B
bitrex
Guest
On 11/8/19 6:45 PM, bitrex wrote:
Generally by playing stairway to heaven as the test case
Generally by playing stairway to heaven as the test case
B
bitrex
Guest
On 11/8/19 4:44 PM, piglet wrote:
Usually we test to see if the amp is working by plugging the guitar in,
turning the volume up and seeing if it makes sound
Usually we test to see if the amp is working by plugging the guitar in,
turning the volume up and seeing if it makes sound
P
Phil Allison
Guest
Lasse Langwadt Christensen wrote:
-------------------------------------
** There are no guitar cables on that list.
Guitarist buy ready made, 5m &r 7m leads in packets from retail stores.
Most of them from China.
Not 100m reels of expensive cable that exists only on maker's web pages.
You tedious wog wanker.
..... Phil
-------------------------------------
** There are no guitar cables on that list.
Guitarist buy ready made, 5m &r 7m leads in packets from retail stores.
Most of them from China.
Not 100m reels of expensive cable that exists only on maker's web pages.
You tedious wog wanker.
..... Phil
D
dcaster@krl.org
Guest
On Wednesday, November 6, 2019 at 6:41:36 PM UTC-5, TheExperimenter wrote:.
Skin resistance can vary from person to person.
When i was a freshman at college I participated in a psych study. It involved getting shocked when a certain sized object was shown and measuring skin resistance when other objects were shown.
Anyway the researcher set the variable transformer to a low voltage connected my arm to the transformer and applied power. Asked me if I felt a shock. I did not feel anything. So he raised the voltage and asked again. And] kept repeating until I felt a mild tickle. He tried to go thru his test, but the skin resistance kept drifting up and researcher got concerned at how high the voltage had to be to get a little response. Apparently my skin resistance was 5 or more times higher than his previous subjects.
Dan
Skin resistance can vary from person to person.
When i was a freshman at college I participated in a psych study. It involved getting shocked when a certain sized object was shown and measuring skin resistance when other objects were shown.
Anyway the researcher set the variable transformer to a low voltage connected my arm to the transformer and applied power. Asked me if I felt a shock. I did not feel anything. So he raised the voltage and asked again. And] kept repeating until I felt a mild tickle. He tried to go thru his test, but the skin resistance kept drifting up and researcher got concerned at how high the voltage had to be to get a little response. Apparently my skin resistance was 5 or more times higher than his previous subjects.
Dan
J
John Doe
Guest
TheExperimenter <theexp8712@noaol.net> wrote:
There is also much false advertising coming out of China that has been
OBVIOUS for years. Unfortunately nothing has been done about it.
There is also much false advertising coming out of China that has been
OBVIOUS for years. Unfortunately nothing has been done about it.
P
Phil Allison
Guest
Chris wrote:
** Might it be a Proton AM30 or similar ??
https://archiwum.allegro.pl/oferta/integrated-amplifier-proton-am-30-2x80w-better-nad-i7105457465.html
Lotsa weight on LH side, 80wpc, all black, simple, very good specs and almost a top name brand.
...... Phil
** Might it be a Proton AM30 or similar ??
https://archiwum.allegro.pl/oferta/integrated-amplifier-proton-am-30-2x80w-better-nad-i7105457465.html
Lotsa weight on LH side, 80wpc, all black, simple, very good specs and almost a top name brand.
...... Phil
P
Phil Allison
Guest
Martin Riddle wrote:
---------------------
** Yeah: DC300As, D150 IIs, D75s, Microtechs, Macrotechs, PAS2 self analysing amps, M600s and others.
Saw a few of them across my bench, mostly PSA2s
The later Crown K1 and K2 class D amps get my vote however.
Totally sealed case, no fan and hard to tell they were class D by external testing. Exceptionally reliable.
..... Phil
---------------------
** Yeah: DC300As, D150 IIs, D75s, Microtechs, Macrotechs, PAS2 self analysing amps, M600s and others.
Saw a few of them across my bench, mostly PSA2s
The later Crown K1 and K2 class D amps get my vote however.
Totally sealed case, no fan and hard to tell they were class D by external testing. Exceptionally reliable.
..... Phil
K
Klaus Kragelund
Guest
Can you link to a description of your system?
J
Jim Horton
Guest
On 11/12/19 7:03 PM, Klaus Kragelund wrote:
Sure. At first I constructed this:
https://www.youtube.com/watch?v=034F2JKX1Rs
Then modified the fan in the cover to include a non-functional one to
contain activated charcoal like this:
https://www.youtube.com/watch?v=WFSoNxbCb-c
The only other change was that I taped on a 5 foot piece of aluminum
dryer duct to make the unit more versatile. It will pull in smoke out
to about 6" and I can just move the ducting near the circuit avoiding
having to have the entire unit within range. Be sure the ducting is
sealed up against the plastic container. Aluminum tape worked fine.
Good luck! I should have built one of these years ago.
Sure. At first I constructed this:
https://www.youtube.com/watch?v=034F2JKX1Rs
Then modified the fan in the cover to include a non-functional one to
contain activated charcoal like this:
https://www.youtube.com/watch?v=WFSoNxbCb-c
The only other change was that I taped on a 5 foot piece of aluminum
dryer duct to make the unit more versatile. It will pull in smoke out
to about 6" and I can just move the ducting near the circuit avoiding
having to have the entire unit within range. Be sure the ducting is
sealed up against the plastic container. Aluminum tape worked fine.
Good luck! I should have built one of these years ago.
M
mpm
Guest
On Saturday, November 9, 2019 at 4:51:35 AM UTC-5, Chris wrote:
Carver?
TEAC?
Onkyo?
Ring any bells...?
Carver?
TEAC?
Onkyo?
Ring any bells...?
C
Chris
Guest
On Wed, 13 Nov 2019 18:37:49 -0800, mpm wrote:
None of them. The only one that does is JVC - but I've never really
considered them seriously as hi-fi amp manufacturers. Maybe I've
misjudged them.
None of them. The only one that does is JVC - but I've never really
considered them seriously as hi-fi amp manufacturers. Maybe I've
misjudged them.
J
John Doe
Guest
Doing some serious hard drugs...
--
bitrex <user example.net> wrote:
--
bitrex <user example.net> wrote:
Guest
> Folks have had success using a car battery for spot welding...Use the
starter solenoid and a push button and heavy copper lugs for the welding
points.
You can also use battery packs itself to spot weld additional one. Start with some spring mounted cells, than build it up.
I am testing my 2 Kw 18650 packs on my Leaf now. Went a little farter than before. Paid $6 for 8 KWh rip-off at Delano Evgo. 5 miles from the next town. Sitting outside a farm for level 1. The guy is nice enough to let me charge; so, I don't need to set up my solar charger.
starter solenoid and a push button and heavy copper lugs for the welding
points.
You can also use battery packs itself to spot weld additional one. Start with some spring mounted cells, than build it up.
I am testing my 2 Kw 18650 packs on my Leaf now. Went a little farter than before. Paid $6 for 8 KWh rip-off at Delano Evgo. 5 miles from the next town. Sitting outside a farm for level 1. The guy is nice enough to let me charge; so, I don't need to set up my solar charger.
J
John Robertson
Guest
On 2020/01/05 2:34 p.m., edward.ming.lee@gmail.com wrote:
Gas powered, eh?
(sorry, couldn't resist).
John ;-#)#
Gas powered, eh?
(sorry, couldn't resist).
John ;-#)#
P
Phil Hobbs
Guest
On 2020-01-05 14:38, jlarkin@highlandsniptechnology.com wrote:
that sort of thing. That way it looks like we knew what we were doing.
I use a fair number of zero-ohm jumpers for that. They also help during
bringup, especially the ones in series with the supplies.
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
It's always worthwhile to put in a bit of belt-and-suspenders when doing
that sort of thing. That way it looks like we knew what we were doing.
I use a fair number of zero-ohm jumpers for that. They also help during
bringup, especially the ones in series with the supplies.
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
Guest
Folks have had success using a car battery for spot welding...Use the
Sorry, no gas, went further than before.
Sorry, no gas, went further than before.
P
Phil Hobbs
Guest
On 2020-01-05 12:37, jlarkin@highlandsniptechnology.com wrote:
I didn't know about the built-in regulator--all the MMICs in my drawer
are the older kind that need a resistor. It's mostly the internal
matching, if any, that screws me up.
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
On Sun, 5 Jan 2020 11:33:41 +0100, Gerhard Hoffmann <dk4xp@arcor.de
wrote:
Am 03.01.20 um 20:50 schrieb John Larkin:
MMIC Zin is usually around 30 ohms at lowish frequency,
IIRC.
I measured GAV-63+ at about 90! And that goes up if I AC short
the output.
Sounds fishy. Maybe I should measure it different ways.
Here's a TDR/TDT of the GVA-63.
https://www.dropbox.com/s/cqdgynqisi6mlza/GVA-63_TDR_2.jpg?raw=1
The slow slope on the TDR is the DC block cap into the MMIC. I
can't account for the slow slope on the TDT, lower trace.
Looks like Zin is about 75 ohms. It goes up radically as device
current goes down below 60 mA. That suggests some serious
nonlinearities with a resistive bias source.
I did not have a GVA-63 here, only its grandpa, an ERA-2SM. So on
this rainy Saturday, I did paint a wideband amplifier, printed it
to foil, etched the board (with some other test structures) drilled
the vias to GND 0.3mm, soldered the GND connections with wrapping
wire and populated the board.
https://www.flickr.com/photos/137684711@N07/49332583887/in/album-72157662535945536/
is the circuit, next picture to the right is the layout, and then
the board.
Sorry for the soldering, these cell phone macro photos are so
unforgiving. Probably it's a good thing that they don't let me
solder space flight boards, I must call the qualified solder ladies
for every change.
Next picture is mag_db(S21), aka gain in blue and the input
impedance in Ohms (red). It seems that in the left half of the
plot, where the ERA2sm still works, the input impedance wiggles
around 50 Ohms. The network analyzer calculates Zin from the
measured S11.
The next picture is S11, and every curl is a resonance. It is more
than probable that the ERA-2 is not the guilty party, apart of its
input capacitance. As short as the input microstrip is, just
holding the hand over it without touching has visible influence.
The last picture is the Agilent 54754A TDR. The outer side of the
board's SMA barrel is exactly in the middle of the screen. The
ringing just left of the middle is the port saver.
The strip lines have been calculated for 0.8 mm FR4, but I only had
0.5mm thin FR4 left over, so the line impedance will be somewhat
low. A 200 mV step may be a little bit too much for a chip with
gain that lives on 3.5V.
Have a nice Sunday, Gerhard
Nice work. Your S11 and TDR are inconsistent with what I'm seeing on
the GVA part.
I woke up at 3AM [1] with a revelation, which may actually be true.
There are two common MMIC types around:
1) One of them is the classic Darlington, like ERA-x. It needs a
resistor from Vcc to the output pin to set the operating current. My
experience is that they behave as expected, with the low-frequency
response limited by the external coupling caps. Your TDR does
suggest a Zin below 50 ohms.
2) The newer type, like the GVA-63, includes some sort of current
regulating circuit, which allows a hard DC supply to be applied to
the output pin through an inductor. I conjecture that this current
regulator is slow, so it affects the low frequency gain and
impedances. That aligns with Phil's observation that MMICS have bad
low-frequency gain, which I thought strange because I hadn't seen
that before.
I didn't know about the built-in regulator--all the MMICs in my drawer
are the older kind that need a resistor. It's mostly the internal
matching, if any, that screws me up.
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
R
Rick C
Guest
On Sunday, January 5, 2020 at 5:22:11 PM UTC-5, John Doe wrote:
Just the opposite. A number of companies have considered battery swapping and all have given up. It is not an inherently fast operation even if it is faster than charging. It requires significant manual labor, even if just helping you get your car in position and is fraught with issues. Tesla had a pilot program as recently as 2016, but has been permanently closed.
The idea of changing out 1 of 4 batteries is pointless and offers no real benefit, just much more frequent stops.
People really do make a big deal out of the charging when it is just not such a big deal. Most people park at home all night with the car plugged in. The leave in the morning with a nearly full tank of electrons and return at home plugging in the car again for another charge. Later, rinse, repeat and they never even need to look at the gauge or stop at another gas station again... unless they really want crappy food in a smelly location.
--
Rick C.
++-+ Get 1,000 miles of free Supercharging
++-+ Tesla referral code - https://ts.la/richard11209
Just the opposite. A number of companies have considered battery swapping and all have given up. It is not an inherently fast operation even if it is faster than charging. It requires significant manual labor, even if just helping you get your car in position and is fraught with issues. Tesla had a pilot program as recently as 2016, but has been permanently closed.
The idea of changing out 1 of 4 batteries is pointless and offers no real benefit, just much more frequent stops.
People really do make a big deal out of the charging when it is just not such a big deal. Most people park at home all night with the car plugged in. The leave in the morning with a nearly full tank of electrons and return at home plugging in the car again for another charge. Later, rinse, repeat and they never even need to look at the gauge or stop at another gas station again... unless they really want crappy food in a smelly location.
--
Rick C.
++-+ Get 1,000 miles of free Supercharging
++-+ Tesla referral code - https://ts.la/richard11209
P
Phil Hobbs
Guest
On 2020-01-05 13:54, whit3rd wrote:
Depends on the mechanism. Being able to control the phase of the
coupling between the two transistors could turn out super useful.
I have some of those nice BLM15BA0050SN1 beads on order--check out the
Z(f) curve here:
<https://www.murata.com/en-us/products/productdetail?partno=BLM15BA050SN1%23>
They're still pretty reactive up to ~700 MHz, but they're awesome above
that.
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
Depends on the mechanism. Being able to control the phase of the
coupling between the two transistors could turn out super useful.
I have some of those nice BLM15BA0050SN1 beads on order--check out the
Z(f) curve here:
<https://www.murata.com/en-us/products/productdetail?partno=BLM15BA050SN1%23>
They're still pretty reactive up to ~700 MHz, but they're awesome above
that.
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
B
Bill Sloman
Guest
On Monday, January 6, 2020 at 5:02:09 AM UTC+11, Cursitor Doom wrote:
NT makes the same kind of claim. Every now and again a health guru goes to prison because somebody dies after taking their advice rather than going to somebody with proper medical training.
Giving people advice when you don't know what you are talking about is a dangerous habit - anything beyond "you should talk about that with the your doctor" is decidedly unwise.
> What have YOU got to show for the time you have spent helping others? (which I'm guessing is precisely nil).
Absolutely nothing, which follows the New Testament advice (Matthew 6.1) not that I expect to be rewarded in Heaven, since I don't think that there is one.
I don't make a habit of seeking out other people to help, but I do help other people from time to time, and don't make a fuss about it.
Your guess about how I might spend my time is a malicious speculation, and not the first you've come up with. You do come across as a nasty piece of work.
--
Bill Sloman, Sydney
NT makes the same kind of claim. Every now and again a health guru goes to prison because somebody dies after taking their advice rather than going to somebody with proper medical training.
Giving people advice when you don't know what you are talking about is a dangerous habit - anything beyond "you should talk about that with the your doctor" is decidedly unwise.
> What have YOU got to show for the time you have spent helping others? (which I'm guessing is precisely nil).
Absolutely nothing, which follows the New Testament advice (Matthew 6.1) not that I expect to be rewarded in Heaven, since I don't think that there is one.
I don't make a habit of seeking out other people to help, but I do help other people from time to time, and don't make a fuss about it.
Your guess about how I might spend my time is a malicious speculation, and not the first you've come up with. You do come across as a nasty piece of work.
--
Bill Sloman, Sydney