Problem with Canberra Series 30

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Weiss
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Problem with Canberra Series 30

Post by Weiss »

Hello everybody,

Since Yesterday I own a Canberra series 30 MCA. But I've a little Problem. I connected my Bicron Na(I) Scintillation Detector with the MCA. The MCS and MCSR Mode works wonderful. But the PHA mode, doesn't work. I have no count, except of the counts in channel zero, which are marking the time. Also I have only 512 Channels, but in the Manual is written, the there are 1024 channels. Can you help me?

Much greetings,

Daniel Weiss

P.S. I'm sorry for my English, I'm a Student from Germany and my English isn't very well But I hope it will be better soon
richnormand
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Re: Problem with Canberra Series 30

Post by richnormand »

I have (somewhat poor but usable) scans in pdf of the service manual for the series 30 if you are interested.

Also does your dead time indicator shoots to 100% or stays at 0% while counting zero. Mine did that and it turned out to be a adjustment pot in the Wilkensen AD convertor circuit that was open.Indeed the MCS mode worked OK too but not the pha mode.On my old unit I found broken rework wires, blown tantalum capacitors and dry electrolytics in the power supply and the crt display board. Seems to work for about a year between repairs.

I would follow the signal from the input, check overdriven or blown
preamp, board 1 and board 2 (does the adc has input, uld/lld circuits) Was the threshold adjustment modified? Do a quick memory test by pressing the red button on to of board one (if I remember correctly) to see if part of it is missing or the selectron switch had a bad contact. Then put a test pulse from a signal generator in low sensitivity to bypass the pream circuit altogether and check the ad convertor.

Lots of stuff can cause this, you will need a good scope to follow the signal and find where in the process it goes missing. My first test would be to check for power on each board and dirty intermittent contacts and adjustment pots as this was the bulk of my issues.
lightningt5
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Re: Problem with Canberra Series 30

Post by lightningt5 »

Hi I have just goten hold of a 3100. I am in the UK helping several aviation museums deal with their collection of radio active exhibits.

I am also helping with a group looking into this fusion issue.

I am retired from the British Met. Office Met Research flight. they did the same kind'a thing as NCAR Bolder Colarado.

Trying to put together a usable monitoring suite of instruments on a Government pension!!!!

so need all the he;p- there is going.

Rod Barker.
billwcf
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Re: Problem with Canberra Series 30

Post by billwcf »

Rich, I have two model 30's. One is doa and the other exhibits some of the same behaviors as Daniel's. I would greatly appreciate if you would also send me the pdfs; as I am missing a lot of pages in my manual. Thanks. -bill
richnormand
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Re: Problem with Canberra Series 30

Post by richnormand »

Just sent you the whole file about 5 min ago (about 7meg in size). Return message is failure in delivery. So I sent you a short note to let you know and got the same message again. Is your forum email OK? Got your initial email request OK.
billwcf
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Re: Problem with Canberra Series 30

Post by billwcf »

Rich, wfain@embarqmail.com should work unless there is a size limit on my email somehow. Another solution would be to post it to the files section of the forum. Thanks. -bill
richnormand
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Re: Problem with Canberra Series 30

Post by richnormand »

tried that a few years ago and got a message it was too big. should try it again with the "new improved" forum.

To the moderator: is there a file size limit and how big is it?
Jon Rosenstiel
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Re: Problem with Canberra Series 30

Post by Jon Rosenstiel »

In the past I've used one of the many free file uploading / file sharing services.

Here is just one example:
http://www.uploading.com/

Jon Rosenstiel
Weiss
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Re: Problem with Canberra Series 30

Post by Weiss »

Hallo everybody,

thanks to you! At the moment I have no time, so I couldn't test the MCA, but in a few weeks i have time, and i will open the MCA.

Okey, this scentence was grammatically very, very wrong.

Greetings,

Daniel
lightningt5
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Re: Problem with Canberra Series 30

Post by lightningt5 »

Hi

Could you send me the pdf to my email at r.barker@tesco.net.

The 3100 I have has board 5 missing and the module in the back is missing what was its function.
I notice a lead going to the HV led on the front panel was it a HV generator?

jb154


richnormand wrote:
> I have (somewhat poor but usable) scans in pdf of the service manual for the series 30 if you are interested.
>
> Also does your dead time indicator shoots to 100% or stays at 0% while counting zero. Mine did that and it turned out to be a adjustment pot in the Wilkensen AD convertor circuit that was open.Indeed the MCS mode worked OK too but not the pha mode.On my old unit I found broken rework wires, blown tantalum capacitors and dry electrolytics in the power supply and the crt display board. Seems to work for about a year between repairs.
>
> I would follow the signal from the input, check overdriven or blown
> preamp, board 1 and board 2 (does the adc has input, uld/lld circuits) Was the threshold adjustment modified? Do a quick memory test by pressing the red button on to of board one (if I remember correctly) to see if part of it is missing or the selectron switch had a bad contact. Then put a test pulse from a signal generator in low sensitivity to bypass the pream circuit altogether and check the ad convertor.
>
> Lots of stuff can cause this, you will need a good scope to follow the signal and find where in the process it goes missing. My first test would be to check for power on each board and dirty intermittent contacts and adjustment pots as this was the bulk of my issues.
DaveC
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Re: Problem with Canberra Series 30

Post by DaveC »

Daniel -


Your English is much better than my German, that's certain.

Hope you can get your unit operating... Mine is an old 8100 and is "cranky", when unused for a while... almost always, board-edge contacts. So perhaps pulling everything out, carefully, cleaning the contacts (be sure to be grounded for the ESD protection) and re-inserting everything, will help.

Dave Cooper
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dario_tortato
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Re: Problem with Canberra Series 30

Post by dario_tortato »

richnormand wrote:I have (somewhat poor but usable) scans in pdf of the service manual for the series 30 if you are interested.
Hi, if possible, send me a pdf copy of this service manual. I've one Canberra series 30 in repair. Many tanks for all!!
Dario
richnormand
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Re: Problem with Canberra Series 30

Post by richnormand »

Hi Dario,

just saw your post today. I'll retrieve the pdf and put it here.
EDIT: Just tried and got the "file is too big" message.
:-(

Can you send me another email address that would accept about 7Meg of attachments?
You can PM me the info on fusor mail.
richnormand
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Re: Problem with Canberra Series 30

Post by richnormand »

Just sent you the pdf via your email.
Let me know if you dont get it OK.
Cheers.
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dario_tortato
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Re: Problem with Canberra Series 30

Post by dario_tortato »

Hi Richard,
Update: on my unit, power supply ok but no video. I checked and there is a problem in the transistor that drives the high voltage transformer (Q414).
I tried to replace it with another PNP that I had (MJ2955). Now picture appears but not sharp and not fill the screen. Of the transistor, fixed laterally there is another equal, with only junction BC connected on junction CE of the first (but on the scheme only one transistor is indicated). The original transistors have only the inscription "91278" and do not know what they match. Do you have any idea?
20170204_154043.jpg
richnormand
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Re: Problem with Canberra Series 30

Post by richnormand »

Looks like you do have video but the hv drive of your module looks like it is off and out of focus (difficult to say on the photo).

I'll look in mine to find out what transistor actually is.

I did change Q310 (vertical) on mine but your Q414 is in charge of the horz deflection as well as driving the flyback for the HV. That would also affect focus, linearity and sweep width. Looks like getting proper gain and ce current matters here. Aslo worth looking at CR406, C438 CR103 and CR104 while you are in there. In particular if CR406 is open Q414 will have a difficult life! Check for the 100V at C440.

Remember that horz and vert sweep is at 90 degrees on this. The deflection yoke is installed 90deg from what would be expected in a regular television. Each up/down sweep is one of the 512 channel (that is why you have to go to magnify to see all of the 1024).Thus the "horz" sweeps from top to bottom here. From that point of view then your horz and vert widths are off also. That would be the "vertical" circuit. Do you get a response from the focus adjustment? A problem common to both deflections could be two separate issues or a common issue like power supply. Are the 12V and 30V supplies OK?

Monitor unit is from Elston Electronics Corp. Phelps N.Y. 14532, model DMIO-09B0-119-A39. Check to see if it is the same as in the schematics. They could have different suppliers for this generic module.

Best of luck with it. If you get really stuck I could open my unit and take some voltage measurements and scope waveforms for you.


for reference here are some photos when I power mine.
3) with top indications (seem you have those) and the lines at area of interest . You clear those with the "ROI Clear" below the CRT.
2) The dots are random garbage in the memory. You clear those with the "Clear data" on the main panel.
1) You are then left with the top and bottom lines, initial channel on left and numeric data on top.
Attachments
ready to go
ready to go
data junk
data junk
random ROI and data on startup
random ROI and data on startup
richnormand
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Re: Problem with Canberra Series 30

Post by richnormand »

Too late to edit my previous post:
"I'll look in mine to find out what transistor actually is."
Looks like the same number but difficult to actually read. No clear reference on Google either.
John Futter
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Re: Problem with Canberra Series 30

Post by John Futter »

could be a fast power darlington

you need a good one to measure
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Re: Problem with Canberra Series 30

Post by dario_tortato »

Further work: I replaced a pair of trimmers and some capacitors. Now the image is in place, however, there is another problem .... the image, as time goes by, begins to have a flicker (especially visible in character, a kind of ripple) which becomes more and more visible.
IMG_3557.JPG
IMG_3558.JPG
IMG_3559.JPG
Dario
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Re: Problem with Canberra Series 30

Post by dario_tortato »

This is the link for video: https://www.youtube.com/watch?v=QFi9G9N ... e=youtu.be
the quality is bad, but you see the problem.
I also tried to cool the various components to see if the problem is due to something that works badly or has problems, but nothing changes.

Dario
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Re: Problem with Canberra Series 30

Post by dario_tortato »

Ok, I solved the problem, I'm just stupid. To give the supply voltage in the safety, at the instrument under test, I use a 230/230 isolation transformer and a variac with which the straight edge voltage, starting from a hundred volts, and if there are no problems the increased up to the operating voltage.
This caused the flickering image, I connected the device directly to the supply network, and now the picture is still beautiful and everything ok.
richnormand
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Re: Problem with Canberra Series 30

Post by richnormand »

Nice to hear, congrats.
I guess your next steps is to test the ADC in PHA mode and see if the front-end is OK.
Do you have a scintillator/photomultiplier with a HV supply handy?
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Re: Problem with Canberra Series 30

Post by dario_tortato »

Tanks. Yes, I've this:
IMG_2520.JPG
IMG_3287.JPG
IMG_3478.JPG
Dario
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Re: Problem with Canberra Series 30

Post by richnormand »

Very nice indeed! You seem to have a very nice lab.

Please post your test result once everything is working well.
You could use the K40 1.46MeV line from a box of salt substitute from the grocery store.
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Re: Problem with Canberra Series 30

Post by dario_tortato »

Tank you, no problem, I've many sample source for test. This isn't my first MCA :-)
I hope the weekend to do some testing and then post the results.

Dario
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