Around $500. It will only take some tens of mA across the secondary.
For most applications, the transformer is inserted between the voltage sense network and the error amplifier (which is high impedance.)
Hello Jack in NJ,
For this post I ask forgiveness, also looking for permission for next time.
The next little bench project will be to assemble an injection transformer to examine PSRR of amplifiers and power supplies; this may stretch the limits of the conversation a bit beyond network analyzers.
See the attached photo of a Jensen Transformer and assorted parts, pieces and a Hammond plastic project box. This transformer came by way of your recommendation along with Technical Note TN106 over at AP.com .
A next step will be a simple power supply that includes a ~5Ohm injection resistor in the error amplifier loop. I will try the diy injection transformer. I also have the use of a Omicron Lab B-Wit 100 transformer to run through the motions.
Thanks DT
For this post I ask forgiveness, also looking for permission for next time.
The next little bench project will be to assemble an injection transformer to examine PSRR of amplifiers and power supplies; this may stretch the limits of the conversation a bit beyond network analyzers.
See the attached photo of a Jensen Transformer and assorted parts, pieces and a Hammond plastic project box. This transformer came by way of your recommendation along with Technical Note TN106 over at AP.com .
A next step will be a simple power supply that includes a ~5Ohm injection resistor in the error amplifier loop. I will try the diy injection transformer. I also have the use of a Omicron Lab B-Wit 100 transformer to run through the motions.
Thanks DT
Attachments
Hello,
Don’t worry about the 2X4 my favorite bludgeon is a hickory pick handle.
Why not the $179 Analog Discovery.
First I have out lived all my beneficiaries.
I started out on the National Instrument DAQ/PXI path. Originally there was National Instrument ELVIS, the older brother to Analog Discovery. On the bench there still is a functioning PXI main frame with 4071 7 ½ digit DMM and a 4461 24bit sound / vibration cards installed; there are enough switching relays to program a railroad. All this NI LabView stuff quickly became an expensive addiction. Analog Discovery and the student version of LabView come cheap. The annual subscription to the NI audio software costs more than the Bode-100. Analog Discovery connects National Instruments to a student’s computer for life. If it works for you make the connection.
I like the Bode-100 because it is priced relatively inexpensive for the 40-50Mhz performance point. That 40-50Mhz point targets the PDN market.
Go over to Keysight or any of the big players and you notice that they all use and reference PicoTest current injectors, injection transformers, low noise amplifiers whatever. PicoTest owns all of that PDN measurement stuff.
PicoTest is owned and marketed by the same Guy as Omicron Labs. Speaking of marketing they publish many white papers and books demonstrating their stuff. They also offer training around the world.
Not so much National Instruments Analog Discovery.
Your mileage may vary.
Thanks
DT
https://benthamopen.com/contents/pdf/TOOPTSJ/TOOPTSJ-5-51.pdf
Don’t worry about the 2X4 my favorite bludgeon is a hickory pick handle.
Why not the $179 Analog Discovery.
First I have out lived all my beneficiaries.
I started out on the National Instrument DAQ/PXI path. Originally there was National Instrument ELVIS, the older brother to Analog Discovery. On the bench there still is a functioning PXI main frame with 4071 7 ½ digit DMM and a 4461 24bit sound / vibration cards installed; there are enough switching relays to program a railroad. All this NI LabView stuff quickly became an expensive addiction. Analog Discovery and the student version of LabView come cheap. The annual subscription to the NI audio software costs more than the Bode-100. Analog Discovery connects National Instruments to a student’s computer for life. If it works for you make the connection.
I like the Bode-100 because it is priced relatively inexpensive for the 40-50Mhz performance point. That 40-50Mhz point targets the PDN market.
Go over to Keysight or any of the big players and you notice that they all use and reference PicoTest current injectors, injection transformers, low noise amplifiers whatever. PicoTest owns all of that PDN measurement stuff.
PicoTest is owned and marketed by the same Guy as Omicron Labs. Speaking of marketing they publish many white papers and books demonstrating their stuff. They also offer training around the world.
Not so much National Instruments Analog Discovery.
Your mileage may vary.
Thanks
DT
https://benthamopen.com/contents/pdf/TOOPTSJ/TOOPTSJ-5-51.pdf
Last edited:
DIY Variant
Hello Jack and All,
Back from 10 days off the grid. Jack thank you for posting the Bode 100 videos. While I was gone I received some parts. From Mouser and Apexjr.com . The second video shows the inside of the B-Wit Injection transformer. (near 2:30 from the beginning).
I am guessing that the toroid core is a high permeability VAC 500 core see the link below for the part purchased. The photo shows a black Hammond diecast enclosure. The one I will use is red, see the link below.
I like all the bright colors, the Teflon insulated silver plated solid core 22AWG wire is from ApexJr.com . I plan to twist the conductors together with a drill motor. Then wrap the twisted pair onto the core.
The Bode 100 will be handy to test both the real B-100 and my DIY Variant.
Thanks DT
https://www.mouser.com/datasheet/2/599/W514-238036.pdf
https://www.mouser.com/datasheet/2/177/1590B-68774.pdf[/FONT]
Hello Jack and All,
Back from 10 days off the grid. Jack thank you for posting the Bode 100 videos. While I was gone I received some parts. From Mouser and Apexjr.com . The second video shows the inside of the B-Wit Injection transformer. (near 2:30 from the beginning).
I am guessing that the toroid core is a high permeability VAC 500 core see the link below for the part purchased. The photo shows a black Hammond diecast enclosure. The one I will use is red, see the link below.
I like all the bright colors, the Teflon insulated silver plated solid core 22AWG wire is from ApexJr.com . I plan to twist the conductors together with a drill motor. Then wrap the twisted pair onto the core.
The Bode 100 will be handy to test both the real B-100 and my DIY Variant.
Thanks DT
https://www.mouser.com/datasheet/2/599/W514-238036.pdf
https://www.mouser.com/datasheet/2/177/1590B-68774.pdf[/FONT]
Attachments
Hello Jack in New Jersey,
I share the idea that the Bode100 will work well to test these high tech torid VAC cores.
Please share your ideas about measuring high voltage and not letting the smoke out of the VNA.
Reading by flashlight in Steve Sandler’s book “Power Integrity” Chapter 8 on Measuring Stability, page 161, figure 8.11, Steve shows using an op-amp to buffer a voltage divider then measuring at the output of the op-amp. This is on my list of possibles for measuring tube amp high voltage power supplies.
DT
Cores - VACUUMSCHMELZE GmbH & Co. KG
I share the idea that the Bode100 will work well to test these high tech torid VAC cores.
Please share your ideas about measuring high voltage and not letting the smoke out of the VNA.
Reading by flashlight in Steve Sandler’s book “Power Integrity” Chapter 8 on Measuring Stability, page 161, figure 8.11, Steve shows using an op-amp to buffer a voltage divider then measuring at the output of the op-amp. This is on my list of possibles for measuring tube amp high voltage power supplies.
DT
Cores - VACUUMSCHMELZE GmbH & Co. KG
Last edited:
Hello,
My post was targeted at a voltage divider and op-amp buffer used to sample/measure a high voltage point in a PDN, not so much just stability.
Perhaps think of the voltage divider and op-amp as an active probe used to sample; noise, stability, PSRR, Reverse PSRR or any of the variables measured in a power supply.
Just thinking and sharing out loud.
West Coast Time
DT
My post was targeted at a voltage divider and op-amp buffer used to sample/measure a high voltage point in a PDN, not so much just stability.
Perhaps think of the voltage divider and op-amp as an active probe used to sample; noise, stability, PSRR, Reverse PSRR or any of the variables measured in a power supply.
Just thinking and sharing out loud.
West Coast Time
DT
Photovoltaic isolators
Jack,
Please share a bit more.
I have spent some time in an effort to sort this photovoltaic isolator thing out. Excellent voltage isolation.
Looks like photovoltaic isolators are more related to switches than linear input to output devices. Photovoltaic isolators have finite turn on and even longer turn off times, better suited to switching than variable frequency input/output sweeps. This is my impression from reading several application notes.
Have you built one of these?
Thanks DT
Jack,
Please share a bit more.
I have spent some time in an effort to sort this photovoltaic isolator thing out. Excellent voltage isolation.
Looks like photovoltaic isolators are more related to switches than linear input to output devices. Photovoltaic isolators have finite turn on and even longer turn off times, better suited to switching than variable frequency input/output sweeps. This is my impression from reading several application notes.
Have you built one of these?
Thanks DT
Bode 100 xfmr reverse engineering EEVblog #1104 - Omicron Labs Bode 100 Teardown - Page 1 maybe helpful, more can be found there
for linear optoisolation HCNR200
the part is actually multisourced as IL300 LOC110
for linear optoisolation HCNR200
the part is actually multisourced as IL300 LOC110
Hello Jack,
Thank you for sharing your progress.
Is it a IFR840 MOSFET?
Is it a VO1263A?
Is it a Picotest J2120A Line Injector driving the gate of a IFR840 MOSFET?
Thanks DT
Thank you for sharing your progress.
What is it that you are speaking about?
Is it a IFR840 MOSFET?
Is it a VO1263A?
Is it a Picotest J2120A Line Injector driving the gate of a IFR840 MOSFET?
Thanks DT
Home Roll
Hello,
This https://www.mouser.com/datasheet/2/599/W514-238036.pdf core looks to be the exact core used in the B-Wit injection transformer.
With 40 turns of CAT 6 plenum twisted pair conductors the VAC T60006-L2030-W514-03- tests 99 + % identical to the B-WIT injection transformer.
See the attached plots.
1) B-WIT plot
2) Home Roll using the core noted above.
Thanks DT
Hello,
This https://www.mouser.com/datasheet/2/599/W514-238036.pdf core looks to be the exact core used in the B-Wit injection transformer.
With 40 turns of CAT 6 plenum twisted pair conductors the VAC T60006-L2030-W514-03- tests 99 + % identical to the B-WIT injection transformer.
See the attached plots.
1) B-WIT plot
2) Home Roll using the core noted above.
Thanks DT
Attachments
- Status
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