got around to pulling the ENI I got off epay out of the box and checking it out.? A problem child - but it is an ENI.? Could use suggestions from the smart people in the room -? the ENI turns on but doesn't do anything. Turn it X10, the needle goes right to about 2 mR/s and sits there.? Turn it to X1, it goes full right.? You can move the needle around with the calibration knob on the ceramic component module (MOD A).? There is no sound. No clicky.? and no response to the check source. You just turn it on and the needle moves to position depending on the range setting.? ?From what I can tell, this ENI seems original - no evidence of any previous soldering.? ?
I suppose I should start with the basic checks outlined in the manual.??
|
Re: Need Help Modifying the Low Range Probe from AN/PDR-63
Geo Thanks for the info, it is good to know. I'll write separately to the other email address about other things. Steve
toggle quoted message
Show quoted text
------ Original Message ------
From: "Geo Dowell" <GEOelectronics@...>
To: "CDV700CLUB" <[email protected]>
Sent: Wednesday, 20 Apr, 22 At 12:39
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
The '63 is an interesting unit electronically speaking. The low range unit uses a 700V G-M tube, but on some ranges is operated below its Geiger region at 500 or 570V. Naturally it doesn't count at the HV. WHy do this? Because all G-M tubes are subject to "saturation" at high count rates.
What this term means is the tube is literally saturated with radiation coming in so fast, it loses the ability to reset itself between pulses, resulting in a ZERO reading, not good.
In practice this is observed when a user is walking or driving into a radiation filed with a G-M instrument, the readings will increase steadily then suddenly drop to zero! High end civilian meters have an alarm, the CDV-700 does not. In the instructions, the manuals always state that they are for training and in-shelter (low radiation fileds) testing of food and water supplies. We're all hobbyists here on this group (for now anyway).
Military recognized this that's why there's an ion-chamber unit in the '63 too, to cover those high radiation fields. Some other RADIACS, instead of an ion-chamber have a very small high-range GM tube piggy-backed onto the main probe body to handle the issue.
But in the '63 while the low range tube is connected, the higher ranges, way outside it's normal capability are access by reducing the DC voltage below the threshold of detection, then briefly pulsing an additional Voltage over the top of it to take a single measurement, knowing the tube may saturate, the pulse is very brief and turns itself off quickly, giving the G-M tube time to reset itself for the next pulse. In this way the G-M tube's upper limit of detection is greatly increased. But this is at a cost, since only a fraction of the radiation strikes are actually being reported.
Some civilian detection units operate with a similar system continuously, therefore their CPM are different from other units using the same tube.
Keep these facts in mind when seeing something being reported strictly in CPM.
Also ALWAYS, always, suspect ANY reports given in mR/Hr units form any instrument, unless all the other measuring parameters are listed as well. Many factors are responsible for correct mR/Hr readings.
Geo
From: "STEPHEN CARLILE via groups.io" <smcarlile@...> To: "CDV700CLUB" < [email protected]> Cc: "tanner carlile" < tanner.carlile@...> Sent: Wednesday, April 20, 2022 6:14:56 AM Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
Excellent! Thanks,
------ Original Message ------
From: "Geo Dowell" <GEOelectronics@...>
To: "CDV700CLUB" <[email protected]>
Sent: Wednesday, 20 Apr, 22 At 12:10
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
That's what I thought. When you or your son gets a chance, verify the tube # inside there. That is a great unit to adapt directly to the CDV-700, but is needs a HV adaptor, because the Geiger-Muller tube in it is a typical US military 700V tube. So conversion is to strip out all that is not associated with the long G-M tube and it's support, install the HV adaptor pcb in the probe body, convert to coax connector on the base of the probe. and it's ready for use on the CDV-700. Nothing need be done to the CDV-700. Alternatively a single HV adaptor mounted in a slender inline housing box could serve any number of 700V probes. Those end window probes are sensitive and rugged, as are all the RADIAC series housings, to be sure. Good project, thanks for posting it. Geo
From: "STEPHEN CARLILE via groups.io" <smcarlile@...> To: "CDV700CLUB" < [email protected]> Sent: Wednesday, April 20, 2022 5:45:43 AM Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63 
------ Original Message ------
From: "STEPHEN CARLILE via groups.io" <smcarlile@...>
To: [email protected]
Sent: Wednesday, 20 Apr, 22 At 11:23
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
George, Thanks very much. I have looked everywhere for this manual.. The probe is the Low Range Unit, DT-507/PDR-63 as described on page 5-11 and shown in figure 5-5 page 5-19. It goes thru a box with resistors to calibrate the pulses / voltage...as shown on pages 5-11, 5-12, and 5-13. Thanks, Steve
------ Original Message ------
From: "Geo Dowell" <GEOelectronics@...>
To: "CDV700CLUB" <[email protected]>
Sent: Wednesday, 20 Apr, 22 At 10:59
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
Start with this manual Steve, and identify the model # of the probe. Geo From: "smcarlile via groups.io" <smcarlile@...> To: "CDV700CLUB" < [email protected]> Sent: Wednesday, April 20, 2022 3:26:57 AM Subject: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63 Hello, I have a probe from a non-working AN/PDR-63 and want to modify it to fit on a CDV-700. I do not have the book so I cannot share the schematics. I'd appreciate guidance from anyone who has done this modification. In addition, I am trying to track down a copy of the manual so I can post the schematics. Thanks Steve
|
Re: Need Help Modifying the Low Range Probe from AN/PDR-63
The '63 is an interesting unit electronically speaking. The low range unit uses a 700V G-M tube, but on some ranges is operated below its Geiger region at 550 or 570V. Naturally it doesn't count at the HV. Why do this? Because all G-M tubes are subject to "saturation" at high count rates.
?
What this term means is the tube is literally saturated with radiation coming in so fast, it loses the ability to reset itself between pulses, resulting in a ZERO reading,/ not good.
?
In practice this is observed when a user is walking or driving into a radiation field with a G-M instrument, the readings will increase steadily then suddenly drop to zero! High end civilian meters have an alarm, the CDV-700 does not.? In the instructions, the manuals always state that they are for training and in-shelter (low radiation fields) testing of food and water supplies. We're all hobbyists here on this group (for now anyway).
?
Military recognized this, that's why there's an ion-chamber unit in the '63 too, to cover those high radiation fields. Some other? RADIACS, instead of an ion-chamber have a very small high-range GM tube piggy-backed onto the main probe body to handle the issue.
?
But in the '63 while the low range tube is connected, the higher ranges, way outside it's normal capability are access by reducing the DC? voltage below the threshold of detection, then briefly pulsing an additional Voltage over the top of it to take a single measurement, knowing the tube may saturate, the pulse is very brief and turns itself off quickly, giving the G-M tube time to reset itself for the next pulse. In this way the G-M tube's upper limit of detection is greatly increased. But this is at a cost, since only a fraction of the radiation strikes are actually being reported.
?
Some civilian detection units operate with a similar system continuously, therefore their CPM are different from other units using the same tube.
?
Keep these facts in mind when seeing something being reported strictly in CPM.
?
Also ALWAYS, always, suspect ANY reports given in mR/Hr units form any instrument, unless all the other measuring parameters are listed as well. Many factors are responsible for correct mR/Hr readings.
?
Geo
?
?
?
From: "STEPHEN CARLILE via groups.io" <smcarlile@...> To: "CDV700CLUB" < [email protected]> Cc: "tanner carlile" <tanner.carlile@...> Sent: Wednesday, April 20, 2022 6:14:56 AM Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
?
Excellent! Thanks,
?
------ Original Message ------
From: "Geo Dowell" <GEOelectronics@...>
To: "CDV700CLUB" <[email protected]>
Sent: Wednesday, 20 Apr, 22 At 12:10
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
That's what I thought.
When you or your son gets a chance, verify the tube # inside there.
That is a great unit to adapt directly to the CDV-700, but is needs a HV adaptor, because the Geiger-Muller tube in it is a typical US military 700V tube.
So conversion is to strip out all that is not associated with the long G-M tube and it's support, install the HV adaptor pcb in the probe body, convert to coax connector on the base of the probe. and it's ready for use on the CDV-700. Nothing need be done to the CDV-700.
Alternatively a single HV adaptor mounted in a slender inline housing box could serve any number of 700V probes.
Those end window probes are sensitive and rugged, as are all the RADIAC series housings, to be sure.
Good project, thanks for posting it.
Geo
From: "STEPHEN CARLILE via groups.io" <smcarlile@...> To: "CDV700CLUB" < [email protected]> Sent: Wednesday, April 20, 2022 5:45:43 AM Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
------ Original Message ------
From: "STEPHEN CARLILE via groups.io" <smcarlile@...>
To: [email protected]
Sent: Wednesday, 20 Apr, 22 At 11:23
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
George,
Thanks very much. I have looked everywhere for this manual..
The probe is the Low Range Unit, DT-507/PDR-63 as described on page 5-11 and shown in figure 5-5 page 5-19.
It goes thru a box with resistors to calibrate the pulses / voltage...as shown on pages 5-11, 5-12, and 5-13.
Thanks,
Steve
------ Original Message ------
From: "Geo Dowell" <GEOelectronics@...>
To: "CDV700CLUB" <[email protected]>
Sent: Wednesday, 20 Apr, 22 At 10:59
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
Start with this manual Steve, and identify the model # of the probe.
Geo
From: "smcarlile via groups.io" <smcarlile@...> To: "CDV700CLUB" < [email protected]> Sent: Wednesday, April 20, 2022 3:26:57 AM Subject: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
Hello, I have a probe from a non-working AN/PDR-63 and want to modify it to fit on a CDV-700. I do not have the book so I cannot share the schematics. I'd appreciate guidance from anyone who has done this modification. In addition, I am trying to track down a copy of the manual so I can post the schematics. Thanks Steve
|
Re: Need Help Modifying the Low Range Probe from AN/PDR-63
toggle quoted message
Show quoted text
------ Original Message ------
From: "Geo Dowell" <GEOelectronics@...>
To: "CDV700CLUB" <[email protected]>
Sent: Wednesday, 20 Apr, 22 At 12:10
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
That's what I thought.
When you or your son gets a chance, verify the tube # inside there.
That is a great unit to adapt directly to the CDV-700, but is needs a HV adaptor, because the Geiger-Muller tube in it is a typical US military 700V tube.
So conversion is to strip out all that is not associated with the long G-M tube and it's support, install the HV adaptor pcb in the probe body, convert to coax connector on the base of the probe. and it's ready for use on the CDV-700. Nothing need be done to the CDV-700.
Alternatively a single HV adaptor mounted in a slender inline housing box could serve any number of 700V probes.
Those end window probes are sensitive and rugged, as are all the RADIAC series housings, to be sure.
Good project, thanks for posting it.
Geo
From: "STEPHEN CARLILE via groups.io" <smcarlile@...> To: "CDV700CLUB" < [email protected]> Sent: Wednesday, April 20, 2022 5:45:43 AM Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
------ Original Message ------
From: "STEPHEN CARLILE via groups.io" <smcarlile@...>
To: [email protected]
Sent: Wednesday, 20 Apr, 22 At 11:23
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
George, Thanks very much. I have looked everywhere for this manual.. The probe is the Low Range Unit, DT-507/PDR-63 as described on page 5-11 and shown in figure 5-5 page 5-19. It goes thru a box with resistors to calibrate the pulses / voltage...as shown on pages 5-11, 5-12, and 5-13. Thanks, Steve
------ Original Message ------
From: "Geo Dowell" <GEOelectronics@...>
To: "CDV700CLUB" <[email protected]>
Sent: Wednesday, 20 Apr, 22 At 10:59
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
Start with this manual Steve, and identify the model # of the probe. Geo From: "smcarlile via groups.io" <smcarlile@...> To: "CDV700CLUB" < [email protected]> Sent: Wednesday, April 20, 2022 3:26:57 AM Subject: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63 Hello, I have a probe from a non-working AN/PDR-63 and want to modify it to fit on a CDV-700. I do not have the book so I cannot share the schematics. I'd appreciate guidance from anyone who has done this modification. In addition, I am trying to track down a copy of the manual so I can post the schematics. Thanks Steve
|
Re: Need Help Modifying the Low Range Probe from AN/PDR-63
That's what I thought.
When you or your son gets a chance, verify the tube # inside there.
That is a great unit to adapt directly to the CDV-700, but is needs a HV adaptor, because the Geiger-Muller tube in it is a typical US military 700V tube.
So conversion is to strip out all that is not associated with the long G-M tube and it's support, install the HV adaptor pcb in the probe body, convert to coax connector on the base of the probe. and it's ready for? use on the CDV-700. Nothing need be done to the CDV-700.
Alternatively a single HV adaptor mounted in a slender inline housing box could serve any number of 700V probes.
Those end window probes are sensitive and rugged, as are all the RADIAC series housings, to be sure.
Good project, thanks for posting it.
Geo
From: "STEPHEN CARLILE via groups.io" <smcarlile@...> To: "CDV700CLUB" < [email protected]> Sent: Wednesday, April 20, 2022 5:45:43 AM Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
------ Original Message ------
From: "STEPHEN CARLILE via groups.io" <smcarlile@...>
To: [email protected]
Sent: Wednesday, 20 Apr, 22 At 11:23
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
George, Thanks very much. I have looked everywhere for this manual.. The probe is the Low Range Unit, DT-507/PDR-63 as described on page 5-11 and shown in figure 5-5 page 5-19. It goes thru a box with resistors to calibrate the pulses / voltage...as shown on pages 5-11, 5-12, and 5-13. Thanks, Steve
------ Original Message ------
From: "Geo Dowell" <GEOelectronics@...>
To: "CDV700CLUB" <[email protected]>
Sent: Wednesday, 20 Apr, 22 At 10:59
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
Start with this manual Steve, and identify the model # of the probe. Geo From: "smcarlile via groups.io" <smcarlile@...> To: "CDV700CLUB" < [email protected]> Sent: Wednesday, April 20, 2022 3:26:57 AM Subject: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63 Hello, I have a probe from a non-working AN/PDR-63 and want to modify it to fit on a CDV-700. I do not have the book so I cannot share the schematics. I'd appreciate guidance from anyone who has done this modification. In addition, I am trying to track down a copy of the manual so I can post the schematics. Thanks Steve
|
Re: Need Help Modifying the Low Range Probe from AN/PDR-63
------ Original Message ------
From: "STEPHEN CARLILE via groups.io" <smcarlile@...>
To: [email protected]
Sent: Wednesday, 20 Apr, 22 At 11:23
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
George, Thanks very much. I have looked everywhere for this manual.. The probe is the Low Range Unit, DT-507/PDR-63 as described on page 5-11 and shown in figure 5-5 page 5-19. It goes thru a box with resistors to calibrate the pulses / voltage...as shown on pages 5-11, 5-12, and 5-13. Thanks, Steve
------ Original Message ------
From: "Geo Dowell" <GEOelectronics@...>
To: "CDV700CLUB" <[email protected]>
Sent: Wednesday, 20 Apr, 22 At 10:59
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
Start with this manual Steve, and identify the model # of the probe.
Geo
From: "smcarlile via groups.io" <smcarlile@...> To: "CDV700CLUB" < [email protected]> Sent: Wednesday, April 20, 2022 3:26:57 AM Subject: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
Hello, I have a probe from a non-working AN/PDR-63 and want to modify it to fit on a CDV-700. I do not have the book so I cannot share the schematics. I'd appreciate guidance from anyone who has done this modification. In addition, I am trying to track down a copy of the manual so I can post the schematics. Thanks Steve
|
Re: Need Help Modifying the Low Range Probe from AN/PDR-63
Steve is it possible to cut and paste the picture of the low-range probe?
Geo
From: "STEPHEN CARLILE via groups.io" <smcarlile@...> To: "CDV700CLUB" < [email protected]> Sent: Wednesday, April 20, 2022 5:23:57 AM Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
George, Thanks very much. I have looked everywhere for this manual.. The probe is the Low Range Unit, DT-507/PDR-63 as described on page 5-11 and shown in figure 5-5 page 5-19. It goes thru a box with resistors to calibrate the pulses / voltage...as shown on pages 5-11, 5-12, and 5-13. Thanks, Steve
------ Original Message ------
From: "Geo Dowell" <GEOelectronics@...>
To: "CDV700CLUB" <[email protected]>
Sent: Wednesday, 20 Apr, 22 At 10:59
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
Start with this manual Steve, and identify the model # of the probe. Geo From: "smcarlile via groups.io" <smcarlile@...> To: "CDV700CLUB" < [email protected]> Sent: Wednesday, April 20, 2022 3:26:57 AM Subject: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63 Hello, I have a probe from a non-working AN/PDR-63 and want to modify it to fit on a CDV-700. I do not have the book so I cannot share the schematics. I'd appreciate guidance from anyone who has done this modification. In addition, I am trying to track down a copy of the manual so I can post the schematics. Thanks Steve
|
Re: Need Help Modifying the Low Range Probe from AN/PDR-63
George, Thanks very much. I have looked everywhere for this manual.. The probe is the Low Range Unit, DT-507/PDR-63 as described on page 5-11 and shown in figure 5-5 page 5-19. It goes thru a box with resistors to calibrate the pulses / voltage...as shown on pages 5-11, 5-12, and 5-13. Thanks, Steve
toggle quoted message
Show quoted text
------ Original Message ------
From: "Geo Dowell" <GEOelectronics@...>
To: "CDV700CLUB" <[email protected]>
Sent: Wednesday, 20 Apr, 22 At 10:59
Subject: Re: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
Start with this manual Steve, and identify the model # of the probe.
Geo
From: "smcarlile via groups.io" <smcarlile@...> To: "CDV700CLUB" < [email protected]> Sent: Wednesday, April 20, 2022 3:26:57 AM Subject: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
Hello, I have a probe from a non-working AN/PDR-63 and want to modify it to fit on a CDV-700. I do not have the book so I cannot share the schematics. I'd appreciate guidance from anyone who has done this modification. In addition, I am trying to track down a copy of the manual so I can post the schematics. Thanks Steve
|
Re: Need Help Modifying the Low Range Probe from AN/PDR-63
Start with this manual Steve, and identify the model # of the probe.
Geo
From: "smcarlile via groups.io" <smcarlile@...> To: "CDV700CLUB" < [email protected]> Sent: Wednesday, April 20, 2022 3:26:57 AM Subject: [CDV700CLUB] Need Help Modifying the Low Range Probe from AN/PDR-63
Hello, I have a probe from a non-working?AN/PDR-63 and want to modify it to fit on a CDV-700. I do not have the book so I cannot share the schematics. I'd appreciate guidance from anyone who has done this modification. In addition, I am trying to track down a copy of the manual so I can post the schematics. Thanks Steve
|
Need Help Modifying the Low Range Probe from AN/PDR-63
Hello, I have a probe from a non-working?AN/PDR-63 and want to modify it to fit on a CDV-700. I do not have the book so I cannot share the schematics. I'd appreciate guidance from anyone who has done this modification. In addition, I am trying to track down a copy of the manual so I can post the schematics. Thanks Steve
|
Re: Question and an interesting site for those that modify CDV700s and more.
Is there a negative Voltage version? Geo
From: "peter via groups.io" <epkoncept@...> To: "CDV700CLUB" < [email protected]> Sent: Tuesday, April 19, 2022 6:22:29 PM Subject: Re: [CDV700CLUB] Question and an interesting site for those that modify CDV700s and more.
Digression:
?Microchip LR8?
? ?~$1
3 pin regulator, good up to 450 V input, max 438V output?
( only if it could be easily stacked!)
P
|
Re: Question and an interesting site for those that modify CDV700s and more.
toggle quoted message
Show quoted text
From: "peter via groups.io" <epkoncept@...> To: "CDV700CLUB" < [email protected]> Sent: Tuesday, April 19, 2022 6:22:29 PM Subject: Re: [CDV700CLUB] Question and an interesting site for those that modify CDV700s and more.
Digression:
?Microchip LR8?
? ?~$1
3 pin regulator, good up to 450 V input, max 438V output?
( only if it could be easily stacked!)
P
|
Re: Question and an interesting site for those that modify CDV700s and more.
Digression:
?Microchip LR8?
? ?~$1
3 pin regulator, good up to 450 V input, max 438V output?
( only if it could be easily stacked!)
P
|
CDV-700 "OPERATIONAL CHECK SOURCE" gamma ray analysis to ID contents
About 16 hours into a 24 hour Gamma Spectrometry test on an unkown CDV-700 Check Spot.
Looking like Uranium based, not radium based, and the lack of U-235 markers suggests a oretty good grade of DEPLETED Uranium
Just a picture for now, the chek spot is in red, the blue outline above it is the scan we dis yesterday of a known?1938 pre WW2?chemically separated natural uranium oxides, only U in its natural abundance, no radium, or other lower daughters.
In this sort of sample there are atoms of the U-238 decay chain down to Thorium-230, and U-235 decay chain: U-235/ Th-231/ Pa-231
Uranium ore as we know it on earth could theoretically?be chemically separated from ore all the way back to the primordial?U-238/U-235/U-234, these would take millennia?to significantly replace natural?radium again.
Geo
|
From: "peter via groups.io" <epkoncept@...> To: "CDV700CLUB" < [email protected]> Sent: Wednesday, April 13, 2022 11:36:47 PM Subject: [CDV700CLUB] test for 220413
test if I can post today?
P
|
Re: Question and an interesting site for those that modify CDV700s and more.
Good evening.
Well I added a npn pass transistor to the shunt regulator. It works like a dream.
Didn't have a hv transistor so I used 60V rated tr 2SD1406.? It has a HFE~ 300
I think I have the circuit I want. I guess the next thing is to see if I can add some filter caps into the circuit to see if it can also work as a
capacitance multiplier for some heavy duty ripple filtering!
Not too familiar with my circuit simulator so I have to figure out how to add ripple to the voltage source in the simulation.
|
Re: Question and an interesting site for those that modify CDV700s and more.
Thanks, Clay.
rogerw
On 4/7/2022 6:42 PM, freshndaire wrote:
Roger (and all),
? Here is the link to the Victoreen tube catalog from the
logwell.com site that has Corotron info:?
Clay
--
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 (and all),
? Here is the link to the Victoreen tube catalog from the logwell.com site that has Corotron info:?
Clay
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Re: Question and an interesting site for those that modify CDV700s and more.
Hi Geo,? I hadn’t run across that Victoreen unit, pretty fancy.? Does a lot more logging, etc. Off-topic X-ray ramblings alert. ? The dosimeter at work was a RaySafe the size of an Ipod mini or a really small candy bar phone but really thin.? It wasn’t fancy, was always on and ran for well over a year, maybe over 2 years on the internal battery.? It captured any pulse it saw above its threshold.? Pretty much useless for anything but what it was intended for.? It had no buttons and only “listened” for X-ray pulses.? Similar to this newer model: ? but it was black and it didn’t have an easily removable back.? We sent it in for calibration and they replaced the battery.? It only spoke X-ray, to change the units you had to use an X-ray generator!? I can’t find my old notes on how to change ranges but it was easy if you remembered the procedure.? To use it you just opened the collimator, set the correct distance from the tube in the generator, made sure the laser pointers were on the center of the target and fired the “shot”.? We also had a Fluke TNT12000D IIRC that I sometimes used when the RaySafe was out at a trade show or whatever.? Compared to the RaySafe it was massive. ? The vet systems used mainly MinXray ?or Poskom ?portable Generators.? The all-in-one systems we sold contained everything except the wireless receptor in a package the size of a typical small portable generator.? ?The viewing system was removable from the generator section so you didn’t have to lug the generator along to show the customer an image.? It was basically a tablet in a housing with the receptor comms and wireless hub. I have one, I don’t know if it still works or has a receptor licensed to it.? They are pretty cool but the portable generators were a bit wimpy for horse “stifles” and spine shots.? Lots of animal to go through.? If you turn the receptor around backward you get a nice image of the boards and batteries inside.? The Ultra Caps in the portable generators fail slowly over time and affect the output, so we always ran a series of test shots to confirm the dose. ?I have some scrap X-ray “tanks”.? They have oil, a multiplier, a couple of transformers and the tube in them.? I have more pictures and should still have that tank out in the shop.? I wish I had full documentation on them. ?Pic 100-1237 shows an opened tank, if you look closely at the cover lower edge you can see the failure mechanism- cracks in the housing.? As the oil leaks out it makes a huge mess inside the generator and a bubble in the tank that causes arcing which generates a fault reported by the generator.? It is a crap case design, but they extended the warranty so we changed many of them.? I was able to refill one that had a bubble but no leaks, it may still be good.? You have to pull a slight vacuum on the bellows inside that allows for oil volume changes with temperature.? Not an easy process.? I have a few of the bad tanks.? I also have a big rotating anode X-ray head from a large wheeled portable system like you would see in a hospital.? It has an issue with the tube that made it “not of clinical quality”.? It has a lot of oil in it and the tube is a work of art if you are into that sort of thing (I am!).? I took one apart at work but someone else wound up with it.? This one is waiting for me to decide if it is “tube art” or will I try to power it.? That would be a huge and risky project so I am just planning to pull it apart.? It would be cool to be able to run the anode motor.? Kind of a cool magnetic coupling with the motor’s rotor operating in a vacuum. ? For a really big GM tube with a side window see Ebay 283349395433 Clay ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Geo Dowell
Sent: Thursday, April 07, 2022 1:01 PM
To: CDV700CLUB
Subject: Re: [CDV700CLUB] Question and an interesting site for those that modify CDV700s and more.? " ??I worked as an X-ray repair tech at my last job.? Medical and Veterinary X-ray at first, then the Medical side split off.? Mostly field portable stuff.? We had a really cool X-ray dosimeter tool that could be configured for different measurement units.? I may have some info on it still in my archives.? It would record the kVp, mAs, and dose from an exposure. " Clay does "Victoreen NERO" ring any bells?
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Re: Question and an interesting site for those that modify CDV700s and more.
oops, just realized a brain-fart below. The
ENi secondary peak must be about 900+V..... 930+/-20V in the
manual.
And it is Zener regulated to 15.5V in the
primary.
930/15.5 = 60
Hmmmm.... I don't understand everything I
know...
rogerw
On 4/7/2022 4:24 PM, Roger Whatley via
groups.io wrote:
1) So, in a Lionel the primary "flyback"
voltage should be about 15.5V peak. Then after a diode drop
and limited by the loading of the one-shot pulse detector on
the -15V line. This -15V is regulated in the primary when the
900+ shunt regulator pulls energy in the secondary (and which
energy is sucked from the primary....), ergo regulation on
both ends of the transformer.
And in the similar ENi it is Zener regulated
in the primary to 15.5V, ergo regulated in the secondary too,
without a secondary shunt regulator.
2) I think I asked the earlier question
without much clarity in my own mind..... Let me re-phrase:
In a Lionel with the secondary shunt
regulation in place, what is the secondary winding peak
voltage? 1350V?
In an ENi with the primary shunt regulation
in place, what is the (unloaded, as is) secondary winding peak
voltage? also 1350V, perhaps?
If 1350V is the right number, that suggests
to me a windings ratio of 1350/15.5 = 87.? Off the top of my
head, I think I was using ratio=77 2+ years ago..... which
would be 1200V peak secondary.
I might go do some sims later with that.
rogerw
On 4/7/2022 3:44 PM, Geo Dowell
wrote:
Yes I have measured totally unregulated rectified ,
and no that's not it. 1350 is where I pre regulate the
made-from-CDV-700-transformer bias supplies for use in
and with shop made testing equipment. Without that, it
is much higher, too much in fact, probably the main
cause of internal arcing/failure of them in the
CDV-700's. Nothing on that PCB can withstand 2kV+
This is why when doing a HV rectifier upgrade,
replace Corotron (if present, ENi has none) or add the
Zener stack FIRST, check it for working, THEN replace
the diode.
Geo
From: "Roger Whatley" <rogwhat53@...>
To: "CDV700CLUB" <[email protected]>
Sent: Thursday, April 7, 2022 3:12:31 PM
Subject: Re: [CDV700CLUB] Question and an
interesting site for those that modify CDV700s and more.
Geo,
1) have you ever measured an
unregulated HV output , after rectification but
without Shunt Regulator loading, of a
Vic/Lionel/ENi with a 1G meter?
?Is that the 1300V figure you
used earlier?
2) The Vic 6/6A manual on page 4
says this will be about 1100V, but that is likely
not open-circuit but rather loaded in-circuit.
rogerw
On 4/7/2022 2:55 PM, Geo
Dowell wrote:
That tracks with bench measurements
gentlemen, I'm seeing full rated V at 1000 M
Ohms load and 1 kV DC, but not at 10,000 M Ohms.
Now on to the next measurement which requires
an electrostatic Voltmeter.
Geo
From: "Roger Whatley" <rogwhat53@...>
To: "CDV700CLUB" <[email protected]>
Sent: Thursday, April 7, 2022 2:33:36 PM
Subject: Re: [CDV700CLUB] Question and
an interesting site for those that modify
CDV700s and more.
Ah! Excellent! Down to
1uA with 10uA being comfortably on the
curve, and that is a 1/2Watt Zener which
is the most common kind I see.
I notice the Zener (or
Avalanche) voltage increases linearly up
to about 1mA, then increases at a higher
rate, no doubt due to extrinsic series
resistance in the bulk material of the
chip. I wonder why they spec operation in
the tables at 5mA?
rogerw
On 4/7/2022 2:25
PM, peter via groups.io wrote:
Roger et al:
?figure 1 in the attached Rohm spec sheet
show? current vs voltage for their various
zeners.
--
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.
--
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.
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Michael C
