Re: [volt-nuts] Newbie here...
Bob, you have to give us the link for the album. When you uploaded the images, the site showed you a link that you need to copy and paste for us. It should be described as share album or something like that. If you had already closed the site, maybe it's still in your browser's history. Cheers, D. On Wed, Feb 26, 2014 at 6:51 AM, Bob Albert bob91...@yahoo.com wrote: I think it's imgur.com On Tuesday, February 25, 2014 9:35 PM, wb6bnq wb6...@cox.net wrote: Hi Bob, As I have never heard of imgur, it would be helpful to provide a proper link to the site. BillWB6BNQ Bob Albert wrote: The pics are in imgur under voltnuts. Bob On Sunday, February 23, 2014 1:47 PM, Bob Albert bob91...@yahoo.com wrote: Pete, Oh yes those Harbor Freight jobs have to be the bargain of the century. And from time to time they even give them away. I am currently checking my time base calibration against WWV at 20 MHz. It's a treat when I can hear them at that frequency so I try to get as close as I can. I usually can get within 0.1 Hz for an error of only 5 ppb, not too shabby. Harder to calibrate voltage though. My IC 10V standards are presumed to be within about .05%, close enough for most work but I want to do better. I do have five of them and can average them but that's subject to systematic errors, since they are all from the same vendor (I think). And that doesn't count aging, important because they are at least 10-15 years old. Bob On Sunday, February 23, 2014 1:17 PM, Pete Lancashire p...@petelancashire.com wrote: Again just my few cents 1 KV on the classics Be very very careful. I was not uncommon for both of these guys to arc over. If you do work with voltages in that space, consider a divider probe. If you do keep playing over about 4 digits at some point you going to need to decided that your absolute measurements are not important or get something like the 3456A calibrated, or the calibrator you have. I've had good luck with one of the few meteorology labs where I live having things calibrated for very little as long as I don't want that little sticker. Once they found out I had a just acquired set of LN 4000s that I wanted to cal, they even let me do it myself. For a few $'s there is a small one man company in Washington state that sells a nicely done set of voltage sources. http://www.voltagestandard.com/ If you add up the parts cost, etc. they are a bargain and well built (not a customer but would be if didn't have the stuff I have). -pete There is a H-F about 1 mile from where I live. One day there were about 20 of the Red DMM in the dumpster, I could not resist. Fixed all except 2 put 2 in the truck and gave the rest away. 90% assembly issues. On Sun, Feb 23, 2014 at 10:21 AM, Bob Albert bob91...@yahoo.com wrote: Well all comments are appreciated and well noted. The 3456A is indeed a Pandora's box and is, as suggested, on the back burner for now. As for the Dana, I have tried all the above. I replaced one IC that seemed to be the root of the trouble, to no avail. The unit is very clean. I spray cooled it when it did its trouble thing and it came back to operation but I haven't been able to find the offending component or solder joint. Power supply seems good throughout. I paid so little for this, and I have so many other units, that I am loath to spend money on a diagram, especially when it is no guarantee of giving me the needed information. Plus, the 300-page HP manual is free for download, so it feels like the tail is wagging the dog here. I will pay attention to the KO4BB site for when the HP manual will appear. But if I need to measure something, I certainly have the tools to do it. If the voltage is above 1 kV I have my Simpson 260 and Triplett 630-NA for that. And I am ashamed to admit, a couple Radio Schlock VOMs. The whole thing here is that I enjoy playing with accurate stuff even though I have no legitimate use for 6-digit voltage measurements. One thing about the HP that appeals is the accurate Ohmmeter. I have a GR 1658 bridge that is very accurate but it doesn't measure at DC, so is cumbersome for inductors, etc. And of course the delightful little toy, the Harbor Freight DVM, is a bargain that can't be approached by 'normal' units. I have several of them and, within their limitations, they are great units. There is a calibrate pot inside that takes care of any ordinary reading errors. And if I blow it up, I pick up another without that dreaded feeling of having broken something valuable. Bob On Sunday, February 23, 2014 3:55 AM, Artek Manuals manu...@artekmanuals.com wrote: Bob et all 1) We have a 1st class scan of the R-D 4200, manual with complete schematics available at a modest price 2) We have a VERY NICE scan (NOT a retread of the poor quality of Agilent scan) 600dpi scans of the schematics full size up to 27x 11 unpieced, again at a very modest price 3) I
Re: [volt-nuts] Newbie here...
This is the link: http://imgur.com/a/8leSW Bob On Wednesday, February 26, 2014 12:53 AM, cheater00 . cheate...@gmail.com wrote: Bob, you have to give us the link for the album. When you uploaded the images, the site showed you a link that you need to copy and paste for us. It should be described as share album or something like that. If you had already closed the site, maybe it's still in your browser's history. Cheers, D. On Wed, Feb 26, 2014 at 6:51 AM, Bob Albert bob91...@yahoo.com wrote: I think it's imgur.com On Tuesday, February 25, 2014 9:35 PM, wb6bnq wb6...@cox.net wrote: Hi Bob, As I have never heard of imgur, it would be helpful to provide a proper link to the site. BillWB6BNQ Bob Albert wrote: The pics are in imgur under voltnuts. Bob On Sunday, February 23, 2014 1:47 PM, Bob Albert bob91...@yahoo.com wrote: Pete, Oh yes those Harbor Freight jobs have to be the bargain of the century. And from time to time they even give them away. I am currently checking my time base calibration against WWV at 20 MHz. It's a treat when I can hear them at that frequency so I try to get as close as I can. I usually can get within 0.1 Hz for an error of only 5 ppb, not too shabby. Harder to calibrate voltage though. My IC 10V standards are presumed to be within about .05%, close enough for most work but I want to do better. I do have five of them and can average them but that's subject to systematic errors, since they are all from the same vendor (I think). And that doesn't count aging, important because they are at least 10-15 years old. Bob On Sunday, February 23, 2014 1:17 PM, Pete Lancashire p...@petelancashire.com wrote: Again just my few cents 1 KV on the classics Be very very careful. I was not uncommon for both of these guys to arc over. If you do work with voltages in that space, consider a divider probe. If you do keep playing over about 4 digits at some point you going to need to decided that your absolute measurements are not important or get something like the 3456A calibrated, or the calibrator you have. I've had good luck with one of the few meteorology labs where I live having things calibrated for very little as long as I don't want that little sticker. Once they found out I had a just acquired set of LN 4000s that I wanted to cal, they even let me do it myself. For a few $'s there is a small one man company in Washington state that sells a nicely done set of voltage sources. http://www.voltagestandard.com/ If you add up the parts cost, etc. they are a bargain and well built (not a customer but would be if didn't have the stuff I have). -pete There is a H-F about 1 mile from where I live. One day there were about 20 of the Red DMM in the dumpster, I could not resist. Fixed all except 2 put 2 in the truck and gave the rest away. 90% assembly issues. On Sun, Feb 23, 2014 at 10:21 AM, Bob Albert bob91...@yahoo.com wrote: Well all comments are appreciated and well noted. The 3456A is indeed a Pandora's box and is, as suggested, on the back burner for now. As for the Dana, I have tried all the above. I replaced one IC that seemed to be the root of the trouble, to no avail. The unit is very clean. I spray cooled it when it did its trouble thing and it came back to operation but I haven't been able to find the offending component or solder joint. Power supply seems good throughout. I paid so little for this, and I have so many other units, that I am loath to spend money on a diagram, especially when it is no guarantee of giving me the needed information. Plus, the 300-page HP manual is free for download, so it feels like the tail is wagging the dog here. I will pay attention to the KO4BB site for when the HP manual will appear. But if I need to measure something, I certainly have the tools to do it. If the voltage is above 1 kV I have my Simpson 260 and Triplett 630-NA for that. And I am ashamed to admit, a couple Radio Schlock VOMs. The whole thing here is that I enjoy playing with accurate stuff even though I have no legitimate use for 6-digit voltage measurements. One thing about the HP that appeals is the accurate Ohmmeter. I have a GR 1658 bridge that is very accurate but it doesn't measure at DC, so is cumbersome for inductors, etc. And of course the delightful little toy, the Harbor Freight DVM, is a bargain that can't be approached by 'normal' units. I have several of them and, within their limitations, they are great units. There is a calibrate pot inside that takes care of any ordinary reading errors. And if I blow it up, I pick up another without that dreaded feeling of having broken something valuable. Bob On Sunday, February 23, 2014 3:55 AM, Artek Manuals manu...@artekmanuals.com wrote: Bob et all 1) We have a 1st class scan of the R-D 4200, manual with complete schematics available at a modest price 2) We have a VERY NICE scan (NOT a retread of the
Re: [volt-nuts] Newbie here...
The pics are in imgur under voltnuts. Bob On Sunday, February 23, 2014 1:47 PM, Bob Albert bob91...@yahoo.com wrote: Pete, Oh yes those Harbor Freight jobs have to be the bargain of the century. And from time to time they even give them away. I am currently checking my time base calibration against WWV at 20 MHz. It's a treat when I can hear them at that frequency so I try to get as close as I can. I usually can get within 0.1 Hz for an error of only 5 ppb, not too shabby. Harder to calibrate voltage though. My IC 10V standards are presumed to be within about .05%, close enough for most work but I want to do better. I do have five of them and can average them but that's subject to systematic errors, since they are all from the same vendor (I think). And that doesn't count aging, important because they are at least 10-15 years old. Bob On Sunday, February 23, 2014 1:17 PM, Pete Lancashire p...@petelancashire.com wrote: Again just my few cents 1 KV on the classics Be very very careful. I was not uncommon for both of these guys to arc over. If you do work with voltages in that space, consider a divider probe. If you do keep playing over about 4 digits at some point you going to need to decided that your absolute measurements are not important or get something like the 3456A calibrated, or the calibrator you have. I've had good luck with one of the few meteorology labs where I live having things calibrated for very little as long as I don't want that little sticker. Once they found out I had a just acquired set of LN 4000s that I wanted to cal, they even let me do it myself. For a few $'s there is a small one man company in Washington state that sells a nicely done set of voltage sources. http://www.voltagestandard.com/ If you add up the parts cost, etc. they are a bargain and well built (not a customer but would be if didn't have the stuff I have). -pete There is a H-F about 1 mile from where I live. One day there were about 20 of the Red DMM in the dumpster, I could not resist. Fixed all except 2 put 2 in the truck and gave the rest away. 90% assembly issues. On Sun, Feb 23, 2014 at 10:21 AM, Bob Albert bob91...@yahoo.com wrote: Well all comments are appreciated and well noted. The 3456A is indeed a Pandora's box and is, as suggested, on the back burner for now. As for the Dana, I have tried all the above. I replaced one IC that seemed to be the root of the trouble, to no avail. The unit is very clean. I spray cooled it when it did its trouble thing and it came back to operation but I haven't been able to find the offending component or solder joint. Power supply seems good throughout. I paid so little for this, and I have so many other units, that I am loath to spend money on a diagram, especially when it is no guarantee of giving me the needed information. Plus, the 300-page HP manual is free for download, so it feels like the tail is wagging the dog here. I will pay attention to the KO4BB site for when the HP manual will appear. But if I need to measure something, I certainly have the tools to do it. If the voltage is above 1 kV I have my Simpson 260 and Triplett 630-NA for that. And I am ashamed to admit, a couple Radio Schlock VOMs. The whole thing here is that I enjoy playing with accurate stuff even though I have no legitimate use for 6-digit voltage measurements. One thing about the HP that appeals is the accurate Ohmmeter. I have a GR 1658 bridge that is very accurate but it doesn't measure at DC, so is cumbersome for inductors, etc. And of course the delightful little toy, the Harbor Freight DVM, is a bargain that can't be approached by 'normal' units. I have several of them and, within their limitations, they are great units. There is a calibrate pot inside that takes care of any ordinary reading errors. And if I blow it up, I pick up another without that dreaded feeling of having broken something valuable. Bob On Sunday, February 23, 2014 3:55 AM, Artek Manuals manu...@artekmanuals.com wrote: Bob et all 1) We have a 1st class scan of the R-D 4200, manual with complete schematics available at a modest price 2) We have a VERY NICE scan (NOT a retread of the poor quality of Agilent scan) 600dpi scans of the schematics full size up to 27x 11 unpieced, again at a very modest price 3) I am sorry but we dont have manuals for the EI or Valhalla unit at the moment but I have added them to my watch for these list I have been following your saga on the 3456A repair on the Agilent forum and don't have much to add except to say this is not a trivial unit to troubleshoot because of the overly (IMO) complex nature of the beast . To paraphrase the old nursery rhyme, When they are good they are very very good but when they are bad they are horrid. I'd probably put that one on the back burner till you get more time , patience and experience. Then sit down and a read the theory of operation
Re: [volt-nuts] Newbie here...
Bob et all 1) We have a 1st class scan of the R-D 4200, manual with complete schematics available at a modest price 2) We have a VERY NICE scan (NOT a retread of the poor quality of Agilent scan) 600dpi scans of the schematics full size up to 27x 11 unpieced, again at a very modest price 3) I am sorry but we dont have manuals for the EI or Valhalla unit at the moment but I have added them to my watch for these list I have been following your saga on the 3456A repair on the Agilent forum and don't have much to add except to say this is not a trivial unit to troubleshoot because of the overly (IMO) complex nature of the beast . To paraphrase the old nursery rhyme, When they are good they are very very good but when they are bad they are horrid. I'd probably put that one on the back burner till you get more time , patience and experience. Then sit down and a read the theory of operation section of the manual till you can recite the whole thing by heart..THEN go digging into boards. With a unit this complex there are scores of feedback and reference check loops that it is often difficult to ascertain when troubleshooting what is a root cause and what is an effect of some other defect elsewhere in the circuit ON the erratic Racal unit, by comparison this is an easier unit to repair with a fairly clean layout of the main board. I would start by carefully unplugging and reseating all cable connectors and the Data I/O board, Display board and power supply diode board. next once the unit begins its erratic behavior after warm up, look at ( with a scope ) the AC ripple on the DC +5V and +20V supply buses . Most likely suspects with any unit more than 25 years old ( aren't they all?) are the Electrolytic and Tantalum capacitors followed by solder joints that just need to be re-flowed. Given the lower complexity of the Dana main board the joints could all be re-flowed in 1/2 hour, One other common source of noise are the calibration pots...which need to be turned back and forth a few times to clean the wipers.. of course after this brilliant move you will need to do a complete recalibration of the unit. Good luck Dave ArtekManuals OnceOn 2/23/2014 1:07 AM, Bob Albert wrote: Pete, The EI is in three parts connected by many massive cables. When I say it's pretty close, I mean it agrees with everything else I feel is close. The 3456A has a -12V reference which the EI measures at -12.0026 or so. It uses an oven so it takes a half hour to settle. I have pics of the panel and would post them if I knew how. The Valhalla is actually a good meter but one range has a small problem. The Racal-Dana is unfixable because I can't find a manual, short of spending more than the meter is worth. Those two units are very similar; the main difference is 1) the Valhalla measures AC current and 2) the Dana has a very sensitive DC microammeter such that I can measure diode leakage. I am befuddled by the HP3456A. I have replaced some parts but so far it's not doing its thing. I have the manual but it sucks, not having a proper schematic diagram nor a board trace layout. The Calib Stds unit is nice, a manually operated slideback DC volts only unit, compact and easy to use. Again, no manual available and, in fact, no mention of the company anywhere online. They were in Los Angeles area. The main reason I want to fix these is that I hate owning anything that doesn't work. And I like knowing my meters are accurate as well as precise. I also have some 10V reference ICs that have been around here a few years. They all agree within a few mV. I made a permanent reference out of them with a switch to select each, and they are running whenever I am in the lab. Bob TRIM -- Dave manu...@artekmanuals.com www.ArtekManuals.com --- This email is free from viruses and malware because avast! Antivirus protection is active. http://www.avast.com ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Newbie here...
Well all comments are appreciated and well noted. The 3456A is indeed a Pandora's box and is, as suggested, on the back burner for now. As for the Dana, I have tried all the above. I replaced one IC that seemed to be the root of the trouble, to no avail. The unit is very clean. I spray cooled it when it did its trouble thing and it came back to operation but I haven't been able to find the offending component or solder joint. Power supply seems good throughout. I paid so little for this, and I have so many other units, that I am loath to spend money on a diagram, especially when it is no guarantee of giving me the needed information. Plus, the 300-page HP manual is free for download, so it feels like the tail is wagging the dog here. I will pay attention to the KO4BB site for when the HP manual will appear. But if I need to measure something, I certainly have the tools to do it. If the voltage is above 1 kV I have my Simpson 260 and Triplett 630-NA for that. And I am ashamed to admit, a couple Radio Schlock VOMs. The whole thing here is that I enjoy playing with accurate stuff even though I have no legitimate use for 6-digit voltage measurements. One thing about the HP that appeals is the accurate Ohmmeter. I have a GR 1658 bridge that is very accurate but it doesn't measure at DC, so is cumbersome for inductors, etc. And of course the delightful little toy, the Harbor Freight DVM, is a bargain that can't be approached by 'normal' units. I have several of them and, within their limitations, they are great units. There is a calibrate pot inside that takes care of any ordinary reading errors. And if I blow it up, I pick up another without that dreaded feeling of having broken something valuable. Bob On Sunday, February 23, 2014 3:55 AM, Artek Manuals manu...@artekmanuals.com wrote: Bob et all 1) We have a 1st class scan of the R-D 4200, manual with complete schematics available at a modest price 2) We have a VERY NICE scan (NOT a retread of the poor quality of Agilent scan) 600dpi scans of the schematics full size up to 27x 11 unpieced, again at a very modest price 3) I am sorry but we dont have manuals for the EI or Valhalla unit at the moment but I have added them to my watch for these list I have been following your saga on the 3456A repair on the Agilent forum and don't have much to add except to say this is not a trivial unit to troubleshoot because of the overly (IMO) complex nature of the beast . To paraphrase the old nursery rhyme, When they are good they are very very good but when they are bad they are horrid. I'd probably put that one on the back burner till you get more time , patience and experience. Then sit down and a read the theory of operation section of the manual till you can recite the whole thing by heart..THEN go digging into boards. With a unit this complex there are scores of feedback and reference check loops that it is often difficult to ascertain when troubleshooting what is a root cause and what is an effect of some other defect elsewhere in the circuit ON the erratic Racal unit, by comparison this is an easier unit to repair with a fairly clean layout of the main board. I would start by carefully unplugging and reseating all cable connectors and the Data I/O board, Display board and power supply diode board. next once the unit begins its erratic behavior after warm up, look at ( with a scope ) the AC ripple on the DC +5V and +20V supply buses . Most likely suspects with any unit more than 25 years old ( aren't they all?) are the Electrolytic and Tantalum capacitors followed by solder joints that just need to be re-flowed. Given the lower complexity of the Dana main board the joints could all be re-flowed in 1/2 hour, One other common source of noise are the calibration pots...which need to be turned back and forth a few times to clean the wipers.. of course after this brilliant move you will need to do a complete recalibration of the unit. Good luck Dave ArtekManuals OnceOn 2/23/2014 1:07 AM, Bob Albert wrote: Pete, The EI is in three parts connected by many massive cables. When I say it's pretty close, I mean it agrees with everything else I feel is close. The 3456A has a -12V reference which the EI measures at -12.0026 or so. It uses an oven so it takes a half hour to settle. I have pics of the panel and would post them if I knew how. The Valhalla is actually a good meter but one range has a small problem. The Racal-Dana is unfixable because I can't find a manual, short of spending more than the meter is worth. Those two units are very similar; the main difference is 1) the Valhalla measures AC current and 2) the Dana has a very sensitive DC microammeter such that I can measure diode leakage. I am befuddled by the HP3456A. I have replaced some parts but so far it's not doing its thing. I have the manual but it sucks, not having a proper schematic diagram
Re: [volt-nuts] Newbie here...
Again just my few cents 1 KV on the classics Be very very careful. I was not uncommon for both of these guys to arc over. If you do work with voltages in that space, consider a divider probe. If you do keep playing over about 4 digits at some point you going to need to decided that your absolute measurements are not important or get something like the 3456A calibrated, or the calibrator you have. I've had good luck with one of the few meteorology labs where I live having things calibrated for very little as long as I don't want that little sticker. Once they found out I had a just acquired set of LN 4000s that I wanted to cal, they even let me do it myself. For a few $'s there is a small one man company in Washington state that sells a nicely done set of voltage sources. http://www.voltagestandard.com/If you add up the parts cost, etc. they are a bargain and well built (not a customer but would be if didn't have the stuff I have). -pete There is a H-F about 1 mile from where I live. One day there were about 20 of the Red DMM in the dumpster, I could not resist. Fixed all except 2 put 2 in the truck and gave the rest away. 90% assembly issues. On Sun, Feb 23, 2014 at 10:21 AM, Bob Albert bob91...@yahoo.com wrote: Well all comments are appreciated and well noted. The 3456A is indeed a Pandora's box and is, as suggested, on the back burner for now. As for the Dana, I have tried all the above. I replaced one IC that seemed to be the root of the trouble, to no avail. The unit is very clean. I spray cooled it when it did its trouble thing and it came back to operation but I haven't been able to find the offending component or solder joint. Power supply seems good throughout. I paid so little for this, and I have so many other units, that I am loath to spend money on a diagram, especially when it is no guarantee of giving me the needed information. Plus, the 300-page HP manual is free for download, so it feels like the tail is wagging the dog here. I will pay attention to the KO4BB site for when the HP manual will appear. But if I need to measure something, I certainly have the tools to do it. If the voltage is above 1 kV I have my Simpson 260 and Triplett 630-NA for that. And I am ashamed to admit, a couple Radio Schlock VOMs. The whole thing here is that I enjoy playing with accurate stuff even though I have no legitimate use for 6-digit voltage measurements. One thing about the HP that appeals is the accurate Ohmmeter. I have a GR 1658 bridge that is very accurate but it doesn't measure at DC, so is cumbersome for inductors, etc. And of course the delightful little toy, the Harbor Freight DVM, is a bargain that can't be approached by 'normal' units. I have several of them and, within their limitations, they are great units. There is a calibrate pot inside that takes care of any ordinary reading errors. And if I blow it up, I pick up another without that dreaded feeling of having broken something valuable. Bob On Sunday, February 23, 2014 3:55 AM, Artek Manuals manu...@artekmanuals.com wrote: Bob et all 1) We have a 1st class scan of the R-D 4200, manual with complete schematics available at a modest price 2) We have a VERY NICE scan (NOT a retread of the poor quality of Agilent scan) 600dpi scans of the schematics full size up to 27x 11 unpieced, again at a very modest price 3) I am sorry but we dont have manuals for the EI or Valhalla unit at the moment but I have added them to my watch for these list I have been following your saga on the 3456A repair on the Agilent forum and don't have much to add except to say this is not a trivial unit to troubleshoot because of the overly (IMO) complex nature of the beast . To paraphrase the old nursery rhyme, When they are good they are very very good but when they are bad they are horrid. I'd probably put that one on the back burner till you get more time , patience and experience. Then sit down and a read the theory of operation section of the manual till you can recite the whole thing by heart..THEN go digging into boards. With a unit this complex there are scores of feedback and reference check loops that it is often difficult to ascertain when troubleshooting what is a root cause and what is an effect of some other defect elsewhere in the circuit ON the erratic Racal unit, by comparison this is an easier unit to repair with a fairly clean layout of the main board. I would start by carefully unplugging and reseating all cable connectors and the Data I/O board, Display board and power supply diode board. next once the unit begins its erratic behavior after warm up, look at ( with a scope ) the AC ripple on the DC +5V and +20V supply buses . Most likely suspects with any unit more than 25 years old ( aren't they all?) are the Electrolytic and Tantalum capacitors followed by solder joints that just need to be re-flowed. Given the lower complexity of the Dana
[volt-nuts] Newbie here...
I am the owner of a few fairly accurate and/or precise voltmeters and would like some information if it's available. First, my Electro Instruments model 3000 5-digit antique with Nixie tube readout, and the accessory AC converter. It hasn't been calibrated in decades but seems pretty close. I have no manual. Second is the recently acquired, not working HP 3456A. Struggling with that repair. Third is the Valhalla 4440. I have most of a manual but it differs somewhat from mine. Mine has an issue on one range of volts. Fourth is the Racal-Dana 4200. This works fine but after it warms up for a half hour starts to get erratic. Fifth is a Calibration Standards model DC-110A. No manual. It has some trouble on range overlap. Can anyone help me with any of these units? Documentation, reputation, etc. Photographs supplied if needed. Bob ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Newbie here...
My take HP 3456A - Great meter. Manuals on the web. Has at least one HP custom device that is a problem, other then salvaging from anohter 3456A is unobtanium. The most complex of your collection. Valhalla 4440. Other then for the fun of fixing stuff not worth anything. Racal Dana 4200 Don't know it EI 3000. I don't have a 3000 but do have a lower cost variant. At least to me a collectors item. You say pretty close, pretty close to what ? I believe it was EI that originated feedback in the Zener loop, finally getting rid of the chopper. If anything the reference by now should have settled down :-). Depending on your experience in repairing TM, I'd use the Valhalla as a way to get some. Then get a manual for the 4200 and repair it. Finally dive into the 3456A. Love to see some inside pictures of the EI. -pete On Sat, Feb 22, 2014 at 5:35 PM, Bob Albert bob91...@yahoo.com wrote: I am the owner of a few fairly accurate and/or precise voltmeters and would like some information if it's available. First, my Electro Instruments model 3000 5-digit antique with Nixie tube readout, and the accessory AC converter. It hasn't been calibrated in decades but seems pretty close. I have no manual. Second is the recently acquired, not working HP 3456A. Struggling with that repair. Third is the Valhalla 4440. I have most of a manual but it differs somewhat from mine. Mine has an issue on one range of volts. Fourth is the Racal-Dana 4200. This works fine but after it warms up for a half hour starts to get erratic. Fifth is a Calibration Standards model DC-110A. No manual. It has some trouble on range overlap. Can anyone help me with any of these units? Documentation, reputation, etc. Photographs supplied if needed. Bob ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
Re: [volt-nuts] Newbie here...
Pete, The EI is in three parts connected by many massive cables. When I say it's pretty close, I mean it agrees with everything else I feel is close. The 3456A has a -12V reference which the EI measures at -12.0026 or so. It uses an oven so it takes a half hour to settle. I have pics of the panel and would post them if I knew how. The Valhalla is actually a good meter but one range has a small problem. The Racal-Dana is unfixable because I can't find a manual, short of spending more than the meter is worth. Those two units are very similar; the main difference is 1) the Valhalla measures AC current and 2) the Dana has a very sensitive DC microammeter such that I can measure diode leakage. I am befuddled by the HP3456A. I have replaced some parts but so far it's not doing its thing. I have the manual but it sucks, not having a proper schematic diagram nor a board trace layout. The Calib Stds unit is nice, a manually operated slideback DC volts only unit, compact and easy to use. Again, no manual available and, in fact, no mention of the company anywhere online. They were in Los Angeles area. The main reason I want to fix these is that I hate owning anything that doesn't work. And I like knowing my meters are accurate as well as precise. I also have some 10V reference ICs that have been around here a few years. They all agree within a few mV. I made a permanent reference out of them with a switch to select each, and they are running whenever I am in the lab. Bob On Saturday, February 22, 2014 6:31 PM, Pete Lancashire p...@petelancashire.com wrote: My take HP 3456A - Great meter. Manuals on the web. Has at least one HP custom device that is a problem, other then salvaging from anohter 3456A is unobtanium. The most complex of your collection. Valhalla 4440. Other then for the fun of fixing stuff not worth anything. Racal Dana 4200 Don't know it EI 3000. I don't have a 3000 but do have a lower cost variant. At least to me a collectors item. You say pretty close, pretty close to what ? I believe it was EI that originated feedback in the Zener loop, finally getting rid of the chopper. If anything the reference by now should have settled down :-). Depending on your experience in repairing TM, I'd use the Valhalla as a way to get some. Then get a manual for the 4200 and repair it. Finally dive into the 3456A. Love to see some inside pictures of the EI. -pete On Sat, Feb 22, 2014 at 5:35 PM, Bob Albert bob91...@yahoo.com wrote: I am the owner of a few fairly accurate and/or precise voltmeters and would like some information if it's available. First, my Electro Instruments model 3000 5-digit antique with Nixie tube readout, and the accessory AC converter. It hasn't been calibrated in decades but seems pretty close. I have no manual. Second is the recently acquired, not working HP 3456A. Struggling with that repair. Third is the Valhalla 4440. I have most of a manual but it differs somewhat from mine. Mine has an issue on one range of volts. Fourth is the Racal-Dana 4200. This works fine but after it warms up for a half hour starts to get erratic. Fifth is a Calibration Standards model DC-110A. No manual. It has some trouble on range overlap. Can anyone help me with any of these units? Documentation, reputation, etc. Photographs supplied if needed. Bob ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there. ___ volt-nuts mailing list -- volt-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts and follow the instructions there.
