|
Sorry, this is long. Maybe you folks can help with our project, point us to sources of RF help, or at least help me find a scope. But because this is a scope forum I'll start with the scope part. I should add that a DSO would be nice, but an old fashioned CRT analog scope may be perfectly fine.
We need a scope to examine a waveform that we want to apply to a pair of electro-chemical cells wired in series. Currently we power the cells with 1.0 VDC, and they normally they draw between 3 and 5 A. It is thought that cell performance would improve if we can cause the chemicals in the cells to resonate, hence the desire to superimpose an AC signal on top of the DC. We have been able to explore frequencies up to 100 kHz for square waves and pulses and 300 kHz for sine waves, but not surprisingly those lowish frequencies did not help.
We now want to explore frequencies from about 1 MHz to as much as we can afford on a shoestring budget, but no less than 30 MHz for square waves and pulses and 50 MHz for sine waves. 100 MHz would be nice, but there's that budget issue.
The waveforms, at least initially, would be limited to 1 V maximum, and never going negative. We are thinking that the maximum AC amplitude would be 0.5 V peak, or 1.0 V peak to peak, and that would be superimposed on a 0.5 V DC bias voltage. A minimum AC amplitude would be 0.05 V peak, or 0.10 V peak to peak, and that would be superimposed on a 0.95 DC bias voltage.
We'd also like to monitor current if we can find a shunt that does not distort the waveform.
An issue is that I can't guarantee that the final wiring will give us a common ground point so we may need a scope and lead set up where can can measure two differential voltages. (Our Tek 222 with it's isolated inputs is nice in that regard, but at 10 MHz bandwidth won't work for these higher frequencies.)
So if you guys can point us in the right direction for what models of new or used scopes might work for us. Or even sell us one of your surplus working scopes.
Local Craiglist scopes available that appear to work from pics and description: (I know, buyer beware.)
Tek 2465 (not A or B) $350 firm. (Seems a little high)
Tek 2215A, $100 firm (Not quite enough bandwidth)
Tek TDS 3052B (No price given, and I don't know much about this other than labeled 500 MHz)
Anritsu MS2711D (I know nothing about this brand or model)
We're also going to need an arbitrary waveform generator, and the "superimposed RF on top of DC" power supply. These could be the subject of another posting if there's any interest, or we could keep those non scope subjects off forum.
If it makes any difference, our 3 person start up is in Seaford, Delaware.
|
Look for a 475. 250 MHz BW and usually under $200. Less if you care to
learn how to repair the known issues (capacitors).
?
This is an excellent general purpose scope.
?
?
Regards,
Tom
?
toggle quoted message
Show quoted text
----- Original Message -----
Sent: Friday, January 04, 2013 11:34
AM
Subject: [TekScopes] Need help choosing a
scope and some other RF capable equipment.
?
Sorry, this is long. Maybe you folks can help with our project, point us to
sources of RF help, or at least help me find a scope. But because this is a
scope forum I'll start with the scope part. I should add that a DSO would be
nice, but an old fashioned CRT analog scope may be perfectly fine.
We
need a scope to examine a waveform that we want to apply to a pair of
electro-chemical cells wired in series. Currently we power the cells with 1.0
VDC, and they normally they draw between 3 and 5 A. It is thought that cell
performance would improve if we can cause the chemicals in the cells to
resonate, hence the desire to superimpose an AC signal on top of the DC. We
have been able to explore frequencies up to 100 kHz for square waves and
pulses and 300 kHz for sine waves, but not surprisingly those lowish
frequencies did not help.
We now want to explore frequencies from
about 1 MHz to as much as we can afford on a shoestring budget, but no less
than 30 MHz for square waves and pulses and 50 MHz for sine waves. 100 MHz
would be nice, but there's that budget issue.
The waveforms, at least
initially, would be limited to 1 V maximum, and never going negative. We are
thinking that the maximum AC amplitude would be 0.5 V peak, or 1.0 V peak to
peak, and that would be superimposed on a 0.5 V DC bias voltage. A minimum AC
amplitude would be 0.05 V peak, or 0.10 V peak to peak, and that would be
superimposed on a 0.95 DC bias voltage.
We'd also like to monitor
current if we can find a shunt that does not distort the waveform.
An
issue is that I can't guarantee that the final wiring will give us a common
ground point so we may need a scope and lead set up where can can measure two
differential voltages. (Our Tek 222 with it's isolated inputs is nice in that
regard, but at 10 MHz bandwidth won't work for these higher
frequencies.)
So if you guys can point us in the right direction for
what models of new or used scopes might work for us. Or even sell us one of
your surplus working scopes.
Local Craiglist scopes available that
appear to work from pics and description: (I know, buyer beware.)
Tek
2465 (not A or B) $350 firm. (Seems a little high)
Tek 2215A, $100 firm
(Not quite enough bandwidth)
Tek TDS 3052B (No price given, and I don't
know much about this other than labeled 500 MHz)
Anritsu MS2711D (I know
nothing about this brand or model)
We're also going to need an
arbitrary waveform generator, and the "superimposed RF on top of DC" power
supply. These could be the subject of another posting if there's any interest,
or we could keep those non scope subjects off forum.
If it makes any
difference, our 3 person start up is in Seaford, Delaware.
|
Hi,
Sounds like Hybrid battery work. There are several nice 475s on ebay. Just search for tektronix 475. If you like, I have a 3 channel 7704A on ebay. See item 290839243077. It should serve well and other options can be added.
Jerry Massengale
toggle quoted message
Show quoted text
-----Original Message-----
From: sknaugler
To: TekScopes
Sent: Fri, Jan 4, 2013 10:34 am
Subject: [TekScopes] Need help choosing a scope and some other RF capable equipment.
?
Sorry, this is long. Maybe you folks can help with our project, point us to sources of RF help, or at least help me find a scope. But because this is a scope forum I'll start with the scope part. I should add that a DSO would be nice, but an old fashioned CRT analog scope may be perfectly fine.
We need a scope to examine a waveform that we want to apply to a pair of electro-chemical cells wired in series. Currently we power the cells with 1.0 VDC, and they normally they draw between 3 and 5 A. It is thought that cell performance would improve if we can cause the chemicals in the cells to resonate, hence the desire to superimpose an AC signal on top of the DC. We have been able to explore frequencies up to 100 kHz for square waves and pulses and 300 kHz for sine waves, but not surprisingly those lowish frequencies did not help.
We now want to explore frequencies from about 1 MHz to as much as we can afford on a shoestring budget, but no less than 30 MHz for square waves and pulses and 50 MHz for sine waves. 100 MHz would be nice, but there's that budget issue.
The waveforms, at least initially, would be limited to 1 V maximum, and never going negative. We are thinking that the maximum AC amplitude would be 0.5 V peak, or 1.0 V peak to peak, and that would be superimposed on a 0.5 V DC bias voltage. A minimum AC amplitude would be 0.05 V peak, or 0.10 V peak to peak, and that would be superimposed on a 0.95 DC bias voltage.
We'd also like to monitor current if we can find a shunt that does not distort the waveform.
An issue is that I can't guarantee that the final wiring will give us a common ground point so we may need a scope and lead set up where can can measure two differential voltages. (Our Tek 222 with it's isolated inputs is nice in that regard, but at 10 MHz bandwidth won't work for these higher frequencies.)
So if you guys can point us in the right direction for what models of new or used scopes might work for us. Or even sell us one of your surplus working scopes.
Local Craiglist scopes available that appear to work from pics and description: (I know, buyer beware.)
Tek 2465 (not A or B) $350 firm. (Seems a little high)
Tek 2215A, $100 firm (Not quite enough bandwidth)
Tek TDS 3052B (No price given, and I don't know much about this other than labeled 500 MHz)
Anritsu MS2711D (I know nothing about this brand or model)
We're also going to need an arbitrary waveform generator, and the "superimposed RF on top of DC" power supply. These could be the subject of another posting if there's any interest, or we could keep those non scope subjects off forum.
If it makes any difference, our 3 person start up is in Seaford, Delaware.
|
Hi Jerry,
No, not Hybrid battery work. We're developing an electro-chemical compressor for refrigeration use. We have a web site that needs redoing, but there's a bit about us on www.xergyinc.com
Unless any of these scopes have fully isolated inputs, like our 222 with non removable leads, or the Fluke Scopemeters, I think we want a four channel scope with two pairs of channels to be configured as two differential inputs.
Your 7704A might be suitable if the 7A19 module could be swapped for a second 7A26, assuming the mainframe will accept such a combination. (Now I've got some reading to do.)
I assume you mean a plain old 475, not the TAS 475. Although the TAS 475 (100 MHz) and the TAS 485 (200 MHz) are four channel scopes, so seem interesting.
Maybe someone can chime in on TAS reliability, repairability, and their ability to be configured for differential inputs.
Steve N
toggle quoted message
Show quoted text
Hi,
Sounds like Hybrid battery work. There are several nice 475s on ebay. Just search for tektronix 475. If you like, I have a 3 channel 7704A on ebay. See item 290839243077. It should serve well and other options can be added.
Jerry Massengale
|
Hi Tom,
Like Jerry you suggested a 475. The only issue I have with a 475 is the fact that it's a two channel scope that does not have isolated inputs, although that can be fixed with the right lead assemblies. (I may not really mean leads. External isolating hardware of some sort where I don't know the right lingo.)
If I choose to only monitor the waveform voltage a two channel scope set up for differential measurements is fine. If I try to measure current (voltage across a shunt) I'll need a second two channels set up for differential voltage measurements.
And I prefer not to do this with two scopes. I like to overlay the waveforms and look for phase changes between the voltage and current.
So the 475 is still a good candidate if I choose to forgo monitoring current.
Thanks,
Steve N.
toggle quoted message
Show quoted text
--- In TekScopes@..., "Tom Miller" wrote:
Look for a 475. 250 MHz BW and usually under $200. Less if you care to learn how to repair the known issues (capacitors).
This is an excellent general purpose scope.
Regards,
Tom
|
Hi Steve,
?
Then most definitely you should?take a look at Jerry's 7704A. It can
take any number of different plug in vertical modules including differential
input types. You could use one for the current and a two channel standard for
the single ended stuff.
?
BTW, I can attest to the quality of Jerry's work. He stands behind the
equipment and there is no risk of getting a "powers up" unit from the bey.
?
Good luck,
Tom
?
toggle quoted message
Show quoted text
----- Original Message -----
Sent: Friday, January 04, 2013 2:54
PM
Subject: [TekScopes] Re: Need help
choosing a scope and some other RF capable equipment.
?
Hi Tom,
Like Jerry you suggested a 475. The only issue I
have with a 475 is the fact that it's a two channel scope that does not have
isolated inputs, although that can be fixed with the right lead assemblies. (I
may not really mean leads. External isolating hardware of some sort where I
don't know the right lingo.)
If I choose to only monitor the waveform
voltage a two channel scope set up for differential measurements is fine. If I
try to measure current (voltage across a shunt) I'll need a second two
channels set up for differential voltage measurements.
And I prefer not
to do this with two scopes. I like to overlay the waveforms and look for phase
changes between the voltage and current.
So the 475 is still a good
candidate if I choose to forgo monitoring current.
Thanks,
Steve
N.
--- In TekScopes@..., "Tom
Miller" wrote:
>
> Look for a 475. 250 MHz BW and usually under
$200. Less if you care to learn how to repair the known issues
(capacitors).
>
> This is an excellent general purpose
scope.
>
>
> Regards,
> Tom
|
Sounds more like cold fusion (or worse)! How could chemicals resonate?
toggle quoted message
Show quoted text
On Fri, Jan 4, 2013 at 11:03 AM, jerry massengale <j_massengale@...> wrote: Sounds like Hybrid battery work. There are several nice 475s on ebay. Just search for tektronix 475. If you like, I have a 3 channel 7704A on ebay. See item 290839243077. It should serve well and other options can be added.
|
No, nothing as impossible or profitable as cold fusion.? We're developing an electro-chemical compressor for refrigeration use, and there is water in our cells by design. "Bound water and ice have critical frequencies (??S) at about 10 MHz"
The above quote is from:? http://www.lsbu.ac.uk/water/microwave.html We believe the water in our cells ins "bound" and not free, hence our desire for a DC biased RF power supply, but we need to test this.? We really hope that the water is not free because we really don't want to deal with DC biased microwave power supplies. Steve N --- In TekScopes@..., David DiGiacomo wrote: > > Sounds more like cold fusion (or worse)! How could chemicals resonate?
|
Hi Jerry,
??? ??? ??? ??? Nice looking scope, too far away for me. However,
you've listed it as a 200 MHz scope in the title but only 100 MHz in
the description. I guess I could look it up but which is correct? I
suspect 200 MHz.
Don Black.
On 05-Jan-13 5:03 AM, jerry massengale wrote:
toggle quoted message
Show quoted text
?
Hi,
Sounds like Hybrid
battery work. There are several nice
475s on ebay. Just search for tektronix 475. If
you like, I have a 3 channel 7704A on ebay. See item 290839243077.
It should serve well and other
options can be added.
Jerry Massengale
-----Original Message-----
From: sknaugler
To: TekScopes
Sent: Fri, Jan 4, 2013 10:34 am
Subject: [TekScopes] Need help choosing a scope and
some other RF capable equipment.
?
Sorry, this is long. Maybe you folks
can help with our project, point us to
sources of RF help, or at least help me
find a scope. But because this is a scope
forum I'll start with the scope part. I
should add that a DSO would be nice, but
an old fashioned CRT analog scope may be
perfectly fine.
We need a scope to examine a waveform that
we want to apply to a pair of
electro-chemical cells wired in series.
Currently we power the cells with 1.0 VDC,
and they normally they draw between 3 and
5 A. It is thought that cell performance
would improve if we can cause the
chemicals in the cells to resonate, hence
the desire to superimpose an AC signal on
top of the DC. We have been able to
explore frequencies up to 100 kHz for
square waves and pulses and 300 kHz for
sine waves, but not surprisingly those
lowish frequencies did not help.
We now want to explore frequencies from
about 1 MHz to as much as we can afford on
a shoestring budget, but no less than 30
MHz for square waves and pulses and 50 MHz
for sine waves. 100 MHz would be nice, but
there's that budget issue.
The waveforms, at least initially, would
be limited to 1 V maximum, and never going
negative. We are thinking that the maximum
AC amplitude would be 0.5 V peak, or 1.0 V
peak to peak, and that would be
superimposed on a 0.5 V DC bias voltage. A
minimum AC amplitude would be 0.05 V peak,
or 0.10 V peak to peak, and that would be
superimposed on a 0.95 DC bias voltage.
We'd also like to monitor current if we
can find a shunt that does not distort the
waveform.
An issue is that I can't guarantee that
the final wiring will give us a common
ground point so we may need a scope and
lead set up where can can measure two
differential voltages. (Our Tek 222 with
it's isolated inputs is nice in that
regard, but at 10 MHz bandwidth won't work
for these higher frequencies.)
So if you guys can point us in the right
direction for what models of new or used
scopes might work for us. Or even sell us
one of your surplus working scopes.
Local Craiglist scopes available that
appear to work from pics and description:
(I know, buyer beware.)
Tek 2465 (not A or B) $350 firm. (Seems a
little high)
Tek 2215A, $100 firm (Not quite enough
bandwidth)
Tek TDS 3052B (No price given, and I don't
know much about this other than labeled
500 MHz)
Anritsu MS2711D (I know nothing about this
brand or model)
We're also going to need an arbitrary
waveform generator, and the "superimposed
RF on top of DC" power supply. These could
be the subject of another posting if
there's any interest, or we could keep
those non scope subjects off forum.
If it makes any difference, our 3 person
start up is in Seaford, Delaware.
|
Chemicals can resonate no worse than Power/Ground plane on a multilayer
board, as claimed by famous Howard Johnson of 'Black Magic' fame.
A bit off subject, but close enough to cold fusion.
Miroslav Pokorni
On 1/4/2013 12:40 PM, David DiGiacomo wrote:
toggle quoted message
Show quoted text
?
Sounds more like cold fusion (or worse)! How could chemicals
resonate?
On Fri, Jan 4, 2013 at 11:03 AM, jerry massengale j_massengale@...>
wrote:
> Sounds like Hybrid battery work. There are several nice 475s on
ebay. Just search for tektronix 475. If you like, I have a 3 channel
7704A on ebay. See item 290839243077. It should serve well and other
options can be added.
|
Hey, don't get in the way of research! ?:)
Either they achieve the results they seek, or they don't. ?It should never be our place to discourage pure research, nor to blindly challenge their postulates.
History teaches us the unfortunate lessons and fates of people who believed that a flat Earth was the center of the Universe.
73 Jim N6OTQ
From: Miroslav Pokorni
To: TekScopes@...
Cc: David DiGiacomo
Sent: Friday, January 4, 2013 4:11 PM
Subject: Re: [TekScopes] Need help choosing a scope and some other RF capable equipment.
Chemicals can resonate no worse than Power/Ground plane on a multilayer
board, as claimed by famous Howard Johnson of 'Black Magic' fame.
A bit off subject, but close enough to cold fusion.
Miroslav Pokorni
On 1/4/2013 12:40 PM, David DiGiacomo wrote:
?
Sounds more like cold fusion (or worse)! How could chemicals
resonate?
On Fri, Jan 4, 2013 at 11:03 AM, jerry massengale j_massengale@...>
wrote:
> Sounds like Hybrid battery work. There are several nice 475s on
ebay. Just search for tektronix 475. If you like, I have a 3 channel
7704A on ebay. See item 290839243077. It should serve well and other
options can be added.
|
You mean it really isn't flat???
Don Black.
On 05-Jan-13 9:24 AM, Jim wrote:
toggle quoted message
Show quoted text
?
History
teaches us the unfortunate lessons and fates of people
who believed that a flat Earth was the center of the
Universe.
73
Jim
N6OTQ
|
Thanks Don,
Yes it is 200MHZ. I will see if I can fix the listing. Where are you?
Jerry Massengale
toggle quoted message
Show quoted text
-----Original Message-----
From: Don Black
To: TekScopes
Sent: Fri, Jan 4, 2013 4:08 pm
Subject: Re: [TekScopes] Need help choosing a scope and some other RF capable equipment.
?
Hi Jerry,
??? ??? ??? ??? Nice looking scope, too far away for me. However,
you've listed it as a 200 MHz scope in the title but only 100 MHz in
the description. I guess I could look it up but which is correct? I
suspect 200 MHz.
Don Black.
On 05-Jan-13 5:03 AM, jerry massengale wrote:
?
Hi,
Sounds like Hybrid
battery work. There are several nice
475s on ebay. Just search for tektronix 475. If
you like, I have a 3 channel 7704A on ebay. See item 290839243077.
It should serve well and other
options can be added.
Jerry Massengale
-----Original Message-----
From: sknaugler
To: TekScopes
Sent: Fri, Jan 4, 2013 10:34 am
Subject: [TekScopes] Need help choosing a scope and
some other RF capable equipment.
?
Sorry, this is long. Maybe you folks
can help with our project, point us to
sources of RF help, or at least help me
find a scope. But because this is a scope
forum I'll start with the scope part. I
should add that a DSO would be nice, but
an old fashioned CRT analog scope may be
perfectly fine.
We need a scope to examine a waveform that
we want to apply to a pair of
electro-chemical cells wired in series.
Currently we power the cells with 1.0 VDC,
and they normally they draw between 3 and
5 A. It is thought that cell performance
would improve if we can cause the
chemicals in the cells to resonate, hence
the desire to superimpose an AC signal on
top of the DC. We have been able to
explore frequencies up to 100 kHz for
square waves and pulses and 300 kHz for
sine waves, but not surprisingly those
lowish frequencies did not help.
We now want to explore frequencies from
about 1 MHz to as much as we can afford on
a shoestring budget, but no less than 30
MHz for square waves and pulses and 50 MHz
for sine waves. 100 MHz would be nice, but
there's that budget issue.
The waveforms, at least initially, would
be limited to 1 V maximum, and never going
negative. We are thinking that the maximum
AC amplitude would be 0.5 V peak, or 1.0 V
peak to peak, and that would be
superimposed on a 0.5 V DC bias voltage. A
minimum AC amplitude would be 0.05 V peak,
or 0.10 V peak to peak, and that would be
superimposed on a 0.95 DC bias voltage.
We'd also like to monitor current if we
can find a shunt that does not distort the
waveform.
An issue is that I can't guarantee that
the final wiring will give us a common
ground point so we may need a scope and
lead set up where can can measure two
differential voltages. (Our Tek 222 with
it's isolated inputs is nice in that
regard, but at 10 MHz bandwidth won't work
for these higher frequencies.)
So if you guys can point us in the right
direction for what models of new or used
scopes might work for us. Or even sell us
one of your surplus working scopes.
Local Craiglist scopes available that
appear to work from pics and description:
(I know, buyer beware.)
Tek 2465 (not A or B) $350 firm. (Seems a
little high)
Tek 2215A, $100 firm (Not quite enough
bandwidth)
Tek TDS 3052B (No price given, and I don't
know much about this other than labeled
500 MHz)
Anritsu MS2711D (I know nothing about this
brand or model)
We're also going to need an arbitrary
waveform generator, and the "superimposed
RF on top of DC" power supply. These could
be the subject of another posting if
there's any interest, or we could keep
those non scope subjects off forum.
If it makes any difference, our 3 person
start up is in Seaford, Delaware.
|
Hi jerry,
??? ??? ????? I'm in Australia, shipping costs here would be much
more than the scope. It looks like a nice package, I'm sure it will
sell.
I always enjoy your posts to the group, usually learn something from
them.
Don Black.
On 05-Jan-13 10:24 AM, jerry massengale wrote:
toggle quoted message
Show quoted text
?
Thanks Don,
Yes it is 200MHZ. I will see if I can
fix the listing. Where are you?
Jerry Massengale
-----Original
Message-----
From: Don Black
To: TekScopes
Sent: Fri, Jan 4, 2013 4:08 pm
Subject: Re: [TekScopes] Need help choosing a scope
and some other RF capable equipment.
?
Hi Jerry,
??? ??? ??? ??? Nice looking scope, too
far away for me. However, you've listed it
as a 200 MHz scope in the title but only
100 MHz in the description. I guess I
could look it up but which is correct? I
suspect 200 MHz.
Don Black.
On 05-Jan-13 5:03 AM, jerry massengale
wrote:
?
Hi,
Sounds like Hybrid battery work. There are
several nice 475s on ebay.
Just search for tektronix 475.
If you like, I have a 3
channel 7704A on ebay. See item 290839243077.
It should serve
well and other options can
be added.
Jerry Massengale
-----Original
Message-----
From: sknaugler
To: TekScopes
Sent: Fri, Jan 4, 2013 10:34 am
Subject: [TekScopes] Need help
choosing a scope and some other RF
capable equipment.
?
Sorry, this is long.
Maybe you folks can help
with our project, point us
to sources of RF help, or at
least help me find a scope.
But because this is a scope
forum I'll start with the
scope part. I should add
that a DSO would be nice,
but an old fashioned CRT
analog scope may be
perfectly fine.
We need a scope to examine a
waveform that we want to
apply to a pair of
electro-chemical cells wired
in series. Currently we
power the cells with 1.0
VDC, and they normally they
draw between 3 and 5 A. It
is thought that cell
performance would improve if
we can cause the chemicals
in the cells to resonate,
hence the desire to
superimpose an AC signal on
top of the DC. We have been
able to explore frequencies
up to 100 kHz for square
waves and pulses and 300 kHz
for sine waves, but not
surprisingly those lowish
frequencies did not help.
We now want to explore
frequencies from about 1 MHz
to as much as we can afford
on a shoestring budget, but
no less than 30 MHz for
square waves and pulses and
50 MHz for sine waves. 100
MHz would be nice, but
there's that budget issue.
The waveforms, at least
initially, would be limited
to 1 V maximum, and never
going negative. We are
thinking that the maximum AC
amplitude would be 0.5 V
peak, or 1.0 V peak to peak,
and that would be
superimposed on a 0.5 V DC
bias voltage. A minimum AC
amplitude would be 0.05 V
peak, or 0.10 V peak to
peak, and that would be
superimposed on a 0.95 DC
bias voltage.
We'd also like to monitor
current if we can find a
shunt that does not distort
the waveform.
An issue is that I can't
guarantee that the final
wiring will give us a common
ground point so we may need
a scope and lead set up
where can can measure two
differential voltages. (Our
Tek 222 with it's isolated
inputs is nice in that
regard, but at 10 MHz
bandwidth won't work for
these higher frequencies.)
So if you guys can point us
in the right direction for
what models of new or used
scopes might work for us. Or
even sell us one of your
surplus working scopes.
Local Craiglist scopes
available that appear to
work from pics and
description: (I know, buyer
beware.)
Tek 2465 (not A or B) $350
firm. (Seems a little high)
Tek 2215A, $100 firm (Not
quite enough bandwidth)
Tek TDS 3052B (No price
given, and I don't know much
about this other than
labeled 500 MHz)
Anritsu MS2711D (I know
nothing about this brand or
model)
We're also going to need an
arbitrary waveform
generator, and the
"superimposed RF on top of
DC" power supply. These
could be the subject of
another posting if there's
any interest, or we could
keep those non scope
subjects off forum.
If it makes any difference,
our 3 person start up is in
Seaford, Delaware.
|
"Bound water and ice have critical frequencies (??S) at about 10 MHz"
The above quote is from: That is not resonance. We believe the water in our cells ins "bound" and not free, hence our desire for a DC biased RF power supply, but we need to test this. We really hope that the water is not free because we really don't want to deal with DC biased microwave power supplies. A bias tee is not a big deal.
|
Only Kansas and my high-school girlfriends are flat.
:)
73 Jim N6OTQ
From: Don Black
To: TekScopes@...
Sent: Friday, January 4, 2013 4:58 PM
Subject: Re: [TekScopes] Need help choosing a scope and some other RF capable equipment.
You mean it really isn't flat???
Don Black.
On 05-Jan-13 9:24 AM, Jim wrote:
?
History
teaches us the unfortunate lessons and fates of people
who believed that a flat Earth was the center of the
Universe.
73
Jim
N6OTQ
|
David,
A bias tee isn't a big deal at all, but injecting the properly biased RF voltage with the DC and RF currents at workable voltages/currents might be.
I
think it's an interesting project, from a standpoint of "how do we do this" -- based on their three-person, self-funded, bootstrapped startup paradigm.
Even if the project fails, helping develop the technology might be fun for many of us.
From my computer? ?This looks like as
interesting a challenge as helping the neighbor across the backyard fence rebuild his fence to keep his daughter's pit bulldog confined -- neighbor knew less than nothing about fence-building, but we shared a common vision.
We succeeded, and we accomplished our shared vision of fixing the fence to keep that G%^&D*(%%$(&^)* mutt confined.
I would hope that all of us would see this particular project from the same standpoint -- achieve success, or at least experience failure at the peak of our shared technical abilities. ?
I hesitate to list my projects that I've started but that failed on the first endeavor. ? Most of you should have a similar record of failure -- if you don't, then you're not looking high enough nor reaching far enough.
73 Jim N6OTQ
From: David DiGiacomo
To: TekScopes@...
Sent: Friday, January 4, 2013 5:49 PM
Subject: Re: [TekScopes] Re: Need help choosing a scope and some other RF capable equipment. A bias tee is not a big deal.
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Hi Don,
I really enjoy the group. Thanks.
Jerry Massengale
toggle quoted message
Show quoted text
-----Original Message-----
From: Don Black
To: TekScopes
Sent: Fri, Jan 4, 2013 5:33 pm
Subject: Re: [TekScopes] Need help choosing a scope and some other RF capable equipment.
?
Hi jerry,
??? ??? ????? I'm in Australia, shipping costs here would be much
more than the scope. It looks like a nice package, I'm sure it will
sell.
I always enjoy your posts to the group, usually learn something from
them.
Don Black.
On 05-Jan-13 10:24 AM, jerry massengale wrote:
?
Thanks Don,
Yes it is 200MHZ. I will see if I can
fix the listing. Where are you?
Jerry Massengale
-----Original
Message-----
From: Don Black
To: TekScopes
Sent: Fri, Jan 4, 2013 4:08 pm
Subject: Re: [TekScopes] Need help choosing a scope
and some other RF capable equipment.
?
Hi Jerry,
??? ??? ??? ??? Nice looking scope, too
far away for me. However, you've listed it
as a 200 MHz scope in the title but only
100 MHz in the description. I guess I
could look it up but which is correct? I
suspect 200 MHz.
Don Black.
On 05-Jan-13 5:03 AM, jerry massengale
wrote:
?
Hi,
Sounds like Hybrid battery work. There are
several nice 475s on ebay.
Just search for tektronix 475.
If you like, I have a 3
channel 7704A on ebay. See item 290839243077.
It should serve
well and other options can
be added.
Jerry Massengale
-----Original
Message-----
From: sknaugler
To: TekScopes
Sent: Fri, Jan 4, 2013 10:34 am
Subject: [TekScopes] Need help
choosing a scope and some other RF
capable equipment.
?
Sorry, this is long.
Maybe you folks can help
with our project, point us
to sources of RF help, or at
least help me find a scope.
But because this is a scope
forum I'll start with the
scope part. I should add
that a DSO would be nice,
but an old fashioned CRT
analog scope may be
perfectly fine.
We need a scope to examine a
waveform that we want to
apply to a pair of
electro-chemical cells wired
in series. Currently we
power the cells with 1.0
VDC, and they normally they
draw between 3 and 5 A. It
is thought that cell
performance would improve if
we can cause the chemicals
in the cells to resonate,
hence the desire to
superimpose an AC signal on
top of the DC. We have been
able to explore frequencies
up to 100 kHz for square
waves and pulses and 300 kHz
for sine waves, but not
surprisingly those lowish
frequencies did not help.
We now want to explore
frequencies from about 1 MHz
to as much as we can afford
on a shoestring budget, but
no less than 30 MHz for
square waves and pulses and
50 MHz for sine waves. 100
MHz would be nice, but
there's that budget issue.
The waveforms, at least
initially, would be limited
to 1 V maximum, and never
going negative. We are
thinking that the maximum AC
amplitude would be 0.5 V
peak, or 1.0 V peak to peak,
and that would be
superimposed on a 0.5 V DC
bias voltage. A minimum AC
amplitude would be 0.05 V
peak, or 0.10 V peak to
peak, and that would be
superimposed on a 0.95 DC
bias voltage.
We'd also like to monitor
current if we can find a
shunt that does not distort
the waveform.
An issue is that I can't
guarantee that the final
wiring will give us a common
ground point so we may need
a scope and lead set up
where can can measure two
differential voltages. (Our
Tek 222 with it's isolated
inputs is nice in that
regard, but at 10 MHz
bandwidth won't work for
these higher frequencies.)
So if you guys can point us
in the right direction for
what models of new or used
scopes might work for us. Or
even sell us one of your
surplus working scopes.
Local Craiglist scopes
available that appear to
work from pics and
description: (I know, buyer
beware.)
Tek 2465 (not A or B) $350
firm. (Seems a little high)
Tek 2215A, $100 firm (Not
quite enough bandwidth)
Tek TDS 3052B (No price
given, and I don't know much
about this other than
labeled 500 MHz)
Anritsu MS2711D (I know
nothing about this brand or
model)
We're also going to need an
arbitrary waveform
generator, and the
"superimposed RF on top of
DC" power supply. These
could be the subject of
another posting if there's
any interest, or we could
keep those non scope
subjects off forum.
If it makes any difference,
our 3 person start up is in
Seaford, Delaware.
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"Bound water and ice have critical frequencies at about 10 MHz""That is not resonance."
Sorry for using the wrong terminology.? I am not an RF engineer.? I don't even play one on TV, but not through lack of auditioning. So of it is not resonance, what is the correct terminology?
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On Fri, Jan 4, 2013 at 8:12 PM, sknaugler <steven1955@...> wrote: "Bound water and ice have critical frequencies at about 10 MHz"
"That is not resonance."
Sorry for using the wrong terminology. I am not an RF engineer. I don't even play one on TV, but not through lack of auditioning.
So of it is not resonance, what is the correct terminology? What's wrong with calling it a critical frequency? The article says it's the frequency of maximum dielectric loss, which is kind of the opposite of resonance. Anyway, how does it help you? If you want to heat the water, you could do it just as well with a heating element.
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