PhonoVision Mechanical video recorder Version 3

Centralised area for notes about construction projects. Each project has its own sub-forum. In the sub-forums will be topics relevant to parts of that project (e.g., there might be a topic on motor control). If you start a construction diary, just post in the forum with your project name as the topic, and a moderator will create a sub-forum for your project.

Moderators: Dave Moll, Andrew Davie, Steve Anderson

Re: PhonoVision Mechanical video recorder Version 3

Postby Harry Dalek » Sun Mar 27, 2022 3:55 pm

Well tests yesterday on NBTV i noticed the sine wave on the frame was worse the lower speed i recorded and less so on higher running the stepper on 100 hz twice the speed in fact twice less wave .
Its come down to one last thing the pulley which has a bit of stretch to it, on MK2 fiction drive was used ,i tried a felt matt in case it was vibration as a last resort before trying my last idea which is a major change direct drive ,i can only think the pulley drive with a stretchable pulley is a mistake causing the problem.
I didn't have to make the turntable on mark 2 so any problems here for a home made one didn't happen ,out with the old as they say and i can only give this idea a go and see what happens ,having a think about the mounting looks all possible with out to much change to the rest of it .
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 5363
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: PhonoVision Mechanical video recorder Version 3

Postby Harry Dalek » Fri Apr 08, 2022 8:09 pm

Almost or pretty much ready for another test this time direct drive by rights as in any turntable the motor is mount via rubbers to reduce noise which have not tried yet, i would expect the frequencies from the stepper to make its way if not the recording on play back .
We will see !
What i am more interest in with the coming recordings is how steady the recording is lines lining up in frames reducing any the sine wave to a flat line well that's the plan depends on how good or bad the engineering is .
Every thing evolves and like most of my ideas what it looked like at the start is not how if ends up !
You will notice the HD drive for the platter drive is gone or any belt friction drive ,direct drive now ,i have updated unipolar stepper driver which seems good but i now also have a micro stepper board which i think is more useful for slower speeds than what i am using so testing mine first ,replaced the uln2003 driver for some 80 volt bipolar power transistor that stopped any heating problems driving the stepper .
A few ideas have been scrapped and updated for this ,so today was finishing it off enough for testing still have to mount a reset switch for the stepper board apart from that back to where i was last time i tested .
Well i was never going to try a stepper motor because they are noisy and i have ended up so far trying it :lol: never know unless you try !
Attachments
DSCN7486.JPG
DSCN7487.JPG
DSCN7488.JPG
DSCN7489.JPG
DSCN7491_x264.mp4
(23.14 MiB) Downloaded 285 times
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 5363
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: PhonoVision Mechanical video recorder Version 3

Postby Harry Dalek » Sat Apr 09, 2022 9:21 am

First attempt at a recording with the changes ,i tested 8 sec SSTV again as expected a bit of noise from the stepper and i need to adjust the record arm a bit more but with the crystal clock on 200 hz and motor running switching at 50hz this time the recording and play back platter speed is in sync , this must be good for NBTV later on ,i am going to push it and try a slower SSTV system just see


Here i have just tried scotty 1 and still in sync best colour recordings so far

Attachments
DSCN7497_x264.mp4
(80.48 MiB) Downloaded 523 times
DSCN7498_x264.mp4
(44.19 MiB) Downloaded 524 times
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 5363
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: PhonoVision Mechanical video recorder Version 3

Postby smeezekitty » Sat Apr 09, 2022 11:50 am

Looking great Harry!

Even though you'r making this for SSTV/NBTV use, I'm curious how it performs for speech and music recording
smeezekitty
Just nod and pretend you understand me
 
Posts: 229
Joined: Fri Jan 29, 2010 11:42 am
Location: USA

Re: PhonoVision Mechanical video recorder Version 3

Postby Harry Dalek » Sat Apr 09, 2022 5:28 pm

smeezekitty wrote:Looking great Harry!

Even though you'r making this for SSTV/NBTV use, I'm curious how it performs for speech and music recording


Thanks :)
I will give it a go next time ,i started out making this recording off a transistor radio to see how well voice went then moved on to SSTV next easiest thing ,i also looked into bandwidth of the cartridges around 20khz so voice music fine.
Did a frequency sweep a while back pretty much the range ,i would like to find some thing to out do this as its only half of the sound cards bandwidth feeding video to it be pushing it any thing past 32 line .least its an off the shelf standard record player cartridge used backwards .
I am also interested if it would record digital SSTV NBTV,i never tried last time past standard 32 NBTV and 60 line where i didn't have the bandwidth.
Any way more work onit tomorrow !
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 5363
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: PhonoVision Mechanical video recorder Version 3

Postby Harry Dalek » Thu Apr 14, 2022 6:47 pm

smeezekitty i didn't have time to record audio to file today , i lacked time as today with some circuit work and boring around the house jobs ,i will get to it .
I replaced my play back amplifier with an Lm1875 last amplifier went faulty on me .
Any case a quick test on Scotty 2
Screen 00000.bmp
Screen 00000.bmp (1.2 MiB) Viewed 6775 times

Attachments
DSCN7499_Segment_0_x264.mp4
(35.11 MiB) Downloaded 274 times
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 5363
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: PhonoVision Mechanical video recorder Version 3

Postby Harry Dalek » Thu Apr 21, 2022 7:08 pm

OK where i am at ..I have had to spend my spare time fault finding for the last week and more circuit changes ,more so on the power supply but after seeing the play back on the last recording i needed to track noise problem which funny enough has nothing to do with the stepper motor .
I was getting an intermittent noise signal on the power rails i put it down to bad grounding some where ended up being the transformer one winding had gone bad open it was a dual 20v 0 20v but i was now getting 20v 0 3v just enough to keep the dual supplied amplifier work with noise and fool me .
Lucky for me i have more than one 20v AC supply on this transformer so swapped to it with a few power supply changes every thing nice clean now .
At the same time i again swapped the phono preamplifier amplifier for a Ne5534 Low noise opamp this time built mounted like the others next to the tone arm ,a different circuit using the NE5534 was first tried built on the circuit board up the unit .
Any case all looks ok for further cleaner testing ,before all the trouble i experimented with NBTV at different record speeds and steppers runny at 100HZ double the original speed does improve results ,but i can't say how good it could be till i repeat the recording as i was stuck with a hell of a lot of noise last time around.

Centre top old preamp replaced with Lm1875 and new NE5534 preamp 5 amp regulators mainly for the LM1875 to drive the ceramic cartridge

DSCN7505.JPG


i also wanted Base and treble here as always the lower frequencies will be at a higher amplitude easier to record than the higher frequencies these should help to balance things on play back

DSCN7506.JPG


OH the mess !
DSCN7508.JPG


Get back to testing i hope tomorrow ,the biggest problem with all this is you only have the record time on the disc if its bad another one for the bin :lol:
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 5363
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: PhonoVision Mechanical video recorder Version 3

Postby Harry Dalek » Mon May 02, 2022 7:16 pm

Still at it ! Spent another week with a another change to the pick up cartridge amplifier i am a fussy bugger ! noise wise this ones much cleaner and has a 70khz band width great if my cartridge could do it ,any case i still have to readjust this and that its a lot of trial and error getting it to work correctly if i knock some thing out of whack and you need time to do this .
I did a little quick testing to see how its going as is ,
Martin 1 SSTV colour first


Next the whole reason for all this and still wobbly getting there ,i also have had no time to adjust the levels correctly on record and play back but has promise BBC girl shown ,i have to say recording video on a record is very very hard this is like one of the hardest projects i have ever tried i hope to improved results next time i want to at least surpass MK2 .



I found i was recording my video level toooooo high results below ! i will knock it back next time as mentioned before you only have one try at a time recording like this and if its a dud it s a dud :roll:



OH and smeezekitty i have recorded some sound i will upload next time i have to record it to a wav file,BTW i forgot the stepper speed the motor is running at 50hz if i double this you also get much better results.
Attachments
DSCN7509_x264.mp4
(53.23 MiB) Downloaded 336 times
DSCN7515_x264.mp4
(5.46 MiB) Downloaded 188 times
DSCN7518_x264.mp4
(12.3 MiB) Downloaded 199 times
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 5363
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: PhonoVision Mechanical video recorder Version 3

Postby Harry Dalek » Wed May 04, 2022 6:11 pm

Slight improvement running the platter faster at 120hz on the stepper less wobble video is a bit clearer , when the recording ends you can see the speed its going at .
The lathe seems to be recording the video very well to well having to reduce the volume to the lathe cartridge other wise video results just strong outlines shown .
Knocking video level down a little to much contrast but image is recognisable .
Framing does drift the problems of home made mechanical video recorder players . :roll:
Spike Milligan below our NBTV video test subject and the test card video :wink: OH well see if i can do better next time



Attachments
DSCN7524_Segment_0_x264.mp4
(47.82 MiB) Downloaded 317 times
DSCN7523_x264.mp4
(4.14 MiB) Downloaded 178 times
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 5363
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: PhonoVision Mechanical video recorder Version 3

Postby Viewmaster » Wed May 04, 2022 6:25 pm

Harry, you are getting there, wherever there is. :-)
You are doing much better than results I had from my Edikow machine
recording on wax. CD's cheaper and easier to get
than wax phonograph cylinders too. That's a big bonus.
Your perseverance in this project is amazing. Outstanding.
“One small step for a man,"......because he has Arthritis.
Albert.
User avatar
Viewmaster
Frankenstein was my uncle.
 
Posts: 1306
Joined: Fri Apr 06, 2007 4:50 am
Location: UK Midlands

Re: PhonoVision Mechanical video recorder Version 3

Postby Harry Dalek » Wed May 04, 2022 10:39 pm

Viewmaster wrote:Harry, you are getting there, wherever there is. :-)
You are doing much better than results I had from my Edikow machine
recording on wax. CD's cheaper and easier to get
than wax phonograph cylinders too. That's a big bonus.
Your perseverance in this project is amazing. Outstanding.


OH thank you Albert means a lot coming from you
Not many of us about who have given this a go and on the forum just you and i so far ,your Wax go at it got me interested in trying this as you a few years of trial and error in the making .
How you got wax to record video was pretty amazing not an easy project to try and using cd or dvd plastic is a hell of a lot easier and cheaper and less messy and at the moment still pretty easy to get but i am sure in the years to come cd dvds will be as rare .
Well getting there is meaning i want to push it a bit further than last time .
So far i now understand why i was getting a speed change from recording to play back on MK2 and it comes down to the torque in the asynchronous AC motor the little bit extra embossing a record is enough to slow it down and back to its normal speed on play back ...i corrected that with a belt driven dc motor correcting the AC motor for in sync play back ,Reason i was at first trying geared platter motor and now a Stepper motor direct drive is the way to go .
I was worried at first and stayed away from stepper motors due to noise but funny enough does not seem to be a problem at all and gives me the torque and variable speeds to try ,i may be able to go faster here before the motor clogs something i am looking into .
R.jpg
R.jpg (139.94 KiB) Viewed 6471 times

I am also lucky i went with the ceramic cartridge 20 khz band width and work as a play back or recording device on cd's or dvd's any way .
What also interests me is harmonics i may not try it but its been on my mind for the cartridge question would it work double its working band width ? as we all know trying higher frequencies you need to amplify these greater to match the same amplitude of a lower frequency may be the case here too ?
32line 12.5HZ NBTV and SSTV /Fax is a place to start testing experimenting with this i would also like to try other systems like Bairds original system or my 240 line with 1.5hz system either way those tested have to be done on the multisystem Beast monitor or the devil monitor
DSCN6316_x264.mp4
(3.18 MiB) Downloaded 114 times

I couldn't really try much on the earlier MK2 due to it had external electronics to it, here its all one unit easier to adjust try things that come to mind so i have not finished yet ,i have other projects on my mind but i will work on this a bit more results are getting closer to my wants .
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 5363
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: PhonoVision Mechanical video recorder Version 3

Postby Steve Anderson » Thu May 05, 2022 2:01 pm

Viewmaster wrote:Harry, Your perseverance in this project is amazing. Outstanding.

I can only but concur, in another project that Harry undertook I would have given up. Not Harry. He continued on and eventually got a result he was happy with. I can't recall which project it was, but like this one, there was a lot of trial-and-error...

Steve A.
User avatar
Steve Anderson
"Fester! Don't do that to 'Thing'"
 
Posts: 5357
Joined: Fri Mar 30, 2007 10:54 pm
Location: Bangkok, Thailand

Re: PhonoVision Mechanical video recorder Version 3

Postby Harry Dalek » Thu May 05, 2022 6:30 pm

Steve Anderson wrote:
Viewmaster wrote:Harry, Your perseverance in this project is amazing. Outstanding.

I can only but concur, in another project that Harry undertook I would have given up. Not Harry. He continued on and eventually got a result he was happy with. I can't recall which project it was, but like this one, there was a lot of trial-and-error...

Steve A.


Hi Steve thank you very much for the Nice comments ! I
I think it was either the Beast monitor or MK2 PhonoVision using the old phonograph as a platform to get it working in the first place your thinking of .
Yes a lot of trial and error with some thing mechanical i am making up for not getting meccano as a kid !
I started this to beat my last goal on MK2 which had external components amplifier to drive the cartridge until today i was not happy with the matching of results on 32 line NBTV i have worked out what i did wrong very happy to show results next time i will post i was a bit busy today but i can match and perhaps surpass the last version at least on 32 line and any analog SSTV system perhaps even digital might work .
Funny last time around it was on the play back side speed control problem was my "Achilles' heel" ! this time i was thinking it was either record or play back now i know a simple capacitor missing from a circuit stopping some HF component of the video out ...i recall the problem last time around ...results will be much better ,so far i have also managed to record with the stepper coils run on 200HZ 4 times the original speed ,i need to see here where speed stops improving results and will it help with bandwidth . i think i can get up to 48 line the next goal ..Have to Keep Bairds baby alive :wink:
Last edited by Harry Dalek on Sat May 07, 2022 12:10 am, edited 1 time in total.
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 5363
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: PhonoVision Mechanical video recorder Version 3

Postby Harry Dalek » Fri May 06, 2022 8:23 pm

Here i am running the stepper at 100 hz per coil bit spoilt by the wobble and drift .
Don't centre the disc does not take much to cause this to show up on play back ,as you see a step forward can result in a step back also with a little change here and there to see Oh well back to work see whats up .


Attachments
DSCN7544_x264.mp4
(33.93 MiB) Downloaded 146 times
DSCN7574_x264.mp4
(15.87 MiB) Downloaded 138 times
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 5363
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

Re: PhonoVision Mechanical video recorder Version 3

Postby Harry Dalek » Fri May 13, 2022 5:49 pm

I am swapping over to FM video recording also looking into an adjustment i have made to my PWM so a bit of circuit reconstruction just finished ,was mentioned to me back during the construction of mark 2 this is the way of all video recording really .
I know to improve results the problem of lower frequencies amplitude on the recording cartridge being greater than the high frequency with AM just does not work well for video .
Happy with the scope results from the circuits try and do some embossing lathe tests tomorrow .
The electromagnetic spectrum has no theoretical limit at either end. If all the mass/energy in the Universe is considered a 'limit', then that would be the only real theoretical limit to the maximum frequency attainable.
User avatar
Harry Dalek
"Fester! Don't do that to 'Thing'"
 
Posts: 5363
Joined: Fri Sep 26, 2008 4:58 pm
Location: Australia

PreviousNext

Return to Construction Diaries

Who is online

Users browsing this forum: No registered users and 3 guests

cron