#161  
Old 02-08-2016, 06:46 PM
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wasyoungonce (Brendan)
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Absolutely Filip...

What needs to be done for each PCB design is not only a base level noise level but also a readout noise signature. I guess grim would be best to talk to on this. IMHO...wee need to separate the Power supplies to a different sub PCB and shield this. Then make the main PCB. Of course this philosophy needs to be measured...again back to grim and measuring signal noise. Ensure de-coupling caps are as close to the ICs as possible. Look at ceramic caps noise values...especially high value caps...they have an effect depending upon their dialectic.

About the only figure I saw was Grim stating he got down to ~ 4.7eV dark noise value, which is about base value for this sensor and indeed very good for any CMOS sensor. Again readout is an issue.

As said, separating and shielding the power would help a lot but...this needs quantification to which only grim can supply. This is what he mentioned in his original round PCB. He basically said...the noise floor was to high...and did not elaborate. Could be a language issue at play here.

But Luka and I both agree....separate the power from main PCB, shield it, would go a long way to improving the system. We both agree this is an iteration of design (cam 86 rectangle PCB) that will not end here. Oh .....there are other small issues...like ceramic capacitor noise values (from pizeo effect) that can be effected by dielectric used... a whole can of worms...

Brendan
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  #162  
Old 07-08-2016, 11:13 AM
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DMSO ordered, 99.9% Fleabay. I'll probably be removing the sensors and separating them from their carriers this week.
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  #163  
Old 08-08-2016, 02:25 PM
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It's remove sensor time!. Only did one camera...the other later.

Vacuum de-solder made very short work of the pin joints. I wire wrapped the sensor pins to afford some ESD protection for it. This splayed the pins a bit, but they should return when removed.

Would be real nice to keep the sensor metal carrier and sensor together...maybe in the future.
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  #164  
Old 08-08-2016, 05:01 PM
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Annnd so it won't be lonely here's the other ICX453AQ sensor removed.

This is where the Vacuum de-soldering comes into it's own...just seconds per joint. Pity I cannot use it on SMDs

Also had to fix the sensor socket pin row pitch..managed to stuff it up...fixed now. Remember...if a jobs worth doing ...do it twice!...errr in my case 3 or 4 times

edit:
Gawd I need to clean my ESD mat!
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  #165  
Old 09-08-2016, 12:02 AM
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Excellent work
I have been sick in bed for a few days and haven't done anything at all.

Regarding reusing the metal frames for mounting, I am not sure if the frames are the same for D40, D50 and D70. I think you said you had 2x D70. I have D40 and D70, will try to disassemble them soon and compare the frames.
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  #166  
Old 09-08-2016, 08:39 AM
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Hi Luka...hope your on the improve, get well soon.

Yes my cameras were a D70 and D70's. The sensor carrier is so damn well made...shame to toss it considering it would simplify mounting.

I noted even though the vac de-solder worked a treat...it did leave little dags of solder on some legs which need cleaning.

Interesting post on Ukrainian forum by "Wind" regarding sealing and backfill etc. Well worth a look, download the image.rar file. Reading Lukas work on silica gel absorption. Good work, nice to see a critical eye and facts instead of conjecture. The Language translation is difficult enough as is. Despite this they have done some good work.

Meant to say if anyone wanted their sensor removed vac-desoldered...I can do it no problems, literally a 5 min job (apart from disassembly and this only took a few mins) ...only issue is postage.

Had to fix my errors on centreing the sensor and changing the measurements to layer 47 "measure".
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  #167  
Old 11-08-2016, 10:17 AM
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Ok we have the PCB layout pretty much wrapped up and ready, looking at connectors.

We really looked at D sub DB9 mainly due to the fact we could get an IP67 sealed version, ideal for our needs. Pretty much all DB9, sealed D sub (IP67) have the seal on the front face. Given most if not all are around 39mm across the face width...this means we need a space of 39mm to mount this. The bottom of the G106 case is 30mm.

We could not fit it on the bottom of the case without major metal excavations. Nor does fitting it on the lid (or base of case) work given the dimension and where it would sit in relation to the PCB.

About the only connectors I see that will fit and are IP67 are Hirschmann CM series. Here is a 6 way that I think will fit. 19mm dia hole, 23mm centre for mount holes (this might be too big and interfere with the lid flange?), IP67, has a flange seal. We could fit it at the bottom base of the case, "I think" ?

Any ideas appreciated as we are getting closer to making the PCBs, thus we need a decision soon'ish. Jaycar has a similar but in round style, here and here not sure on dimensions though.

I'll upload the Hirschmann CM data sheets to the Cam86 google site.

Brendan

edit:
Actually there is a whole swag of IP67, 5 and 6 way mini sockets at the major suppliers, RS etc. I started to upload some datasheets...but there are too many types. Best to look at them and narrow ideas down. Many will fit out needs, size, IP rating, current and number of ways.

Last edited by wasyoungonce; 11-08-2016 at 11:04 AM.
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  #168  
Old 11-08-2016, 11:01 AM
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Sorry, no time for long messages but I have used Hirose miniature connectors in the past. See here. I may even have a some here.
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  #169  
Old 11-08-2016, 02:24 PM
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Thanks Luka...I think those Hirose use a synthetic/rubber insert...which while might be IP67 would probably not be enough for hermetic seal, or a seal that lasts.

I'm mainly looking at Sockets that have the glass fibre type sealed inserts (that will fit, also have a good current rating ~3A or more), like:
Molex Ultra-Lock M12.
Molex/Brad 120084 series.

Yes some of these have "PCB" type pins one the rear, i'm sure there would be other terminations available...or I cam make a sub-PCB to solder wires and this connector to. "I'm sure these are more that I've missed.

edit:
We could resin pot the end of a connector ourselves....like the Hirose?

Last edited by wasyoungonce; 11-08-2016 at 02:49 PM.
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  #170  
Old 11-08-2016, 09:29 PM
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How about IP68 connectors, here and here.
4A per pin, 5 pins - did we need more than 5? 4 for USB + 1 for peltier power (shared GND).

edit: The real Amphenol part number is just above image, to the left.
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  #171  
Old 13-08-2016, 10:58 PM
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I finally removed the sensor assemblies from my cameras, D70 and D40. Few notes:
  • D70 was soooooo easy, it took less than 5 minutes to have the sensor out and the camera assembled again. Back off, sensor out, back on.
  • D40 has a PCB behind the sensor and this needs to be removed. There is even a wire that needs to be desoldered. The removal is bottom off, back off, PCB off, sensor out, PCB back on, back back on, bottom back on. Similar to Canon 450D.
  • The sensor metal frames are completely different for D70 and D40. So much for reusing the existing metal frames... it would limit the camera choice to one camera only.
  • D40 has a flex PCB. It will be easier to desolder the sensor from it.


Photos attached. Sorry about the quality, I can retake if needed.
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  #172  
Old 14-08-2016, 10:03 AM
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wasyoungonce (Brendan)
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Hi Luka good stuff.

On the D70 sensor...I was looking at the part numbers on the ICs...found EEPROMs, vertical driver IC, shift registers....all the ICs we are substituting. But reverse engineering that sub-PCB...would be a nightmare.

I found the D70 sensor so easy to remove as well. When de-soldering the carrier helps to sink off some of the heat...bonus!
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  #173  
Old 14-08-2016, 10:33 PM
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New corrections on the Ukrainian forum:
Quote:
1. Capacitor C26 need to solder on the contrary in the sense of polarity, painted on board - a plus on the ground.
2. To improve the non-uniformity of brightness Bias horizontally is better to replace C10 0.1 microfarads and R9 generally replaced by a chip inductor. Therefore I introduce some slight changes in the list of elements.
Also new BOM + Gerber is there.

And there is talk now about adding humidity sensor inside the box.
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  #174  
Old 15-08-2016, 08:26 AM
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Thanks Luka I'll have a look.

I have done changes to my lists and Schematic/PCB. But he is talking about the ATMega328P...I think he's saying he programmed it as a ATMega328P with fuse bits as ATMega168P and it was fine. But he also mentions his IC designation "ATmega328" was rubbed off so I'm not sure if its ATMega328P or nor vanilla ATMega328?

I think he's saying its an ATMega328P yet parts list as ATMega328! Sigh! Oh the other attachment was a program update for the ATMega/ATMega328P.

edit:
I asked in CN forum about this and vacuum of sensor!

Received my DMSO this morning. My little friends, the sensors, won't have long to wait before being freed of their earthly carriers.

Last edited by wasyoungonce; 15-08-2016 at 09:19 AM.
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  #175  
Old 15-08-2016, 10:18 AM
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Tapped case holes with M4 x .7. Holes were exactly the correct size for M4 but the screw feels a little loose. Would have liked it with a tighter drill hole.

Had to angle grind one of my M4's to make it a bottoming tap but it all tapped ok right to bottom. I have just over 6mm thread travel. The material probably tapped too easily, it feels a little "weak". So I'll have to be careful tightening screws.

Just using M4 countersunk to feel the threads, have M4 cap head screws on the way.
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  #176  
Old 15-08-2016, 12:35 PM
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Perhaps using nylon M4 screws will be easier on the thread than the stainless ones.
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Old 15-08-2016, 06:37 PM
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Hi Luka..yes thats' a possibility

Just got an answer regarding ATMega328 from Sergiy on CN....it's supposed to be an ATMega328P. The reason is the 328P is more modern and code compiled for 328 can run on 328P but not backwards.

I'm changing schematic now and looking at pin differences. I already had 328P in schematic...probably didn't have footprint of 328!

Sergiy said he didn't know if the sensor could withstand vacuum but they had a sensor cover glass fail moisture got in a destroyed the sensor. They are having issues with dew on the sensors.

edit:
further to this..while I have the correct package there is an issue with the difference between packages pin changes:

Pin ATMega328 ATMega328P
Pin 3 GND PEO/ACO......... A problem with schematic
Pin 6 Vcc PE1................A problem with schematic
Pin 19 ADC6 ADC6/PE2
Pin 22 ADC7 ADC7/PE3

Pin 3 on our schematic/PCB is GND, "0V"
Pin 6 on our Schematic/PCB is VCC, "3.3V".

Yet the ATMega328P data sheets list these pins on the "P" as GND and VCC respectively. TQFP32 package...sigh!

Last edited by wasyoungonce; 15-08-2016 at 06:55 PM.
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  #178  
Old 16-08-2016, 08:22 AM
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A new version PCB and Gerbers has been released on the Ukrainian forum.

Basically they:
Fixed some PCB polarity errors (C26);
Replaced C10 with .1uF;
Replaced R9 with inductor 4.7uF, now called DR7;
Added connection for DHT temp humidity sensor, pin 13 of ATMega328P. Connected to Vcc via new R9 (10k) on bottom of PCB;
Added suitable quick connect connectors for USB and +12V/Gnd inputs.

I'll go over these changes and change our PCB respectively. The SIL for the connector for the power could be an issue. Those 2.54mm connectors are only rated to ~2.5A ...I reckon even less. Jaycar has .156 (4mm) connectors rated to 7A...these might be a better bet. I'll see if I can get them to fit.

EDIT:
Ok got the USB 3 pin SIL on the PCB. I can get the .156" 2way SIL but I'll have some small movements, and I'll look on fleabay/RS to see if I can get a slightly small body version than Jaycar's. I have connectors similar to those used in their PCB but no 3way versions or .156" version.

Last edited by wasyoungonce; 16-08-2016 at 10:12 AM.
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  #179  
Old 16-08-2016, 07:18 PM
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Ok PCB/Schematic updates done uploaded to Google hangout.

Back at the ranch..dinner is served..."Sensor Soup"! Mmmm! Yum!

Soaking sensor in DMSO to free it from alloy carrier. Soak and forget come back in a few days. It apparently falls away.....I hope. I hope I don't come back and the sensors dissolved!
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  #180  
Old 19-08-2016, 09:06 AM
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Icx453aq

The DMSO did it's job, this morning...the ICX453AQ sensor just fell away from the carrier. That was easy! Just some residual gunk to clean away.
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