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Replace DPDT relay with an H-bridge

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Replace DPDT relay with an H-bridge

Postby I_Daniel » Thu Sep 26, 2013 3:11 pm

Dr Bob Beck uses a 555 timer to a transistor which switches the relay on and off. The relay is cross-connected and all the circuit actually does is swap the output from a 27 volt battery source. i.e The battery plus is connected to A and the Minus to B.

When the 555 output goes low the relay drops out and the battery plus is then connected to B and the minus to A
In other words if a motor is connected it will turn forward and then reverse, that is the same function as an H-Bridge.
The H-Bridge I came across has two inputs. a totem pnp/npn transistor configuration on the left and the same circuit on the right.
My question is if I remove the switching transistor and the relay how do I connect, probably using two transistor to replace the 74HC14's (A and B) or direct to the1K resistors, to switch the H-Bridge on and off thus reversing the output. The output load is 30 to 100 micro-amperes so small transistors will do.

Sorry Pete I battle with attachments.

1-2a6d1a3d4c.jpg
1-2a6d1a3d4c.jpg (142.24 KiB) Viewed 6060 times

Bolt_smokeless_Hbridge.gif
Bolt_smokeless_Hbridge.gif (8 KiB) Viewed 6060 times
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Re: Replace DPDT relay with an H-bridge

Postby pebe » Fri Sep 27, 2013 2:20 pm

As your load current is less than 1mA then this circuit should be OK for you.

Tr1 is an inverter that inverts the 555 output so that Tr4 and Tr5 are driven alternately. The bases of Tr2 and Tr3 are fed cross coupled from Tr5 and Tr4 collectors, so that Tr4 switches on Tr3 and Tr5 switches on Tr3.

There could be a brief time during switching when both complementary transistors are on together, but it would only last nanoseconds and the IK resistor, R4 in your circuit, would take care of any current surge.
Attachments
I- Dan 1.GIF
I- Dan 1.GIF (4.18 KiB) Viewed 5993 times
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Re: Replace DPDT relay with an H-bridge

Postby I_Daniel » Fri Sep 27, 2013 5:06 pm

Thank you very much Pebe.

I recently had a malignant growth removed from my scalp. According to research this circuit is something not to scorn as it has been tried and proven since 1992 by Dr Bob Beck and many other researchers. There is also another 30KHz device by Dr Hulda Clark.

Actually Micro Electrical Therapy was a rediscovery of a 19th Century therapy and also from way back to the ancient Egyptians.

This circuit is claimed by Dr Beck and others to also be a cure for HIV, Cancer, Diabetes, Quick healing of bone fractures and a lot of other ailments/viral infections.

I thought I would just mention this as it is an explanation of what this electronic device was designed for.
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