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On Mon, 22 Jul 2019 11:15:57 +1000, Clifford Heath
no.spam@please.net> wrote:
On 21/7/19 9:56 am, Piotr Wyderski wrote:
John Larkin wrote:
I get to teach a young engineer my Dremeling secrets.
I am not able to produce decent PCBs that way, but ...
I grew up using a dental drill we had at home, so I'm ok freehand, but...
I've set a Dremel drill press up with the minimum bit height just at the
bottom of the copper. It's trivial to slide the PCB under it in nice
straight lines, but it really needs two hands. I'm considering attaching
a foot pedal to the lever that drops the bit down, to free the second
hand. It would be trivial to achieve results better than John's
freehand, that way.
Clifford Heath.
The copper carving is artistic but fundamentally insignificant. The
"results" that matter are the circuit performance.
On 22/7/19 1:13 pm, John Larkin wrote:
On Mon, 22 Jul 2019 11:15:57 +1000, Clifford Heath
no.spam@please.net> wrote:
On 21/7/19 9:56 am, Piotr Wyderski wrote:
John Larkin wrote:
I get to teach a young engineer my Dremeling secrets.
I am not able to produce decent PCBs that way, but ...
I grew up using a dental drill we had at home, so I'm ok freehand, but...
I've set a Dremel drill press up with the minimum bit height just at the
bottom of the copper. It's trivial to slide the PCB under it in nice
straight lines, but it really needs two hands. I'm considering attaching
a foot pedal to the lever that drops the bit down, to free the second
hand. It would be trivial to achieve results better than John's
freehand, that way.
Clifford Heath.
The copper carving is artistic but fundamentally insignificant. The
"results" that matter are the circuit performance.
Yes, and really straight cuts (without needing a lot of practise) would
help with that.
mandag den 22. juli 2019 kl. 09.27.07 UTC+2 skrev Clifford Heath:
On 22/7/19 1:13 pm, John Larkin wrote:
On Mon, 22 Jul 2019 11:15:57 +1000, Clifford Heath
no.spam@please.net> wrote:
On 21/7/19 9:56 am, Piotr Wyderski wrote:
John Larkin wrote:
I get to teach a young engineer my Dremeling secrets. I am not
able to produce decent PCBs that way, but ...
I grew up using a dental drill we had at home, so I'm ok freehand,
but...
I've set a Dremel drill press up with the minimum bit height just at
the bottom of the copper. It's trivial to slide the PCB under it in
nice straight lines, but it really needs two hands. I'm considering
attaching
a foot pedal to the lever that drops the bit down, to free the
second
hand. It would be trivial to achieve results better than John's
freehand, that way.
Clifford Heath.
The copper carving is artistic but fundamentally insignificant. The
"results" that matter are the circuit performance.
Yes, and really straight cuts (without needing a lot of practise) would
help with that.
make a simple pantograph, stylus sets the cutting depth and it would be
easy to follow a straight edge to do lines
Lasse Langwadt Christensen <langwadt@fonz.dk> wrote:
mandag den 22. juli 2019 kl. 09.27.07 UTC+2 skrev Clifford Heath:
On 22/7/19 1:13 pm, John Larkin wrote:
On Mon, 22 Jul 2019 11:15:57 +1000, Clifford Heath
no.spam@please.net> wrote:
On 21/7/19 9:56 am, Piotr Wyderski wrote:
John Larkin wrote:
I get to teach a young engineer my Dremeling secrets. I am not
able to produce decent PCBs that way, but ...
I grew up using a dental drill we had at home, so I'm ok freehand,
but...
I've set a Dremel drill press up with the minimum bit height just at
the bottom of the copper. It's trivial to slide the PCB under it in
nice straight lines, but it really needs two hands. I'm considering
attaching
a foot pedal to the lever that drops the bit down, to free the
second
hand. It would be trivial to achieve results better than John's
freehand, that way.
Clifford Heath.
The copper carving is artistic but fundamentally insignificant. The
"results" that matter are the circuit performance.
Yes, and really straight cuts (without needing a lot of practise) would
help with that.
make a simple pantograph, stylus sets the cutting depth and it would be
easy to follow a straight edge to do lines
Do not chop the copper, especially for high speed circuits.
On 22/7/19 1:13 pm, John Larkin wrote:
On Mon, 22 Jul 2019 11:15:57 +1000, Clifford Heath
no.spam@please.net> wrote:
On 21/7/19 9:56 am, Piotr Wyderski wrote:
John Larkin wrote:
I get to teach a young engineer my Dremeling secrets.
I am not able to produce decent PCBs that way, but ...
I grew up using a dental drill we had at home, so I'm ok freehand, but...
I've set a Dremel drill press up with the minimum bit height just at the
bottom of the copper. It's trivial to slide the PCB under it in nice
straight lines, but it really needs two hands. I'm considering attaching
a foot pedal to the lever that drops the bit down, to free the second
hand. It would be trivial to achieve results better than John's
freehand, that way.
Clifford Heath.
The copper carving is artistic but fundamentally insignificant. The
"results" that matter are the circuit performance.
Yes, and really straight cuts (without needing a lot of practise) would
help with that.
On Mon, 22 Jul 2019 13:39:06 GMT, Steve Wilson <no@spam.com> wrote:
Do not chop the copper, especially for high speed circuits.
Carving the topside copper is the best way to do really fast stuff. It
allows one to run a 50 ohm coplanar waveguide into an edge-launch SMA.
So? You can do the same on a small pcb, then mount it on a larger ground
plane to put the following circuitry.
You are not going to do really fast sstuff on FR4. You need Rogers or
similar, which is very expensive to put on a pcb. So use a small piece
of Rogers for the fast stuff, and a larger copperclad for the supporting
circuits.
On Mon, 22 Jul 2019 13:39:06 GMT, Steve Wilson <no@spam.com> wrote:
Do not chop the copper, especially for high speed circuits.
Carving the topside copper is the best way to do really fast stuff. It
allows one to run a 50 ohm coplanar waveguide into an edge-launch SMA.
We need 28 volts p-p at 14 MHz to test our IQ modulator box. I've
bought two Chinese RF amps from Amazon and both are garbage. So we're
going to build our own class C amp, as a dremel'd prototype.
https://www.dropbox.com/s/tq8qsvc7lbfirmh/Z468_WB_1.png?raw=1
I get to teach a young engineer my Dremeling secrets.
On Mon, 22 Jul 2019 05:34:50 -0700 (PDT), Lasse Langwadt Christensen
langwadt@fonz.dk> wrote:
mandag den 22. juli 2019 kl. 09.27.07 UTC+2 skrev Clifford Heath:
On 22/7/19 1:13 pm, John Larkin wrote:
On Mon, 22 Jul 2019 11:15:57 +1000, Clifford Heath
no.spam@please.net> wrote:
On 21/7/19 9:56 am, Piotr Wyderski wrote:
John Larkin wrote:
I get to teach a young engineer my Dremeling secrets.
I am not able to produce decent PCBs that way, but ...
I grew up using a dental drill we had at home, so I'm ok freehand, but...
I've set a Dremel drill press up with the minimum bit height just at the
bottom of the copper. It's trivial to slide the PCB under it in nice
straight lines, but it really needs two hands. I'm considering attaching
a foot pedal to the lever that drops the bit down, to free the second
hand. It would be trivial to achieve results better than John's
freehand, that way.
Clifford Heath.
The copper carving is artistic but fundamentally insignificant. The
"results" that matter are the circuit performance.
Yes, and really straight cuts (without needing a lot of practise) would
help with that.
make a simple pantograph, stylus sets the cutting depth and it would be
easy to follow a straight edge to do lines
Have you done that?
mandag den 22. juli 2019 kl. 09.27.07 UTC+2 skrev Clifford Heath:
On 22/7/19 1:13 pm, John Larkin wrote:
On Mon, 22 Jul 2019 11:15:57 +1000, Clifford Heath
no.spam@please.net> wrote:
On 21/7/19 9:56 am, Piotr Wyderski wrote:
John Larkin wrote:
I get to teach a young engineer my Dremeling secrets.
I am not able to produce decent PCBs that way, but ...
I grew up using a dental drill we had at home, so I'm ok freehand, but...
I've set a Dremel drill press up with the minimum bit height just at the
bottom of the copper. It's trivial to slide the PCB under it in nice
straight lines, but it really needs two hands. I'm considering attaching
a foot pedal to the lever that drops the bit down, to free the second
hand. It would be trivial to achieve results better than John's
freehand, that way.
Clifford Heath.
The copper carving is artistic but fundamentally insignificant. The
"results" that matter are the circuit performance.
Yes, and really straight cuts (without needing a lot of practise) would
help with that.
make a simple pantograph, stylus sets the cutting depth and it would be
easy to follow a straight edge to do lines
Steve Wilson <no@spam.com> wrote:
On Mon, 22 Jul 2019 13:39:06 GMT, Steve Wilson <no@spam.com> wrote:
Do not chop the copper, especially for high speed circuits.
Carving the topside copper is the best way to do really fast stuff. It
allows one to run a 50 ohm coplanar waveguide into an edge-launch SMA.
So? You can do the same on a small pcb, then mount it on a larger ground
plane to put the following circuitry.
You are not going to do really fast sstuff on FR4. You need Rogers or
similar, which is very expensive to put on a pcb. So use a small piece
of Rogers for the fast stuff, and a larger copperclad for the supporting
circuits.
In fact, you showed the results of mixing Rogers or similar with FR4. The
boards warped into a bowl. You posted a multimegabyte video showing the bowl
rotating forever.
Now you don't have to do that. Keep the really fast stuff on a small pcb, and
the surrounding circuity on copperclad. You can work on each one separately
and don't have to wait until one is finished before starting on the other.
Save time and money.
John Larkin <jjlarkin@highlandtechnology.com> wrote:
On Mon, 22 Jul 2019 13:39:06 GMT, Steve Wilson <no@spam.com> wrote:
Do not chop the copper, especially for high speed circuits.
Carving the topside copper is the best way to do really fast stuff. It
allows one to run a 50 ohm coplanar waveguide into an edge-launch SMA.
So? You can do the same on a small pcb, then mount it on a larger ground
plane to put the following circuitry.
You are not going to do really fast sstuff on FR4. You need Rogers or
similar, which is very expensive to put on a pcb. So use a small piece of
Rogers for the fast stuff, and a larger copperclad for the supporting
circuits.
On Thu, 18 Jul 2019 12:39:33 -0700, John Larkin wrote:
We need 28 volts p-p at 14 MHz to test our IQ modulator box. I've
bought two Chinese RF amps from Amazon and both are garbage. So we're
going to build our own class C amp, as a dremel'd prototype.
https://www.dropbox.com/s/tq8qsvc7lbfirmh/Z468_WB_1.png?raw=1
I get to teach a young engineer my Dremeling secrets.
Here's one way we could do it.
https://www.dropbox.com/s/aga3fq00n0g5b3y/28S772A1.pdf?raw=1
The T577 is my little totem-pole ganfet switch board.
If we lay this out to fit into one of our standard enclosures, we
could call it a product. The output filter could be a bandpass for the
sine generator function, or a lowpass, or nothing, for a pulse output.
Input could be AC or DC coupled, and there are lots of possibilities
for the power and amplitude programming bits.
I might add a crystal oscillator just for fun. Digikey will program an
XO to basically any frequency one wants.
This one only needs 3 mA of supply current:
https://www.digikey.com/product-detail/en/epson/SG-8018CA-TJHPA/SG-8018CA-TJHPA-ND/7784056
I would be linear regulating from up to 56 volts!
On Mon, 22 Jul 2019 17:27:01 +1000, Clifford Heath
no.spam@please.net> wrote:
On 22/7/19 1:13 pm, John Larkin wrote:
On Mon, 22 Jul 2019 11:15:57 +1000, Clifford Heath
no.spam@please.net> wrote:
On 21/7/19 9:56 am, Piotr Wyderski wrote:
John Larkin wrote:
I get to teach a young engineer my Dremeling secrets.
I am not able to produce decent PCBs that way, but ...
I grew up using a dental drill we had at home, so I'm ok freehand, but...
I've set a Dremel drill press up with the minimum bit height just at the
bottom of the copper. It's trivial to slide the PCB under it in nice
straight lines, but it really needs two hands. I'm considering attaching
a foot pedal to the lever that drops the bit down, to free the second
hand. It would be trivial to achieve results better than John's
freehand, that way.
Clifford Heath.
The copper carving is artistic but fundamentally insignificant. The
"results" that matter are the circuit performance.
Yes, and really straight cuts (without needing a lot of practise) would
help with that.
How?
The thing I like about freehand Dremeling is that all I need is the
Dremel, and it's really fast, and I can add cuts after parts are
soldered down and things are all wired up on my bench. I do need to
remember to switch power off.
mandag den 22. juli 2019 kl. 21.59.15 UTC+2 skrev John Larkin:
On Mon, 22 Jul 2019 05:34:50 -0700 (PDT), Lasse Langwadt Christensen
langwadt@fonz.dk> wrote:
mandag den 22. juli 2019 kl. 09.27.07 UTC+2 skrev Clifford Heath:
On 22/7/19 1:13 pm, John Larkin wrote:
On Mon, 22 Jul 2019 11:15:57 +1000, Clifford Heath
no.spam@please.net> wrote:
On 21/7/19 9:56 am, Piotr Wyderski wrote:
John Larkin wrote:
I get to teach a young engineer my Dremeling secrets.
I am not able to produce decent PCBs that way, but ...
I grew up using a dental drill we had at home, so I'm ok freehand, but...
I've set a Dremel drill press up with the minimum bit height just at the
bottom of the copper. It's trivial to slide the PCB under it in nice
straight lines, but it really needs two hands. I'm considering attaching
a foot pedal to the lever that drops the bit down, to free the second
hand. It would be trivial to achieve results better than John's
freehand, that way.
Clifford Heath.
The copper carving is artistic but fundamentally insignificant. The
"results" that matter are the circuit performance.
Yes, and really straight cuts (without needing a lot of practise) would
help with that.
make a simple pantograph, stylus sets the cutting depth and it would be
easy to follow a straight edge to do lines
Have you done that?
I have CNC'ed some
https://www.dropbox.com/s/sd5glp85699nhun/P1000046.JPG?dl=0
https://www.dropbox.com/s/yaq9m62cmdmjxtt/P1000063.JPG?dl=0
but I could see a pantograph work maybe even with some templates
for common packages
like this, if it wasn't so silly expensive
https://www.amazon.com/Proxxon-27106-PROXXON-Engraving-Device/dp/B00JVSZXF4
On Mon, 22 Jul 2019 19:26:16 GMT, Steve Wilson <no@spam.com> wrote:
Steve Wilson <no@spam.com> wrote:
On Mon, 22 Jul 2019 13:39:06 GMT, Steve Wilson <no@spam.com> wrote:
Do not chop the copper, especially for high speed circuits.
Carving the topside copper is the best way to do really fast stuff.
It allows one to run a 50 ohm coplanar waveguide into an edge-launch
SMA.
So? You can do the same on a small pcb, then mount it on a larger
ground plane to put the following circuitry.
You are not going to do really fast sstuff on FR4. You need Rogers or
similar, which is very expensive to put on a pcb. So use a small piece
of Rogers for the fast stuff, and a larger copperclad for the
supporting circuits.
In fact, you showed the results of mixing Rogers or similar with FR4.
The boards warped into a bowl. You posted a multimegabyte video showing
the bowl rotating forever.
Now you don't have to do that. Keep the really fast stuff on a small
pcb, and the surrounding circuity on copperclad. You can work on each
one separately and don't have to wait until one is finished before
starting on the other. Save time and money.
Got examples?
On Mon, 22 Jul 2019 19:18:32 GMT, Steve Wilson <no@spam.com> wrote:
You are not going to do really fast sstuff on FR4. You need Rogers or
similar, which is very expensive to put on a pcb. So use a small piece of
Rogers for the fast stuff, and a larger copperclad for the supporting
circuits.
I do picosecond stuff on FR4, both dremel'd and then as multilayer
PCBs.
On Sunday, July 21, 2019 at 4:01:38 PM UTC-4, John Larkin wrote:
On Thu, 18 Jul 2019 12:39:33 -0700, John Larkin wrote:
We need 28 volts p-p at 14 MHz to test our IQ modulator box. I've
bought two Chinese RF amps from Amazon and both are garbage. So we're
going to build our own class C amp, as a dremel'd prototype.
https://www.dropbox.com/s/tq8qsvc7lbfirmh/Z468_WB_1.png?raw=1
I get to teach a young engineer my Dremeling secrets.
Here's one way we could do it.
https://www.dropbox.com/s/aga3fq00n0g5b3y/28S772A1.pdf?raw=1
The T577 is my little totem-pole ganfet switch board.
If we lay this out to fit into one of our standard enclosures, we
could call it a product. The output filter could be a bandpass for the
sine generator function, or a lowpass, or nothing, for a pulse output.
Input could be AC or DC coupled, and there are lots of possibilities
for the power and amplitude programming bits.
I might add a crystal oscillator just for fun. Digikey will program an
XO to basically any frequency one wants.
This one only needs 3 mA of supply current:
https://www.digikey.com/product-detail/en/epson/SG-8018CA-TJHPA/SG-8018CA-TJHPA-ND/7784056
I would be linear regulating from up to 56 volts!
Those programmable oscillators are square wave output. 14MHz is a stock frequency at Digikey, and can be bought for as little as 16 cents each, per 1000.
https://www.digikey.com/products/en/crystals-oscillators-resonators/crystals/171?k=crystal&k=&pkeyword=crystal&sv=0&pv2150=u14MHz&sf=1&FV=ffe000ab&quantity=&ColumnSort=0&page=1&pageSize=25
https://www.digikey.com/product-detail/en/txc-corporation/9B14000025/9B14000025-ND/5955066
You can use the crystals to generate tthe signal, as well as to clean it up with a crystal filter.