And so the one I happened to pull off and test was a PNP transistor? It has both.

 

The circuits are different:

 

The only thing is the ground side is different

The schematic in post #140 doesn't show the two emitters as being connected to ground, but I think they should be.

 

I looked at both schematics AG and it does show two transformers. I did say there were slight differences. The pic I posted on page 7 is actual.
Thanks Alec_t if you look at the pic of the components on page 7 at the top is the ground. there are only (4) components: a resistor, two diodes, and a capacitor. the capacitor is a 15V 20-80 which from what I can tell is no longer made, unless it's a VAC capacitor" I'm still learning" . the two diodes are Zener and I have the specs for the resistor somewhere but not at hand.
and I also forgot to tell you "thank you" So I'll tell you now. you have answered before and it is appreciated.

 

The schematic in post #140 is drawn wrong because it is missing the connection dots for the emitters at ground and also at each end of R1.
I have never seen a schematic of the MindBlower speaker with an output transformer. The patent is the only schematic I have seen and it has a custom-made speaker with a center-tap (3 wires).

 

I'm not trying to say anything bad about what you said AG. The big difference I see is in the schematic bertus posted the two emitters are not connected as shown. there is a capacitor connected across the plus and minus of the emitters. again I did say there were differences. Don't know if this makes it work the same or not still reading. the part in the pic that looks like something wrong on the board (left) is a capacitor sticking up. should have pushed it down for clarity. It says ZSF or Z5F no other markings on the back. I'm just trying to understand AG. I do appreciate your help and everybody else's I'm working on the schematic in Diptrace AG just give me a little time "I'm a Newbie".

 

I could post a "sketch" AG it has exactly how the schematic (wiring) goes. again not real great at Diptrace yet. I figured when I learned what was going on I would show everyone. never been a pic person on the computer, I just fixed them. got into it early when I wanted to do arcade emulation, another one of my hobbies. I loved the old defender and stargate games so much I built my own.

 

II added the solder joints that were missing from the schematic Bertus posted:

 

I will try my best today to give a shot at making a Diptrace schematic that shows what it looks like.

 

@ Berzerker. Do you have any of the advertising or a catalog page describing the MindBlower? Some times just seeing how it was described or promoted can help in figuring things out, what it was meant to do. And using that maybe you can get a more modern way of doing the same thing.

With the little I know about it it seems to be a cross over that can amplify a certain frequency range when it is turned on. But then again I could/am wrong.

 

Scroll down here:
https://www.thegearpage.net/board/i...d-some-people-play-their-car-stereos.1712397/
This is a pair with an equalizer. but I never bought this kind cos the plant here went out before they had them.
Here is a pic from the back:
https://www.google.com/search?q=min...wKHX9eBKcQ9QEwCnoECAMQBA#imgrc=qkZ4YZmxe3Ax5M:

 

The ad claimed 60W RMS (30W RMS per speaker) that is just a little louder than an ordinary 14W RMS per channel car radio since the sensitivity of our hearing is logarithmic then 10 times the power sounds twice as loud. Actually, car radios have four speakers at 14W each which sounds the same level as a pair of Mindblower speakers.
An equalizer is needed if the speakers have a very uneven frequency response or you want a good speaker to have a very uneven frequency response (you are old and cannot hear high frequencies any more?).

 

Back then I had a stereo with an 5 band equalizer built in. And if they were only 30 watts, it was the loudest 30 I ever hear. I had people turning their heads to see where it was coming from. you could hear it blocks away. and I also know they had different wattages, different speaker configurations cos the last pair I bought had 100 watts on the package.

 

The ads cheat. 100 peak or "maximum" watts are actually only 50 real (RMS) watts but at a horribly high distortion. It might be only 30W or 40W at a reasonably low distortion because the distortion creates additional Watts.

Some cheap speakers have loud peaks at a few frequencies which might be in the speech range then they sound louder than a good speaker that has a flat frequency response. Also cheap speakers have a smaller gap between the voice coil and the magnet for higher sensitivity but soon the coil sags and scrapes against the magnet causing noises. "Cheap" means short life and problems.

 

40 years ago my after-market car radio had one of the first compact cassette recorder-players. It was loud enough, maybe only 4W per channel (2 channels) because it did not use a modern amplifier IC and its amplifiers were not bridged. 30W from a MindBlower speaker and 60W from two of them would sound noticeably louder. But modern 56W car radios don't need it.

Maybe newer Mindblower speakers can be made and sold to the few old guys who still drive 40 years old cars!

 

If redesigned I took into account I would have to make them more powerful and would have to allow for the newer higher wattage stereo inputs or use the low level inputs or put some components in to reduce the input wattage so the amp could handle it. I think the spec sheet said not more than 10 watts input when I read how to install them. They claimed 10 times the (power) if I read the pic I posted of the ad right. 10X10= 100 watts. If you input 3 watts you got 30, if you input 5 you got 50. I think the transformer amplified (times) the input wattage.

Are special power amplifiers that magnify any car stereo or radio up to 10 times

 

From my understanding of how a step up transformer works it amplifies input. If you have a transformer that doubles your input let's say a 12 to 24 volt input transformer. If you input 12 volts on it and wire it correct you get 24 volts. Now if you input 24 volts you don't still get just 24 volts you get 48 volts.

 

A transformer is designed to handle a certain amount of power. Output power is always a bit less than input power, because of inefficiency. A transformer cannot amplify power.
Suppose you have a 6W rated transformer with a 1:2 turns ratio. If you put in 12V 6V you will get out 12V, but the maximum current from the output is 6W/12V = 0.5A. If you put in 12V you will get out 24V but the current will be less, i.e. 6W/24V = 0.25A.

 

I'm probably wrong again Alec_t. I get my info from places like this and have to interpret as I read them.

How many amps is equal to 1 watt?
For example 12 watts/12 volts = 1 amp.
Converting Amps to Watts.
The conversion of Amps to Watts at fixed voltage is governed by the equation Watts = Amps x Volts.
For example 1 amp * 110 volts = 110 watts.

amperage is something I'm still working on. I noticed this a few days ago about amps (amperage) and have been trying to put it in with volts and watts. amperage might be more of what I need to be focusing on.

 

..... would have to allow for the newer higher wattage stereo inputs .... to reduce the input wattage so the amp could handle it.

When you turn down the volume control on the radio then don't you think it reduces the power going into the Mindblower speaker??

They claimed 10 times the (power) if I read the pic I posted of the ad right. 10X10= 100 watts.

A 40 years old car radio did not produce 10W, it produced maybe 3W or 4W per channel. The Mindblower full power was 30W RMS per channel. If you fed 30W into its input and it survived then its output would be 30W of program plus another 30W of severe distortion.