Thank you for such great video! Would it be possible you could provide a better electronic schematic thru a link? I am trying to debug a currently purchased unit and have issues with the marking on components, etc. Not a hard board to trace/debug but I don’t want to make the situation worse by fixing what is not broken, specially with high voltages Involved) I want to note that is was thru social media recommendation I was directed to your fantastic video. Thanks! *** Nevermind, glitch on my end: Drawing works! ***
@TheMadHatter133716 күн бұрын
Unfortunately, the quality of the image shown at the end of the video is as good as the image is. It’s not a very high resolution image.
@Robert-cd5zr3 ай бұрын
You said your Zener diode stack was backwards. How did you figure this out? Did you align the red dot with the red dot?
@Robert-cd5zr3 ай бұрын
Is it safe then to just throw in regular alkaline D cells in the stock unit? Read someplace that the original batteries were slightly different voltages
@lucaswillis28095 ай бұрын
Awesome video, thanks for posting - you seem to be the sole source of information 412B! I've got one of these open on my bench right now that I've had for a few years and just got around to troubleshooting. The HV supply and regulation work perfectly, but only if I manually close that open frame power relay. I'm pretty sure the time delay relay tube (or its control circuitry) is bad, BUT the part number is illegible so I'm kind of stuck. After I close the main HV relay, both of them operate normally from the HV switch on the front panel, so I think that localizes it to the time delay circuit. Any chance you have a schematic you'd be willing to share, or at least a part number for that time delay tube? Any info would be appreciated. Thanks!
@lucaswillis28095 ай бұрын
Ah, that time delay relay was easier to find than I'd suspected - Amperite 115N030 - even found a datasheet. No luck on a schematic or service manual, though
@TheMadHatter13372 ай бұрын
Sorry for the late reply... I looked for a manual for years, even bought what I thought was it from NASA JPL auction... It was for the 412B that is not adjustable... My assumption is there is no longer a surviving schematic. That being said the regulation system appears to be identical to other 400 series like the 410 or 415, and you can find the manuals online. The reference designation will be different, but using the pictures in the manual you can transcribe. See my HackaDay project for more schematic info.
@zpridgen755 ай бұрын
...I just skipped all of this and built my own.
@TheMadHatter13375 ай бұрын
Yea, geiger counters are trivial with modern technology… the point of the video is to walk people through how it works if they wanna fix their own.
@TheAuriconGroup6 ай бұрын
Collin.... I very much enjoyed your video. I have the exact same make and model. I noticed a rebuild kit for our exact make and model on ebay and bought it. With postage it was about $40.00. It came with all new components. It came with 8 resistors, 5 caps, 2 transistors, and what look like 3 diodes. It also came with a very small matrix of 4 diodes on a very small board ready to install to replace that old tube. My Victoreen CVD 700-6B looks brand new. If you had all the parts on hand like I have, would you go ahead and install them all? I know older caps go bad, so I will replace all of them. And I would replace the three diodes plus the replacement of the tube. If not used, do old resistors go bad? Would you replace them? Also, I fond a document made by Victoreen back in the day that is much better then the manual that came with this unit. It has test points on the schematic and additional troubling shooting tips. Here is a link to a pdf of this document: electrorestore.com/docs/Victor-700-6b-Geiger-Counter-Service-Manual.pdf Again, very much enjoyed your video. I will use it as I take my unit apart and start in on the rebuild. mraroid
@bobbytowesr33876 ай бұрын
You must have had a minute amount of corrosion on one of the connections, when you reassembled it the problem cleared its self
@cashewmilkfan6 ай бұрын
This is so cool! I had no idea these supplies were so interesting inside
@Stelios.Posantzis7 ай бұрын
Nice! I haven't seen anything on youtube (or elsewhere on the internet) about these yet but then again I haven't exactly been looking for details about them. I happen to have the 4kV version (I think) and I'm not sure what I can use it for. I think its current output is even less - much less than 30mA - but I can't be sure right now. For a time I was considering of using it as a power supply for electrostatics but there is really no point (that would be tantamount to the definition of overkill squared or perhaps cubed). Learning here that these were primarily intended for lab use - well, kind of obvious really but then one can never know a priori - kind of clear things up a bit. 2:33 6080 tubes are available as NOS still and their sisters, 6AS7 tubes were still made by Sovtek/Svetlana at least until recently - not sure what the situation is now. You do need two of them so the price seems right, if not a little bit low. 6:53 Ha! Understatement or what?
@Hessijames799 ай бұрын
Thank you for this video. Got a 412B here that apparently needs some calibration. First dial on 1000V, all other on 0 yields 706V. Second dial on 100, all other on 0 yields 70V. So there seems to a a constant factor of 0.7. Any hint on how to calibrate the supply? Can't seem to find a complete manual online.
@TheMadHatter13379 ай бұрын
Sounds similar to my issue… most likely a bad resistor. The calibration pot only adjusts by a few volts.
@Hessijames799 ай бұрын
@@TheMadHatter1337Hi. You are right about the calibration pot. I can adjust about 5 volts. Any hints on how to locate the resistor? I assume it is located in the right third?
@TheMadHatter13379 ай бұрын
I would check the same resistor i show in the video, i think my supply had a similar issue to yours with a 2/3v output from expected. If you are not comfortable working around high voltage, you may want to find someone who is. The voltages on the right sode regulation board should be within 200v of the set point, so a low set-point makes it a bit less dangerous
@Hessijames799 ай бұрын
@@TheMadHatter1337Will do. Thank you!
@Hessijames798 ай бұрын
@@TheMadHatter1337 Thank you for your advice. I measured the resistor (in circuit) and it is 3,5kR :/
@lassitc9 ай бұрын
Great video....
@afnDavid9 ай бұрын
Sprague capacitors with Clorinol oil inside. PCB chemical and quite toxic.
@jordanch6810 ай бұрын
For the Corotron you can usually just leave that in the circuit and install the replacement board in parallel across it. GeoElectronic also sells a volt meter for the HV I have one and it works great.
@xesusdevila752011 ай бұрын
Extremely interesting. That camera definitely qualifies as electronics p*rn! And that floating fan... Thanks a lot for sharing. Keep'em coming please!
@christopherleubner6633 Жыл бұрын
The green box is a specialty integrating transformer. If the hv goes too high it will arc over and kill the counter. If you go with a zener stack make sure to add s buffer capacitor, a resistor, then the zener stack, main limiting resistor. Then the gc cap. Otherwise the ringing pluses will clip and iy may not count right. Fixed hundreds of these things over the years.
@christopherleubner6633 Жыл бұрын
The buzzing with no difflection is usually the crappy HV diode or the sensing transformer arcing, same but with full scale deflation is usually the probe cable.
@KeritechElectronics Жыл бұрын
Oh my goodness, what a thing of beauty and a joy for ever. Watch out for oil leakage on that Sprague cap (its "Clorinol" name suggests polychlorinated biphenyl oil inside) and check out the wires to see if it was not a Fluke... erm, to see if their insulation is not made of asbestos. Sometimes old electronics is full of hazardous materials :(.
@mikefischbein3230 Жыл бұрын
Cool
@DRNEGOLICIS Жыл бұрын
i wonder if its the same on the lionel cdv700 6b
@DKNguyen3.1415 Жыл бұрын
I just got one of these off Ebay byt what output cables are you supposed to use with these? I can't find any BNC cable anywhere near rated for 2kV...at least from reputable suppliers.
@DKNguyen3.1415 Жыл бұрын
Looking around it seems what I need are actually MHV or SHV cables, not BNC?
@TheMadHatter1337 Жыл бұрын
@@DKNguyen3.1415 it depends... Mine had a bnc on the front and a higher voltage one on back... I assume people swapped them out often. That being said, coax bnc when made well can typically handle a few KV. The voltage ratings are often not advertised.
@mohinderkaur6671 Жыл бұрын
Good test of tube
@mohinderkaur6671 Жыл бұрын
very nice power supply and teardown. 8068 looks very similar to a 6BG6 but with much higher power and voltage. possible replacement would be tube color TV Line output tube
@christopher-2000 Жыл бұрын
Hi I'm just Wondering if you have a Link to the ebay page wheee you got your parts from.because I'm having a similar issue with my CDV700 geiger counter
@TheMadHatter1337 Жыл бұрын
I looked, it appears no one sells kits anymore... That being said, they are just 3 high voltage Zener diodes in series (Total of 900V).
@DMF716 Жыл бұрын
I bought the repair kit to do mine maybe next week. I will pay attention to the polarity of the new zener diodes when I install it. Thanks good video.
@armandofretto9917 Жыл бұрын
How can i set the amp widow any load the voltage can be set without any load
@Captain_Char Жыл бұрын
the only part ive changed on mine is the selium rectifier, under the high voltage discharge tube,
@nicolenunya6856 Жыл бұрын
My batteries blew up in mine. Do you know what the replacement pieces that hold the battery are called? Battery box?
@TheMadHatter1337 Жыл бұрын
If your talking about the plastic D Cell battery holders, those are made specific for that... Note - Modern batteries like AA cells can power this fine, you could get 2 sets of 2AA cell battery holders and attach them in pace of the existing 2D holders. You would have to rig up a way to mount them.
@nicolenunya6856 Жыл бұрын
@@TheMadHatter1337 thank you very much. I really appreciate it.
@videosuperhighway7655 Жыл бұрын
The other batteries also power the micro ion chamber as well. There is software to read these. The NFC turns on the bluetooth transmitter. They are current issue. They are good to have for WWIII.
@TheMadHatter1337 Жыл бұрын
I can't find any software to read it that is not from the company with a subscription service. The device will not just pair, it appears to use two factor type of authentication that during pairing it expects a key or cert to complete it
@videosuperhighway7655 Жыл бұрын
@@TheMadHatter1337 that sucks if they ask for subscription instead of allowing the purchase of one copy. Tried messing with the unit. Trying to read the nfc causes the device to show up in bluetooth but no luck messing with it.
@grantnixon9818 Жыл бұрын
Each thousandth of a division is a mrad unit. That makes this unit useful for measuring relatively small doses in my opinion. If neutrons are involved, then the conversion to the radio-protection (stochastic risk) quantity, mrem, is not so simple because it becomes energy-dependent. They’ve calibrated the neutron dose based on a Cf-252 spectrum which is similar to a U-235;or Pu-239 fission spectrum.
@jeremyrileysmith Жыл бұрын
Is there any chance you may be able to assist me in setting up my Replicator 2X with PrusaSlicer? I have been down a rabbit hole for over a week now and can not seem to find the settings I need. If anyone has a profile for this, please please share. I appreciate any assistance from anyone that may be able to help!
@juliench99972 жыл бұрын
Thank you !
@elchimpo90632 жыл бұрын
I'm a bit retarded so I have no idea what any of this means but I have the same problem how do I fix I'm emotionally attached to it
@dhansen72352 жыл бұрын
Where areyou getting info from? I cant find much
@11ccom2 жыл бұрын
More good stuff.
@11ccom2 жыл бұрын
Maybe the ground on the flyback.
@mrT11792 жыл бұрын
24v 200w how many amps.and did it work as it should
@mrT11792 жыл бұрын
And a picture of the underneath of the board would be awesome
@TheMadHatter13372 жыл бұрын
200w/24v=8.3 Amps. Yes it works as expected.
@mrT11792 жыл бұрын
@@TheMadHatter1337 also what terminals did you solder too I’m still a little up in the air on what ones
@TheMadHatter13372 жыл бұрын
@@mrT1179 sorry I sold it actually... So I can't take a picture.
@kllr72 жыл бұрын
Awesome review, exactly what I needed to know. For $50 dollars that's definitely worth the money. We had some $200 end BK Precision power supplies at my last job that were worse than that.
@gregkeller83722 жыл бұрын
Thanks for your help
@raydecker10672 жыл бұрын
Take the rubber gasket off of the bottom of the Geiger tube It may be preventing the tube from going into the socket and working. I always trash them.
@kingcanada25882 жыл бұрын
radium has a half life or 1600 years actually and that's completely incorrect
@ethansav08922 жыл бұрын
Say that to all the bad coronatron tubes rip
@deeaks1002 жыл бұрын
radium has isotopes with half lives ranging from a couple of days to thousands of years. it all depends on which isotope you're talking about.
@TheMadHatter1337 Жыл бұрын
False - There are multiple isotopes... The average decay for a pit is closer to 10-20 years.
@kingcanada2588 Жыл бұрын
@@TheMadHatter1337 radium stays radioactive from 1000s of years
@OH8EFI6 ай бұрын
@@kingcanada2588Plain radium? There's no plain radium inside the tube. It's an isotope of it. But most of the corotron tubes use Nickel-63
@erintyres36092 жыл бұрын
That schematic diagram in the case is labeled at several points to show what voltage to expect when using a plain old 20000 ohms/volt multimeter. A good way to start the repair would be to measure the DC voltage at each of those points. When my meter failed, I had great success with a set of replacement components sold on eBay. The parts and instructions were specific to my particular model of CDV-700. To do this kind of repair, you will need decent soldering skills and lots of desoldering braid. Several of the parts that I removed did not match their specified values. I replaced every supplied component, and in the end the meter worked fine.
@ercost603 жыл бұрын
Very cool. I just got a vintage orange coffee cup which is not Fiestaware but still very radioactive, my cheap counter says 15 uSV. From what I read it's not really dangerous... I drank one cup of coffee from it! But it's just for display and testing now.
@EvilScientist2 жыл бұрын
you might want to be a bit careful encase the uranium leaches out into your drink, or it might flake a tiny bit too. I guess it wouldn't really be dangerous as a one time thing though
@vineet37413 жыл бұрын
Nice
@karvast57263 жыл бұрын
Really a bummer that the tube is burned out,unfortunatly as much as these things are simple enough that they are fairly easy to repair that's the most critical part of the meter.
@terrydavis84513 жыл бұрын
I just bought one of these in working order & good condition if you need Hi-Res photos. I also bought a CDV-715 Ion Chamber that I think the meter was wired in wrong in a botched repair but I dont have the knowledge in electronics to fix at this time. I am learning quickly! Lucky there are great uranium deposits in the area with great crystals. There is a free book on audible called Atomic Adventures that has a chapter on the development of radiation detection meters. I'm thinking of doing the mod to my CDV-700, probably going to wait a few weeks to know what I'm doing. Great videos keep them coming please. If you have a 715 ion chamber please do a video on that circuit.
@TMS51003 жыл бұрын
People carry these in their pocket, which is pretty much direct skin contact. Instead of inches away, it's zero inches.
@Justin-hm4xu3 жыл бұрын
I have the exact same problem
@MrUrbanslasher3 жыл бұрын
I’ve tried twice to build one of these and neither of them work as well as yours. Would love to have schematic.
@TheMadHatter13373 жыл бұрын
This is from like 15 years ago haha. It was just band pass filters with resistors and capacitors triggering Crydom Solid State Relays.
@jackmeoff26203 жыл бұрын
I've been shocked my my Geiger counter it makes your heart beat funny for a minute
@Jesus_paid_it_all3 жыл бұрын
Where at did you get shocked?
@nuclearnerd59074 жыл бұрын
I have a French Geiger counter and it does the same thing.Can somebody offer Me a contact to talk?
Пікірлер
Thank you for such great video! Would it be possible you could provide a better electronic schematic thru a link? I am trying to debug a currently purchased unit and have issues with the marking on components, etc. Not a hard board to trace/debug but I don’t want to make the situation worse by fixing what is not broken, specially with high voltages Involved) I want to note that is was thru social media recommendation I was directed to your fantastic video. Thanks! *** Nevermind, glitch on my end: Drawing works! ***
Unfortunately, the quality of the image shown at the end of the video is as good as the image is. It’s not a very high resolution image.
You said your Zener diode stack was backwards. How did you figure this out? Did you align the red dot with the red dot?
Is it safe then to just throw in regular alkaline D cells in the stock unit? Read someplace that the original batteries were slightly different voltages
Awesome video, thanks for posting - you seem to be the sole source of information 412B! I've got one of these open on my bench right now that I've had for a few years and just got around to troubleshooting. The HV supply and regulation work perfectly, but only if I manually close that open frame power relay. I'm pretty sure the time delay relay tube (or its control circuitry) is bad, BUT the part number is illegible so I'm kind of stuck. After I close the main HV relay, both of them operate normally from the HV switch on the front panel, so I think that localizes it to the time delay circuit. Any chance you have a schematic you'd be willing to share, or at least a part number for that time delay tube? Any info would be appreciated. Thanks!
Ah, that time delay relay was easier to find than I'd suspected - Amperite 115N030 - even found a datasheet. No luck on a schematic or service manual, though
Sorry for the late reply... I looked for a manual for years, even bought what I thought was it from NASA JPL auction... It was for the 412B that is not adjustable... My assumption is there is no longer a surviving schematic. That being said the regulation system appears to be identical to other 400 series like the 410 or 415, and you can find the manuals online. The reference designation will be different, but using the pictures in the manual you can transcribe. See my HackaDay project for more schematic info.
...I just skipped all of this and built my own.
Yea, geiger counters are trivial with modern technology… the point of the video is to walk people through how it works if they wanna fix their own.
Collin.... I very much enjoyed your video. I have the exact same make and model. I noticed a rebuild kit for our exact make and model on ebay and bought it. With postage it was about $40.00. It came with all new components. It came with 8 resistors, 5 caps, 2 transistors, and what look like 3 diodes. It also came with a very small matrix of 4 diodes on a very small board ready to install to replace that old tube. My Victoreen CVD 700-6B looks brand new. If you had all the parts on hand like I have, would you go ahead and install them all? I know older caps go bad, so I will replace all of them. And I would replace the three diodes plus the replacement of the tube. If not used, do old resistors go bad? Would you replace them? Also, I fond a document made by Victoreen back in the day that is much better then the manual that came with this unit. It has test points on the schematic and additional troubling shooting tips. Here is a link to a pdf of this document: electrorestore.com/docs/Victor-700-6b-Geiger-Counter-Service-Manual.pdf Again, very much enjoyed your video. I will use it as I take my unit apart and start in on the rebuild. mraroid
You must have had a minute amount of corrosion on one of the connections, when you reassembled it the problem cleared its self
This is so cool! I had no idea these supplies were so interesting inside
Nice! I haven't seen anything on youtube (or elsewhere on the internet) about these yet but then again I haven't exactly been looking for details about them. I happen to have the 4kV version (I think) and I'm not sure what I can use it for. I think its current output is even less - much less than 30mA - but I can't be sure right now. For a time I was considering of using it as a power supply for electrostatics but there is really no point (that would be tantamount to the definition of overkill squared or perhaps cubed). Learning here that these were primarily intended for lab use - well, kind of obvious really but then one can never know a priori - kind of clear things up a bit. 2:33 6080 tubes are available as NOS still and their sisters, 6AS7 tubes were still made by Sovtek/Svetlana at least until recently - not sure what the situation is now. You do need two of them so the price seems right, if not a little bit low. 6:53 Ha! Understatement or what?
Thank you for this video. Got a 412B here that apparently needs some calibration. First dial on 1000V, all other on 0 yields 706V. Second dial on 100, all other on 0 yields 70V. So there seems to a a constant factor of 0.7. Any hint on how to calibrate the supply? Can't seem to find a complete manual online.
Sounds similar to my issue… most likely a bad resistor. The calibration pot only adjusts by a few volts.
@@TheMadHatter1337Hi. You are right about the calibration pot. I can adjust about 5 volts. Any hints on how to locate the resistor? I assume it is located in the right third?
I would check the same resistor i show in the video, i think my supply had a similar issue to yours with a 2/3v output from expected. If you are not comfortable working around high voltage, you may want to find someone who is. The voltages on the right sode regulation board should be within 200v of the set point, so a low set-point makes it a bit less dangerous
@@TheMadHatter1337Will do. Thank you!
@@TheMadHatter1337 Thank you for your advice. I measured the resistor (in circuit) and it is 3,5kR :/
Great video....
Sprague capacitors with Clorinol oil inside. PCB chemical and quite toxic.
For the Corotron you can usually just leave that in the circuit and install the replacement board in parallel across it. GeoElectronic also sells a volt meter for the HV I have one and it works great.
Extremely interesting. That camera definitely qualifies as electronics p*rn! And that floating fan... Thanks a lot for sharing. Keep'em coming please!
The green box is a specialty integrating transformer. If the hv goes too high it will arc over and kill the counter. If you go with a zener stack make sure to add s buffer capacitor, a resistor, then the zener stack, main limiting resistor. Then the gc cap. Otherwise the ringing pluses will clip and iy may not count right. Fixed hundreds of these things over the years.
The buzzing with no difflection is usually the crappy HV diode or the sensing transformer arcing, same but with full scale deflation is usually the probe cable.
Oh my goodness, what a thing of beauty and a joy for ever. Watch out for oil leakage on that Sprague cap (its "Clorinol" name suggests polychlorinated biphenyl oil inside) and check out the wires to see if it was not a Fluke... erm, to see if their insulation is not made of asbestos. Sometimes old electronics is full of hazardous materials :(.
Cool
i wonder if its the same on the lionel cdv700 6b
I just got one of these off Ebay byt what output cables are you supposed to use with these? I can't find any BNC cable anywhere near rated for 2kV...at least from reputable suppliers.
Looking around it seems what I need are actually MHV or SHV cables, not BNC?
@@DKNguyen3.1415 it depends... Mine had a bnc on the front and a higher voltage one on back... I assume people swapped them out often. That being said, coax bnc when made well can typically handle a few KV. The voltage ratings are often not advertised.
Good test of tube
very nice power supply and teardown. 8068 looks very similar to a 6BG6 but with much higher power and voltage. possible replacement would be tube color TV Line output tube
Hi I'm just Wondering if you have a Link to the ebay page wheee you got your parts from.because I'm having a similar issue with my CDV700 geiger counter
I looked, it appears no one sells kits anymore... That being said, they are just 3 high voltage Zener diodes in series (Total of 900V).
I bought the repair kit to do mine maybe next week. I will pay attention to the polarity of the new zener diodes when I install it. Thanks good video.
How can i set the amp widow any load the voltage can be set without any load
the only part ive changed on mine is the selium rectifier, under the high voltage discharge tube,
My batteries blew up in mine. Do you know what the replacement pieces that hold the battery are called? Battery box?
If your talking about the plastic D Cell battery holders, those are made specific for that... Note - Modern batteries like AA cells can power this fine, you could get 2 sets of 2AA cell battery holders and attach them in pace of the existing 2D holders. You would have to rig up a way to mount them.
@@TheMadHatter1337 thank you very much. I really appreciate it.
The other batteries also power the micro ion chamber as well. There is software to read these. The NFC turns on the bluetooth transmitter. They are current issue. They are good to have for WWIII.
I can't find any software to read it that is not from the company with a subscription service. The device will not just pair, it appears to use two factor type of authentication that during pairing it expects a key or cert to complete it
@@TheMadHatter1337 that sucks if they ask for subscription instead of allowing the purchase of one copy. Tried messing with the unit. Trying to read the nfc causes the device to show up in bluetooth but no luck messing with it.
Each thousandth of a division is a mrad unit. That makes this unit useful for measuring relatively small doses in my opinion. If neutrons are involved, then the conversion to the radio-protection (stochastic risk) quantity, mrem, is not so simple because it becomes energy-dependent. They’ve calibrated the neutron dose based on a Cf-252 spectrum which is similar to a U-235;or Pu-239 fission spectrum.
Is there any chance you may be able to assist me in setting up my Replicator 2X with PrusaSlicer? I have been down a rabbit hole for over a week now and can not seem to find the settings I need. If anyone has a profile for this, please please share. I appreciate any assistance from anyone that may be able to help!
Thank you !
I'm a bit retarded so I have no idea what any of this means but I have the same problem how do I fix I'm emotionally attached to it
Where areyou getting info from? I cant find much
More good stuff.
Maybe the ground on the flyback.
24v 200w how many amps.and did it work as it should
And a picture of the underneath of the board would be awesome
200w/24v=8.3 Amps. Yes it works as expected.
@@TheMadHatter1337 also what terminals did you solder too I’m still a little up in the air on what ones
@@mrT1179 sorry I sold it actually... So I can't take a picture.
Awesome review, exactly what I needed to know. For $50 dollars that's definitely worth the money. We had some $200 end BK Precision power supplies at my last job that were worse than that.
Thanks for your help
Take the rubber gasket off of the bottom of the Geiger tube It may be preventing the tube from going into the socket and working. I always trash them.
radium has a half life or 1600 years actually and that's completely incorrect
Say that to all the bad coronatron tubes rip
radium has isotopes with half lives ranging from a couple of days to thousands of years. it all depends on which isotope you're talking about.
False - There are multiple isotopes... The average decay for a pit is closer to 10-20 years.
@@TheMadHatter1337 radium stays radioactive from 1000s of years
@@kingcanada2588Plain radium? There's no plain radium inside the tube. It's an isotope of it. But most of the corotron tubes use Nickel-63
That schematic diagram in the case is labeled at several points to show what voltage to expect when using a plain old 20000 ohms/volt multimeter. A good way to start the repair would be to measure the DC voltage at each of those points. When my meter failed, I had great success with a set of replacement components sold on eBay. The parts and instructions were specific to my particular model of CDV-700. To do this kind of repair, you will need decent soldering skills and lots of desoldering braid. Several of the parts that I removed did not match their specified values. I replaced every supplied component, and in the end the meter worked fine.
Very cool. I just got a vintage orange coffee cup which is not Fiestaware but still very radioactive, my cheap counter says 15 uSV. From what I read it's not really dangerous... I drank one cup of coffee from it! But it's just for display and testing now.
you might want to be a bit careful encase the uranium leaches out into your drink, or it might flake a tiny bit too. I guess it wouldn't really be dangerous as a one time thing though
Nice
Really a bummer that the tube is burned out,unfortunatly as much as these things are simple enough that they are fairly easy to repair that's the most critical part of the meter.
I just bought one of these in working order & good condition if you need Hi-Res photos. I also bought a CDV-715 Ion Chamber that I think the meter was wired in wrong in a botched repair but I dont have the knowledge in electronics to fix at this time. I am learning quickly! Lucky there are great uranium deposits in the area with great crystals. There is a free book on audible called Atomic Adventures that has a chapter on the development of radiation detection meters. I'm thinking of doing the mod to my CDV-700, probably going to wait a few weeks to know what I'm doing. Great videos keep them coming please. If you have a 715 ion chamber please do a video on that circuit.
People carry these in their pocket, which is pretty much direct skin contact. Instead of inches away, it's zero inches.
I have the exact same problem
I’ve tried twice to build one of these and neither of them work as well as yours. Would love to have schematic.
This is from like 15 years ago haha. It was just band pass filters with resistors and capacitors triggering Crydom Solid State Relays.
I've been shocked my my Geiger counter it makes your heart beat funny for a minute
Where at did you get shocked?
I have a French Geiger counter and it does the same thing.Can somebody offer Me a contact to talk?