The jumping needle in the dosimeter pen could very well be caused by dirt in the zero control. A little QD or DeOxit would likely solve that issue. The same problem happens very regularly to volume control pots.
Thanks for the informative video. I think we trained with that same Docimeter and charger when I was in the US Army in late 70s and 80s. Ours were OD green of course. I have considered getting one of the 715 survey meters untested for $19.99 just for fun. I realize it is only for use after we have been nuked.
This is great info, thank you for sharing your knowledge! I have a Victoreen Instrument Co. Model 1A CDV-715. The dial is stuck just past the "2" either with or without a fresh battery in place (I checked the battery to make sur eit was fully-charged). Any suggestions on how I can get it to work? Thank you in advance.
If using the zero knob back and forth a few times and physically jarring the unit to see if the needle frees up, you probably need a new dial indicator (gauge).
At the time this equipment was designed it was adequate for what it was intended for. The high level survey meter or ion chamber meter, he is correct you will probably not even get that needle to Flinch on anything that you could legally own. Possibly if you were nice and asked when you went to the dentist office you could put it on the opposite side of your face from where they do the X-ray and for a very brief second see the needle Flinch on the lowest setting. On the dosimeters, regardless of how smooth the charger is that's usually due to the rheostat inside being dirty, other than that the circuit is extremely simple and it's the same across all the different models. The high voltage is used to charge the dosimeter which send it back down the scale, as radiation enters the open end of the decimeter or through the case, it loses the ionic charge. Thereby causing the needle to rise up the scale the problem is all of these decimeters regardless of which model you have except for maybe the v-138. We're designed to be used above 10r, that you would encounter this. Should there be an actual emergency with nuclear material. If it is localized to say a construction site or a manufacturing facility, or a laboratory the average civilian population will not have to worry despite what they believe on government conspiracies and government cover up. There is a safe boundary Zone built around these places is designed to protect the public from radiation leaks and accidents. By the time you would need any of these meters other than the basic Geiger counter. The situation would be far dire than anyone can seriously imagine and anything you've learned on basic shelter and place techniques, or ways of protecting yourself from radiation, are going to be a very little use due to the fact that we don't practice them every minute of every day. Slight little things that you will do in your average hours of just walking around your house or touching and moving things. You will cause contamination. The procedures we use in Laboratories to prevent this are very thorough and are practiced, and usually there are people watching every move so that if somebody misses a step we stop decontaminate or stop and go back. Again these devices were designed to withstand the initial Fallout of a atomic attack. They are not Precision lab instruments. Although some of them are quite good and were based on very good equipment at the time you have to look at it as what it is 70-year-old technology. Although the fundamentals don't change, they're accuracy does and there's only one company in the United States that will still calibrate these old meters. And even they tell you if there is a certain tolerance, plus or minus a certain amount. The basic geiger counter is fun to play with check smoke detectors and other random things for low-level radiation looking for radioactive glass radium sources. Coleman lantern mantles things of that nature. That's why many of them were given to schools by the state when the Civil Defense programs were shut down. Most of the high level leaders were sold off at auction for their electronics parts value. As even the government knew that people did not have a need for meter that would read these levels to give you an idea if you're in an environment that is exposing you to 10 rentons per hour. Radiation you would be able to stay in that environment for roughly 10 hours. Before you exceeded a total body dose. The problem is you would have to be able to escape to an area that is almost zero to continue not receiving a calculated dose and at 100 rent-kin for 10 hours. You would be quite sick. I would serious medical attention something that your basic iodine tablets are not going to protect you from also most likely whatever is creating this high level is either going to be a source that was incorrectly shielded, or has broken open and the contents that Spilled Out or God forbid an actual atomic detonation. You're going massive amounts of contamination most people do not have a multi-chamber decontamination system setup to be ran through containing multiple showers and clothing changes. To wash the radiation off where most people think that I I can wash it off outside with buckets of water or a couple pump up sprayers full of water. Yes that would work for maybe one person the problem is if it's still floating in the air, you're going to immediately contaminate the inside of your shelter. Also should your meters become contaminated which is quite easy to do. They're going to give you false readings. So the information he's giving you will only the most very basic, understand that the average person regardless of how many conspiracy theories they believe in. Will never face radiation levels is high in the environment even in the event of an accident even if your next door neighbor is one of the few operating Atomic plants in this world. You're not going to receive any kind of dose of radiation due to the hundreds and hundreds of safeguards that exist around this stuff as much as movies want you to believe that it's fairly handled casually and no one those were old documentaries based on how things were handled in the 1940s and '50s before we understood the dangers of these items by the 1980s we realized how dangerous they were and we improved our designs and our containment systems. So yes you might think you got something that will protect you or at least tell you that there is higher levels of radiation but worrying about the microscopic amounts of background radiation you find in food and water on average daily basis or in that old glass jar that left by your grandmother. Are no higher than what you'd receive in a commercial airline flying from Los Angeles to New York. The reason that do senators low level ones will read upscale after a few hours of being charged, is from ionic radiation coming from the sky and the natural background radiation around us. There's nothing you can do about it. For those that are going to take these items and go explore old uranium mines in the southwest I highly suggest you do not enter them not because of the radiation but due to the unstable nature of the mining operations these mines were sealed off and barricaded for a reason. The tunnels have not been inspected the curing and supports have also not been inspected. Just the fact that you touched a wall could cause it to crumble. Or cause a crack to migrate it would cause a fatal collapse. Never go into an underground mind. It has been abandoned well it may seem like a cool thing to post your TH-cam video about understand just how and the least of your worries are going to be the radiation levels. Just two cents of advice from a former Lawrence Livermore Laboratories engineer. Radiation is nothing to mess with it's an interesting field of science to experiment, but realized that there's a reason that the government restricts the power level of sources available to the general public. As they're easily mishandles and can be deadly.
Radiological survey meters are meant for nuclear war, deadly levels of radiation. If one had a means of protecting from gamma radiation, in a nuclear war event these are useful for determining when it is safe enough to leave the shelter.
The needle on my CDV 715 is stuck in the center of the gauge at all times - with or without a battery in place. Any suggestions as to how to get it to respond to the battery would be very much appreciated. Thanks in advance.
I have a Victoreen CDV 700 6A. It seems to work right at first glance, but it is not. Even when not near a source, if the unit is turned on at any setting, the needle begins to slowly climb. In about 15 minutes it is maxed out to the right hand side. I am not sure what part to replace in it.
I have a cdv 720, but need help figuring out what’s wrong with it. Circuit check and zero work fine, but the 100-1 maxes out the gauge and it makes a humming noise.
The CD-V720's were problematic/unreliable and they were discontinued because of that. I don't know the answer to your question, but if you thought it was worth saving you could ask if KI4U would look at it: www.radmeters4u.com/calibrate.htm An electronics technician would probably be able to diagnose it with the schematic diagram inside the bottom case.
I just acquired a Victoreen cdv-700 6b and it seems to work good other than the just reading a random number when off with no clicks until I tap on it a lot, and when I turn it on to test it will do the proper clicks and read 0 until I tap on it a bit. I suspect something being sticky in the meter but I have no clue what. Any ideas?
The number one thing I have bad on that model is bad dial indicators (gauge). Replacing the gauge is probably all you could do if you could find one. I need dozens of them myself.
I have one of the Jordan Electronics dosimeter chargers but found mines doesn't seem to charge the dosimeter. The light works fine but when adjusting the knob of the charger, it doesn't seem to do anything to the scale of dosimeter. I tested it with 3 dosimeters I have so I would think its highly unlikely it's the dosimeters themselves. Not sure if you know how to fix it but any advice would be appreciated.
Find an owners manual online for that model orau.org/health-physics-museum/library/civil-defense/manuals.html In there they describe how to adjust the transformer with a screwdriver on R2 pot on the back. This often does the trick.
Hi there, I recently purchased a Victoreen CDV 715 1A that has a slight crack in the meter bezel/dial indicator. Will this cause problems with its ability to function? The ionization chamber still looks sealed and seems to work fine except for the fact that it reads about .3 r/hr when I switch it to the two lowest settings. It was last calibrated in 2016 so I wouldn’t think it would be too off, but was wondering with your experience with these what you had to say- thanks!
All of them will do what you are saying. When the government owned them they would calibrate them every 4 years. The crack shouldn't present a problem.
They are both built to the same government specs, but they are different inside. In general here's a listing in order of which I think are the best brands of the model CD-V700 model 6 (or 6A, 6B): 1. Victoereen 2. Lionel 3. Electro Neutronics Inc. (ENI) 4. Anton Hope this helps.
So I got a Cdv-715 just for something cool to have and for some reason when I do the circuit check it goes all the way up like past the 5 even and when I put it on zero same thing and the knob to adjust it isn’t changing it and when I put it on the X100 X10 X1 and X0.1 it goes past the five which I know it shouldn’t be doing so is it something I can fix?
Hi, I just got the CD-V 700 model 6b yesterday. It was working fine until this morning. I put in the batteries and I was getting nothing. I checked with a multimeter and it was a connectivity issue so I cleaned off some corrosion and it worked fine. When I checked the source the dial worker but it just stopped at .3 mr/hr. Will I have to replace the dial or is it a fixable problem? It is the flat dial , by the way
It's been so long since I did this video, I'm not sure if I mentioned it. The model 700 has meter failure as the #1 breakdown. The dial indicator is sealed and would need to be replaced, although I have seen people cut them open and repair them. You will have a hard time finding a replacement dial indicator, I need about 50 of them myself.
@@ForbiddTV nevermind, all is good, for now.. just turned it on, the dial is working now. Thanks for all the help, usually people don’t reply to comments from a 5 year old video. I like all your CD stuff and I hope to see more of it one day
I am finding it hard to find the V-715 1B version with the "R" stamp; since this is a later model, was the retrofit improvements already built in unlike the 1A and 1 models, or do I need to keep looking to make sure I get the R version?
I have seen many 1B stamped with the R, but I think this was only done to avoid confusion from those who didn't understand the 1964 model 1B already had the changes necessary built in. Usually it was an ink stamp on top near the nameplate or on the circuit board. Sometimes it is a round white sticker near the nameplate.
For some reason whenever I put mine on the zero setting it started bouncing you’re not staying still do you have any idea what could be causing this it’s been doing this for a while now ?
No talk about the corotron tube failures in the CDV700s? This is important to know, they all fail after 22years and over volt the Geiger Muler tube and either damage it or destroy the unobtainable high voltage transformer
The 720's were a curious one, but unfortunately not many exist anymore. There were reliability problems which caused most of them to be removed from service.
I just got one of your dosimeter calibrators that seems to have worked very intermittently then failed. At first the bulb would occasionally turn on long enough for a flicker, now it wont work at all. Contacts are engaging fully. Switching bulbs and batteries doesnt help. Any advice?
SixR I certainly have seen some bad ones, but I don't really know at what rate they go bad. I don't have very many of them as most were removed from service back in the 60's because of reliability issues.
ForbiddTV I was just wondering because I recently bought one from Coleman's Military Supply which states that they came from a surplus warehouse or something like that. The one I received actually looks like it's not that bad of a shape it seems to have a couple of scratches but they seem to be near the beta radiation shield. It says it's been tested but I have not been able to find out if it zeros or circuit checks it's also still has the original CD logo on it it also has the shoulder strap that came with it as well. Update I have been able to get batteries to test it , it zeros in just fine and it circuit checks just fine as well.
ForbiddTV The main reason why I bought it was because Wikipedia made it seem to me that this model was the only one that detected both Beta and Gamma and I was also told they are hard to come by as well, but of course Wikiapedia being Wikiapedia they seem to think you need a Geiger counter with a Radiation Survey Meter even though it wouldn't really work with a Radiation Survey Meter because if you're detecting anything on the Radaiation Survey Meter the counter wouldn't even work anyways. But seeing from your other videos I can tell this model is not the only one that tests for both. I don't want to seem that im that kind of person that just buys Geiger Counters or Radiation Survey Meters because of Fukashima or something I've always been interested in radiation detection devices because I find them very interesting and also to count for the fact that I like old technology.
SixR That's partly true. Of all the Civil Defense era survey meters, that is the only model that will detect both beta and gamma radiation. However, virtually any geiger counter will detect both beta and gamma at low (not dangerous) levels.
I was having an issue with a 700.. I was metering some rocks and it started jumping off the scales.. I had the headphones in and it made a funny sound acting like i was standing in Chernobyl or something.. Well I took the batteries out and put em back in and it worked fine.. Any ideas what caused it? Also LOVE the videos keep up the good work
I have a Radiological survey meter CD V-700 Model 5, and just yesterday it was working fine. but today when i turned it on i didn't hear any clicks and i didn't see the Needle on the dial move. What is your diagnosis? ( Note, the batteries are brand new )
Lord Dubious 22 It could be a number of things but the number one problem I have with these units is a non-working dial indicator. In your case since you can still hear clicks that's not the problem. It could be the geiger Muller tube or any of the electronics inside the unit itself hard to tell with only the information I have.
ForbiddTV I don't hear any clicks and the dial isn't moving. When I turn it on I hear a small buzzing sound in the headphones. Just like I did when it worked.
Lord Dubious 22 I'm sorry, I misread your symptoms earlier. In your case I would try to swap out another geiger Muller tube from a working unit (needs no tools) to test that theory if you can find one without having to buy it. They got a lot more expensive since the 2011 Japan accident. If that doesn't work then you got a problem in the electronics somewhere.
My limited experience indicates something bad in the high voltage side, the probe wiring, or the tube itself. I have one that still clicks,but no meter movement. After removing the meter out of the circuit, I discovered the meter was open, or burned out. Incidentally, do not use a standard old style volt ohm meter, as it has enough voltage to burn out the meter. It's only a 50 ua movement and the measurement voltage can fry it almost instantly. The circuit caries 1V or so fed to the meter thru a 2300 ohm. resistor, so use one of this value or higher to check the meter continuality. But it appears you have a HV problem. Could be the voltage regulator has failed, which will drop Geiger tube voltage dramatically. If you are not electronically inclined, repair services are available on the internet.
loved your vid. I worked at Victoreen for 18 years. I started in 1980. it sure was nice to see those yellow boxes.
I understand it's a Superfund site south of Cleveland now.
The jumping needle in the dosimeter pen could very well be caused by dirt in the zero control. A little QD or DeOxit would likely solve that issue. The same problem happens very regularly to volume control pots.
Thank you had the pleasure of meeting you in Wisconsin at your seminar.
Thanks for the informative video. I think we trained with that same Docimeter and charger when I was in the US Army in
late 70s and 80s. Ours were OD green of course. I have considered getting one of the 715 survey meters untested for $19.99 just for fun. I realize it is only for use after we have been nuked.
This is great info, thank you for sharing your knowledge! I have a Victoreen Instrument Co. Model 1A CDV-715. The dial is stuck just past the "2" either with or without a fresh battery in place (I checked the battery to make sur eit was fully-charged). Any suggestions on how I can get it to work? Thank you in advance.
If using the zero knob back and forth a few times and physically jarring the unit to see if the needle frees up, you probably need a new dial indicator (gauge).
Lovely video, lovely detectors.
At the time this equipment was designed it was adequate for what it was intended for. The high level survey meter or ion chamber meter, he is correct you will probably not even get that needle to Flinch on anything that you could legally own. Possibly if you were nice and asked when you went to the dentist office you could put it on the opposite side of your face from where they do the X-ray and for a very brief second see the needle Flinch on the lowest setting. On the dosimeters, regardless of how smooth the charger is that's usually due to the rheostat inside being dirty, other than that the circuit is extremely simple and it's the same across all the different models. The high voltage is used to charge the dosimeter which send it back down the scale, as radiation enters the open end of the decimeter or through the case, it loses the ionic charge. Thereby causing the needle to rise up the scale the problem is all of these decimeters regardless of which model you have except for maybe the v-138. We're designed to be used above 10r, that you would encounter this. Should there be an actual emergency with nuclear material. If it is localized to say a construction site or a manufacturing facility, or a laboratory the average civilian population will not have to worry despite what they believe on government conspiracies and government cover up. There is a safe boundary Zone built around these places is designed to protect the public from radiation leaks and accidents. By the time you would need any of these meters other than the basic Geiger counter. The situation would be far dire than anyone can seriously imagine and anything you've learned on basic shelter and place techniques, or ways of protecting yourself from radiation, are going to be a very little use due to the fact that we don't practice them every minute of every day. Slight little things that you will do in your average hours of just walking around your house or touching and moving things. You will cause contamination. The procedures we use in Laboratories to prevent this are very thorough and are practiced, and usually there are people watching every move so that if somebody misses a step we stop decontaminate or stop and go back. Again these devices were designed to withstand the initial Fallout of a atomic attack. They are not Precision lab instruments. Although some of them are quite good and were based on very good equipment at the time you have to look at it as what it is 70-year-old technology. Although the fundamentals don't change, they're accuracy does and there's only one company in the United States that will still calibrate these old meters. And even they tell you if there is a certain tolerance, plus or minus a certain amount. The basic geiger counter is fun to play with check smoke detectors and other random things for low-level radiation looking for radioactive glass radium sources. Coleman lantern mantles things of that nature. That's why many of them were given to schools by the state when the Civil Defense programs were shut down. Most of the high level leaders were sold off at auction for their electronics parts value. As even the government knew that people did not have a need for meter that would read these levels to give you an idea if you're in an environment that is exposing you to 10 rentons per hour. Radiation you would be able to stay in that environment for roughly 10 hours. Before you exceeded a total body dose. The problem is you would have to be able to escape to an area that is almost zero to continue not receiving a calculated dose and at 100 rent-kin for 10 hours. You would be quite sick. I would serious medical attention something that your basic iodine tablets are not going to protect you from also most likely whatever is creating this high level is either going to be a source that was incorrectly shielded, or has broken open and the contents that Spilled Out or God forbid an actual atomic detonation. You're going massive amounts of contamination most people do not have a multi-chamber decontamination system setup to be ran through containing multiple showers and clothing changes. To wash the radiation off where most people think that I I can wash it off outside with buckets of water or a couple pump up sprayers full of water. Yes that would work for maybe one person the problem is if it's still floating in the air, you're going to immediately contaminate the inside of your shelter. Also should your meters become contaminated which is quite easy to do. They're going to give you false readings. So the information he's giving you will only the most very basic, understand that the average person regardless of how many conspiracy theories they believe in. Will never face radiation levels is high in the environment even in the event of an accident even if your next door neighbor is one of the few operating Atomic plants in this world. You're not going to receive any kind of dose of radiation due to the hundreds and hundreds of safeguards that exist around this stuff as much as movies want you to believe that it's fairly handled casually and no one those were old documentaries based on how things were handled in the 1940s and '50s before we understood the dangers of these items by the 1980s we realized how dangerous they were and we improved our designs and our containment systems. So yes you might think you got something that will protect you or at least tell you that there is higher levels of radiation but worrying about the microscopic amounts of background radiation you find in food and water on average daily basis or in that old glass jar that left by your grandmother. Are no higher than what you'd receive in a commercial airline flying from Los Angeles to New York. The reason that do senators low level ones will read upscale after a few hours of being charged, is from ionic radiation coming from the sky and the natural background radiation around us. There's nothing you can do about it. For those that are going to take these items and go explore old uranium mines in the southwest I highly suggest you do not enter them not because of the radiation but due to the unstable nature of the mining operations these mines were sealed off and barricaded for a reason. The tunnels have not been inspected the curing and supports have also not been inspected. Just the fact that you touched a wall could cause it to crumble. Or cause a crack to migrate it would cause a fatal collapse. Never go into an underground mind. It has been abandoned well it may seem like a cool thing to post your TH-cam video about understand just how and the least of your worries are going to be the radiation levels. Just two cents of advice from a former Lawrence Livermore Laboratories engineer. Radiation is nothing to mess with it's an interesting field of science to experiment, but realized that there's a reason that the government restricts the power level of sources available to the general public. As they're easily mishandles and can be deadly.
Radiological survey meters are meant for nuclear war, deadly levels of radiation. If one had a means of protecting from gamma radiation, in a nuclear war event these are useful for determining when it is safe enough to leave the shelter.
True!
The needle on my CDV 715 is stuck in the center of the gauge at all times - with or without a battery in place. Any suggestions as to how to get it to respond to the battery would be very much appreciated. Thanks in advance.
Good info
It is a shame these are non-obtainium in the UK. When they do pop up they are expensive.
The same can be said about British equipment here in the US.
I have a Victoreen CDV 700 6A. It seems to work right at first glance, but it is not. Even when not near a source, if the unit is turned on at any setting, the needle begins to slowly climb. In about 15 minutes it is maxed out to the right hand side. I am not sure what part to replace in it.
Yeah, this is not normal and I don't know what to tell you how to fix it,
@@ForbiddTV I was thinking a leaky capacitor maybe.
I have a cdv 720, but need help figuring out what’s wrong with it.
Circuit check and zero work fine, but the 100-1 maxes out the gauge and it makes a humming noise.
The CD-V720's were problematic/unreliable and they were discontinued because of that. I don't know the answer to your question, but if you thought it was worth saving you could ask if KI4U would look at it: www.radmeters4u.com/calibrate.htm
An electronics technician would probably be able to diagnose it with the schematic diagram inside the bottom case.
I love cold war stuff
I just acquired a Victoreen cdv-700 6b and it seems to work good other than the just reading a random number when off with no clicks until I tap on it a lot, and when I turn it on to test it will do the proper clicks and read 0 until I tap on it a bit. I suspect something being sticky in the meter but I have no clue what. Any ideas?
The number one thing I have bad on that model is bad dial indicators (gauge). Replacing the gauge is probably all you could do if you could find one. I need dozens of them myself.
I have one of the Jordan Electronics dosimeter chargers but found mines doesn't seem to charge the dosimeter. The light works fine but when adjusting the knob of the charger, it doesn't seem to do anything to the scale of dosimeter. I tested it with 3 dosimeters I have so I would think its highly unlikely it's the dosimeters themselves. Not sure if you know how to fix it but any advice would be appreciated.
Find an owners manual online for that model orau.org/health-physics-museum/library/civil-defense/manuals.html In there they describe how to adjust the transformer with a screwdriver on R2 pot on the back. This often does the trick.
Hi there, I recently purchased a Victoreen CDV 715 1A that has a slight crack in the meter bezel/dial indicator. Will this cause problems with its ability to function? The ionization chamber still looks sealed and seems to work fine except for the fact that it reads about .3 r/hr when I switch it to the two lowest settings. It was last calibrated in 2016 so I wouldn’t think it would be too off, but was wondering with your experience with these what you had to say- thanks!
All of them will do what you are saying. When the government owned them they would calibrate them every 4 years. The crack shouldn't present a problem.
Good to hear! Thank you for the help, I really appreciate it :)
Do the CDV-700 Geiger Counters detect X-ray radiation?
Yes, but you won't be able to separate readings of gamma and X-ray.
Do you more info on the differencies betwen lionel and victoreen ?
They are both built to the same government specs, but they are different inside. In general here's a listing in order of which I think are the best brands of the model CD-V700 model 6 (or 6A, 6B):
1. Victoereen
2. Lionel
3. Electro Neutronics Inc. (ENI)
4. Anton
Hope this helps.
@@ForbiddTV ty
So I got a Cdv-715 just for something cool to have and for some reason when I do the circuit check it goes all the way up like past the 5 even and when I put it on zero same thing and the knob to adjust it isn’t changing it and when I put it on the X100 X10 X1 and X0.1 it goes past the five which I know it shouldn’t be doing so is it something I can fix?
Sorry, I do not know of the fix but am working with KI4U on a video addressing these more detailed problems.
I have a CDV-715 that will not move to zero. Any tips on how to make this work?
Try different batteries. If it's pegging to the right or left, no.
Hi, I just got the CD-V 700 model 6b yesterday. It was working fine until this morning. I put in the batteries and I was getting nothing. I checked with a multimeter and it was a connectivity issue so I cleaned off some corrosion and it worked fine. When I checked the source the dial worker but it just stopped at .3 mr/hr. Will I have to replace the dial or is it a fixable problem? It is the flat dial , by the way
It's been so long since I did this video, I'm not sure if I mentioned it. The model 700 has meter failure as the #1 breakdown. The dial indicator is sealed and would need to be replaced, although I have seen people cut them open and repair them. You will have a hard time finding a replacement dial indicator, I need about 50 of them myself.
@@ForbiddTV thank you for the information. I am hoping I just need to replace the batteries, since they are low.
@@ForbiddTV nevermind, all is good, for now.. just turned it on, the dial is working now. Thanks for all the help, usually people don’t reply to comments from a 5 year old video. I like all your CD stuff and I hope to see more of it one day
I am finding it hard to find the V-715 1B version with the "R" stamp; since this is a later model, was the retrofit improvements already built in unlike the 1A and 1 models, or do I need to keep looking to make sure I get the R version?
I have seen many 1B stamped with the R, but I think this was only done to avoid confusion from those who didn't understand the 1964 model 1B already had the changes necessary built in. Usually it was an ink stamp on top near the nameplate or on the circuit board. Sometimes it is a round white sticker near the nameplate.
@@ForbiddTV Thank you!
For some reason whenever I put mine on the zero setting it started bouncing you’re not staying still do you have any idea what could be causing this it’s been doing this for a while now ?
Not a real reading, you have a model that needs repair.
No talk about the corotron tube failures in the CDV700s? This is important to know, they all fail after 22years and over volt the Geiger Muler tube and either damage it or destroy the unobtainable high voltage transformer
I want to do a more detailed video on problems with these units, but it's a big topic and I'm not as up on the electronics as you seem you might be.
What about the functionality of the CDV 720's? I'd really appreciate some more information about that particular model. Thanks.
The 720's were a curious one, but unfortunately not many exist anymore. There were reliability problems which caused most of them to be removed from service.
I just got one of your dosimeter calibrators that seems to have worked very intermittently then failed. At first the bulb would occasionally turn on long enough for a flicker, now it wont work at all. Contacts are engaging fully. Switching bulbs and batteries doesnt help. Any advice?
If you bought it from me, write to me and we will get you another one.
Where do I order a t shirt at? Super kool
I made it, sorry. I even had the patches made as well.
ForbiddTV super cool.
Can I buy one of these from you?
The information is in the "about" section.
Is that dial indicator problem known to happen with the CDV-720's?
SixR I certainly have seen some bad ones, but I don't really know at what rate they go bad. I don't have very many of them as most were removed from service back in the 60's because of reliability issues.
ForbiddTV I was just wondering because I recently bought one from Coleman's Military Supply which states that they came from a surplus warehouse or something like that. The one I received actually looks like it's not that bad of a shape it seems to have a couple of scratches but they seem to be near the beta radiation shield. It says it's been tested but I have not been able to find out if it zeros or circuit checks it's also still has the original CD logo on it it also has the shoulder strap that came with it as well. Update I have been able to get batteries to test it , it zeros in just fine and it circuit checks just fine as well.
ForbiddTV The main reason why I bought it was because Wikipedia made it seem to me that this model was the only one that detected both Beta and Gamma and I was also told they are hard to come by as well, but of course Wikiapedia being Wikiapedia they seem to think you need a Geiger counter with a Radiation Survey Meter even though it wouldn't really work with a Radiation Survey Meter because if you're detecting anything on the Radaiation Survey Meter the counter wouldn't even work anyways. But seeing from your other videos I can tell this model is not the only one that tests for both. I don't want to seem that im that kind of person that just buys Geiger Counters or Radiation Survey Meters because of Fukashima or something I've always been interested in radiation detection devices because I find them very interesting and also to count for the fact that I like old technology.
SixR That's partly true. Of all the Civil Defense era survey meters, that is the only model that will detect both beta and gamma radiation. However, virtually any geiger counter will detect both beta and gamma at low (not dangerous) levels.
ForbiddTV I can agree with that as you said in some of your videos, toy, life or death.
I was having an issue with a 700.. I was metering some rocks and it started jumping off the scales.. I had the headphones in and it made a funny sound acting like i was standing in Chernobyl or something.. Well I took the batteries out and put em back in and it worked fine.. Any ideas what caused it? Also LOVE the videos keep up the good work
No, I don't know.
I have a victoreen 717 model that works but i cant zero it
MAUSER CATAHOULA If a new battery doesn't fix it then you need some professional service.
Do you work for civil defense?
Civil Defense has been gone since the mid 80's.
@@ForbiddTV Oh sorry about that. I've seen some of your videos they're very interesting and I have learned a lot. Do you live in Georgia?
No, but I have done many shows in Georgia.
I have a Radiological survey meter CD V-700 Model 5, and just yesterday it was working fine. but today when i turned it on i didn't hear any clicks and i didn't see the Needle on the dial move. What is your diagnosis? ( Note, the batteries are brand new )
Lord Dubious 22 It could be a number of things but the number one problem I have with these units is a non-working dial indicator. In your case since you can still hear clicks that's not the problem. It could be the geiger Muller tube or any of the electronics inside the unit itself hard to tell with only the information I have.
ForbiddTV I don't hear any clicks and the dial isn't moving.
When I turn it on I hear a small buzzing sound in the headphones. Just like I did when it worked.
But I have yet to find any apparent problems.
Lord Dubious 22 I'm sorry, I misread your symptoms earlier. In your case I would try to swap out another geiger Muller tube from a working unit (needs no tools) to test that theory if you can find one without having to buy it. They got a lot more expensive since the 2011 Japan accident. If that doesn't work then you got a problem in the electronics somewhere.
My limited experience indicates something bad in the high voltage side, the probe wiring, or the tube itself. I have one that still clicks,but no meter movement. After removing the meter out of the circuit, I discovered the meter was open, or burned out.
Incidentally, do not use a standard old style volt ohm meter, as it has enough voltage to burn out the meter. It's only a 50 ua movement and the measurement voltage can fry it almost instantly. The circuit caries 1V or so fed to the meter thru a 2300 ohm. resistor, so use one of this value or higher to check the meter continuality. But it appears you have a HV problem. Could be the voltage regulator has failed, which will drop Geiger tube voltage dramatically. If you are not electronically inclined, repair services are available on the internet.
Clearly you have a business selling this equipment ? That is why your views regarding nuclear power are so biased in favour of nuclear power.
I'm the guy that tells people the truth - you won't find any Fukushima radiation with any geiger counter or survey meter, = no sale. Duh.
@@ForbiddTV OK - thanks for the clarification.