done but you will need to meassure what the battery configuration of the machine is before anybody can tell you how to connect it.
Depending on the current requirement, for the amount of hours you are going to use the machine you will be looking at buying a AC adaptor which contains a SMPS. Similar to a laptop charger.

@bowlesj

I read Your post. I have to say several things, but only like my wide opinion.

1. We up to date with current date dont know much about influence of stress on body. We link stress with everything and when we dont have solution and cause of some state of body and cells we give easy answers and point with finger in some speculative thing. Just look what circus is made in world with Omega 3, people like ships buy foods with Omega 3 and now after some time there is some scientific research about this which give us negative results about that. The same thing is with olive oil and usage in human nutrition, in the background of some countries which have big production of olive.

2. You can use rechargable batteries You have to buy 4000mAh AA NiMH in shops. Buy two sets if You need. Use portable little solar charger for that batteries if you longer out or charge batteries in car.

3. Dont play with electronics near heart and brain, I think this is not healthy.

4. Do not pretend to be smarten then Your Grandparents, which have healtier and longer life then we todays with all of this medicals high tech.

5. Go out in nature on fresh air, and get out all tech from ears, such iPods and handsfree devices.

On market I saw on market some devices called vitafons or something like that, and also I have one relative which buy one of better device from this family of product. What to say, I just have smile on face, when saw specification of this device. They penetrate with 22KHz acustic vibration into tissue on adjusting deep and healing cells of some particular organ. :grin: After some time I get some circuit and it just multivibrator-oscillator circuit. :grin: Of course all with lots of "some" certificate about medical testing.... :grin: Just see what GHz you need to penetrate into tissue on what deep (medical ultra sound sonde).

:roll:

Thanks guys, I have entered some of your info in my to-do list for followup.
John

And yes, dont use mains adapters for such devices, lets say "medical" devices with body in touch.

Strongly consider usage on batteries.

Safety on first place.

You cant count on some PSU from market maded in China or who knows where.

:wink:

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This is september, 2012. and such devices is selling freely without no consequences.

This reminded me of the Dell Boy:
https://www.youtube.com/watch?v=k5hJSLfhTqE

Thanks. for sure one would want a reputable power source and maybe a fast blow fuse could be rigged up (one like I had in my old Akai reel-to-reel tape recorder.

bowlesj said:

Thanks. for sure one would want a reputable power source and maybe a fast blow fuse could be rigged up (one like I had in my old Akai reel-to-reel tape recorder.

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No this is not safe, design must be isolated if there is some conductive contact with body in touch.

Yes I have to admit I have not researched it. I do know that years back I was sleeping and lightning hit near the house. It woke me up rather suddenly. I went to my equipment to unplug it but it was too late. I had a Panasonic receiver and an Akai reel-to-reel on the same house circuit. The Panasonic had a slow blow fuse and the transistors got fried (even the repair shop could not fix it properly). The Akai had fast blow thin fuse (current Limiting fuse) and they blew and the machine was fine. It had a spare, I popped it in and 30 some years later it still worked before I sold it. So considering that all things are relative and considering that man has been to the moon I believe that such as fuse could be created to protect humans from house powered (AC powered) biofeedback machines (between the house simulated battery and the body or maybe between the machine and the body in the electrode body wires themselves). So if it is not safe then it is only because there is not enough market to create such a device. I also know that I was at a profession therapy once and they had me stick my feet in water and there were wires to pads or something causing my muscles to move (muscle stimulators). It was a professional machine. The law permitted it and if the law is always correct then my theory that such fuses exist may in fact be true. However, I have not researched it so I can not say for sure. I would have to research the amount of current it takes to hurt or kill a person (when they are not well grounded) then see if there are fast acting fuses with such low current limits. I can't to this tomorrow because I have to go for an angiogram due to enduring 11 years of stress - LOL - I should not laugh because it almost killed me. My research shows that constant stress increases your cholesterol and if that has blocked a heart vein at lets say 90% and the thickening of blood that is the immediate impact of stress in the here and now (very easy for researchers to prove) should interact with that 90% blockage it could be very dangerous too (very hard to predict when the D-Day comes unfortunately). Constant stress also impacts digestion and immune system. I an not sure how dangerous this is. Stress is much harder to nail in terms of danger than man made electrical devices because people can appear stressed and they are not and the inverse is true as well. I gather it has to do with how their hormones change during stress and that probably varies across people.

Pro medical equipment have isolation of electrodes. Example ECG electrodes.

So the isolation allows just the correct amount of current/voltage to come through and no more? Kind of like a fuse with a guarantee attached I guess.

Yes, I have been hooked up to an ECG many times. Had about 6 actual stress tests. Interesting machines. The 3rd last time I was on one of the stress tests they operator told me to look at my heart beat. I saw it had a sort of anomaly in the wave. He told me to relax my hands on the handles. I did that and the wave immediately smoothed out. I will never forget that and it was the first time I saw that a change in stress immediately has an impact on the heart. The body is very complex and has lots of electricity going on for sure. It probably had to do with the heart having trouble pumping blood through those tight muscles and much less trouble when I released my tight grip (not that hard to understand actually). However it may have an electricity component to it as well since if you listen closely to a muscle when you grip tight (your palm) it is firing electricity very fast (you can hear it very clearly). This is what the muscle tension sensors are reading.

I told my family doctor that when I walk across the street then I have a little pain in my upper chest. My doc said it is not my heart up there.
Two months later after walking quickly up and down the stairs at home I had a serious and painful heart attack. If I was out walking my dogs then I would have died.
My wife quickly drove me to the local hospital and at first they gave drugs to free my arteries then an Angiogram showed two blocked arteries feeding my heart, they quickly did two Angioplasty operations (and I watched!) where a mesh metal tube was fed into the large artery in my groin then expanded at the blockage with a balloon.

They fixed me fast so there was no damage to my heart and now I am fine (taking anti-cholerestrol medication).
Stress?? I am retired so every day is a Saturday. I do whatever i want whenever I want.
The government pays me a pension and other goodies for playing around.

My Cardiologist (heart doc) says he wants to see me in 2 years and it will probably be the last time he sees me (it sounded bad then he said I graduated and I am fine).

All the ECG tests I had were made with certified safe medical manufacturers so I was never electrocuted.
Can you imagine a do-it-yourself ECG unit electrocuting somebody?

Yeah, the nerves of various parts of the body apparently cross over the heart nerves and somehow the signals get transferred across nerves. So the pains can be directly at the heart and in all sorts of strange locations (mostly on the left side but sometimes on the right). Some people have no pain at all until it is too late. I realize this is off topic but hey, the heart is electrical and maybe someone will live longer reading it. I also had palpitations caused mostly by coffee (caffeine). 24 hour monitor showed 3,000 a day. I just completely quit coffee/caffeine. I am now down to 34 or so a day. Amazing drop. In some people caffeine causes extra electrical signals to go to the heart. Stress also effects palpitations (increases them). They are not dangerous until you get too many in a row but I say one should get them checked out regardless.

See this location :

https://homepages.cae.wisc.edu/~bme200/eeg_biofeedback_f06/

Thanks Tpetar,

I am thinking maybe I can pick up a good used pro machine at a reasonable cost or just a low end 2 sensor machine. A person at one company suggested a small motorcycle battery.

John

Motorcycle battery is lead acid probably 4ah, 6Ah, 7,2Ah or 9Ah its too heavy for portable device. Better go with NiMh with two sets. But You can try different variant why not, You can try Lead Acid first if all ok, then proceed with usage. ;-)

Audioguru said:

They fixed me fast so there was no damage to my heart and now I am fine (taking anti-cholerestrol medication).

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That is great to hear. I think most plugged heart veins are food related but some are stress related and of course some are both. I had no idea that stress increased cholesterol until this last Friday. I have been eating an exceptional diet for 7 years. In my case it is clearly a stress issue. Changes are in order. anti-cholerestrol medication and aspirin are also in the works for sure. The heart doctor said to me "once your heart veins are plugged you have to be very aggressive at keeping your cholesterol down". I tell my daughter to do it now. Why wait. It is smart to learn from the mistakes of others and I tell her this. I thought my great diet would protect me. It helped but it was not enough.

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tpetar said:

Motorcycle battery is lead acid probably 4ah, 6Ah, 7,2Ah or 9Ah its too heavy for portable device. Better go with NiMh with two sets. But You can try different variant why not, You can try Lead Acid first if all ok, then proceed with usage. ;-)

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Yes, years ago I used NiMh with two sets (exactly what you were saying). I had a routine. I know it well. It was for a CD player. I was working overnight on weekends in security keeping the boredom away while trading the market during the day weekdays. I am trying to remember. I think I only had it running on batteries for about an hour each night (during patrol) and the rest of the time I was listening to the radio. I am just thinking that 35 hours use (7 hours a day 5 days a week) is just going to be too much of a hastle with that old routine. if I must, I must, but I still think I will see if I can get a used pro biofeedback machine first. by the way, it is not portable use. it will always be on the desk in the same location (ALWAYS).

I can lower my blood pressure just by thinking, Relax, Relax, Relax. Some people call it meditation. So I don't need a biofeedback device.

Audioguru said:

I can lower my blood pressure just by thinking, Relax, Relax, Relax. Some people call it meditation. So I don't need a biofeedback device.

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That's great! It inspires me. I do not have time for outside hours meditation nor time during the trading day to stop and think a repeat word like that but I figure that if I am wired 35 hours a week and being constantly reminded to relax those muscles etc, I should eventually develop the habit at an automatic level Maybe I can break some sort of Guinness book of world records for the most relaxed person However the current world record holder is probably asleep all the time - LOL. Anyway, I am thankful for electronic devices that can help us develop new habits. I guess if it falters and sends too much current/voltage it would not be all that relaxing

A late update. The solution to this problem was buying a blood pressure monitor which is probably the really important reading anyway. Most (if not all) of these have AC adapters which is what I want. The one I am choosing can upload to computer software via USB and I can export the data in CSV (comma separated value) format to my database program for analysis by groupings. I can also get a heart pulse rate reading. In addition I have regular voice reminders to relax. The other good part is the price (about $110 for this more advanced system).

I had another blood pressure test at my cardiologist's office. It squished my arm so bad that it became very badly bruised, swollen and painful.
The bruise travelled all over my arm in a few days so I was sent to the hospital where they did some ultrasound videos and photos. Nothing needs to be repaired but it will heal on its own in a few weeks. It has been almost 2 weeks and it still looks bad but feels much better.