https://www.amazon.com/dp/B0F5TW8PH7?ref=ppx_yo2ov_dt_b_fed_asin_title
That would be a real bargain for $25.
john larkin <jl@glen--canyon.com> wrote:
<https://www.amazon.com/dp/B0F5TW8PH7?ref=ppx_yo2ov_dt_b_fed_asin_title>
That would be a real bargain for $25.
We optics folk use them all the time.
The circuit versions (mostly YIG-based) work down to nearly DC, like a >gigahertz or something. ;)
https://www.amazon.com/dp/B0F5TW8PH7?ref=ppx_yo2ov_dt_b_fed_asin_title
That would be a real bargain for $25.
On Mon, 28 Jul 2025 12:45:53 -0700, john larkin <jl@glen--canyon.com>
wrote:
https://www.amazon.com/dp/B0F5TW8PH7?ref=ppx_yo2ov_dt_b_fed_asin_title
That would be a real bargain for $25.
It's not really unidirectional. It attenuates -20dB in either
direction. The high power end can handle 10 watts (40dBm) in one
direction. The low power end maybe 20dBm (100 mW) in the opposite
direction. This might be what you mean by "unidirectional".
"Understanding RF Attenuators"
<https://www.youtube.com/watch?v=BpQAoKivS7U>
On Mon, 28 Jul 2025 17:03:15 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:
On Mon, 28 Jul 2025 12:45:53 -0700, john larkin <jl@glen--canyon.com> >>wrote:
https://www.amazon.com/dp/B0F5TW8PH7?ref=ppx_yo2ov_dt_b_fed_asin_title
That would be a real bargain for $25.
It's not really unidirectional. It attenuates -20dB in either
direction. The high power end can handle 10 watts (40dBm) in one >>direction. The low power end maybe 20dBm (100 mW) in the opposite >>direction. This might be what you mean by "unidirectional".
"Understanding RF Attenuators" >><https://www.youtube.com/watch?v=BpQAoKivS7U>
Oh, OK, cheap construction. I'll tell my guys about it. We'll be
testing 700 volt pulses.
On Mon, 28 Jul 2025 19:13:04 -0700, john larkin <jl@glen--canyon.com>
wrote:
On Mon, 28 Jul 2025 17:03:15 -0700, Jeff Liebermann <jeffl@cruzio.com> >>wrote:
On Mon, 28 Jul 2025 12:45:53 -0700, john larkin <jl@glen--canyon.com> >>>wrote:
https://www.amazon.com/dp/B0F5TW8PH7?ref=ppx_yo2ov_dt_b_fed_asin_title
That would be a real bargain for $25.
It's not really unidirectional. It attenuates -20dB in either
direction. The high power end can handle 10 watts (40dBm) in one >>>direction. The low power end maybe 20dBm (100 mW) in the opposite >>>direction. This might be what you mean by "unidirectional".
"Understanding RF Attenuators" >>><https://www.youtube.com/watch?v=BpQAoKivS7U>
Oh, OK, cheap construction. I'll tell my guys about it. We'll be
testing 700 volt pulses.
Ummm... maybe a back of the envelope calculation might be useful to
check if the Amazon attenuator is suitable for your purposes.
The 20dB Amazon RF attenuator is designed to operate at 10 watts into
50 ohms. At 100% duty cycle, 700 V peak into 50 ohms is:
P = E^2 / R = 700^2 / 50 = 9,800 watts
If this is how you are using this RF attenuator at 100% duty cycle,
you might consider having a fire extinguisher handy. Otherwise, I
suggest that you limit your 700 V pulses to:
10 / 9,800 = 0.001
duty cycle. The manufacturers specs probably include a maximum duty
cycle, but I couldn't find anything for the Amazon RF attenuator.
Also, I don't know at what voltage the internal attenuator resistors
will arc over. If you're operating at the rated 10 watts maximum into
50 ohms, the rated maximum voltage would be:
E^2 = P * R
E^2 = 10 watts * 50 ohms
E = sqrt(500) = 22.4 V RMS
If I assume the attenuator might need to handle a 2:1 mismatch, the
impedance will change to 100 ohms:
E^2 = 10 watts * 100 ohms
E = sqrt(1000) = 31.6 V RMS = 44.6 V peak
If that's the highest RMS voltage at which this attenuator was
designed to handle, it might arc over if you apply 700 V peak. I
suggest wearing welding goggles during testing. Fortunately, 44.6 V
is not sufficient to strike an arc, which usually requires 50 to 100
V.
Good luck.
On Mon, 28 Jul 2025 21:05:47 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:
On Mon, 28 Jul 2025 19:13:04 -0700, john larkin <jl@glen--canyon.com> >>wrote:
On Mon, 28 Jul 2025 17:03:15 -0700, Jeff Liebermann <jeffl@cruzio.com> >>>wrote:
On Mon, 28 Jul 2025 12:45:53 -0700, john larkin <jl@glen--canyon.com> >>>>wrote:
That would be a real bargain for $25.https://www.amazon.com/dp/B0F5TW8PH7?ref=ppx_yo2ov_dt_b_fed_asin_title >>>>>
It's not really unidirectional. It attenuates -20dB in either >>>>direction. The high power end can handle 10 watts (40dBm) in one >>>>direction. The low power end maybe 20dBm (100 mW) in the opposite >>>>direction. This might be what you mean by "unidirectional".
"Understanding RF Attenuators" >>>><https://www.youtube.com/watch?v=BpQAoKivS7U>
Oh, OK, cheap construction. I'll tell my guys about it. We'll be
testing 700 volt pulses.
Ummm... maybe a back of the envelope calculation might be useful to
check if the Amazon attenuator is suitable for your purposes.
The 20dB Amazon RF attenuator is designed to operate at 10 watts into
50 ohms. At 100% duty cycle, 700 V peak into 50 ohms is:
P = E^2 / R = 700^2 / 50 = 9,800 watts
If this is how you are using this RF attenuator at 100% duty cycle,
you might consider having a fire extinguisher handy. Otherwise, I
suggest that you limit your 700 V pulses to:
10 / 9,800 = 0.001
duty cycle. The manufacturers specs probably include a maximum duty
cycle, but I couldn't find anything for the Amazon RF attenuator.
Also, I don't know at what voltage the internal attenuator resistors
will arc over. If you're operating at the rated 10 watts maximum into
50 ohms, the rated maximum voltage would be:
E^2 = P * R
E^2 = 10 watts * 50 ohms
E = sqrt(500) = 22.4 V RMS
If I assume the attenuator might need to handle a 2:1 mismatch, the >>impedance will change to 100 ohms:
E^2 = 10 watts * 100 ohms
E = sqrt(1000) = 31.6 V RMS = 44.6 V peak
If that's the highest RMS voltage at which this attenuator was
designed to handle, it might arc over if you apply 700 V peak. I
suggest wearing welding goggles during testing. Fortunately, 44.6 V
is not sufficient to strike an arc, which usually requires 50 to 100
V.
Good luck.
We'll of course keep the pulse widths down, maybe 100 ns, an keep the
duty cycle down too. We're evaluating fast GaN fets as pulse
generators. The Bertan HV bench power supply is only good for 5 mA.
Fortunately the attenuators are cheap and we can afford to blow some
up. They TDR pretty well, plenty good enough for characterizing our
pulsers, GaN fets and txline transformers.
I've just got a couple of interns learning about this stuff. Interns
are cheap and disposable too.
On Mon, 28 Jul 2025 17:03:15 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:
On Mon, 28 Jul 2025 12:45:53 -0700, john larkin <jl@glen--canyon.com>
wrote:
https://www.amazon.com/dp/B0F5TW8PH7?ref=ppx_yo2ov_dt_b_fed_asin_title
That would be a real bargain for $25.
It's not really unidirectional. It attenuates -20dB in either
direction. The high power end can handle 10 watts (40dBm) in one
direction. The low power end maybe 20dBm (100 mW) in the opposite
direction. This might be what you mean by "unidirectional".
"Understanding RF Attenuators"
<https://www.youtube.com/watch?v=BpQAoKivS7U>
Oh, OK, cheap construction. I'll tell my guys about it. We'll be
testing 700 volt pulses.
On Tue, 29 Jul 2025 07:26:06 -0700, john larkin <jl@glen--canyon.com>
wrote:
On Mon, 28 Jul 2025 21:05:47 -0700, Jeff Liebermann <jeffl@cruzio.com> >>wrote:
On Mon, 28 Jul 2025 19:13:04 -0700, john larkin <jl@glen--canyon.com> >>>wrote:
On Mon, 28 Jul 2025 17:03:15 -0700, Jeff Liebermann <jeffl@cruzio.com> >>>>wrote:
On Mon, 28 Jul 2025 12:45:53 -0700, john larkin <jl@glen--canyon.com> >>>>>wrote:
That would be a real bargain for $25.https://www.amazon.com/dp/B0F5TW8PH7?ref=ppx_yo2ov_dt_b_fed_asin_title >>>>>>
It's not really unidirectional. It attenuates -20dB in either >>>>>direction. The high power end can handle 10 watts (40dBm) in one >>>>>direction. The low power end maybe 20dBm (100 mW) in the opposite >>>>>direction. This might be what you mean by "unidirectional".
"Understanding RF Attenuators" >>>>><https://www.youtube.com/watch?v=BpQAoKivS7U>
Oh, OK, cheap construction. I'll tell my guys about it. We'll be >>>>testing 700 volt pulses.
Ummm... maybe a back of the envelope calculation might be useful to
check if the Amazon attenuator is suitable for your purposes.
The 20dB Amazon RF attenuator is designed to operate at 10 watts into
50 ohms. At 100% duty cycle, 700 V peak into 50 ohms is:
P = E^2 / R = 700^2 / 50 = 9,800 watts
If this is how you are using this RF attenuator at 100% duty cycle,
you might consider having a fire extinguisher handy. Otherwise, I >>>suggest that you limit your 700 V pulses to:
10 / 9,800 = 0.001
duty cycle. The manufacturers specs probably include a maximum duty >>>cycle, but I couldn't find anything for the Amazon RF attenuator.
Also, I don't know at what voltage the internal attenuator resistors
will arc over. If you're operating at the rated 10 watts maximum into
50 ohms, the rated maximum voltage would be:
E^2 = P * R
E^2 = 10 watts * 50 ohms
E = sqrt(500) = 22.4 V RMS
If I assume the attenuator might need to handle a 2:1 mismatch, the >>>impedance will change to 100 ohms:
E^2 = 10 watts * 100 ohms
E = sqrt(1000) = 31.6 V RMS = 44.6 V peak
If that's the highest RMS voltage at which this attenuator was
designed to handle, it might arc over if you apply 700 V peak. I
suggest wearing welding goggles during testing. Fortunately, 44.6 V
is not sufficient to strike an arc, which usually requires 50 to 100
V.
Good luck.
We'll of course keep the pulse widths down, maybe 100 ns, an keep the
duty cycle down too. We're evaluating fast GaN fets as pulse
generators. The Bertan HV bench power supply is only good for 5 mA.
Fortunately the attenuators are cheap and we can afford to blow some
up. They TDR pretty well, plenty good enough for characterizing our >>pulsers, GaN fets and txline transformers.
I've just got a couple of interns learning about this stuff. Interns
are cheap and disposable too.
Most of the Amazon power attenuators are horrible, ring like a church
bell.
This one is great.
https://www.amazon.com/dp/B0F5TW8PH7?ref=ppx_yo2ov_dt_b_fed_asin_title
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