Inverting 12v to 120v

I₁V₁=I₂V₂

So if you increase 12V to 120V (10x) your current will be reduced to 1/10th.

It would be more complete to say,

I₂V₂= ηI₁V₁, where η is the efficiency of your inverting mechanism (in the range from 0 to 1).

So, for an inverter that is 75% efficient,

I₂ = (.75)I₁V₁/V₂

I hardly ever get to say η anymore.

If the power in is the same as the power out, roughly, then the current needed at the 12 volt side is 10 times what the output current is at 120 volts.

It will be a little more due to losses.

Power in = Vout/Vin x Power out for resistive loads.

Say: power in = 120 watts @ 12 volts > Iin = 10 amps

Power out = 120 watts @ 120 volts > I out = 1 amp.

DANG IT! Now I know why my "deep cycle" 12V marine battery had a meltdown when I connected that welder to the inverter!

What in the world is a Farad anyway?

I don't see how that applies to this:

True story guys:

As a young teen (in the fifties) I had a 48 Chevy. Had an AM radio, but not many stations that could be picked up.

I had acquired a 12V to 120/240 V inverter somewhere along the line. I, as many or us back then did, had a portable turntable (for younger folks, a RECORD PLAYER). 45s were big then. Elvis's "Hound Dog" and "Love me tender" were gold. Anyway, I had the bright idea of putting the record player in the back seat and spinning a disc while me and girlfriend were smooching. It gets better!

On the way to pick her up I thought I'd try it out. I placed the record on the turntable, then drove off slowly ready to place the needle on the record. I reached back and switched the inverter on- to the 220 V position! What followed was smoke galore!

That record player became instant toast. I think I called my girlfriend and made up some lame excuse why I had to cancel since I had told her of some new and exciting invention I had.

(A lesson in what not to do with an inverter)

I remember a car that came out back in Elvistime that had a fold down 45 player under the dash. You should have got one of those - it was the cat's pajamas.

I have never heard of that one. Do you recall make & model? Just curious.

Wouldn't have made a lot of difference at the time though. Was barely able to afford those 45's. Me & best friend saved/scrounged up $25 to buy a guitar. We shared, and learned together, to play basic chords like C, F & G^7th so we could play songs like "Love me Tender", "Raunchy", etc.

True story: Me and said best friend actually used liquid black shoe polish to dye our hair for that "Elvis" look (well, really, to impress the girls). I understand that there are, to this day, pics floating around of that episode.

Just because you asked(?), we did not pick up a date with our dyed hair! We did, however, get four people in the trunk, and pay for two, to get into the Drive-in movie (of course it it was an Elvis movie, what else).

Believe it or not, we kids had real fun!

-John

I don't remember the model, but a quick google came across a site that purports to repair those old things.

And I found this:

Automobile Phonograph

In 1955, an automobile phonograph system was developed.
57 A special 7-in record, turning at 162 rpm, and
containing up to 45 minutes of music, or one hour of
speech on each side was used. 500 and 600 grooves/in
were employed and the stylus of 41-mil radius exerted a
force of approximately 2 grams on the disk. The pickup
cartridge was mounted in a balanced and heavily
damped arm, and pivoted to permit handling records
without scratching. The phonograph was suspended on
elastic mounts to permit operation in the moving
vehicle.

Most interesting.

"The pickup cartridge was mounted in a balanced and heavily
damped arm, and pivoted to permit handling records
without scratching. The phonograph was suspended on
elastic mounts to permit operation in the moving
vehicle."

I had actually tried mine stationary at the proper 110 V setting before I blew it up on 220 V while driving. I realized that keeping the needle in the groove would be a problem so I taped two pennies to the arm before driving off into the record player sunset.

Looks like the guys you mentioned put a little bit more forethought into it. BUT, we were but teenagers once!

-John

Chrysler (who else?) offered it on the 1956 models. Here's a link.

Yeah - that's the ticket. Interesting comments in that article, too.

I just went back and read a lot of the comments on the link. As you say, a lot of interesting comments there. I did not know about those things that went on. Must have been preoccupied with life or something.

Thanks CSM for the link.

"Alas, problems abounded with the system: Records skipped as the car encountered uneven surfaces. And an exclusive content arrangement with Columbia meant that drivers could listen only to artists signed to Columbia Records."

As noted by the experts, record skipping was a genuine problem. Before my player's untimely demise, as I said earlier, I did conquer, somewhat, with the two penny solution. I think I failed to mention earlier that I did test drive the 1950 Oldsmobile with back seat record player, with the weighted needle arm, successfully before driving off for my never-to-be date because of my $%*&*5** carelessness! Needless to say, I did not score that day!

thank you very much!

what u need is a DC to AC step up transformer, dont woory about the ampere rating the unit can withstand it a.

Good thing that I am reading, from time to time, this forum. I tried to supply a record player with a DC to AC step up transformer, but it seems that I didn't use the right voltage. I connected a 12V battery to the primary and, after a minute or so, it started to smoke. My taylor told me that I should have used a 8.8V batttery.

One question regarding the aforementioned "record player":

Where in the world would a teen, intent on impressing a lovely date, with a newfound invention, POSSIBLY locate an 8.8V battery??? Wait! I didn't think about Mars! At that time aliens were suspected of, perhaps, be hanging out there. They probably hoarded all those 8.8V batteries for use in their ion engines. Wellll, they had to be somewhere didn't they?