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TRIO CO-1303D CRT flying spot camera tests

PostPosted: Mon Sep 04, 2017 6:11 pm
by Harry Dalek
Very close to hooking every thing up for a low line rate flying spot test run later in the week if every thing cooperates :roll: so starting a new topic here as i am going to use the newly fixed TRIO CO-1303D this was my first oscilloscope i got in early 1980s nice to have it working again its good for this as its small so portable .
Should be good for flying spot testing at least for the lower line rate but i will see how it go's .
There's 2 ways i want to try the easier transparency test card over the screen and a projected screen test card which i would think would really need the PMT .
Next i will put up a raster have to be around the 32 line see how the line and line focus can be adjusted with this.

Re: TRIO CO-1303D

PostPosted: Thu Sep 07, 2017 2:32 pm
by Harry Dalek
Hooking up the scope to the saw tooth circuits and checking the sync ..there's a bit of drift from the main 4046 oscillator which gets better when the thing is running for a bit .
Adjusted the line frequency here on 400 hz 32 line so i can use Gary's software for live testing ..i should be able to test the pmt now and see if can get can pick the scope screen up and display on the 32 line software .
If all works i can move on to 60 line and above on the Thylacine once its video circuit is finished .

Re: TRIO CO-1303D

PostPosted: Sun Sep 10, 2017 3:33 pm
by Harry Dalek
Some very minor results testing today seeing the 4 images per frame i forgot i must have frame sawtooth on a different frame rate i will check this ..
The scope to PMT here is direct off screen ,i did tried a bit of projection to a screen yesterday which needs a lens to work ,once i have one image per frame i will try it again and hope i have a bit of grey scale to things .
PMT here working very low voltage at 295 volts .

youtu.be/qvww5uuFOkk

Re: TRIO CO-1303D

PostPosted: Sun Sep 10, 2017 6:03 pm
by Harry Dalek
Some head scratching today as to why i am getting 4 images live on one laptop .....and on viewing record play back on his pc its correct ...had me wondering at the frame rate was correct and line apart from the drift ..
Any case i can see i have lots of work here .
Play back due to the line frequency drift will play on Garys newer Big picture .

Re: TRIO CO-1303D

PostPosted: Tue Sep 12, 2017 11:17 pm
by Harry Dalek
I made the error thinking i needed to add the sync pulses to the video in this flying spot system ...i do but its done for me via the PMT picking up the raster on the oscilloscope :oops:

Re: TRIO CO-1303D

PostPosted: Fri Sep 15, 2017 1:04 pm
by Harry Dalek
Looking into problems looks like the preamp is over amplifying the PMT signal as shown in tests the other day ... tests today were using half the preamp only the first TLO71 IC results much better .
Clock frequency is drifting so i have a bit of picture roll .. the pick of of the scope grid at 32 line i was not expecting ..
Here's some quick ruff tests

youtu.be/UvzU9ujULpc

youtu.be/n6OHJi_5AEY

youtu.be/EfnYGtsxAfU

Re: TRIO CO-1303D

PostPosted: Fri Sep 15, 2017 8:18 pm
by Robonz
I admire you Harry, always working hard, keep on keeping on! I am sure you will get that vertical sync locked up. Nice work.

Cheers
Keith

Re: TRIO CO-1303D

PostPosted: Fri Sep 15, 2017 8:45 pm
by Harry Dalek
Robonz wrote:I admire you Harry, always working hard, keep on keeping on! I am sure you will get that vertical sync locked up. Nice work.

Cheers
Keith


Thanks Keith :)

Getting there ... i know it can work just a matter of another look at the 3 mhz clock its drifting pretty much a touch but that more than enough to cause the raster roll ,i could use a crystal clock around the frequency this works at but line and frame rates will make it even more off standard more so on the lower line rates if i want to use the software to view i will have a look at what crystals i have handy and what results they will give if used
This was all started to use on the 2 monitors but using the software to view on its lowest standard i can tell how close or off i am so its a tool for me .
So i am thinking about that one as a fix.
i Tried 60 line today but my drift is worse ...lucky Garys software is so good to make up for it ...tried 60 line on 32 just for a synced picture even if it does mean 2 images perframe
Edit ..i just noticed that my local electronics store sells the correct 3.2768MHz crystal that makes life easier !

youtu.be/tSaDBv6Cscg

youtu.be/i3YX9XGHHr8

Re: TRIO CO-1303D

PostPosted: Sat Sep 16, 2017 7:54 pm
by Harry Dalek
Worked on fixing the the clock problem i have replaced the R/C 4046 oscillator with a 4060 3.2768MHz Crystal oscillator i might have to add a trimmer or adjust the capacitors just a touch there's still a very slight roll but much better results and no adjusting needed to the circuit on start up any more .. using the 74hc4060 any case is a easy crystal clock circuit .
i was adjusting the line size and frame size controls on the circuit in the video below if wondering also the line rates frame rates as to what i could show so far ,

youtu.be/5N-k2I9VrTM

Re: TRIO CO-1303D

PostPosted: Mon Sep 18, 2017 7:09 pm
by Harry Dalek
I am trying to get my head around why the image still rolls slowly ,i added a trimmer capacitor to the crystal oscillator and adjust it to dead on 400 Hz ,my meter apparently reads 400.0002 HZ i tried adjusting it off this in case the meter is off which unlikely i could see this is best it is / i had a better sync with my Nipkow camera what the hell ! :roll:
I took a 400 hz signal off pin 12 of the 4040 the ic before the DAC in Steve's circuit ...Testing the square wave on Garys Big Picture alpha version it was steady no roll.
Now i am not adding sync to the video just what the PMT is picking up from the oscilloscope raster .
Viewing the sync on the scope its there not overly strong , i am wondering if the slight delay in the circuits using this system at the moment is causing a slight time delay ..that's all i can think of .
Adjusting scopes position controls video below slow roll real time .

youtu.be/qHj3RPznLkE

Re: TRIO CO-1303D

PostPosted: Thu Sep 21, 2017 11:23 pm
by Harry Dalek
Working with a random 35mm slide today still on 32 line so way to small for the format but i wanted to test how this would go ..results not great but when i got the aspect ratio right on the scope raster position and size can sort of make out the old 60s car and caravan .
I will keep on working on this ..
I am now using both preamp ics and with gain control and this is now out of the first ca3140 video sync mixer the gain over loading is at the last ic ,i think i know what up now and try and fix this.

Re: TRIO CO-1303D

PostPosted: Fri Sep 22, 2017 8:59 pm
by Harry Dalek
Another test with 35mm slides this one at the moment .
i tried it on 64 line and 128 ..i sort of know if they play ok on Doms software.... the video recording must be close to being right.
So i tried 128 line and it plays on the 64 line as 2 images so that must be ok find out in the future when i can play it on the CRT monitor .
As far as the slides i am getting blotchy images not much detail more work needed for sure .

Re: TRIO CO-1303D

PostPosted: Wed Sep 27, 2017 11:21 pm
by Harry Dalek
Still haven't got it just right yet but the video is a touch better more than likely the limits of 32 line flying spot scanning a slide .
The wav files look better ,i tried to day to reconstruct a stronger sync via right from the pre amp as an experiment and then add it to the video sync mixer ,i wanted to see why i was getting still a slow roll of the image in case the digital circuits were delaying it some how .
They play well only really on THE Big Picture V2 alpha.

Re: TRIO CO-1303D

PostPosted: Fri Oct 06, 2017 2:00 pm
by Harry Dalek
Working where i left off the problems that have slowed me down are the crystal clock is running at the correct frequency correct frequencies out of the 4040's but using pin 12 of ic201 400hz for the sync monostable to video sync mixer i get a sync line halfway down the frame using the out put of the DAC its correct again so there's some delay happening also a slight drifting still picture roll slow but there ...so i still need to see if its possible to adjust the crystal clock off its correct frequency a touch so the out put is correct ,i might be able to see with my frequency meter what the delay is from the input 400hz to whats coming out of DAC ic ...as there must be a delay happening never had a crystal oscillator drift like this .

Re: TRIO CO-1303D

PostPosted: Fri Oct 06, 2017 2:13 pm
by Robonz
Hi Harry

I do not fully understand what you are are doing but I can say if your DAC output is a bit delayed compared to the rest of the system then the 100uF output capacitor is likely adding some delay to your signal. It will only be a tiny delay though. To prove it you could add another 100uf capacitor on top of the 100uf and if the delay remains the same it is not the problem.