New Canberra model 40

This area is for discussions involving any fusion related radiation metrology issues. Neutrons are the key signature of fusion, but other radiations are of interest to the amateur fusioneer as well.
Post Reply
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

New Canberra model 40

Post by Richard Hull »

At the HEAS conference I had arranged to take delivery of Bill Kolb's old model 40 Gamma spec.

I got my old 8100 from Bill about 5 years ago. It is pictured in his book on "living with Radiation" near the back of the book.

The model 40 has a few issues with the screen's vertical sync, but I have the IC on order that should fix that problem. Otherwise, the device is really primo.

I will retire my two 8100's, but most likely I will make a single good unit out of the two and use it as a spare.

The model 40 is a much more trouble free unit and has many more features. Still, I will miss the old 8100 leviathon as it was my first super duty gamma spec.

NOTE***

I had a real go-round with the model 40 at first with linearity issues. (one 6 hour day to figure out) I was 255 channels off from channel 100 to channel 1500. I knew the system worked as I had seen Bill use it many times at his house when I had been visiting. I used a NIM pulser to feed directly to the model 40's ADC input and it was as straight and linear as an arrow. This led me to the built in amp. I determined that evidently Bill was using a naked 5" PMT in Charge sensitive mode. I am using a 2" Bicron tube with an attached Bicron preamp that is outputing in voltage mode. I had to change a jumper on the amp board inside the model 40 to let it know that the amp input was in voltage units and not charge units. After this, all was perfect.

Included image is of final calibration against radium found in Ellsworthite mineral sample. 1000 second collect period.

P.S. 10/9/03 FYI... I installed the vertical drive IC on the monitor board (NTE 1289 - commonly avaialble) All problems associated with the display were solved.

Richard Hull
Attachments
Mvc-004f.jpg
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
3l
Posts: 1866
Joined: Sat Jul 07, 2001 3:51 pm
Real name:

Re: New Canberra model 40

Post by 3l »

Hi Richard:

I just won a model 40 on Ebay.
Like yours the vertical drive is out...classic line in the middle.
What company did you get your NTE chip?
Few bidders due to horizontal line on the display.
Looks okay otherwise but will know more when I get it.
Any chance at a manual?
I'm willing to pay.
Just how many folks have mca's anyway?
I would like to hear from ya.
BTW I would like a post of any details no matter how trivial on the model 40.

You really didn't think I'd miss out on all the fun did ya?

Thanks
Larry Leins
Fusor Tech
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: New Canberra model 40

Post by Richard Hull »

The NTE chip is an NTE 1289. I got mine from a local electronics jobber that supplies the line. They are everywhere.

The model 40 can be cantankerous. You will have to have a FIRST RATE, pre-amped 2" or larger NaI crystal and mathced PMT and a super well regulated HV supply. The simple, common, 1 slot NIM hv bias supply is not tight enough. A two or three slot wide precision regulated NIM HV supply IS good enough.

Beware MOST PMT AND CRYSTALS ON EBAY ARE DEFECTIVE.

Of course, the defective part is the crystal ALWAYS. Most crystals are cracked! This is through either abuse like a big ole dent in the xtal housing or that the perfectly good surplus item was stored in an un heated out-building where temperature extremes have caused it to explode and crack or craze internally while still looking perfect externally.

If you can't pre-test your PMT with a functional MCA, you are buying a pig in a poke.

I really don't need a manual for the model 40 as it functions just like my model 8100 and I am familiar with this operation.

What specifically do you need to know? You should get a solid display before investing in anything more. Next would be a superlative supply and finally a PMT and crystal.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
3l
Posts: 1866
Joined: Sat Jul 07, 2001 3:51 pm
Real name:

Re: New Canberra model 40

Post by 3l »

Hi Richard:

I know better than use a xtal from Ebay.
I will goto Oetech for the pmt, housing and NAI Crystal.
I will try to get the video up first for sure but I will have to make up more cabling for the printer and other goodies.
I have to assume an mca is a mca ...
Oh was the memory battery powered like the Canbara 35+?

Happy Fusoring!
Larry Leins
Fusor Tech
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: New Canberra model 40

Post by Richard Hull »

I haven't checked for a battery. Sorry

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
3l
Posts: 1866
Joined: Sat Jul 07, 2001 3:51 pm
Real name:

Re: New Canberra model 40

Post by 3l »

Hi Folks:

I just bought a stack of nim manuals off EBAY.
Lo and behold at the bottom of the stack was a field guide and set of schematics for the model 40 MCA.
I'm still looking for the operating guide tho.

Happy Fusoring!
Larry Leins
Fusor Tech
weaponeer
Posts: 51
Joined: Mon Mar 15, 2004 8:05 pm
Real name:

Re: New Canberra model 40

Post by weaponeer »

Larry,

i just picked up a Series 40 on eBay, it has not arrived yet -- but i expect i will need the schematics when it does...

I was suprised that this went for less than a Series 35. perhaps this due to the channel count, or general feature set ?

Depending on what OETech as documentation wise -- I may be begging a copy of those diagrams from you.

Mark
3l
Posts: 1866
Joined: Sat Jul 07, 2001 3:51 pm
Real name:

Re: New Canberra model 40

Post by 3l »

Hi Mark:

Anything that works always goes higher. My series 40 had a bad display went cheap. People in labs were pretty rabid about the forty. They ran them till they dropped.

Happy Fusoring!
Larry Leins
Fusor Tech
weaponeer
Posts: 51
Joined: Mon Mar 15, 2004 8:05 pm
Real name:

Re: New Canberra model 40

Post by weaponeer »

Larry,

I just got the Series 40 (4202) and it seems to be in working
order. I've not seen such an old bit of hardware this clean. I
had a bit of trouble at first, but reseated all I could and it came
right up. No dust, even in the fan -- this could not have seem
much use.

UPS did alter the alignment of the back panel/ power supply. But
I push carfully until all was "amost" back to spec.

I've not attached a detector yet, but have set the amp gain to
900 and see noise -- messing with the SCA lower limit cuts out
the noise with just a 10th of a turn up from zero.

All keys click loudly, a relay for audio ?? Richard is the the
case ?

All the text is clear -- and the CRT has no burn that I can see
with a flashlight .

One thing is that the noise rolls -- while the text sits rock solid --
is normal -- or a symptom of the NTE chip Richard mentions ? I
expect the answer will be no...

I need to find manuals, OETech has none for the 40. Is there
any chance I might PayPal someone into the trouble of sending
me copies ?

Cheers,

Mark
Attachments
dscn2270.jpg
dscn2271.jpg
weaponeer
Posts: 51
Joined: Mon Mar 15, 2004 8:05 pm
Real name:

Re: New Canberra model 40 -- Escape of the Magic Smoke

Post by weaponeer »

Larry,

I hooked up a probe -- was just getting started -- and puff + a
smell. Power off at once. Spoiled all my fun... grrr.

So far:

With only power board -- all leds light up.

Power + Display -- all pwr leds on.

Power + Disp + CPU -- all pwr leds + single CPU led -- no
display/keyboard yet.

Pwr + Disp + CPU + Memory -- all pwr -- CPU led lights and
goes out. No display/keyboard.

Ahhh.

The ADC board -- has an obvious dead cap near bus
connector -- one of the power pins ? Not plugging this back in
until I get docs && repair.

Picts of ADC attached.

Thanks,

Mark
Attachments
dscn2273.jpg
dscn2272.jpg
Richard Hester
Posts: 1519
Joined: Thu Jul 05, 2001 12:07 am
Real name:

Re: New Canberra model 40 -- Escape of the Magic Smoke

Post by Richard Hester »

This is pretty common with the older Canberra MCAs. The teardrop tantalum caps used for filtering and decoupling don't age well, and tend to short randomly when power is applied. You were lucky if the cap was used at the power supply. You may be able to bring things up by replacing the cap. I would replace as many tantalums as you can with low ESR switcher grade capacitors like the Panasonic FC series, available at Digi-Key. The ESR will possibly be a little lower for the newer electrolytics as compared to the old tantalums. Replace with fairly close to the same capacitance, and the same or greater voltage rating.
3l
Posts: 1866
Joined: Sat Jul 07, 2001 3:51 pm
Real name:

Re: New Canberra model 40 -- Escape of the Magic Smoke

Post by 3l »

Hi Mark:

For thirty bucks ,I'll send you copies of the schematics and field service guide. OETECH would charge you $35 a piece for each.
I would not charge you so much for them except the schematics
are really large (24"x 32") and the binding is thrown in too.
The really neat part is the service guide gives you all the collection subroutines and the accessories this beast supports.
The neat part is a full out line of all aspects of the unit.
The complete theory of how the CPU works and all aspects of DMA workings in the unit...With wave forms!

I was working on putting these manuals on a CDrom along with the thirty five schematics I've got.

Happy Fusoring!
Larry Leins
Fusor Tech
weaponeer
Posts: 51
Joined: Mon Mar 15, 2004 8:05 pm
Real name:

Re: New Canberra model 40 -- Escape of the Magic Smoke

Post by weaponeer »

Larry,

Thats more than fair. Email me and details as to PayPal, etc.

I look forward to the CD too!

Many Thanks,

Mark.

P.S. I am thinking even if I have to rebuild every board in this
beastie -- this is the way to proceed towards building my own
cheap MCA. Learning by doing...

Others have done it -- so why not...

http://lei.fis.uc.pt/pdfs/Com002.pdf

See other papers by same author.
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: New Canberra model 40 -- Escape of the Magic Smoke

Post by Richard Hull »

Good Luck on getting the 40 back up. Just replace the caps as Richard Hester suggests. It is the number one problem with all Canberra Models.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
Richard Hester
Posts: 1519
Joined: Thu Jul 05, 2001 12:07 am
Real name:

Re: New Canberra model 40 -- Escape of the Magic Smoke

Post by Richard Hester »

I have a Canberra Series 30 that also seems to have firecrackers instead of tantalum capacitors.When I have some leisure time, I would like to give it a once-over. My place seems to be a hospice for ailing MCAs these days. I have four of them, and none of them are really working right. The most interesting one is a Tracor MCA that is a full face plug-in for one of the old 70's Tektronix scope mainframes. It's the power supply in the scope that is ailing. Tek makes wonderful scopes, but I do have to wonder about their power supplies after seeing the schematic in the service manual. The +30 supply acts as a reference for all the other supplies, so if that one goes sour, all the others follow suit. As luck would have it, it's the +30V that's on the blink. The pass transistors are all wedged in to the chassis supporting frame for heat sinking, so it's going to be a load of fun digging out the offending transistor for replacement.
3l
Posts: 1866
Joined: Sat Jul 07, 2001 3:51 pm
Real name:

Re: New Canberra model 40 -- Escape of the Magic Smoke

Post by 3l »

Hi Richard:

It's a jungle in there.
Do you know of any manufactuer that makes a Canberra motherboard extender board?
Having the board above the MCA frame would be very useful in doing operational tests.
It could be built from scratch I guess.

Happy Fusoring!
Larry Leins
Fusor Tech
weaponeer
Posts: 51
Joined: Mon Mar 15, 2004 8:05 pm
Real name:

Re: New Canberra model 40 -- Escape of the Magic Smoke

Post by weaponeer »

Larry,

As I mentioned in an email to you, I picked up a set of the
extenders -- I will get some pics up soon. With the exception of
the shielding (same ground rails as on the boards themselves)
and the extender for the DB25 off the LV power
board. I think these would be easy to build up.

I might lend mine out, but the way this is going so far -- they will
either see weekly use -- or go up on eBay with all the rest of this
nonsense once I've fixed it all (in one giant lot -- or knot)-- and
I'll go buy a brand new MCA.

The other thing of note is a dead Series 35 arrived yesterday,
after a "prolonged" eBay wait, the longest in 5 years...

I have noticed so far that the power supply board is identical to
the 40, and it seems the ADC is also the same.

The display and processor sections are miles apart in design.

I've not looked at the memory boards in detail yet. But the 35
has an I/O option board that the 40 does not -- I wonder if it will
swap over ?

Richard, it seems the PROMS would be a weak link in all of this
effort to keep these beasties alive -- I plan to copy the 40's -- do
you know if these can still be had from Canberra ? This 35, I
expect has the MCA version of CJD, as all the labels have
fallen off the chip windows -- and the top has been off for eons --
It just may not know it's an MCA anymore...

Cheers,

Mark
User avatar
Richard Hull
Moderator
Posts: 14992
Joined: Fri Jun 15, 2001 9:44 am
Real name: Richard Hull

Re: New Canberra model 40 -- Escape of the Magic Smoke

Post by Richard Hull »

I would hope that Canberra maintains a small stock of the proms. It takes pretty intense light for a long period to upset a prom. They are probably OK sealed up in the MCA, labels or not.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
weaponeer
Posts: 51
Joined: Mon Mar 15, 2004 8:05 pm
Real name:

Re: New Canberra model 40 -- Pics of the extender cards

Post by weaponeer »

Here they are -- the two slot, single slot, power supply, and -- the
very odd cable that goes with the power supply extender.

To day I moved the series 40 into a (un-dinged) series 35
chassis, backplane and all. The whole operation took only
about 3 hours. The series 35 has all the holes for the 40
faceplace & keyboard, as well as the front panel.

While all the boards seem compatable (pay attention to your
EPROM versions) the backplane in the 35 is a series D, while
the 40 has a series E.

Still not working, but getting closer. When Larry's docs are
here, it will go swimmingly.

Mark
Attachments
dscn2389.jpg
dscn2388.jpg
dscn2387.jpg
dscn2386.jpg
3l
Posts: 1866
Joined: Sat Jul 07, 2001 3:51 pm
Real name:

Re: New Canberra model 40 -- Pics of the extender cards

Post by 3l »

Hi Mark:

Those are very rare now.
Many pc cards and computer motherboards are being ground up for the gold.
It's a work of art.
I wonder If I can rent them for awhile LOL!

Happy Fusoring!
Larry Leins
Fusor Tech
ChrisSmolinski
Posts: 147
Joined: Thu Jun 13, 2002 2:46 pm
Real name:
Contact:

Re: New Canberra model 40 -- Pics of the extender cards

Post by ChrisSmolinski »

larry leins wrote:
> Hi Mark:
>
> Those are very rare now.
> Many pc cards and computer motherboards are being ground up for the
gold.
> It's a work of art.
> I wonder If I can rent them for awhile LOL!

And I'd like to rent them after Larry! ;-)

I'm knee-deep in connecting an 8076 ADC to a PC at the present. I *think* I
can make it work. Famous last works.
David D Speck MD
Posts: 129
Joined: Sat Jan 26, 2008 2:05 pm
Real name: David D. Speck MD
Location: Auburn, NY

Re: New Canberra model 40

Post by David D Speck MD »

I have recently won a Canberra 4203 MCA off eBay. It seems to be fully operational, but It would be very handy to have the operating manual, GPIB Programming instructions, and service schematics for it. Would any of the other lucky owners of these docs be willing to loan me a set for a reasonable consideration?

Thanks,
Dave
David D Speck MD
Posts: 129
Joined: Sat Jan 26, 2008 2:05 pm
Real name: David D. Speck MD
Location: Auburn, NY

Re: New Canberra model 40

Post by David D Speck MD »

Replying to my own post, I sent a query to Canberra about the cost of the manual for the 4203 MCA. I didn't get an eMail response, but to my surprise, I received a copy of the operating manual in the mail today, no charge!. It's not a repair manual, but at least I will be able to operate and program it. It is dated 1983, so it's pretty vintage technology.

If anyone needs a copy, I can PDF it and send it along.

Dave
Post Reply

Return to “Neutrons, Radiation, and Detection (& FAQs)”