HF amplifier purchase

[Klaus Kragelund]

Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Thanks

Klaus

 

[John Larkin]

On Tue, 3 Mar 2020 15:42:00 -0800 (PST), Klaus Kragelund
<klauskvik@hotmail.com> wrote:

Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Thanks

Klaus

How much current do you need? Can you drive both ends opposite phases?

Some of the THS-series opamps might do it. Maybe use an eval board.

--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

 

[Joerg]

On 2020-03-03 15:42, Klaus Kragelund wrote:

Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

That is usually only the rated load impedance, it's not an internal
resistance. Even though a professor (!) at my university was teaching
that. A modern transistorized ham radio amplifier has a very low output
impedance, a few ohms, but it would (hopefully) go into overload
protection if you load it with less than 50ohms at full power.

Starting at 10kHz would be a challenge, you may have to buy or rent a
real EMI susceptibility test amp for that. 40Vpp ain't much though
unless this has to drive a near-short at lower frequencies. Ham radio
amps start at around 1.5MHz and then go to 30MHz. How much lower they
can go depends on the construction.

--
Regards, Joerg

http://www.analogconsultants.com/

 

[Lasse Langwadt Christense]

onsdag den 4. marts 2020 kl. 00.42.04 UTC+1 skrev Klaus Kragelund:

Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Thanks

Klaus

think this'll work? https://www.analog.com/en/design-center/evaluation-hardware-and-software/evaluation-boards-kits/eval-ada4870.html#eb-overview

 

[Phil Hobbs]

On 2020-03-03 18:42, Klaus Kragelund wrote:

Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Thanks

Klaus

Last time I needed something like that I used an 811A.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[amdx]

On 3/3/2020 7:08 PM, amdx wrote:

On 3/3/2020 5:42 PM, Klaus Kragelund wrote:
Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Thanks

Klaus


 Have you looked at ENI amplifiers, I think most of them are class A.
Probably expensive, here's one, 100watts, 10kHz to 12MHz. 50 ohm output.
   "The 2100L will work into any load impedance. Into a short circuit
or infinite load at some phase angles it may protect itself at power
greater than 80% rated power output. Any power reflected due to output
load mismatch is absorbed in the amplifier. Therefore, although the
output impedance is 50 ohms (maximum VSWR: 2:1), the amplifier will work
into any load impedance."
"Continuous operation into any load or source impedance"

https://www.theemcshop.com/dc-220-mhz-rf-amplifiers/1336-used-ei-eni-2100l-rf-power-amplifier-10-khz-12-mhz-100-watts.html


                                                      Mikek

Sorry, they really love these, $9,400!>
https://www.ebay.com/itm/ENI-E-I-2100L-RF-Power-Amplifier-10-kHz-12-MHz-100-Watts/303262630551?hash=item469bdc8297:g:NdQAAOSwVRpdYGJY

 

[amdx]

On 3/3/2020 5:42 PM, Klaus Kragelund wrote:

Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Thanks

Klaus

Have you looked at ENI amplifiers, I think most of them are class A.
Probably expensive, here's one, 100watts, 10kHz to 12MHz. 50 ohm output.
"The 2100L will work into any load impedance. Into a short circuit
or infinite load at some phase angles it may protect itself at power
greater than 80% rated power output. Any power reflected due to output
load mismatch is absorbed in the amplifier. Therefore, although the
output impedance is 50 ohms (maximum VSWR: 2:1), the amplifier will work
into any load impedance."
"Continuous operation into any load or source impedance"

> https://www.theemcshop.com/dc-220-mhz-rf-amplifiers/1336-used-ei-eni-2100l-rf-power-amplifier-10-khz-12-mhz-100-watts.html

Mikek

 

On Tue, 3 Mar 2020 15:42:00 -0800 (PST), Klaus Kragelund
<klauskvik@hotmail.com> wrote:

Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

40 Vpp is 14 Vrms

>Tried to find gear that would do that, but they all have 50 ohms output

To drive 14Vrms into 50 ohms requires 4 W power or 0.3 Arms current.

A small HF amplifier could easily deliver that, but the problem is the
required large frequency range 1:2000, so the question is how well the
internal transmission line transformers will handle this frequency
range. At least the internal transmission line transformer ferrite
material may have to be changed.

>Anyone got a link for a amplifier that can do this?

Some 1:4 or 1:9 external transmission transformers could use to feed
also loads of 5.5. 12.5, 200 or 450 ohms.

 

[Klaus Kragelund]

On Wednesday, March 4, 2020 at 2:08:26 AM UTC+1, amdx wrote:

On 3/3/2020 5:42 PM, Klaus Kragelund wrote:
Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Thanks

Klaus


Have you looked at ENI amplifiers, I think most of them are class A.
Probably expensive, here's one, 100watts, 10kHz to 12MHz. 50 ohm output.
"The 2100L will work into any load impedance. Into a short circuit
or infinite load at some phase angles it may protect itself at power
greater than 80% rated power output. Any power reflected due to output
load mismatch is absorbed in the amplifier. Therefore, although the
output impedance is 50 ohms (maximum VSWR: 2:1), the amplifier will work
into any load impedance."
"Continuous operation into any load or source impedance"

https://www.theemcshop.com/dc-220-mhz-rf-amplifiers/1336-used-ei-eni-2100l-rf-power-amplifier-10-khz-12-mhz-100-watts.html

Mikek

That is a nice selection of power HF amps

I would like something with 0 ohms output, but if I am sure I will not short it, I could just open it and short the 50 ohms resistor

Cheers

Klaus

 

[Klaus Kragelund]

On Wednesday, March 4, 2020 at 1:57:09 AM UTC+1, Phil Hobbs wrote:

On 2020-03-03 18:42, Klaus Kragelund wrote:
Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Thanks

Klaus


Last time I needed something like that I used an 811A.

I use the HP 33120A, which has more or less the same specs, 20V into 50ohms, but that limits the power drive, and when driving square wave signals it gets distorted

Cheers

Klaus

 

[Klaus Kragelund]

On Wednesday, March 4, 2020 at 12:59:22 AM UTC+1, Lasse Langwadt Christensen wrote:

onsdag den 4. marts 2020 kl. 00.42.04 UTC+1 skrev Klaus Kragelund:
Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Thanks

Klaus

think this'll work? https://www.analog.com/en/design-center/evaluation-hardware-and-software/evaluation-boards-kits/eval-ada4870.html#eb-overview

Yes, this could work for sure

 

[Klaus Kragelund]

On Wednesday, March 4, 2020 at 12:57:56 AM UTC+1, John Larkin wrote:

On Tue, 3 Mar 2020 15:42:00 -0800 (PST), Klaus Kragelund
klauskvik@hotmail.com> wrote:

Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Thanks

Klaus

How much current do you need? Can you drive both ends opposite phases?

Some of the THS-series opamps might do it. Maybe use an eval board.

I would like to have an instrument, so I do not need to spend time on setup etc.

But, I had the same trail of thought, so I ordered this one as a backup solution:

https://dk.farnell.com/texas-instruments/ths4031evm/evaluation-module-amplifier/dp/3125639?CMP=i-bf9f-00001000

Cheers

Klaus

 

[Tauno Voipio]

On 4.3.20 08:44, upsidedown@downunder.com wrote:

On Tue, 3 Mar 2020 15:42:00 -0800 (PST), Klaus Kragelund
klauskvik@hotmail.com> wrote:

Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

40 Vpp is 14 Vrms

Tried to find gear that would do that, but they all have 50 ohms output

To drive 14Vrms into 50 ohms requires 4 W power or 0.3 Arms current.

A small HF amplifier could easily deliver that, but the problem is the
required large frequency range 1:2000, so the question is how well the
internal transmission line transformers will handle this frequency
range. At least the internal transmission line transformer ferrite
material may have to be changed.

Anyone got a link for a amplifier that can do this?

Some 1:4 or 1:9 external transmission transformers could use to feed
also loads of 5.5. 12.5, 200 or 450 ohms.

The problem lies with the low end of the frequency range, effectively
preventing the use of wideband transformers. Uncontrolled load impedance
is something a RF amplifier is not happy with, it makes it necessary
to make a far too large amplifier to cope with the surprising loads.

--

-TV

 

[Gerhard Hoffmann]

Am 04.03.20 um 00:42 schrieb Klaus Kragelund:

Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Sounds like a job for a HP3325B fun generator with
high voltage option.

Everybody should have one.

regards, Gerhard

 

[Michael Terrell]

On Wednesday, March 4, 2020 at 5:45:43 AM UTC-5, Gerhard Hoffmann wrote:

Am 04.03.20 um 00:42 schrieb Klaus Kragelund:
Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Sounds like a job for a HP3325B fun generator with
high voltage option.

Everybody should have one.

regards, Gerhard

Option 002 is also available on the 3325A version. Both use the A8 - High Voltage Output Assembly - 03325-66508

Beware that many of these have been removed from used generators before they are resold. Two of my 3325A arrived minus that board.

 

On Tue, 3 Mar 2020 22:47:27 -0800 (PST), Klaus Kragelund
<klauskvik@hotmail.com> wrote:

On Wednesday, March 4, 2020 at 12:57:56 AM UTC+1, John Larkin wrote:
On Tue, 3 Mar 2020 15:42:00 -0800 (PST), Klaus Kragelund
klauskvik@hotmail.com> wrote:

Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Thanks

Klaus

How much current do you need? Can you drive both ends opposite phases?

Some of the THS-series opamps might do it. Maybe use an eval board.


I would like to have an instrument, so I do not need to spend time on setup etc.

But, I had the same trail of thought, so I ordered this one as a backup solution:

https://dk.farnell.com/texas-instruments/ths4031evm/evaluation-module-amplifier/dp/3125639?CMP=i-bf9f-00001000

Cheers

Klaus

THS6022 is a beast.



--

John Larkin Highland Technology, Inc

The cork popped merrily, and Lord Peter rose to his feet.
"Bunter", he said, "I give you a toast. The triumph of Instinct over Reason"

 

On Wed, 4 Mar 2020 08:19:58 -0800 (PST), George Herold
<ggherold@gmail.com> wrote:

On Wednesday, March 4, 2020 at 10:09:52 AM UTC-5, jla...@highlandsniptechnology.com wrote:
On Tue, 3 Mar 2020 22:47:27 -0800 (PST), Klaus Kragelund
klauskvik@hotmail.com> wrote:

On Wednesday, March 4, 2020 at 12:57:56 AM UTC+1, John Larkin wrote:
On Tue, 3 Mar 2020 15:42:00 -0800 (PST), Klaus Kragelund
klauskvik@hotmail.com> wrote:

Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Thanks

Klaus

How much current do you need? Can you drive both ends opposite phases?

Some of the THS-series opamps might do it. Maybe use an eval board.


I would like to have an instrument, so I do not need to spend time on setup etc.

But, I had the same trail of thought, so I ordered this one as a backup solution:

https://dk.farnell.com/texas-instruments/ths4031evm/evaluation-module-amplifier/dp/3125639?CMP=i-bf9f-00001000

Cheers

Klaus

THS6022 is a beast.

There are nice tables in AoE-X, but they don't have those line drivers.

Klaus, the THS4031 has only 100 V/us slew rate. Is that going to work?

George H.

Never use THS3062.



--

John Larkin Highland Technology, Inc

The cork popped merrily, and Lord Peter rose to his feet.
"Bunter", he said, "I give you a toast. The triumph of Instinct over Reason"

 

[George Herold]

On Wednesday, March 4, 2020 at 10:09:52 AM UTC-5, jla...@highlandsniptechnology.com wrote:

On Tue, 3 Mar 2020 22:47:27 -0800 (PST), Klaus Kragelund
klauskvik@hotmail.com> wrote:

On Wednesday, March 4, 2020 at 12:57:56 AM UTC+1, John Larkin wrote:
On Tue, 3 Mar 2020 15:42:00 -0800 (PST), Klaus Kragelund
klauskvik@hotmail.com> wrote:

Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Thanks

Klaus

How much current do you need? Can you drive both ends opposite phases?

Some of the THS-series opamps might do it. Maybe use an eval board.


I would like to have an instrument, so I do not need to spend time on setup etc.

But, I had the same trail of thought, so I ordered this one as a backup solution:

https://dk.farnell.com/texas-instruments/ths4031evm/evaluation-module-amplifier/dp/3125639?CMP=i-bf9f-00001000

Cheers

Klaus

THS6022 is a beast.

There are nice tables in AoE-X, but they don't have those line drivers.

Klaus, the THS4031 has only 100 V/us slew rate. Is that going to work?

George H.

--

John Larkin Highland Technology, Inc

The cork popped merrily, and Lord Peter rose to his feet.
"Bunter", he said, "I give you a toast. The triumph of Instinct over Reason"

 

[George Herold]

On Wednesday, March 4, 2020 at 11:31:06 AM UTC-5, jla...@highlandsniptechnology.com wrote:

On Wed, 4 Mar 2020 08:19:58 -0800 (PST), George Herold
ggherold@gmail.com> wrote:

On Wednesday, March 4, 2020 at 10:09:52 AM UTC-5, jla...@highlandsniptechnology.com wrote:
On Tue, 3 Mar 2020 22:47:27 -0800 (PST), Klaus Kragelund
klauskvik@hotmail.com> wrote:

On Wednesday, March 4, 2020 at 12:57:56 AM UTC+1, John Larkin wrote:
On Tue, 3 Mar 2020 15:42:00 -0800 (PST), Klaus Kragelund
klauskvik@hotmail.com> wrote:

Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Thanks

Klaus

How much current do you need? Can you drive both ends opposite phases?

Some of the THS-series opamps might do it. Maybe use an eval board.


I would like to have an instrument, so I do not need to spend time on setup etc.

But, I had the same trail of thought, so I ordered this one as a backup solution:

https://dk.farnell.com/texas-instruments/ths4031evm/evaluation-module-amplifier/dp/3125639?CMP=i-bf9f-00001000

Cheers

Klaus

THS6022 is a beast.

There are nice tables in AoE-X, but they don't have those line drivers.

Klaus, the THS4031 has only 100 V/us slew rate. Is that going to work?

George H.

Never use THS3062.

The ADA4870 from Lasse looks like a beast!
(Did ya see the size of that thermal pad?)

Oh... I list of opamaps not to use and why would be good.

The opa124 has a voltage noise hump ~20 kHz or so... it's been too long.

George H.

--

John Larkin Highland Technology, Inc

The cork popped merrily, and Lord Peter rose to his feet.
"Bunter", he said, "I give you a toast. The triumph of Instinct over Reason"

 

[LM]

On Wed, 04 Mar 2020 07:09:43 -0800, jlarkin@highlandsniptechnology.com
wrote:

On Tue, 3 Mar 2020 22:47:27 -0800 (PST), Klaus Kragelund
klauskvik@hotmail.com> wrote:

On Wednesday, March 4, 2020 at 12:57:56 AM UTC+1, John Larkin wrote:
On Tue, 3 Mar 2020 15:42:00 -0800 (PST), Klaus Kragelund
klauskvik@hotmail.com> wrote:

Hi

I need to drive a coil with 40Vpp at 10kHz to 20MHz for a test

Tried to find gear that would do that, but they all have 50 ohms output

Anyone got a link for a amplifier that can do this?

Thanks

Klaus

How much current do you need? Can you drive both ends opposite phases?

Some of the THS-series opamps might do it. Maybe use an eval board.


I would like to have an instrument, so I do not need to spend time on setup etc.

But, I had the same trail of thought, so I ordered this one as a backup solution:

https://dk.farnell.com/texas-instruments/ths4031evm/evaluation-module-amplifier/dp/3125639?CMP=i-bf9f-00001000

Cheers

Klaus

THS6022 is a beast.
Digikey has problems. It finds something else with that name.