Re: Use SBM-20, Si-3B High Range Tubes in CDV-700 Probe Housing.
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Re: Use SBM-20, Si-3B High Range Tubes in CDV-700 Probe Housing.
For proof-of-concept the project was started with tried-and-true circuits that we have used before, but these were installed into either the CDV-700 body or in a Pikes Peak Prospector housing along with an Si-8b pancake. Their size was too large to actually fit into the CDV-700 Hot-dog probe housing but has always worked fine in home made plumbing pipe housings. 
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Use SBM-20, Si-3B High Range Tubes in CDV-700 Probe Housing.
This little project led to a plug in adaptor that fits the 3 Pin 6993 socket on one end and has a clip on the other end to accept a Russian tube. The wiring board first adapts the normal CDV-700 HV down to 450 for proper operation of the Russian tubes,? The board is long enough to hold the Si-3BG high range tube with no modifications. If the SBM-20 is desired, the end cap on the CDV-700 housing is removed and a shop made extension added. Works great, I have a .mov made but need to convert it into something the U-Tube understands. More pictures follow. Geo 
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Re: Question and an interesting site for those that modify CDV700s and more.
----- Original Message ----- From: Roger Whatley <rogwhat53@...> To: [email protected]Sent: Thu, 31 Mar 2022 10:33:18 -0400 (EDT) Subject: Re: [CDV700CLUB] Question and an interesting site for those that modify CDV700s and more.
OK. My only other suggestion is increasing the
zener voltage, such that the reference voltage becomes larger
compared to circuit errors. Then, when the [744K trimmer]
resistor between Q2 and ground gets larger to bring the current
back down, the 66M resistors also get smaller still, as less
multiplication of reference voltage is required. Less
multiplication means smaller circuit error in the output.
The dominant circuit errors are (mindsim
conclusions. :-)
1) delta-Vbe between Q1 and Q2 due to
generally different bias currents, and,
2) loop gain error in the feedback regulation.
If the multiplication ratio is lowered, the loop gain improves
by that ratio. This is then lowering loop gain error by the same
ratio.
I might assume you have a convenient reason
for sticking with a 5.1V Zener, but if you put two in series, or
use a 20V zener, you will get better regulation with less
circuit error.
rogerw
On 3/30/2022 11:29 PM, peter via
groups.io wrote:
Roger:
?Yup increasing the dropper resistor from 1M to 2.2 or 3.3M would
improve the shunt regulator's performance, but some of my
scintillator probes have low impedance resistor divider networks ~
10M( and hermetically sealed shut)
So I can't tolerate a 2 ~ 3M dropper unless the power supply has
sufficient head room. On the other hand, its not likely that I
would use? a power hungry probe that often.?
May be? I will migrate to a 2.2 or 3.3M dropper in the future. I
got to experiment more. Not really a logical reason but I
typically like to leave most of my stuff set to about 900V even if
they are adjustable.
Some probes are significantly more sensitive than others? so I can
drop the HV to use those probes. Next time I have my CDV-700 6a
open I will check the HV. I actually have two 6a's, one has the
original Victoreen?
regulator tube and the other has a zener string. If either is way
off from 900V, I will like to put this circuit inside.I could also
embedded this circuit into a cable.
P
--
rogerw
On the Catclaw
ΜΟΛΩΝ ΛΑΒΕ
The PanDemic is over, but the DemPanic goes on.
MisDisMal is a dictator's tool of repression.
|
Re: Question and an interesting site for those that modify CDV700s and more.
1) Yes. Unfortunately, delta-Vbe also has a positive temperature
coefficient, and this is present as an error voltage between Q1
and Q2 due to non-matching bias currents depending on (UnRegHV-
RegHV)/1Meg variation.
Another way to do this is to eliminate Q2 and connect the base of
Q1 directly to the resistor string. Then the effective reference
voltage is Vz + Vbe1, and Vbe1 has a negative tempco of -
2mV/degC. So, choosing the zener for +2mV/degC with Q2 removed
would result in zero tempco overall for the reference..... Might
be an improvement, but definitely a simplification!
Try the enclosed circuit..... all you need to do in your
breadboard is to short Q2's collector to emitter nodes. Then tweak
the trimmer to around 900K.....
2) btw simulated voltage regulation is poor IMHO because loop
gain is too low.
Best way to increase loop gain regulation in this simple circuit
is increasing the feedback ratio, ie, (744K/(744K + 66M 1+66m)
gets larger. Larger Vz and smaller multiplication does that.
rogerw
On 3/31/2022 10:25 AM, peter via
groups.io wrote:
Roger:
?
1) Something to check if stability isn't good enough. I guess I
can glue the transistors together if necessary too.
2) well higher and lower voltage zeners from 5.1~5.6V have
temperature coeffiecents. Around 5.1 is most stable.
? ? ?Can lookin into increasing the zener voltage
3) due to? my boo-boo, I thought I can compensate by adding some
feedback to make the regulation stiffer with respect to variation
in Vcc.
? ? Added a resistor in the bias network. See attachment. BTW my
sim didn't have a 2SK3563 so I used a 2SK311
P
--
rogerw
On the Catclaw
ΜΟΛΩΝ ΛΑΒΕ
The PanDemic is over, but the DemPanic goes on.
MisDisMal is a dictator's tool of repression.
|
Re: Question and an interesting site for those that modify CDV700s and more.
Roger:
?
1) Something to check if stability isn't good enough. I guess I can glue the transistors together if necessary too.
2) well higher and lower voltage zeners from 5.1~5.6V have temperature coeffiecents. Around 5.1 is most stable.
? ? ?Can lookin into increasing the zener voltage
3) due to? my boo-boo, I thought I can compensate by adding some feedback to make the regulation stiffer with respect to variation in Vcc.
? ? Added a resistor in the bias network. See attachment. BTW my sim didn't have a 2SK3563 so I used a 2SK311
P
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Re: Question and an interesting site for those that modify CDV700s and more.
OK.
My only other suggestion is increasing the
zener voltage, such that the reference voltage becomes larger
compared to circuit errors. Then, when the [744K trimmer]
resistor between Q2 and ground gets larger to bring the current
back down, the 66M resistors also get smaller still, as less
multiplication of reference voltage is required. Less
multiplication means smaller circuit error in the output.
The dominant circuit errors are (mindsim
conclusions. :-)
1) delta-Vbe between Q1 and Q2 due to
generally different bias currents, and,
2) loop gain error in the feedback regulation.
If the multiplication ratio is lowered, the loop gain improves
by that ratio. This is then lowering loop gain error by the same
ratio.
I might assume you have a convenient reason
for sticking with a 5.1V Zener, but if you put two in series, or
use a 20V zener, you will get better regulation with less
circuit error.
rogerw
On 3/30/2022 11:29 PM, peter via
groups.io wrote:
Roger:
?Yup increasing the dropper resistor from 1M to 2.2 or 3.3M would
improve the shunt regulator's performance, but some of my
scintillator probes have low impedance resistor divider networks ~
10M( and hermetically sealed shut)
So I can't tolerate a 2 ~ 3M dropper unless the power supply has
sufficient head room. On the other hand, its not likely that I
would use? a power hungry probe that often.?
May be? I will migrate to a 2.2 or 3.3M dropper in the future. I
got to experiment more. Not really a logical reason but I
typically like to leave most of my stuff set to about 900V even if
they are adjustable.
Some probes are significantly more sensitive than others? so I can
drop the HV to use those probes. Next time I have my CDV-700 6a
open I will check the HV. I actually have two 6a's, one has the
original Victoreen?
regulator tube and the other has a zener string. If either is way
off from 900V, I will like to put this circuit inside.I could also
embedded this circuit into a cable.
P
--
rogerw
On the Catclaw
ΜΟΛΩΝ ΛΑΒΕ
The PanDemic is over, but the DemPanic goes on.
MisDisMal is a dictator's tool of repression.
|
Re: Question and an interesting site for those that modify CDV700s and more.
Wow, good info.? Thanks.
-Chris
toggle quoted message
Show quoted text
Chris
section 9 of the proposal has a fixed price of $630,000 for the final release survey (8 week effort)
bid shows the decontamination will be done in parallel with final release survey :: "Therefore, only the incremental costs
associated with decontamination activities will apply." and they documented the breakdown of T&M costs.?
The cleanup cost would be added to the $630,000 survey cost ; would think it would push final cost? to $1M or more. Would need the final billing to know. More than double the cost of done today.
The
dollar had an average inflation rate of 2.38% per year between 1992 and today, producing a cumulative price increase of 102.22%. (CPI Inflation Calculator)
mje
On 3/27/2022 5:52 AM, C.R. wrote:
Wow, interesting stuff. ?Good job sleuthing it out. ?Sounds like CWM Nuclear had some extensive decontamination experience. ?Since that proposal was from 1992, I wonder if it was completed before later transactions of ownership(?) ?I would say probably...
since Victoreen "vacated" in 1994. ?I wonder how much it cost to do that cleanup.? However, I did not spend a lot of time looking for a price quote. ?
Interesting details (poorly OCR cut and pasted)
"contaminants of the Victoreen Project are Ni-63 (a very weak beta emitter), Cl-36 (strong beta emitter), and Ra-226 (strong gamma emitter). . A cost-effective approach to -Detection of the Ra-226 and Cl-36 is clearly straightforward. However, surveys
and decontamination detection of such a weak emitter requires sensitive instrumentation utilized by experienced personnel. Clearly, the ORAU verification survey- A reputation with USNRC for team is knowledgeable and experienced in working with such low-energy
accuracy, compliance, and isotopes and will be especially comprehensive in ensuring residual safety contamination has been removed."??
and...
"Victoreen vacated its Woodland Avenue space in 1994. The property was transferred to Kordi, Inc., and then to the Degeronimo family in 2000. It was foreclosed upon in April 2002 and then purchased by the Cathedral of Praise who began renovations to the
first floor of the building in June 2008. It had temporary electrical service installed in April 2009, but later in the year, Harper Industries was granted a demolition contract to raze the Victoreen complex. The buildings caught fire during the demolition
process in September 2014 and the project was abandoned.? As part of the Opportunity Corridor project, the long-abandoned and partially-demolished Victoreen Instrument factory was demolished in 2019."
-Chris
found a proposal for "decontamination and decommissioning services at former Victoreen Instrument building"
refers to:
"decontamination activities associated with both the lowenergy emitting nuclide (Ni-63) and high energy emitters (Ra 226, Cl-36) present at the Victorcen Project"
mje
On 3/25/2022 7:00 PM, C.R. wrote:
It's a grassy field now.? The land is for sale.? Might be able to walk around with a scintillator or sensitive enough counter and look for elevated levels from various things over the years. ?If I lived nearby, I would walk a perimeter by property line
boundaries to see if the cleanup missed anything that got tossed out back.? Maybe even just over the fence/off the property.??
Google maps:
Trashed location views before it got fully demolished: ?
I cannot find superfund cleanup records for it, but this is the address if someone else wants to try: 10101 Woodland Avenue, Cleveland, OH 44104
Attached is google map 3d rendered view of previous partial ruins...
-Chris
Speaking of Corotron HV regulator tubes, these were made by Victoreen, and maybe others, I don't know. When Victoreen ceased production some time ago, the plant where they were made was subject to a federal superfund type
environmental cleanup. Why? Because inside each Corotron tube there is a wire element that is covered in Ni-63 a radioactive element. The handling of Ni-63 had led to contamination in and around the plant, evidently nothing minor.
Right now I can't find the NRC report, but you and I (US Taxpayers) paid the bill one way or another.
If anyone has a reference to the document or the short article I wrote about it, please post it here.
Corotron gas filled? tubes (and there are other types, for example Neutron Detectors) operate in the corona portion of the Geiger/Proportional etc. discharge curve,?
Geo
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Re: Question and an interesting site for those that modify CDV700s and more.
Chris
section 9 of the proposal has a fixed price of $630,000 for the
final release survey (8 week effort)
bid shows the decontamination will be done in parallel with final
release survey :: "Therefore, only the incremental costs
associated with decontamination activities will apply." and they
documented the breakdown of T&M costs.?
The cleanup cost would be added to the $630,000 survey cost ;
would think it would push final cost? to $1M or more. Would need
the final billing to know. More than double the cost of done
today.
The dollar had an average inflation
rate of 2.38% per year between 1992 and today, producing a
cumulative price increase of 102.22%. (CPI Inflation Calculator)
mje
On 3/27/2022 5:52 AM, C.R. wrote:
toggle quoted message
Show quoted text
Wow, interesting stuff. ?Good job sleuthing it out. ?Sounds
like CWM Nuclear had some extensive decontamination experience.
?Since that proposal was from 1992, I wonder if it was completed
before later transactions of ownership(?) ?I would say
probably... since Victoreen "vacated" in 1994. ?I wonder how
much it cost to do that cleanup.? However, I did not spend a lot
of time looking for a price quote. ?
Interesting details (poorly OCR cut and pasted)
"contaminants of the Victoreen Project are Ni-63 (a very weak
beta emitter), Cl-36 (strong beta emitter), and Ra-226 (strong
gamma emitter). . A cost-effective approach to -Detection of the
Ra-226 and Cl-36 is clearly straightforward. However, surveys
and decontamination detection of such a weak emitter requires
sensitive instrumentation utilized by experienced personnel.
Clearly, the ORAU verification survey- A reputation with USNRC
for team is knowledgeable and experienced in working with such
low-energy accuracy, compliance, and isotopes and will be
especially comprehensive in ensuring residual safety
contamination has been removed."??
and...
"Victoreen vacated its Woodland Avenue space in 1994. The
property was transferred to Kordi, Inc., and then to the
Degeronimo family in 2000. It was foreclosed upon in April 2002
and then purchased by the Cathedral of Praise who began
renovations to the first floor of the building in June 2008. It
had temporary electrical service installed in April 2009, but
later in the year, Harper Industries was granted a demolition
contract to raze the Victoreen complex. The buildings caught
fire during the demolition process in September 2014 and the
project was abandoned.? As part of the Opportunity Corridor
project, the long-abandoned and partially-demolished Victoreen
Instrument factory was demolished in 2019."
-Chris
found a proposal
for "decontamination and decommissioning services at former
Victoreen Instrument building"
refers to:
"decontamination
activities associated with both the lowenergy emitting nuclide
(Ni-63) and high energy emitters (Ra 226, Cl-36) present at
the Victorcen Project"
mje
On 3/25/2022 7:00 PM, C.R. wrote:
It's a grassy field now.? The land is for sale.? Might be
able to walk around with a scintillator or sensitive enough
counter and look for elevated levels from various things
over the years. ?If I lived nearby, I would walk a perimeter
by property line boundaries to see if the cleanup missed
anything that got tossed out back.? Maybe even just over the
fence/off the property.??
Google maps:
Trashed location views before it got fully demolished: ?
I cannot find superfund cleanup records for it, but this
is the address if someone else wants to try: 10101 Woodland
Avenue, Cleveland, OH 44104
Attached is google map 3d rendered view of previous
partial ruins...
-Chris
Speaking of Corotron HV regulator tubes, these were made
by Victoreen, and maybe others, I don't know. When Victoreen
ceased production some time ago, the plant where they were
made was subject to a federal superfund type
environmental cleanup. Why? Because inside each Corotron
tube there is a wire element that is covered in Ni-63 a
radioactive element. The handling of Ni-63 had led to
contamination in and around the plant, evidently nothing
minor.
Right now I can't find the NRC report, but you and I (US
Taxpayers) paid the bill one way or another.
If anyone has a reference to the document or the short
article I wrote about it, please post it here.
Corotron gas filled? tubes (and there are other types, for
example Neutron Detectors) operate in the corona portion of
the Geiger/Proportional etc. discharge curve,?
Geo
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Re: Fun Identify the Probe QUIZ Clue 1
Thanks for checking in MikeL.
Geo
From: "Mike L." <loughlin3@...> To: "CDV700CLUB" < [email protected]> Sent: Thursday, March 31, 2022 5:49:17 AM Subject: Re: [CDV700CLUB] Fun Identify the Probe QUIZ Clue 1
[Edited Message Follows]
I knew this one, but M.K.? beat me to it. Mike L.
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Re: Fun Identify the Probe QUIZ Clue 1
I knew this one, but M.K.? beat me to it.
Mike L.
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Re: Question and an interesting site for those that modify CDV700s and more.
Cool Peter, thanks for that update.?
Been there, done that many times, just another part of the experimenting process, called "the smoke test".
Geo
From: "peter via groups.io" <epkoncept@...> To: "CDV700CLUB" < [email protected]> Sent: Wednesday, March 30, 2022 10:45:36 PM Subject: Re: [CDV700CLUB] Question and an interesting site for those that modify CDV700s and more.
Roger et al:
The weird voltage dropping trend as Vcc was raised well past the shunting knee point was my fault.
Yesterday, while tinkering I accidentally connected the resistor that is connected to the upper fet's gate and? to the dropper resistor had its upper lead connected to Vcc.
See the dotted line on the attached jpg.
I must have accidentally connected the upper 66M resistor to the wrong point while tinkering and didn't notice.
Sorry for the confusion. Circuit is operating as expected after reconnecting the resistor to the lower side of the 1M dropper resistor and seems to follow what Micro-Cap simulates.
P
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Re: Question and an interesting site for those that modify CDV700s and more.
Roger:
?Yup increasing the dropper resistor from 1M to 2.2 or 3.3M would improve the shunt regulator's performance, but some of my scintillator probes have low impedance resistor divider networks ~ 10M( and hermetically sealed shut)
So I can't tolerate a 2 ~ 3M dropper unless the power supply has sufficient head room. On the other hand, its not likely that I would use? a power hungry probe that often.?
May be? I will migrate to a 2.2 or 3.3M dropper in the future. I got to experiment more. Not really a logical reason but I typically like to leave most of my stuff set to about 900V even if they are adjustable.
Some probes are significantly more sensitive than others? so I can drop the HV to use those probes. Next time I have my CDV-700 6a open I will check the HV. I actually have two 6a's, one has the original Victoreen?
regulator tube and the other has a zener string. If either is way off from 900V, I will like to put this circuit inside.I could also embedded this circuit into a cable.
P
|
Re: Question and an interesting site for those that modify CDV700s and more.
good deal! All is well!
btw you might consider increasing that 1M
"dropper resistor" to 2M or 3M, I think regulation may improve
as it is increased.
rogerw
On 3/30/2022 10:45 PM, peter via
groups.io wrote:
Roger et al:
The weird voltage dropping trend as Vcc was raised well past the
shunting knee point was my fault.
Yesterday, while tinkering I accidentally connected the resistor
that is connected to the upper fet's gate and? to the dropper
resistor had its upper lead connected to Vcc.
See the dotted line on the attached jpg.
I must have accidentally connected the upper 66M resistor to the
wrong point while tinkering and didn't notice.
Sorry for the confusion. Circuit is operating as expected after
reconnecting the resistor to the lower side of the 1M dropper
resistor and seems to follow what Micro-Cap simulates.
P
--
rogerw
On the Catclaw
ΜΟΛΩΝ ΛΑΒΕ
The PanDemic is over, but the DemPanic goes on.
MisDisMal is a dictator's tool of repression.
|
Re: Question and an interesting site for those that modify CDV700s and more.
Roger et al:
The weird voltage dropping trend as Vcc was raised well past the shunting knee point was my fault.
Yesterday, while tinkering I accidentally connected the resistor that is connected to the upper fet's gate and? to the dropper resistor had its upper lead connected to Vcc.
See the dotted line on the attached jpg.
I must have accidentally connected the upper 66M resistor to the wrong point while tinkering and didn't notice.
Sorry for the confusion. Circuit is operating as expected after reconnecting the resistor to the lower side of the 1M dropper resistor and seems to follow what Micro-Cap simulates.
P
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Re: Question and an interesting site for those that modify CDV700s and more.
I ought to take back the second sentence of my
reply below:
"If it does not ask for that breakdown voltage
parameter, it is not there."
You could be using a specific model from a
model library in SPICE which does model the body diode and does
not ask you for that parameter because it was in the datasheet
for that device.
I am working up a LTSpice simulation, still
working on it.
rogerw
On 3/30/2022 6:59 PM, Roger Whatley via
groups.io wrote:
Only if the MosFet model being used
incorporates that feature. If it does not ask for that
breakdown voltage parameter, it is not there.
However you can add a discrete diode to the
simulation and specify its breakdown, perhaps? Or if you only
have off-the-shelf diode models can you pick one with a
suitably high breakdown? Maybe two or three in series?
Depends on what is in your model library.
rogerw
On 3/30/2022 5:52 PM, peter via
groups.io wrote:
roger:
?Newbie question. Do Spice simulators model the break down of
the body diode of MosFets ?
I looked at the model used in Micro-Cap 12 and I didn't see
any parameter that jumped out and indicated it was the body
diode ?
P
--
rogerw
On the Catclaw
ΜΟΛΩΝ ΛΑΒΕ
The PanDemic is over, but the DemPanic goes on.
MisDisMal is a dictator's tool of repression.
--
rogerw
On the Catclaw
ΜΟΛΩΝ ΛΑΒΕ
The PanDemic is over, but the DemPanic goes on.
MisDisMal is a dictator's tool of repression.
|
Re: Question and an interesting site for those that modify CDV700s and more.
Only if the MosFet model being used
incorporates that feature. If it does not ask for that breakdown
voltage parameter, it is not there.
However you can add a discrete diode to the
simulation and specify its breakdown, perhaps? Or if you only
have off-the-shelf diode models can you pick one with a suitably
high breakdown? Maybe two or three in series?
Depends on what is in your model library.
rogerw
On 3/30/2022 5:52 PM, peter via
groups.io wrote:
roger:
?Newbie question. Do Spice simulators model the break down of
the body diode of MosFets ?
I looked at the model used in Micro-Cap 12 and I didn't see any
parameter that jumped out and indicated it was the body diode ?
P
--
rogerw
On the Catclaw
ΜΟΛΩΝ ΛΑΒΕ
The PanDemic is over, but the DemPanic goes on.
MisDisMal is a dictator's tool of repression.
|
Re: Fun Identify the Probe QUIZ Clue 1
Good guess M.K., right out of the box!
Here's the?final Clue picture to show the unfamiliar the proportions of a '719
At the bottom of the photo notice the socket end of the CDV-700 probe housing, while the Beta Shield and rest of the top part of the housing is a far piece above it, at the end of the LND 179.
Geo
----- Original Message ----- From: M. K. <ka2mce@...> To: [email protected]Sent: Wed, 30 Mar 2022 19:15:47 -0400 (EDT) Subject: Re: [CDV700CLUB] Fun Identify the Probe QUIZ Clue 1
LND 719 perhaps(other companies have the same tube with different #'s though). Looks like a extra long 6993
It's a metal tube and has a 3 pin base that fits a CDV-700 probe socket?
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Re: Fun Identify the Probe QUIZ Clue 1
of course, you don't mention the length, so if it's short, then 6993(again, different companies have different #'s for this too)
On Wed, Mar 30, 2022 at 7:15 PM M. K. < ka2mce@...> wrote: LND 719 perhaps(other companies have the same tube with different #'s though). Looks like a extra long 6993
It's a metal tube and has a 3 pin base that fits a CDV-700 probe socket? 
|
Re: Fun Identify the Probe QUIZ Clue 1
LND 719 perhaps(other companies have the same tube with different #'s though). Looks like a extra long 6993
It's a metal tube and has a 3 pin base that fits a CDV-700 probe socket? 
|
Mike L.
