signal indicator

[John Larkin]

On Thu, 02 May 2019 20:15:21 -0700, John Larkin
<jjlarkin@highlandtechnology.com> wrote:

I'll have a LVDS signal with data or a square wave, in the range of
maybe 1 MHz to 2 GHz. I figure I can pump it through an 10EP89 ECL
buffer to give it some heft. Each output will become almost 2 volts
p-p.

I'd like to light an LED if there is signal present. How does this
look?

https://www.dropbox.com/s/bvyjs4zgyprx3tu/Sig_Indicator.JPG?dl=0

The 10 pF caps shouldn't load my signals much, especially in the lower
signal path that doesn't need to be super fast.

I suppose I could buy some fancy RF detector chip, but I'd rather just
use fairly ordinary parts.

Any other ideas?

Looks like I might have an unused CML differential output from a logic
fanout chip. Here's a detector that drives a single schottky diode
differentially.

https://www.dropbox.com/s/7zo9kmiuhs532ww/CML_SD2.jpg?dl=0

That sweep is from 0 to 5 GHz.

I'm using the CML gate outputs unterminated, which I think puts -16 mA
alternately into its internal 50 ohm resistors, 800 mV p-p at each
pin.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[Jan Panteltje]

On a sunny day (Tue, 07 May 2019 20:21:13 -0700) it happened John Larkin
<jjlarkin@highlandtechnology.com> wrote in
<c9i4de5apteq5en9qggebr22qgqn6t31hr@4ax.com>:

On Thu, 02 May 2019 20:15:21 -0700, John Larkin
jjlarkin@highlandtechnology.com> wrote:


I'll have a LVDS signal with data or a square wave, in the range of
maybe 1 MHz to 2 GHz. I figure I can pump it through an 10EP89 ECL
buffer to give it some heft. Each output will become almost 2 volts
p-p.

I'd like to light an LED if there is signal present. How does this
look?

https://www.dropbox.com/s/bvyjs4zgyprx3tu/Sig_Indicator.JPG?dl=0

The 10 pF caps shouldn't load my signals much, especially in the lower
signal path that doesn't need to be super fast.

I suppose I could buy some fancy RF detector chip, but I'd rather just
use fairly ordinary parts.

Any other ideas?

Looks like I might have an unused CML differential output from a logic
fanout chip. Here's a detector that drives a single schottky diode
differentially.

https://www.dropbox.com/s/7zo9kmiuhs532ww/CML_SD2.jpg?dl=0

That sweep is from 0 to 5 GHz.

I'm using the CML gate outputs unterminated, which I think puts -16 mA
alternately into its internal 50 ohm resistors, 800 mV p-p at each
pin.

Would this work? BAT15-099 0.35 pF 12 GHz 5.5 Ohm forward ~.3 V
http://panteltje.com/pub/detector_IMG_6900.JPG

 

[John Larkin]

On Wed, 08 May 2019 07:41:32 GMT, Jan Panteltje
<pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Tue, 07 May 2019 20:21:13 -0700) it happened John Larkin
jjlarkin@highlandtechnology.com> wrote in
c9i4de5apteq5en9qggebr22qgqn6t31hr@4ax.com>:

On Thu, 02 May 2019 20:15:21 -0700, John Larkin
jjlarkin@highlandtechnology.com> wrote:


I'll have a LVDS signal with data or a square wave, in the range of
maybe 1 MHz to 2 GHz. I figure I can pump it through an 10EP89 ECL
buffer to give it some heft. Each output will become almost 2 volts
p-p.

I'd like to light an LED if there is signal present. How does this
look?

https://www.dropbox.com/s/bvyjs4zgyprx3tu/Sig_Indicator.JPG?dl=0

The 10 pF caps shouldn't load my signals much, especially in the lower
signal path that doesn't need to be super fast.

I suppose I could buy some fancy RF detector chip, but I'd rather just
use fairly ordinary parts.

Any other ideas?

Looks like I might have an unused CML differential output from a logic
fanout chip. Here's a detector that drives a single schottky diode
differentially.

https://www.dropbox.com/s/7zo9kmiuhs532ww/CML_SD2.jpg?dl=0

That sweep is from 0 to 5 GHz.

I'm using the CML gate outputs unterminated, which I think puts -16 mA
alternately into its internal 50 ohm resistors, 800 mV p-p at each
pin.

Would this work? BAT15-099 0.35 pF 12 GHz 5.5 Ohm forward ~.3 V
http://panteltje.com/pub/detector_IMG_6900.JPG

Yes, that works. I might be wrong about the CML swing (gotta verify
that) which is officially 400 mv p-p at each pin when externally
terminated. I'm not terminating so I expect 0.8 p-p. The 2-diode
voltage doubler would be a little wimpy if each one only sees 0.4 p-p.

My 1-diode thing works usably at 0.4 p-p.

How fast can one do a Cockcroft–Walton multiplier?


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[Jan Panteltje]

On a sunny day (Wed, 08 May 2019 07:21:47 -0700) it happened John Larkin
<jjlarkin@highlandtechnology.com> wrote in
<l5p5de9rj05hvl8a4rhd1hkem929vmplf0@4ax.com>:

On Wed, 08 May 2019 07:41:32 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Tue, 07 May 2019 20:21:13 -0700) it happened John Larkin
jjlarkin@highlandtechnology.com> wrote in
c9i4de5apteq5en9qggebr22qgqn6t31hr@4ax.com>:

On Thu, 02 May 2019 20:15:21 -0700, John Larkin
jjlarkin@highlandtechnology.com> wrote:


I'll have a LVDS signal with data or a square wave, in the range of
maybe 1 MHz to 2 GHz. I figure I can pump it through an 10EP89 ECL
buffer to give it some heft. Each output will become almost 2 volts
p-p.

I'd like to light an LED if there is signal present. How does this
look?

https://www.dropbox.com/s/bvyjs4zgyprx3tu/Sig_Indicator.JPG?dl=0

The 10 pF caps shouldn't load my signals much, especially in the lower
signal path that doesn't need to be super fast.

I suppose I could buy some fancy RF detector chip, but I'd rather just
use fairly ordinary parts.

Any other ideas?

Looks like I might have an unused CML differential output from a logic
fanout chip. Here's a detector that drives a single schottky diode
differentially.

https://www.dropbox.com/s/7zo9kmiuhs532ww/CML_SD2.jpg?dl=0

That sweep is from 0 to 5 GHz.

I'm using the CML gate outputs unterminated, which I think puts -16 mA
alternately into its internal 50 ohm resistors, 800 mV p-p at each
pin.

Would this work? BAT15-099 0.35 pF 12 GHz 5.5 Ohm forward ~.3 V
http://panteltje.com/pub/detector_IMG_6900.JPG

Yes, that works. I might be wrong about the CML swing (gotta verify
that) which is officially 400 mv p-p at each pin when externally
terminated. I'm not terminating so I expect 0.8 p-p. The 2-diode
voltage doubler would be a little wimpy if each one only sees 0.4 p-p.

My 1-diode thing works usably at 0.4 p-p.

How fast can one do a Cockcroft–Walton multiplier?

Never tried that above 40 kHz or so, but why not.
But it only takes .7 V to open a NPN, 150 mV for a Ge.
And you can bias the detector - side to reduce that.

 

[Jan Panteltje]

On a sunny day (Wed, 08 May 2019 09:48:00 -0700) it happened John Larkin
<jjlarkin@highlandtechnology.com> wrote in
<3t16de5pdfm9qnki9a1sqal1n0lomp5v5v@4ax.com>:

On Wed, 08 May 2019 16:06:46 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Wed, 08 May 2019 07:21:47 -0700) it happened John Larkin
jjlarkin@highlandtechnology.com> wrote in
l5p5de9rj05hvl8a4rhd1hkem929vmplf0@4ax.com>:

On Wed, 08 May 2019 07:41:32 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Tue, 07 May 2019 20:21:13 -0700) it happened John Larkin
jjlarkin@highlandtechnology.com> wrote in
c9i4de5apteq5en9qggebr22qgqn6t31hr@4ax.com>:

On Thu, 02 May 2019 20:15:21 -0700, John Larkin
jjlarkin@highlandtechnology.com> wrote:


I'll have a LVDS signal with data or a square wave, in the range of
maybe 1 MHz to 2 GHz. I figure I can pump it through an 10EP89 ECL
buffer to give it some heft. Each output will become almost 2 volts
p-p.

I'd like to light an LED if there is signal present. How does this
look?

https://www.dropbox.com/s/bvyjs4zgyprx3tu/Sig_Indicator.JPG?dl=0

The 10 pF caps shouldn't load my signals much, especially in the lower
signal path that doesn't need to be super fast.

I suppose I could buy some fancy RF detector chip, but I'd rather just
use fairly ordinary parts.

Any other ideas?

Looks like I might have an unused CML differential output from a logic
fanout chip. Here's a detector that drives a single schottky diode
differentially.

https://www.dropbox.com/s/7zo9kmiuhs532ww/CML_SD2.jpg?dl=0

That sweep is from 0 to 5 GHz.

I'm using the CML gate outputs unterminated, which I think puts -16 mA
alternately into its internal 50 ohm resistors, 800 mV p-p at each
pin.

Would this work? BAT15-099 0.35 pF 12 GHz 5.5 Ohm forward ~.3 V
http://panteltje.com/pub/detector_IMG_6900.JPG

Yes, that works. I might be wrong about the CML swing (gotta verify
that) which is officially 400 mv p-p at each pin when externally
terminated. I'm not terminating so I expect 0.8 p-p. The 2-diode
voltage doubler would be a little wimpy if each one only sees 0.4 p-p.

My 1-diode thing works usably at 0.4 p-p.

How fast can one do a Cockcroft–Walton multiplier?

Never tried that above 40 kHz or so, but why not.
But it only takes .7 V to open a NPN, 150 mV for a Ge.
And you can bias the detector - side to reduce that.

I tried forward biasing my schottky diode, but it didn't give me any
more detector output from RF off to RF on. I think there is theory to
support that observation.

These BAT15-99 have a very low voltage drop for low currents:
http://panteltje.com/pub/bat15-99.gif
If there is more than one pulse then the filter C will be charged and a very low current should flow?

I meant this way of biasing the detector:
http://panteltje.com/pub/detector_IMG_6902.JPG

 

[John Larkin]

On Wed, 08 May 2019 16:06:46 GMT, Jan Panteltje
<pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Wed, 08 May 2019 07:21:47 -0700) it happened John Larkin
jjlarkin@highlandtechnology.com> wrote in
l5p5de9rj05hvl8a4rhd1hkem929vmplf0@4ax.com>:

On Wed, 08 May 2019 07:41:32 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Tue, 07 May 2019 20:21:13 -0700) it happened John Larkin
jjlarkin@highlandtechnology.com> wrote in
c9i4de5apteq5en9qggebr22qgqn6t31hr@4ax.com>:

On Thu, 02 May 2019 20:15:21 -0700, John Larkin
jjlarkin@highlandtechnology.com> wrote:


I'll have a LVDS signal with data or a square wave, in the range of
maybe 1 MHz to 2 GHz. I figure I can pump it through an 10EP89 ECL
buffer to give it some heft. Each output will become almost 2 volts
p-p.

I'd like to light an LED if there is signal present. How does this
look?

https://www.dropbox.com/s/bvyjs4zgyprx3tu/Sig_Indicator.JPG?dl=0

The 10 pF caps shouldn't load my signals much, especially in the lower
signal path that doesn't need to be super fast.

I suppose I could buy some fancy RF detector chip, but I'd rather just
use fairly ordinary parts.

Any other ideas?

Looks like I might have an unused CML differential output from a logic
fanout chip. Here's a detector that drives a single schottky diode
differentially.

https://www.dropbox.com/s/7zo9kmiuhs532ww/CML_SD2.jpg?dl=0

That sweep is from 0 to 5 GHz.

I'm using the CML gate outputs unterminated, which I think puts -16 mA
alternately into its internal 50 ohm resistors, 800 mV p-p at each
pin.

Would this work? BAT15-099 0.35 pF 12 GHz 5.5 Ohm forward ~.3 V
http://panteltje.com/pub/detector_IMG_6900.JPG

Yes, that works. I might be wrong about the CML swing (gotta verify
that) which is officially 400 mv p-p at each pin when externally
terminated. I'm not terminating so I expect 0.8 p-p. The 2-diode
voltage doubler would be a little wimpy if each one only sees 0.4 p-p.

My 1-diode thing works usably at 0.4 p-p.

How fast can one do a Cockcroft–Walton multiplier?

Never tried that above 40 kHz or so, but why not.
But it only takes .7 V to open a NPN, 150 mV for a Ge.
And you can bias the detector - side to reduce that.

I tried forward biasing my schottky diode, but it didn't give me any
more detector output from RF off to RF on. I think there is theory to
support that observation.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[whit3rd]

On Wednesday, May 8, 2019 at 7:21:54 AM UTC-7, John Larkin wrote:

> How fast can one do a Cockcroft匨alton multiplier?

A few gigahertz, certainly. That's not the only option, though.
Rectenna is a good keyword to search on:

<https://www.mwrf.com/systems/rectenna-serves-245-ghz-wireless-power-transmission>

 

[John Larkin]

On Wed, 08 May 2019 17:25:53 GMT, Jan Panteltje
<pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Wed, 08 May 2019 09:48:00 -0700) it happened John Larkin
jjlarkin@highlandtechnology.com> wrote in
3t16de5pdfm9qnki9a1sqal1n0lomp5v5v@4ax.com>:

On Wed, 08 May 2019 16:06:46 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Wed, 08 May 2019 07:21:47 -0700) it happened John Larkin
jjlarkin@highlandtechnology.com> wrote in
l5p5de9rj05hvl8a4rhd1hkem929vmplf0@4ax.com>:

On Wed, 08 May 2019 07:41:32 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Tue, 07 May 2019 20:21:13 -0700) it happened John Larkin
jjlarkin@highlandtechnology.com> wrote in
c9i4de5apteq5en9qggebr22qgqn6t31hr@4ax.com>:

On Thu, 02 May 2019 20:15:21 -0700, John Larkin
jjlarkin@highlandtechnology.com> wrote:


I'll have a LVDS signal with data or a square wave, in the range of
maybe 1 MHz to 2 GHz. I figure I can pump it through an 10EP89 ECL
buffer to give it some heft. Each output will become almost 2 volts
p-p.

I'd like to light an LED if there is signal present. How does this
look?

https://www.dropbox.com/s/bvyjs4zgyprx3tu/Sig_Indicator.JPG?dl=0

The 10 pF caps shouldn't load my signals much, especially in the lower
signal path that doesn't need to be super fast.

I suppose I could buy some fancy RF detector chip, but I'd rather just
use fairly ordinary parts.

Any other ideas?

Looks like I might have an unused CML differential output from a logic
fanout chip. Here's a detector that drives a single schottky diode
differentially.

https://www.dropbox.com/s/7zo9kmiuhs532ww/CML_SD2.jpg?dl=0

That sweep is from 0 to 5 GHz.

I'm using the CML gate outputs unterminated, which I think puts -16 mA
alternately into its internal 50 ohm resistors, 800 mV p-p at each
pin.

Would this work? BAT15-099 0.35 pF 12 GHz 5.5 Ohm forward ~.3 V
http://panteltje.com/pub/detector_IMG_6900.JPG

Yes, that works. I might be wrong about the CML swing (gotta verify
that) which is officially 400 mv p-p at each pin when externally
terminated. I'm not terminating so I expect 0.8 p-p. The 2-diode
voltage doubler would be a little wimpy if each one only sees 0.4 p-p.

My 1-diode thing works usably at 0.4 p-p.

How fast can one do a Cockcroft–Walton multiplier?

Never tried that above 40 kHz or so, but why not.
But it only takes .7 V to open a NPN, 150 mV for a Ge.
And you can bias the detector - side to reduce that.

I tried forward biasing my schottky diode, but it didn't give me any
more detector output from RF off to RF on. I think there is theory to
support that observation.

These BAT15-99 have a very low voltage drop for low currents:
http://panteltje.com/pub/bat15-99.gif
If there is more than one pulse then the filter C will be charged and a very low current should flow?

I meant this way of biasing the detector:
http://panteltje.com/pub/detector_IMG_6902.JPG

I'm going to use a comparator (or an opamp as a comparator) between
the detector and the LED. Less risk.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[Jan Panteltje]

On a sunny day (Wed, 08 May 2019 19:51:37 -0700) it happened John Larkin
<jjlarkin@highlandtechnology.com> wrote in
<6b57depl94s548ocp6mq4iaq7kv3n1hft3@4ax.com>:

On Wed, 08 May 2019 07:41:32 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:
These BAT15-99 have a very low voltage drop for low currents:
http://panteltje.com/pub/bat15-99.gif
If there is more than one pulse then the filter C will be charged and a very low current should flow?

I meant this way of biasing the detector:
http://panteltje.com/pub/detector_IMG_6902.JPG

I'm going to use a comparator (or an opamp as a comparator) between
the detector and the LED. Less risk.

Yes of course, maybe a LM324 ;-)

I am doing some audio phase shift thing with some TLC274ACN right now... 5 mV offset, does not matter because AC only.
driving an AD8346 QAM modulator to make 2.4 GHz SSB.

 

[Bill Sloman]

On Saturday, May 4, 2019 at 10:41:42 PM UTC+10, Cursitor Doom wrote:

On Fri, 03 May 2019 11:30:58 -0700, John Larkin wrote:

This is RF, and I don't do RF!

Can't say I blame you. It's a bit of a black art which gets blacker the
higher in frequency you go. Best avoided!

Quick though.

--
Bill Sloman, Sydney

 

[Bill Sloman]

On Sunday, May 5, 2019 at 2:35:12 AM UTC+10, Cursitor Doom wrote:

On Sat, 04 May 2019 08:27:53 -0700, Joerg wrote:

Yeah, but "real men's RF" is discrete.

Exactly. Conquering all those instabilities, strays and parasitics
fearlessly head-on. Not suitable for wimmin or gays.

None of the RF specialists I've run into has been aggressively butch.

It isn't an area where gender or sexual preferences is likely to have a significant effect on performance. Cursitor Doom may differ but he has silly ideas about wide variety of areas. A renaissence half-wit.

--
Bill Sloman, Sydney

 

[John Larkin]

On Thu, 09 May 2019 06:13:14 GMT, Jan Panteltje
<pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Wed, 08 May 2019 19:51:37 -0700) it happened John Larkin
jjlarkin@highlandtechnology.com> wrote in
6b57depl94s548ocp6mq4iaq7kv3n1hft3@4ax.com>:


On Wed, 08 May 2019 07:41:32 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:
These BAT15-99 have a very low voltage drop for low currents:
http://panteltje.com/pub/bat15-99.gif
If there is more than one pulse then the filter C will be charged and a very low current should flow?

I meant this way of biasing the detector:
http://panteltje.com/pub/detector_IMG_6902.JPG

I'm going to use a comparator (or an opamp as a comparator) between
the detector and the LED. Less risk.

Yes of course, maybe a LM324 ;-)

I am doing some audio phase shift thing with some TLC274ACN right now... 5 mV offset, does not matter because AC only.
driving an AD8346 QAM modulator to make 2.4 GHz SSB.

We just failed at doing a wideband I/Q modulator to simulate a jet
engine blade-tip sensor. Certain Parties convinced me to go over the
top, including a super-wideband all-pass 90 degree shifter which was
too clever by at least half.

https://www.dropbox.com/s/dghx81mb074ksvj/DSC03292.JPG?dl=0

Basically, everything oscillated. There were some distortion issues
too.

So we're laying out rev B, which will be much simpler and will work
only at the customer's fixed frequency. Those big Phoenix blocks are
versatile but are also antennas.

Pity. We usually get rev A right.


--

John Larkin Highland Technology, Inc

lunatic fringe electronics

 

[Jan Panteltje]

On a sunny day (Thu, 09 May 2019 06:57:57 -0700) it happened John Larkin
<jjlarkin@highlandtechnology.com> wrote in
<vob8de5iclr7o2kslvvgfi3909tq6v3iul@4ax.com>:

On Thu, 09 May 2019 06:13:14 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:

On a sunny day (Wed, 08 May 2019 19:51:37 -0700) it happened John Larkin
jjlarkin@highlandtechnology.com> wrote in
6b57depl94s548ocp6mq4iaq7kv3n1hft3@4ax.com>:


On Wed, 08 May 2019 07:41:32 GMT, Jan Panteltje
pNaOnStPeAlMtje@yahoo.com> wrote:
These BAT15-99 have a very low voltage drop for low currents:
http://panteltje.com/pub/bat15-99.gif
If there is more than one pulse then the filter C will be charged and a very low current should flow?

I meant this way of biasing the detector:
http://panteltje.com/pub/detector_IMG_6902.JPG

I'm going to use a comparator (or an opamp as a comparator) between
the detector and the LED. Less risk.

Yes of course, maybe a LM324 ;-)

I am doing some audio phase shift thing with some TLC274ACN right now... 5 mV offset, does not matter because AC only.
driving an AD8346 QAM modulator to make 2.4 GHz SSB.


We just failed at doing a wideband I/Q modulator to simulate a jet
engine blade-tip sensor. Certain Parties convinced me to go over the
top, including a super-wideband all-pass 90 degree shifter which was
too clever by at least half.

https://www.dropbox.com/s/dghx81mb074ksvj/DSC03292.JPG?dl=0

Basically, everything oscillated. There were some distortion issues
too.

So we're laying out rev B, which will be much simpler and will work
only at the customer's fixed frequency. Those big Phoenix blocks are
versatile but are also antennas.

Pity. We usually get rev A right.

Yes, PCBs make things difficult to change....

I have this DVBS transmitter, controlled by a raspberry Pi computer, works very well:
http://panteltje.com/pub/DVBS_transmitter_for_SSB_IMG_6908.JPG
it gets it frequency from an ebay board with ADF4350 and TCXO, also controlled by same raspberry.
This is not the same circuit as on my website.

This is for video, I thought: 'I have transport stream IQ from the root-cosine filter,
why not generate IQ for SSB the antique way with a 90 degrees phase shifter?',
so cut the coils to the AD8346 driver, and connected an audio socket to it.
Made a little phase shifter board:
http://panteltje.com/pub/audio_90_degrees_phase_shifter_top_IMG_6903.JPG
You may wonder why all the trimpots, well it requires precision resistors
and I had a bag full of 10 turn pots from ebay, so, Ohm meter to 1 Ohm accurate.
Did not have 1% caps at hand so tried +-10% Chinese ones
http://panteltje.com/pub/audio_90_degrees_phase_shifter_bottom_IMG_6904.JPG
Anna Lyser showed great carrier suppression (in the noise), but only 10 dB sideband suppression with those caps, and an LM324 with cross over distortion,
got the TLC274ACN now, and some 1% caps yesterday, but those are so big...
The 2.4 GHz output will have to be amplified, again ebay to the rescue with 5 pieces RF2126 chips:
http://panteltje.com/pub/RF2126_1W_2.4GHz_linear_top_IMG_6913.JPG
The wiring will be interesting, the cooling too, soldered a 2 mm screw on the back of the chip,
sticks through the board, maybe heatsink on it?
http://panteltje.com/pub/RF2126_1W_2.4GHz_linear_bottom_IMG_6912.JPG

PCBs ...

Now I need some courage to build the rest.

 

[Joerg]

On 2019-05-05 10:51, Phil Hobbs wrote:

On 5/5/19 10:10 AM, Joerg wrote:
On 2019-05-04 13:58, John Larkin wrote:
On Sat, 04 May 2019 12:13:26 -0700, Joerg <news@analogconsultants.com
wrote:

On 2019-05-04 08:31, John Larkin wrote:

[...]

If I use a Hittite HMC987 fanout chip, I can use one of its diff ECL
outputs just for the monitor LED, and I can load that as hard as I
like.

https://www.dropbox.com/s/avw42lia7ejayug/Sig_Indicator_3.JPG?dl=0

That Hittite chip is $20.


Ouch!

It's wonderful. If it helps me sell a bunch of $1500 boxes, it's a
bargain. The CML comparator ahead of it costs almost as much.

We're looking at some distributed amplifier chips in the $200-400
range, and some fast logic gates for $70 each.


Yes, but to say it like a greedy Wall Street banker, how much higher
could the profit have been?

No kidding, I had projects where stuff retailed well north of $100,
the per unit cost was $10 and the client asked "Could we do it for
$5?". So we did.


We do an ultralow noise digital laser controller with a BOM cost of $37
including the board and connectors, excluding the diode laser and the
optomechanics. It replaces a $3500 purchased laser. It's way more fun
doing stuff for cheap like that.

Yes! I am helping with a similar project (not laser) right now. Most
engineers roll their eyes when a boss or a manager asks "Can we shave
another $2 from the BOM"? With me my eyes light up, it's fun.

Right now I had to pause, can't visit the client. The handlebar of my
road bike snapped off at full speed during an after-church ride and ...

--
Regards, Joerg

http://www.analogconsultants.com/

 

[Joerg]

On 2019-05-05 08:56, John Larkin wrote:

On Sun, 05 May 2019 08:40:10 -0700, Joerg <news@analogconsultants.com
wrote:

On 2019-05-05 08:12, John Larkin wrote:
On Sun, 05 May 2019 07:10:00 -0700, Joerg <news@analogconsultants.com
wrote:

On 2019-05-04 13:58, John Larkin wrote:
On Sat, 04 May 2019 12:13:26 -0700, Joerg <news@analogconsultants.com
wrote:

On 2019-05-04 08:31, John Larkin wrote:
On Sat, 04 May 2019 07:03:47 -0700, Joerg <news@analogconsultants.com
wrote:

On 2019-05-03 08:18, John Larkin wrote:
On Fri, 3 May 2019 06:41:33 -0000 (UTC), Jasen Betts
jasen@xnet.co.nz> wrote:

On 2019-05-03, John Larkin <jjlarkin@highlandtechnology.com> wrote:

I'll have a LVDS signal with data or a square wave, in the range of
maybe 1 MHz to 2 GHz. I figure I can pump it through an 10EP89 ECL
buffer to give it some heft. Each output will become almost 2 volts
p-p.

I'd like to light an LED if there is signal present. How does this
look?

https://www.dropbox.com/s/bvyjs4zgyprx3tu/Sig_Indicator.JPG?dl=0

The 10 pF caps shouldn't load my signals much, especially in the lower
signal path that doesn't need to be super fast.

I suppose I could buy some fancy RF detector chip, but I'd rather just
use fairly ordinary parts.

Any other ideas?

maybe use transistors instead of diodes?

Yes. BFT25 maybe, 5 GHz Ft.


Probably an ordinary BFS17 would also do. RC series in front of the
base, base at near zero DC via another resistive path. The BE junction
rectifies some and then an LED in the collector path is lit. Very little
base current will do because modern LED in the collector path at 1mA can
generate light that is uncomfortably bright. It'll pulse but very fast.

It is not very elegant but less parts.

BFS17 is great precisely because it's fast but not too fast. But
probably a tad slow to detect 2 GHz. Ft is just about 2 GHz.


That's ok, you aren't relying on it being a perfect amplifier. Only to
have the BE junction rectify a little and cause enough CE current to
keep an LED lit. The LED won't see much of the RF. In essence the same
that happens in EMI cases but where this isn't desired, where cell phone
RF >1GHz rectifies itself at the first BE junction of even slow opamps
and causes a demodulated signal in the output.


The dual doubler thing looks good, from a few hundred KHz to over 2
GHz, with 5 pF loading on each side of my diff ECL logic.

https://www.dropbox.com/s/axonmf82uzxhpyi/Sig_Indicator_2.JPG?dl=0


Nice but that's a lot of parts.

With ECL swings, about 800 mV p-p, it works better with fewer diodes:

https://www.dropbox.com/s/xndruojyp819042/Sig_Indicator_4.JPG?dl=0

Then an opamp to drive the LED.


That works. Still feels like cheating not to do it the old-school way.

Solid-state diodes were invented before tubes!


But the opamp, the opamp. When I was young, around 20, I never used
opamps. It was all discretes. Tubes for the big stuff.

I made my own little opamps, about a square inch of PCB with wires
sticking out one side, a SIP basically. Started with a pair of
brand-new GE NPN plastic transistors. By selecting one resistor, I
could trim them to 1 uV/degC.

I tried to milk individual transistors in single-stage for what they
got. RF types I had to socket. In Europe they cost so much in the early
70's that they had to be shared between homemade measurement tools. Sort
of a musical transistor.

My first VHF amp had a Motorola RF transistor in it but it was only
affordable because it was a reject, multi-emitter version with some of
them blown. So instead of the typical 10W I only got 6W out of it which
was fine and within budget. Because the beer budget was absolutely not
to be sacrificed for stuff like that.

If I use a Hittite HMC987 fanout chip, I can use one of its diff ECL
outputs just for the monitor LED, and I can load that as hard as I
like.

https://www.dropbox.com/s/avw42lia7ejayug/Sig_Indicator_3.JPG?dl=0

That Hittite chip is $20.


Ouch!

It's wonderful. If it helps me sell a bunch of $1500 boxes, it's a
bargain. The CML comparator ahead of it costs almost as much.

We're looking at some distributed amplifier chips in the $200-400
range, and some fast logic gates for $70 each.


Yes, but to say it like a greedy Wall Street banker, how much higher
could the profit have been?

No kidding, I had projects where stuff retailed well north of $100, the
per unit cost was $10 and the client asked "Could we do it for $5?". So
we did.


We compute "direct cost" of a product: parts cost + unburnened
assembly and test labor cost. Selling price has to be at least 3x,
preferably 6x to the occasional 10x. That works in our business.


Sound like good margins. For us guys it's ok as long as it pays the tab
at Zeitgeist and similar places.

Alas, Z is a long walk from our new place. But there is a great dive
bar 2 blocks away.

That is sorely lacking where I live. In Rancho Cordova where I used to
work a long time ago that's now different. They started calling that
area "Craft District" because there is almost a dozen breweries with tap
rooms.

https://s3-media3.fl.yelpcdn.com/bphoto/_NS_qVcs3KRux2kpd72hoQ/o.jpg

There are businesses that charge 50x.


That is why there is (was?) a Ferrari dealership in the Bay Area.


For low volume stuff, the development and support costs are serious.


True. I don't get involved in too much low volume stuff. In the
beginning it may be but then it usually takes off. So far the topper is
a design that runs off the assembly line unchanged since 1994. At one
point this client asked me to indentify all resistors than could be
changed to 10% and to untrimmed (typically meaning 30%). Cost them 1/4h
of my time and they made that back probably within the month.

Wow, untrimmed resistors. What do they cost in the millions?

IIRC the cost difference was more than 0.1c/piece versus trimmed (Asian
pricing) and that ended up making a substantial difference. Designing
mass products can be fun.

--
Regards, Joerg

http://www.analogconsultants.com/

 

[Clifford Heath]

On 10/5/19 5:16 am, Joerg wrote:

On 2019-05-05 10:51, Phil Hobbs wrote:
On 5/5/19 10:10 AM, Joerg wrote:
On 2019-05-04 13:58, John Larkin wrote:
On Sat, 04 May 2019 12:13:26 -0700, Joerg <news@analogconsultants.com
wrote:

On 2019-05-04 08:31, John Larkin wrote:

[...]


If I use a Hittite HMC987 fanout chip, I can use one of its diff ECL
outputs just for the monitor LED, and I can load that as hard as I
like.

https://www.dropbox.com/s/avw42lia7ejayug/Sig_Indicator_3.JPG?dl=0

That Hittite chip is $20.


Ouch!

It's wonderful. If it helps me sell a bunch of $1500 boxes, it's a
bargain. The CML comparator ahead of it costs almost as much.

We're looking at some distributed amplifier chips in the $200-400
range, and some fast logic gates for $70 each.


Yes, but to say it like a greedy Wall Street banker, how much higher
could the profit have been?

No kidding, I had projects where stuff retailed well north of $100,
the per unit cost was $10 and the client asked "Could we do it for
$5?". So we did.


We do an ultralow noise digital laser controller with a BOM cost of $37
including the board and connectors, excluding the diode laser and the
optomechanics.  It replaces a $3500 purchased laser.  It's way more fun
doing stuff for cheap like that.


Yes! I am helping with a similar project (not laser) right now. Most
engineers roll their eyes when a boss or a manager asks "Can we shave
another $2 from the BOM"? With me my eyes light up, it's fun.

Right now I had to pause, can't visit the client. The handlebar of my
road bike snapped off at full speed during an after-church ride and ...

Yowsers, that sounds intense, I'm glad you're still able to type.
Was there no early indication of imminent failure?

Clifford Heath.

 

[Joerg]

On 2019-05-09 17:46, Clifford Heath wrote:

On 10/5/19 5:16 am, Joerg wrote:
On 2019-05-05 10:51, Phil Hobbs wrote:
On 5/5/19 10:10 AM, Joerg wrote:
On 2019-05-04 13:58, John Larkin wrote:
On Sat, 04 May 2019 12:13:26 -0700, Joerg <news@analogconsultants.com
wrote:

On 2019-05-04 08:31, John Larkin wrote:

[...]


If I use a Hittite HMC987 fanout chip, I can use one of its diff ECL
outputs just for the monitor LED, and I can load that as hard as I
like.

https://www.dropbox.com/s/avw42lia7ejayug/Sig_Indicator_3.JPG?dl=0

That Hittite chip is $20.


Ouch!

It's wonderful. If it helps me sell a bunch of $1500 boxes, it's a
bargain. The CML comparator ahead of it costs almost as much.

We're looking at some distributed amplifier chips in the $200-400
range, and some fast logic gates for $70 each.


Yes, but to say it like a greedy Wall Street banker, how much higher
could the profit have been?

No kidding, I had projects where stuff retailed well north of $100,
the per unit cost was $10 and the client asked "Could we do it for
$5?". So we did.


We do an ultralow noise digital laser controller with a BOM cost of $37
including the board and connectors, excluding the diode laser and the
optomechanics. It replaces a $3500 purchased laser. It's way more fun
doing stuff for cheap like that.


Yes! I am helping with a similar project (not laser) right now. Most
engineers roll their eyes when a boss or a manager asks "Can we shave
another $2 from the BOM"? With me my eyes light up, it's fun.

Right now I had to pause, can't visit the client. The handlebar of my
road bike snapped off at full speed during an after-church ride and ...


Yowsers, that sounds intense, I'm glad you're still able to type.

Well, it's been a week now and still hobbling around. Can't work much.
Hopefully the left foot will heal up. OTOH I am glad this didn't happen
1/2h earlier where I was roaring down a steep hill at 42mph with big
pointy boulders on the side and a T-intersection into a busy road at the
end of this hill.

The other good thing was that three drivers stopped and almost got into
an argument about who gets to take me and my bike home, despite me
bleeding a lot. There are many good people in our society. There was no
way I could have made it home by myself.

Was there no early indication of imminent failure?

Absolutely nothing. It just snapped out of the blue, like in his case:

https://www.youtube.com/watch?v=dPEfiN0s-KA

The whole right side starting almost at the stem was suddenly gone. I
will never use aluminum for a handlebar again. And no carbon fiber, of
course. Most likely my road bike gets a straight steel handlebar now.
First I'll have to check it's frame for impact damage. Once I can walk
again ...

--
Regards, Joerg

http://www.analogconsultants.com/

 

[John Larkin]

On Fri, 3 May 2019 08:58:40 +0100, Clive Arthur
<cliveta@nowaytoday.co.uk> wrote:

On 03/05/2019 04:15, John Larkin wrote:

I'll have a LVDS signal with data or a square wave, in the range of
maybe 1 MHz to 2 GHz. I figure I can pump it through an 10EP89 ECL
buffer to give it some heft. Each output will become almost 2 volts
p-p.

I'd like to light an LED if there is signal present. How does this
look?

https://www.dropbox.com/s/bvyjs4zgyprx3tu/Sig_Indicator.JPG?dl=0

The 10 pF caps shouldn't load my signals much, especially in the lower
signal path that doesn't need to be super fast.

I suppose I could buy some fancy RF detector chip, but I'd rather just
use fairly ordinary parts.

Any other ideas?


You could measure the current taken by the buffer. Well, you did say
'any other ideas'.

Cheers

OK, drive a cmos gate with the clock, maybe add an extra capacitor on
the output to ground. Vcc (and ground!) current will increase linearly
with frequency.

That's cute. A small bypassed resistor from gate ground pin to PCB
ground will make a small voltage that can feed two comparators. A few
tenths of a volt there won't bother anything. It could be done on the
high side too, let Vcc droop a bit as frequency goes up.

Nice idea, as long as it's a CMOS gate and not ECL.

It's a charge dispenser.



--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

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

 

[John Larkin]

On Mon, 13 May 2019 13:09:21 -0700 (PDT), George Herold
<gherold@teachspin.com> wrote:

On Monday, May 13, 2019 at 3:18:05 PM UTC-4, Joerg wrote:
On 2019-05-09 17:46, Clifford Heath wrote:
On 10/5/19 5:16 am, Joerg wrote:
On 2019-05-05 10:51, Phil Hobbs wrote:
On 5/5/19 10:10 AM, Joerg wrote:
On 2019-05-04 13:58, John Larkin wrote:
On Sat, 04 May 2019 12:13:26 -0700, Joerg <news@analogconsultants.com
wrote:

On 2019-05-04 08:31, John Larkin wrote:

[...]


If I use a Hittite HMC987 fanout chip, I can use one of its diff ECL
outputs just for the monitor LED, and I can load that as hard as I
like.

https://www.dropbox.com/s/avw42lia7ejayug/Sig_Indicator_3.JPG?dl=0

That Hittite chip is $20.


Ouch!

It's wonderful. If it helps me sell a bunch of $1500 boxes, it's a
bargain. The CML comparator ahead of it costs almost as much.

We're looking at some distributed amplifier chips in the $200-400
range, and some fast logic gates for $70 each.


Yes, but to say it like a greedy Wall Street banker, how much higher
could the profit have been?

No kidding, I had projects where stuff retailed well north of $100,
the per unit cost was $10 and the client asked "Could we do it for
$5?". So we did.


We do an ultralow noise digital laser controller with a BOM cost of $37
including the board and connectors, excluding the diode laser and the
optomechanics. It replaces a $3500 purchased laser. It's way more fun
doing stuff for cheap like that.


Yes! I am helping with a similar project (not laser) right now. Most
engineers roll their eyes when a boss or a manager asks "Can we shave
another $2 from the BOM"? With me my eyes light up, it's fun.

Right now I had to pause, can't visit the client. The handlebar of my
road bike snapped off at full speed during an after-church ride and ...


Yowsers, that sounds intense, I'm glad you're still able to type.


Well, it's been a week now and still hobbling around. Can't work much.
Hopefully the left foot will heal up. OTOH I am glad this didn't happen
1/2h earlier where I was roaring down a steep hill at 42mph with big
pointy boulders on the side and a T-intersection into a busy road at the
end of this hill.

The other good thing was that three drivers stopped and almost got into
an argument about who gets to take me and my bike home, despite me
bleeding a lot. There are many good people in our society. There was no
way I could have made it home by myself.


Was there no early indication of imminent failure?


Absolutely nothing. It just snapped out of the blue, like in his case:

https://www.youtube.com/watch?v=dPEfiN0s-KA

The whole right side starting almost at the stem was suddenly gone. I
will never use aluminum for a handlebar again. And no carbon fiber, of
course. Most likely my road bike gets a straight steel handlebar now.
First I'll have to check it's frame for impact damage. Once I can walk
again ...

--
Regards, Joerg

http://www.analogconsultants.com/

Hey Joerg, maybe it's time you slowed down and got one of those
three wheeled bikes with a basket in the back. :^)

Ducks,
George H.

Golf cart.


--

John Larkin Highland Technology, Inc
picosecond timing precision measurement

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

 

[George Herold]

On Monday, May 13, 2019 at 3:18:05 PM UTC-4, Joerg wrote:

On 2019-05-09 17:46, Clifford Heath wrote:
On 10/5/19 5:16 am, Joerg wrote:
On 2019-05-05 10:51, Phil Hobbs wrote:
On 5/5/19 10:10 AM, Joerg wrote:
On 2019-05-04 13:58, John Larkin wrote:
On Sat, 04 May 2019 12:13:26 -0700, Joerg <news@analogconsultants.com
wrote:

On 2019-05-04 08:31, John Larkin wrote:

[...]


If I use a Hittite HMC987 fanout chip, I can use one of its diff ECL
outputs just for the monitor LED, and I can load that as hard as I
like.

https://www.dropbox.com/s/avw42lia7ejayug/Sig_Indicator_3.JPG?dl=0

That Hittite chip is $20.


Ouch!

It's wonderful. If it helps me sell a bunch of $1500 boxes, it's a
bargain. The CML comparator ahead of it costs almost as much.

We're looking at some distributed amplifier chips in the $200-400
range, and some fast logic gates for $70 each.


Yes, but to say it like a greedy Wall Street banker, how much higher
could the profit have been?

No kidding, I had projects where stuff retailed well north of $100,
the per unit cost was $10 and the client asked "Could we do it for
$5?". So we did.


We do an ultralow noise digital laser controller with a BOM cost of $37
including the board and connectors, excluding the diode laser and the
optomechanics. It replaces a $3500 purchased laser. It's way more fun
doing stuff for cheap like that.


Yes! I am helping with a similar project (not laser) right now. Most
engineers roll their eyes when a boss or a manager asks "Can we shave
another $2 from the BOM"? With me my eyes light up, it's fun.

Right now I had to pause, can't visit the client. The handlebar of my
road bike snapped off at full speed during an after-church ride and ...


Yowsers, that sounds intense, I'm glad you're still able to type.


Well, it's been a week now and still hobbling around. Can't work much.
Hopefully the left foot will heal up. OTOH I am glad this didn't happen
1/2h earlier where I was roaring down a steep hill at 42mph with big
pointy boulders on the side and a T-intersection into a busy road at the
end of this hill.

The other good thing was that three drivers stopped and almost got into
an argument about who gets to take me and my bike home, despite me
bleeding a lot. There are many good people in our society. There was no
way I could have made it home by myself.


Was there no early indication of imminent failure?


Absolutely nothing. It just snapped out of the blue, like in his case:

https://www.youtube.com/watch?v=dPEfiN0s-KA

The whole right side starting almost at the stem was suddenly gone. I
will never use aluminum for a handlebar again. And no carbon fiber, of
course. Most likely my road bike gets a straight steel handlebar now.
First I'll have to check it's frame for impact damage. Once I can walk
again ...

--
Regards, Joerg

http://www.analogconsultants.com/

Hey Joerg, maybe it's time you slowed down and got one of those
three wheeled bikes with a basket in the back. :^)

Ducks,
George H.