ELF HV amplification techniques?

[Bob Martin]

I need to amplify to 2 KV complex waveforms (not pulses) in the 1-20
Hz range. Only a few milliamps are required for maintanence of an
electrostatic field.

As far as I can determine, there are three options.

1. A high voltage output transisitor from a TV. These are available up
to 5KV.

2. More commonly available lower voltage transistors and components
in a "ladder" configuration.

3. Step-up transformer wound on a special core.

The first two options have the disadvantage of requiring a HV power
supply.

The transformer, on the other hand, would be expensive unless there is
an off-the-shelf option. Size and distortion might be other detracting
features.

Can anyone advise regarding best practice for this application and
where a circuit may be found?

Bob Martin

 

[John Larkin]

I need to amplify to 2 KV complex waveforms (not pulses) in the 1-20
Hz range. Only a few milliamps are required for maintanence of an
electrostatic field.

If it's just an electrostatic field, microamps should be plenty.

As far as I can determine, there are three options.

1. A high voltage output transisitor from a TV. These are available up
to 5KV.

Really? Where? 2KV is the highest I've seen.

2. More commonly available lower voltage transistors and components
in a "ladder" configuration.

3. Step-up transformer wound on a special core.

4. Use a tube.

John

 

[Scott Stephens]

I need to amplify to 2 KV complex waveforms (not pulses) in the 1-20
Hz range. Only a few milliamps are required for maintanence of an
electrostatic field.

As far as I can determine, there are three options.

There are more. You could pulse-width modulate a several kilohertz
carrier with the ELF and drive a monitor flyback transformer, then use
high-voltage rectifier and low-pass filter the HV.



--
Scott

**********************************

DIY Piezo-Gyro, PCB Drill Bot & More Soon!

http://home.comcast.net/~scottxs/

**********************************

 

[GPG]

Bob Martin wrote:

Thre are plenty of 12 B&W transformers for small TVs out there.
12V HT, drive properly and modulate the 12V ht
BTW, 2SD838 , 2.5 KV is as high as i have come across, used
in Sanyo TVs some time ago

 

[Tim Shoppa]

I need to amplify to 2 KV complex waveforms (not pulses) in the 1-20
Hz range. Only a few milliamps are required for maintanence of an
electrostatic field.

As far as I can determine, there are three options.

1. A high voltage output transisitor from a TV. These are available up
to 5KV.

2. More commonly available lower voltage transistors and components
in a "ladder" configuration.

3. Step-up transformer wound on a special core.

The first two options have the disadvantage of requiring a HV power
supply.

The transformer, on the other hand, would be expensive unless there is
an off-the-shelf option. Size and distortion might be other detracting
features.

Can anyone advise regarding best practice for this application and
where a circuit may be found?

There are programmable power supplies in that range already, commonly
used in high energy/nuclear physics for detector supplies. Interfaces
I've seen used are GPIB, CAMAC, and raw TTL. See for example

http://www.emcohighvoltage.com/PMTSelectionGuide.htm

http://www.canberra.com/products/658.asp

Tim.

 

[Winfield Hill]

Bob Martin wrote...

I need to amplify to 2 KV complex waveforms (not pulses) in the
1-20 Hz range. Only a few milliamps are required for maintanence
of an electrostatic field.

As far as I can determine, there are three options. [ snip ]

None of those options look advisable to me. If amplify means
to create an identical waveform, but larger in amplitude, then
you need an accurate high-voltage amplifier. There are several
companies that make these, such as Trek. I've also posted some
info about my HV amp designs for advanced users here on s.e.d.
But be careful, high-voltage circuits are dangerous. Also once
you get over 1200V rail-to-rail, protected series connections
are required for each element, and the going gets much tougher.

Thanks,
- Win

whill_at_picovolt-dot-com

 

[George R. Gonzalez]

A couple ideas:

Use a flyback transformer from a TV set.

Use one of those high-voltage tubes used as series-regulators in old TV
sets. The 6BK4 comes to mind.

There's also the battleship-like 715-ABC tube, good for 60 watts, 10 amps
peak.