Modded SPC900NC

[davy999]

Hi

I have just carried out the mod to the above webcam, but as I havent done any sort of pics with it yet how can i tell if the mod was successful?

I have wxastrocap and k3ccd but not totally sure what i am doing with the programs so any advice would be gratefully received.

[brantuk]

There's lots of advice on the "Astronomiser" website where they do these mods. To test it write something in red on white paper - pop it in a draw - and take some snaps. I seem to remember that's how they test the SC mod's (but don't quote me lol)

[brantuk]

Hmmm ... I was almost right - here's the quote:

"I roughly focus the cam in webcam mode, attach the parallel connector, stick it in a draw, turn the lights off (a red table cloth is over the slight gap in the draw end, hence the colour. This is a 10 sec shot, amp off."

And here's the link : Coxellis AstroImaging

Almost at the bottom of the page - hope that helps

[davy999]

Still no joy (

Checked and rechecked connections.. all seem fine.

IF I have cooked the 4066 chip then surely the webcam would not work at all? It is working as a normal webcam perfectly but this just doesnt want to work with LX.

Tried the thing u suggested, i put it in a box with a note with red writing, seems to just capture an image at the start, ie a snapshot, no long exposure detected.

oh well.. further research required.

[Parallax]

Assuming that you have fitted a parallel connector, what are you connecting that to?

If it's to a normal USB>>parallel adaptor then that wont work - you will need the special adaptor(s) that can be obtained from Astonomiser (although you can make your own).

If it's directly to a parallel port on the computer then I can only suggest that you check all of the wiring/circuit.

Steve

[davy999]

Hi Steve

Connected to LPT1. I put the ground to pin 21 also, even though it says not always required I did this after many many attempts with other things yesterday.

The only thing i notice.. if i look at LX settings in k3ccd when it shows the pins to use it shows LX as fourth from the right.. i.e. pin 3, i have the connection going to pin 2 (with resistor as described), not sure of all the settings in k3ccd but that is puzzling me now.

just as a note.. if i aim the camera at a moving target.. such as a tv picture or something. then with the exposure set at say 10 seconds i would see the tv surround clearly but the actual screen a load of blur.. is that correct?

<-- has been on this problem for 24 hours

[astromerlin]

On my modded SPC when connecting the LX part to software (WXastrocapture) the image brightnens for a second before going back to normal. I modded mine for serial and connected to a usb adapter, but you should get a visual response. Do you have a means to check that the port pin used is switching on or off perhaps a meter or an led with resistor, that way you can check you are using the right pin. If you get no joy and the pin works ok then you have a problem with the mod circuit.

[davy999]

Hi Merlin

Do u mean to plug in the parallel connector whilst wxastro is running?

Also, I do have a meter.. What connections would I use to test, and when would the switch occur, just as I tell it to capture?

[astromerlin]

Hi, Yes I'd test at the p/plug when running WX astrocapture, just set the software to a 1 sec LX and see if pin 2 (if I remember) on the plug should switch on and off at 1 sec interval. If not pin 2 then test the others then you'll know which pin is doing what.

Dont accidently short pins, When I test like this I wrap a bit of tape round the probe so only a small part of the probe lead shows at the end.

I've connected to the wrong pin before, it happens, if you look closely with a magnifyer near the plug pins they have the pin numbers written there. Hard to see though.

[davy999]

Hi Merlin

Will check when i am home later, thanks again for you help!

[davy999]

ok

Put a meter on pin 2. if i put 3 second exposures with 2 second delays it jumps up to approx 4V for the three seconds. then drops to much lower 1 - 2 V for a very short period (dont think 2 seconds) and back up again.

This is on pin 2.

So.. as camera works. and PC sending signal it seems that maybe i fried the chip during assembly.. have a new one due tomorrow so will try again with the mod in a few days.

If this dont work.. i guess astrophotography can wait a while.. scope arrived today so first clear night i will be out learning the scope.

About to read through the manual to ensure i understand all the functions for my first attempt at pointing it in the general vicinity of a star or the moon etc..

[Glider]

Hi, there are several methods for making the LX mod on the WWW, which one have you used, any chance of a link?

"The only thing i notice.. if i look at LX settings in k3ccd when it shows the pins to use it shows LX as fourth from the right.. i.e. pin 3, i have the connection going to pin 2 (with resistor as described), not sure of all the settings in k3ccd but that is puzzling me now."

Just to be clear, you've changed the k3ccd configuration from pin 3 to pin 2 and pin 2 is connected to the pc and you see it going up and down at the camera end? Any chance of a link to the page showing the connections that you have used?

"just as a note.. if i aim the camera at a moving target.. such as a tv picture or something. then with the exposure set at say 10 seconds i would see the tv surround clearly but the actual screen a load of blur.. is that correct?"

Have you done this and this is what you see, or is it what you think you'd expect? If it's the later I'd agree with you that the LX is working.

Perhaps the test in the draw with 'no' light is a little severe, just try it in a room with the curtains drawn and the lights off.

Also, you do have a lens on the camera don't you, focus on some thing across the room with the lights on and LX off, then turn the lights off and run the LX.

I didn't think my mod was working at first because all I was seeing was a lighter shade of pitch black because I had no lens on the front of the camera!!

Just a few ideas, Good luck.

[davy999]

Hi Glider

The connection from LX is on pin 2 of parallel port, left default setting in k3ccd program (shows pin 3), put meter between pin 2 and the 220 ohm resistor, and this voltage jumps up and down for exposure, so this is obviously sending the signal to the camera.

I have the original lens on at the moment whilst I am playing about (to be able to get a picture and keep off any dust whilst I am trying to get it to work.)

When I get a picture that should be 10 seconds, I get a near perfect picture of the screen on the tv, but its an "instant" snapshot picture, definetly no long trails or severe blurring from moving images.. i even tried it by slowly waving my finger in front of the camera, to hopefully see a very fat finger... but it was just my finger.

What I dont understand is that I bent the pins from the connectors as required so they no longer are in contact, I thought this would prevent the camera from taking even a snapshot image.. but it works just as it did before I took it apart.

I used the info from this site for the mod.

Philips SPC900NC uncovered

[astromerlin]

Hi, Same site I used for info, Did you connect the shutter pins to a switch? To first test the shutter is disabled (it has to be to enable the LX to work properly) open the webcams settings and make sure to uncheck auto modes, change the shutter settings (1/25 to 1/500) you should see the image brightness stays the same.

If is does all ok if not the shutter connections are not disabled. check wiring.

Youv'e checked that the computer is outputing a pulse on a pin for LX mode, connect the LX wire to the pin. Arrange the lighting on the webcam so you see a dimmish image and then set the software to LX mode. You should see the image get considerably brighter, you may see a dim frame between light ones (there is a timing value to adjust this out in K3CCDtools but not in WXastrocapture).

If you still get nothing like the above then it's a wiring or chip issue.

Do the checks above and see if you get a result, if not a bit more fault finding.

Hope this helps.

BTW, I found K3CCDtools difficult to setup too, WXastrocapture was more straight forward for initial testing.

[davy999]

one question with wxastro

Do I have to check the box that says use shutter? for long exposure?

[davy999]

ok

Just adjusted the shutter settings.. and when i do with the switch closed it dims as i change it.. with the switch open it does not

I thought the connections to disable are done by bending the pinto pin / pad 10 and pin to pad 8/13 so that they do not enter the black connector. This is definitely the case. both pins are definitely not touching the mating parts inside the connector.

[Glider]

Could it be that you are seeing on pin 2 are the 'normal' levels coming 'out' from the camera, not the LX levels going from the pc to it?

[astromerlin]

Ok, sounds like the shutter switch is working ok, leave it in the position were you get no brightness change this is where you need it for LX to work.

The extra check box in WXastrocapture is for using the amp-off part of the mod if you have built that also. (amp-off greatly reduces the amp glow) I'm doing 2 min subs with no glow which is great but my mount is now the problem still getting elongated stars.

You could have fried the chip electrostaticly. If you do not have an electrostatic wristband, make a temporary one. I use a length of wire with a 1 meg resistor connected, one end goes round the wrist and the other to an earthing point, I have one on my soldering station or you could find a radiator pipe anything that is earthed.

ONLY use this method to place chips in whilst electric is OFF and you and the chip will be ok.

[davy999]

Hi Merlin

There are 2 check boxes in wxastro, one for amp off mod ( I darent even try this until I know LX mod is ok ) and one for LX

Should this be checked to enable the amp off mod?

I think I have tried both ticked and un-ticked to no avail.

Any chance you can confirm something to me as you have the same camera.

I may be mis-understanding how the CCD chip works, i am trying it in normal light, looking at the TV or something else I know is moving. If I put exposure on for say 30 secs and wave my hand in front, would I see my hand all over the image where it has moved to, or does this mod only show itself in almost black conditions with very small points of light?

Think I am getting rather confused now and am just clutching at straws.

I have a new chip on order, along with holding "cage" thingy so i can solder to the cage and then pop the chip in place once all soldering is completed.

Glider - in answer to your question.. no idea. what do you suggest? I could disconnect camera from the PC and put meter on pin two.. but wouldnt know what to do with the other end to complete the circuit to check that the signal is from the pc and not the camera.

Again guys.. thanks for taking the time to respond to my never-ending questions.

[Glider]

Without 'seeing' how you have implemented the mod it's hard to say more. Try another chip and check your circuit is right, no shorts, no loose wires.

Any chance of some pics off say a mobile phone.

On my circuit the camera gives images whether or not the LX wire is connected to the pc because if its not then pull up resistors take over. If the LX wire is connected then driving it from the pc gives long exposures only if the switch is in the right position.

Using a hand held meter might not be fast enough to see the transitions reliably, they are only 10-100ms long and the display may take longer to respond than that.

[astromerlin]

Hi Merlin

There are 2 check boxes in wxastro, one for amp off mod ( I darent even try this until I know LX mod is ok ) and one for LX

Should this be checked to enable the amp off mod?

I think I have tried both ticked and un-ticked to no avail.

Any chance you can confirm something to me as you have the same camera.

I may be mis-understanding how the CCD chip works, i am trying it in normal light, looking at the TV or something else I know is moving.

Yes, 2 check boxes, one reverses the LX pulses from on-off-on to off-on-off. My circuit may be different to yours so I cant advise to wheter to check or uncheck, Leave the amp-off unchecked for now.

Waving your hand and seeing an effect is not a reliable test.

Set the webcam settings to auto off, choose 1/25 shutter (although this really makes no differece it's just good practice) and make sure you have selected 5 frames per sec.

Place webcam in a darkened room, not too dark as you want to see an image of sorts, I placed mine in a box an left enough of a gap to let some light in. set the brightness and gain so you have a dim image.

Try the LX exposure on 1 sec, your image should get brighter. If so the LX is working. if not change the check box in WX astrocapture to change the way the LX is switched as described above.

If you cannot get the thing to work then recheck your wiring and then try the new chip. Make sure that when you place the new chip in it is the correct way round. When I build ic circuits I place chips in a socket, the sockets have a notch at one end as do the chips.

Keeping the notch on the socket to correspond with the chip makes it easier to see orientation when replacing chips in the future.

See how you get on, I'm sure we can get you up and running soon.

[davy999]

ok

Put camera in a box, used the settings you suggested, got the preview image quite dull. The image did not brighten once I started capture so having checked my wiring over and over I am sure the chip is dead.

Just to confirm I have seen a few people comment about an error or lack of clarity in the description regarding pins and pads.

Where it is described to put wire to pin 8/13 I put the wire onto the circuit that has the pins stick out, and the one that said pad onto the board that holds the big black connecter (the one u shave a bit off to allow the ben pins clearance)

This seems to be part of the assembly that some people say can be mis-understood, I assume I did it correctly above.. I know on the pin 10 - pad 10 bits it dont matter as it is only a switch.. but have I done the 8/13 pad - pin bit correctly?

p.s. I am bidding on another spc900 on ebay, so if I break this one I will have another.. if I get this working I can try the amp off mod on the new one (if I get it) (may also think of doing the LX mod using the other method with different chip.. that actually controls the lx on/off without the need for connection to serial port)

[astromerlin]

Just to confirm I have seen a few people comment about an error or lack of clarity in the description regarding pins and pads.

Where it is described to put wire to pin 8/13 I put the wire onto the circuit that has the pins stick out, and the one that said pad onto the board that holds the big black connecter (the one u shave a bit off to allow the ben pins clearance)

I think you may have some connections wrong, the wire connected to pin 9 on the 4066 should go to the 8/13 pin connection on the webcam board that has the socket (ie no pins)

Pin 8 on the 4066 goes to pad 8/13 which is on the webcam board which has the pins on the connector.

[davy999]

well. how daft is that

ok.. gonna get me solder out.. be back soon

I hope its that simple to fix.

<-- crosses fingers

[davy999]

ok

changed them over. rechecked all again.. still no joy..

i put me tools away for now.. i think new chip should be with me tomorrow.. along with socket to protect chip from my soldering! and new resistors etc.. (even though the others check out ok)

Will get myself a small box to fit it in.. we make loads of sizes at work.. sure i can find a nice small one to fit it in and do it properly this time. with space for possible coolling fan in future if required.

I will report back once the new chip is tried then hopefully i can concentrate on my scope for a while ( if the skies ever clear )