PEMF Machines Types - Solid State vs Original Component Technology machines
Comparison of the 2 types:
Original PEMF Types
This is the type that most of the original studies were based off of. These deliver the electric charge no more than 300 nano seconds long. Also over 90% of the that charge was delivered during the first 30 nano second. The original designs were made with spark gap plugs and 99% of the pemf machine except the really expensive ones have this.

This is the best picture I could find without showing a particular manufacturer's internal Pemf components. These have very high maintenance which usually clinics will find there machines get weaker and weaker unless its maintained regularly.

Solid state types do not have this spark gap plug like that the original models have.
Some of the newer companies that are making Pemf machines that are made similar to the original designs are making them too powerful than the spark gap and also the other components can handle. These really powerful machines are very powerful during their warranty period and soon after that, they start deteriorating. This is not cool especially when clinics aren't aware of this scam. I am personally fed up with all the short cuts. I am not going to call each company out but I will recommend the companies that have the least service claims. It all sounds good until a clinic has patients and they have appointments schedules and the clinic has to cancel all the appointment when the machine is sent in for repair.

I urge people if getting the original type to make sure the pemf machine can handle the power and it doesn't have a spark gap that constantly breaks when the machine is cranked up on high for too long.
Solid State PEMF Machines - High price vs. least to zero maintenance
The solid state machines are the latest thing companies are doing since all the issues in the past and maintenance problems. Manufacturers do not like having to pay for their machines sent back and they have to pay shipping both ways and pay to get them fixed.
Solid State PEMF Machines - I avoid high ripple effect - 
Solid state (non spark gap types)
The solid state Pemf generators covert ac to dc voltage current without spark gaps now. The voltage passes through a coil. The ripple effect on the latest Pemf machines are negligible.
Solid State PEMF Machines - How to tell by feel to know it's solid state.
Solid state type without the spark gaps make a rectangular wave for its pulse. The capacitors discharge unlike the spark type. The length of the pulse compared to the time of the entire pulse also gives a solid state Pemf machine its different feel. There is nothing to oxidize during the electrical charge. This type uses a transmission line instead of a spark gap like the earlier models. Transmission line generators are much more expensive when used in a perfect Blumlein configuration. According to the electrical engineer I interviewed, the spark gap plugs are really easy to build and way less expensive than the solid state transmission lines used in the latest models.
Note: A Blumlen generator produces a much briefer pulse and delivers much more energy than any spark gap can produce. The older Pemf generators built with spark gaps change the polarity at such a slower speed that anyone comparing both types instantly can feel the difference.
Note: there are some very good "non solid state" component Pemf machines. If getting an older type, make sure the ripple effect and the "reflection" level is low. The really powerful ones that have a high level feel like a stinging sensation rather than a full pulse.

When 2 outgoing pulses go out and the first pulse is not 100% delivered it can be reflected and this reflection is what weakens the machine.
Solid state machines no matter if the reflection of the charge is not completely unloaded, even if it does come back there is no spark gap to damage. The new solid state type Pemf machines deliver closer to 100% of the pulse without reflection. When on a solid state machine, it is very easy to know from the first pulse.
Another way to tell if you are buying a true solid state Pemf machine. 
So many people are buying machines from companies charging close to the same price as a solid state machine. Usually these are more powerful generators but still are not solid state built. With minimal reflection and ripple effect, the solid state types can pulse faster with more electric joules of energy during each pulse. The rise time is much quicker (how fast the pulse takes to come on). The peak voltage per pulse is also the main difference in the way these types are built. The older type has a much slower rise time. Many people cannot handle a poorly made Pemf machine and get little to no results when the Pemf machine is not delivering enough joules at the right pulse time.
Update: many people are still confused on why they should pay so much more to have solid state components. 
Answer: A long voltage time (early models with low rise times) usually charge the tissues in a way that charges the whole cell membrane, the quick rise times pass "through" the cell.
Note: The older type Pemf machines with the spark gap will still work and I am not here to say they are obsolete. It is just that the new type with its super quick rise can time penetrate deeper instead of just charging up the entire cell membrane. The goal is to not charge the entire cells since this is counteractive as the older slower charging Pemf machines charge cancel out in the cells. Also, the really cheap Pemf machines that deliver high charge but with low rise times can break down the cell membrane.

I have reviewed most of the solid state machines out there from all the companies claiming theirs is the best. I know the real differences and can recommend which solid state machine would be the best fit. Take my Pemf quiz and I will help.

Pemf Consumer Guide
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OMI MAT - E Pulse - BEMER MAT - CURATRON - QRS Mat - Magna Wave Maxx - InfraPemf Pro - MAGNAPULSE - AMPCOIL
...because every company said they had the best PEMF machine

OMI MAT - E Pulse - MAGMAT - CURATRON - QRS Mat - Magna Wave Maxx - InfraPemf Pro - MAGNAPULSE - AMPCOIL - Sentient Element Light
Ask for Sharon
1-877 573-4647

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1-877 573-4647