| T O P I C R E V I E W |
| FBSMatt |
Posted - 10/26/2020 : 11:27:55
Just a simple idea/experiment. I found a couple SBM-14 tubes in my stash, how do I go about installing one in a 500+? |
| 7 L A T E S T R E P L I E S (Newest First) |
| Damien68 |
Posted - 10/27/2020 : 22:41:21
the sbm20 is a little longer than the M4011 it can't simply fits instead. |
| FBSMatt |
Posted - 10/27/2020 : 12:10:47
Just to check (before I go to dig out that box again), will even the SBM-20 fit in the 500+? I just opened it to remove the M4011 and noticed no extra adjustments for the clip clamp thingy(s). What’s the work around if so? |
| Damien68 |
Posted - 10/27/2020 : 11:01:29
like you i just find one seller on ebay.
it should work like an SBM-20 but bigger.
this means that since its detection volume is greater, it will make measurements of the same quality but faster than a single SBM-20.
for example with an SBM-20 it takes 60 minutes to make a measurement with a minimum confidence index. with a tube 2 times bigger it will take 2 times less time, with a tube 4 times bigger 4 times less time
but it is not necessarily a good calculation and it should be better to connect for example 4 SBM-20 in parallel.
it was surely made to monitor background values on sensitive sites or in any case fairly low levels of radiation |
| FBSMatt |
Posted - 10/27/2020 : 08:37:43
quote:
Originally posted by Damien68
SBM-14, I didn't know him, this one is a big one like a "rolling pin" but the GMC-500+ can't supply 1240v for it. 400-500v is OK.
oh well. I’ll just install a SBM-20 then. What calibration factors should I use for it?
Also. If someone could provide info on what the SBM-14 was used in, that would be great as all I can find are a few eBay listings. |
| Damien68 |
Posted - 10/27/2020 : 06:57:30
SBM-14, I didn't know him, this one is a big one like a "rolling pin" but the GMC-500+ can't supply 1240v for it. 400-500v is OK.
|
| FBSMatt |
Posted - 10/26/2020 : 12:42:53
quote:
Originally posted by EmfDev
Need to check voltage compatibility with the 500+. M4011 tube voltage sits around 400V. If the SBM-14 tube is too long, might need to use as external. Need to change calibration parameters also.
The length of them is as about 104mm.
The voltage is the fun bit! They operate at around 1,200V. That’s why I want to experiment with it! I found them in with some NOS SBM-20 tubes I bought to replace my M4011, which broke after fall (rod came loose, so it only operates probably in a curtain orientation). If I can’t get it working, oh well, guess I’ll just install a boring SBM-20 and not the random thing I found in the bottom of an old Soviet brown box that I can’t find any information on. They do operate up to 300 Celsius, so that’s cool I guess. |
| EmfDev |
Posted - 10/26/2020 : 12:25:14
Need to check voltage compatibility with the 500+. M4011 tube voltage sits around 400V. If the SBM-14 tube is too long, might need to use as external. Need to change calibration parameters also. |
