XY Monitor / Display

Forum for discussion of electronic television. Generally, stuff to do with CRTs and not using mechanical displays.

Re: XY Monitor / Display

Postby Harry Dalek » Sat Aug 25, 2018 9:44 am

FlyMario wrote:So I found a web page that would let me "translate to english" the specifications for my Russian tube. The site is http://zapadpribor.com/5lo38i/

The attachment TubeEnglish1.jpg is no longer available


The attachment TubeEnglish1.jpg is no longer available


Here is yet another page ... http://www.cfp-radio.com/realisations/r ... es-01.html
It can be translated as well so that is nice.


Its good your looking at the Data that's something you have to do as your doing what gos where ....as you see the electostatic tubes are touch harder to understand to power them up .
As you see there's a range minimum to maximum operating voltage range ...so you would not run it at maximum voltages again a bit like the goldilocks zone where the normal operating voltage should be ...notice the high negative and lower positive voltages..in schematic below
I am no expert at these things but i do know now thank's to Steve Andersons help what not to do ..
I have the feeling you want to get this one going ...i really suggest you read all the mistakes i made on the my 3BP1 tube which ended up as the Anderson monitor...it pretty much can be used for a lot of these types of tubes but powered to your tubes operating range .
So at the Start i was just looking around like you how to power the thing so a few pages in i Started to make Steve's circuits.
viewtopic.php?f=17&t=2059

It has the tube pinout. Some words on it are obvious and others not. The X and Y's must be where you aim the beam. Let me guess that heizung is the heater since I know that the heater takes 6.33v. Pin 4 and 10 must be to focus... Oh god... are the anode and cathode holding 1000v. wow. I think I read somewhere there is a min and max... Sometimes the specs seem to contradict each other.

Focus takes 138v to 300v? now I am confused. Pin 10 must not have anything to do with focus. whatever 10 is needs -30v to -90v .

So now I see that 10 must be brightness. puzzled by that voltage.


My tube's negative is at about the 1300 v or so range from memory ,with Steve's voltage multiplier i was tacking on sections to get the correct or close voltage here ...you have to really be safe making testing that ..if you want to touch some thing here touch it with the meter better it die than you ...i don't want to put you off you just have to think safety first ...keep your hands away from it till your 100% sure there's no high voltages in the capacitors.
you will see the power supplies in the links

3BP1 CRT 2.gif
3BP1 CRT 2.gif (12.52 KiB) Viewed 3660 times


That gives you an idea of my 3bp1 tube the positive and negative voltages to the tube this was used as a test circuit , the voltage control on the optocoupler to control the beam ,you should have working scanning and deflection circuits ,with just a raster dot you could burn the screen ..
Note that the positive and negative readings are as shown from ground and from ov cathode ....that is not ground thus the 2 readings .
Don't worry to much yet just read the build a lot of the questions i asked too

CRT tubes sure love different voltages. It says 6.3vac... why? A heater doesn't mind dc right? Isn't that just a element that heats up the tube?


i used dc on the magnetic tubes heater but voltage regulated ,6.3v Ac on the Anderson monitors just use a little 6,3 volt transformer..so yes you can use say a 5 volt dc supply and test your tube the heater should slowly light up .

This is going to be so much fun. Hope I am not too annoying.

Pete


If you do copy the 32 line Anderson monitor only problem i had with a different tube was the 75 volt zener that and a resistor i recall i think had to be changed on the A for Andrew monitor ..again more help from Steve there .
viewtopic.php?f=31&t=2367
viewforum.php?f=31
VCR139A NBTV Initial 1-Model.gif
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Re: XY Monitor / Display

Postby Steve Anderson » Sat Aug 25, 2018 12:51 pm

Unfortunately the datasheet attachments for the Russian CRT "Are no longer available." for some reason.

Yep, CRTs, even the smaller simpler ones, require a lot of external circuitry. The larger ones (5"+) mostly have a PDA (Post Deflection Accelerator) which speeds up the electrons after deflection - this provides a brighter trace at high writing speeds. Some also have a 'trace rotate' function - this is to counter the Earths magnetic field depending on the orientation of the CRT with respect to the Earth. Often though this was done with an external coil.

You can use DC on the heater but there's no point. You have to build a DC power supply instead of just a simple transformer. 6.3V transformers are rare these days but a 6V/1A transformer will be quite OK if the CRT heater current is the usual 300-600mA.

Remember to keep transformers away from the CRT, best place is behind the base connector, or you can put the transformer(s) in a separate power supply box with a 1m 'umbilical'.

Steve A.

Later...also consider using toroidal transformers, they have a much lower external magnetic field and far better regulation - but watt for watt they are more expensive than standard laminated transformers. Photo is a bit 'cruddy', all I could find quickly.

Another advantage of a toroidal is it's easy to add another winding yourself. Wind on (say) 10 turns, measure the voltage from this new secondary, work out the volts-per-turn, divide that into the AC voltage you want, the result is the number of new turns you'll be needing. Don't exceed the total power rating though!

You may need to add more than that, say 10% more for when the transformer has a load, it's easier to take turns off if the voltage is too high, harder to add them.
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Re: XY Monitor / Display

Postby FlyMario » Sat Aug 25, 2018 10:58 pm

Harry Dalek wrote:I have the feeling you want to get this one going ...i really suggest you read all the mistakes i made on the my 3BP1 tube which ended up as the Anderson monitor...it pretty much can be used for a lot of these types of tubes but powered to your tubes operating range .


Nah Harry, I am in no real hurry. I just want to get the details straight before I do anything stupid to my beautiful Russian Tube. I have spent most of my life hugging the 5vdc power rail. So much about AC (although taught in Naval School) is pathetic.

I see you all using transformers (never touched one) with multiple sets if windings obviously for specific uses such as TV. The Hammond transformers seem really expensive. I see 6.3v transformers which most likely were designed for the tube heaters (see I learned something).

A few questions:

(1) If you see a voltage like 6.3v is it always safe to assume it means AC because it does not have VDC? Is that a rule?

(2) when you see 6.3v does that mean 12.6v peak to peak? Or is that 3.15v Peak to Peak? Sorry if that sounds stupid but I know what a sinewave looks like and there should be - and + swing.

Harry Dalek wrote:That gives you an idea of my 3bp1 tube the positive and negative voltages to the tube this was used as a test circuit , the voltage control on the optocoupler to control the beam ,you should have working scanning and deflection circuits ,with just a raster dot you could burn the screen ..


Are you saying that I can burn a dot on my screen very quickly making a simple mistake? My god that is horrible. My Tube is perfect with no marks. I don't want to do that.

I am still puzzled by the fact I have no nipple on the outside of my tube. Do you think I need to wrap something metal around it to go to Flyback or do you think this tube has no flyback. I am not really gotten into the area of flyback yet. Is it supposed to discharge static or something?

When it says voltage 500v to 1100 v. Are we saying anything in that range is fine or we might have to vary this voltage for something to work right?

Ideally I would like to have my circuits run on 12v but I think that is probably going to be way too much trouble. So then I think I would do 110VAC (who knows what it really is...). Obviously I would need a step up transformer.

To move the beam left and right is going to be 660VAC? or 1230v Peak to Peak.

https://www.amazon.com/Isolation-Transf ... dpSrc=srch
That transformer seems like it should be reasonable for this project. I wish it had more specifications because I am wondering if it has a -600v and a +600v which in my head says 1200v. So many of the components need - voltages.

They are saying my tube should last 1000 hours minimum. I actually felt stressed by reading that. Though really, once I make it and play with it a bit I guess that's not bad.

Steve A, wow what a weird transformer. Not sure I have ever seen one.

I used to make electromagnets and actually started thinking would I have to make my own transformer to get the voltages I wanted. Winding my own transformer to get those high voltages.

Pete
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Re: XY Monitor / Display

Postby FlyMario » Sat Aug 25, 2018 11:11 pm

https://youtu.be/VZ98462lnyI

I see this video here and I get hope. It's not some huge transformer. It's in Russian (I believe)... things are on a breadboard. Doesn't make me think someone is going to die easily working with it. Maybe that is my own ignorance.

All of your circuits look reasonable. Though I can't necessarily understand what I am seeing sometimes.

Lets say you are trying to drive the beam left/right up/down and it seems that it would need around 600vac. There must be some incredible mosfet that could handle that many volts being driven by a tiny voltage from arduino driven circuit. For instance if I made a DAC that put out -2v to +2v (or whatever low voltage) into a opto isolator (not to freak me out about blowing my circuit up) into some mosfet that won't explode over 600v.

Pete
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Re: XY Monitor / Display

Postby Harry Dalek » Sun Aug 26, 2018 12:56 am

FlyMario wrote:
Nah Harry, I am in no real hurry. I just want to get the details straight before I do anything stupid to my beautiful Russian Tube. I have spent most of my life hugging the 5vdc power rail. So much about AC (although taught in Naval School) is pathetic.


Well that's a good thing to get it right in your head before rushing into it ....you could always do a like bit at a time ...some time s i thing about a project for a few months before i start ...
Need to think about mounting the tube in some case idea to keep it and you safe as you will want it to be a monitor in time and take all that into account Peter .

I see you all using transformers (never touched one) with multiple sets if windings obviously for specific uses such as TV. The Hammond transformers seem really expensive. I see 6.3v transformers which most likely were designed for the tube heaters (see I learned something).


Its hard to get one transformer to supply the HV heater and 12 volts supplies ,i ended up using a old valve radio transformer for the High voltage and it also has the heater 6.3 volts and used a send transformer for the circuits 12 volts supply .
I just scrap stuff from old gear i find for the transformers in that ,costs a bit to buy new would not be able to do it if i had to do that .
As Steve mentioned best to keep the power supply transformers away form the tube as you don't have a magnetic shielding for this CRT .
If you see my first results the magnetic field is deflecting my raster dot Not good .
A few questions:


Ok

(1) If you see a voltage like 6.3v is it always safe to assume it means AC because it does not have VDC? Is that a rule?


Yes pretty much most valves used this voltage for the heaters and CRT's but not all infact my VCR139 tube is 3 volts so the data came in useful or i might of ended the life of that CRT running it on double voltage .

(2) when you see 6.3v does that mean 12.6v peak to peak? Or is that 3.15v Peak to Peak? Sorry if that sounds stupid but I know what a sinewave looks like and there should be - and + swing.


i think its more like 3,15 3,15 volts

Are you saying that I can burn a dot on my screen very quickly making a simple mistake? My god that is horrible. My Tube is perfect with no marks. I don't want to do that.


YES ....if you have the the tube on correct voltages to focus the raster dot to a point and and have the brightness up its a like a magnifying glass focusing the sun it will burn a hole in the phosphor for good .
Reason to have at least one of the deflection happening .

I am still puzzled by the fact I have no nipple on the outside of my tube. Do you think I need to wrap something metal around it to go to Flyback or do you think this tube has no flyback. I am not really gotten into the area of flyback yet. Is it supposed to discharge static or something?


The reason is voltage you are looking around the 10,000 volts for a magnetic tube more than likely due to its shape short gun wide deflection area ..the electrostatic only needs 700 to 1.500 volts so can be fed via the plug pins ...i think large electrostatic tubes do have a a out side nipple idea higher voltages needed i suppose ...Steve would know for sure on this subject.


When it says voltage 500v to 1100 v. Are we saying anything in that range is fine or we might have to vary this voltage for something to work right?


Pretty much you start low see how it goes but if you happen to be in range above should be fine ...not good to run on maximum .

Ideally I would like to have my circuits run on 12v but I think that is probably going to be way too much trouble. So then I think I would do 110VAC (who knows what it really is...). Obviously I would need a step up transformer.


Its not impossible to run it from 12 volts and a inverter for the HV side but you want a clean DC supply out ..easier to do it from a mains transformer but up to you of cause

To move the beam left and right is going to be 660VAC? or 1230v Peak to Peak.


I recall on mine i think it was a supply 200 to 300 to move the beam on the deflection amplifier from one side to the other but have not looked here at yours .

https://www.amazon.com/Isolation-Transformer-Power-115V-600V/dp/B005T7X4P2/ref=sr_1_4?s=industrial&ie=UTF8&qid=1535197563&sr=1-4&keywords=600v+transformer&dpID=31UYpZ7JJpL&preST=_QL70_&dpSrc=srch
That transformer seems like it should be reasonable for this project. I wish it had more specifications because I am wondering if it has a -600v and a +600v which in my head says 1200v. So many of the components need - voltages.


Looks ok you would be feeding it mains 110v yes .its says 95v is that the primary ? If so the out puts would be a touch higher might be out of range for the heater then ..
a cheaper idea would be 2 back to back 12 volt transformers 2 6.3 volt center windings ...mains to the first secondary to secondary 2nd transformer primary of the 2nd HV out 200 plus AC but the secondary of the first transformer you could get the heater 6.3 volts ...not sure if you were pushing it you could get the 12 volts out here as well ....just need a voltage multiplier for the second transformer primary ...you can get positive and negative HV out of a 2 primary connections
But i would use the same transformers for a back to back idea don't ever mix and match one just heats up ! if they are the same i have never had a problem .

They are saying my tube should last 1000 hours minimum. I actually felt stressed by reading that. Though really, once I make it and play with it a bit I guess that's not bad.


I have a tv from 1962 still working so its pot luck ,every thing has a limit nothing lasts for ever .
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.
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Re: XY Monitor / Display

Postby Harry Dalek » Sun Aug 26, 2018 1:06 am

FlyMario wrote:https://youtu.be/VZ98462lnyI

I see this video here and I get hope. It's not some huge transformer. It's in Russian (I believe)... things are on a breadboard. Doesn't make me think someone is going to die easily working with it. Maybe that is my own ignorance.

All of your circuits look reasonable. Though I can't necessarily understand what I am seeing sometimes.

Lets say you are trying to drive the beam left/right up/down and it seems that it would need around 600vac. There must be some incredible mosfet that could handle that many volts being driven by a tiny voltage from arduino driven circuit. For instance if I made a DAC that put out -2v to +2v (or whatever low voltage) into a opto isolator (not to freak me out about blowing my circuit up) into some mosfet that won't explode over 600v.

Pete


Wish he had the tube mounted should experiment with them housed in a case .

If you look at the deflection circuits in the schematics in VCR139 the deflection transistors are rated 300 400 volts have to double check memory fading a bit but they are high voltage transistors look like normal small signal transistors but can handle voltages like that .
600 volts seems a bit high both mine crts worked on the same circuit voltages ...
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Re: XY Monitor / Display

Postby FlyMario » Sun Aug 26, 2018 3:34 am

I am sure that 600v is probably some real maximum. I bet you that it really only needs 300v Peak to Peak.

Voltage doublers. I can't even imagine. I must look that up. I know it is possible and it probably negates a ton of amps but I think at high voltages it is very low ma.

I would almost bet the heater probably uses more amps than anything. But that is probably my lack in experience.

So that I understand, are you saying you would take the 12v Peak to peak from the transformers and double it to get to the high voltages or am I just misunderstanding?

So what scares me is people take these neon transformers right... and 2kv and the voltages fires across a gap. I just don't want to see voltage leaving the wires. I know the insulation must be protecting tv circuits. I see people working on breadboards... I would expect to see plasma crossing between wires.

I can picture me creating voltage multipliers and having some crazy effects. I know this is silly. I am sure that will keep me safe though... being respectful of its power.

https://www.amazon.com/gp/product/B01C2 ... UTF8&psc=1

I purchased a couple of the 40kv (no I don't believe it is really 40kv) transformer modules that I apply 3v from my bench power supply (it shows around 3amps) and can get a spark that will scare the f out of you. I mean it is loud and bright. It was to scare the kids on Halloween. I can surely print a box around it to keep the trick or treaters safe. I only mention this because I see that thing and I imagine what my circuit might do.
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Re: XY Monitor / Display

Postby FlyMario » Sun Aug 26, 2018 4:00 am

https://youtu.be/olABTLCsXtU

Well, that looks like a pretty fun circuit. Didn't realize that they were this "simple". But yeah I could see how you could take an AC transformer and get the voltages you needed.


Need to see if I pulse a square wave through if it would work the same way. I imagine it would.
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Re: XY Monitor / Display

Postby Harry Dalek » Sun Aug 26, 2018 9:35 am

FlyMario wrote:I am sure that 600v is probably some real maximum. I bet you that it really only needs 300v Peak to Peak.


i Have to review this part of the project again but thing back 270 250 v seems it

Voltage doublers. I can't even imagine. I must look that up. I know it is possible and it probably negates a ton of amps but I think at high voltages it is very low ma.


The Voltage multiplier is pretty simple to get the voltages just have to tack on another cap and diode rated of cause correctly ...so any AC out of what ever you have could be used just you need more or less diode caps depending on whats coming out of your Transformer ...so 200 volts you can work with that .

I would almost bet the heater probably uses more amps than anything. But that is probably my lack in experience.


Well its a little light globe really not all that bad i have used Tiny 6.3 volt transformers for it

So that I understand, are you saying you would take the 12v Peak to peak from the transformers and double it to get to the high voltages or am I just misunderstanding?


as below peter
123.jpg
123.jpg (99.1 KiB) Viewed 3630 times


So what scares me is people take these neon transformers right... and 2kv and the voltages fires across a gap. I just don't want to see voltage leaving the wires. I know the insulation must be protecting tv circuits. I see people working on breadboards... I would expect to see plasma crossing between wires.


Very very deadly they could of done the same thing with just those tiny little lap top back display inverters they go to 1 to 2 kv ...when you make a supply and you know how it works you tend to be safer with it .

I can picture me creating voltage multipliers and having some crazy effects. I know this is silly. I am sure that will keep me safe though... being respectful of its power.


Yes safety first ...

https://www.amazon.com/gp/product/B01C2IVE6Q/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1

I purchased a couple of the 40kv (no I don't believe it is really 40kv) transformer modules that I apply 3v from my bench power supply (it shows around 3amps) and can get a spark that will scare the f out of you. I mean it is loud and bright. It was to scare the kids on Halloween. I can surely print a box around it to keep the trick or treaters safe. I only mention this because I see that thing and I imagine what my circuit might do.
[/quote]

No they are not they are adding on zeros ! more 4kv the red wire could be positive negative but the type i got for my crts were 3v to 6 or 7 kv and and did have diode cap in side so dc ..the other i got was just ac out have not used those...the red wires to test you need a HV probe to you meter or you will kill it .
mine was for bug zappers but now in a sstv feeding the anode of a P7 CRT and the other a NBTV crt both magneticly deflected ...cuts out the big fly back transformer ...
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Re: XY Monitor / Display

Postby Harry Dalek » Sun Aug 26, 2018 10:15 am

]
FlyMario wrote:https://youtu.be/olABTLCsXtU

Well, that looks like a pretty fun circuit. Didn't realize that they were this "simple". But yeah I could see how you could take an AC transformer and get the voltages you needed.

Need to see if I pulse a square wave through if it would work the same way. I imagine it would.[/quote]

Once you know they are easier to construct below is the one i used on the cyclops vidicon camera getting positive and negative from the same Ac rail
cyclops.jpg
cyclops.jpg (38.2 KiB) Viewed 3629 times

..i also got the heater supply from the center tap
cyclopsIMG_1724-crop.JPG
cyclopsIMG_1724-crop.JPG (35.76 KiB) Viewed 3629 times
]

a few little transformers can do the job of a big one .. back to back 12 volt transformers are the way to go for the HVspupply other wise it costs a bit ..they are cheap and why not ?
You have to use diodes rated for the volt in4007's are 1kv nice and safe and i use 10 uf's 450 v for the multiplier
heres a smaller version of steves circuit i used on the second monitor
devil.JPG
devil.JPG (418.4 KiB) Viewed 3629 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.
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Re: XY Monitor / Display

Postby FlyMario » Sun Aug 26, 2018 10:29 am

I wish this forum had a thanks button or thumbs up.

Thanks a lot, Harry for your info! This seems fun and I look forward to working with this info.

I probably should start a new thread. It stopped being about the topic weeks ago! :wink:

Pete
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Re: XY Monitor / Display

Postby Steve Anderson » Sun Aug 26, 2018 2:07 pm

FlyMario wrote:I probably should start a new thread. It stopped being about the topic weeks ago! :wink: Pete


Well, maybe not, it is still an XY display as all TVs are in some form or another. But if you want to start a new thread with a more suitable title, please go ahead.

Voltages on transformers are invariably AC (RMS) voltages, as is the 110/220V mains supply. RMS = Root Mean Square, Wikipeadia have quite a good explanation of what that means without it being too heavy on the maths.

Basically a light bulb (a glorified resistor) will be the same brightness on 110V RMS AC as on 110V DC. Same with a heater element in an oven (another glorified resistor) will get to the same temperature. Again the same with the heater for a CRT, also specified in volts RMS.

RMS generally comes with the unspoken assumption that we're dealing with sine waves. You can measure other waveforms as an RMS voltage, but there's not that many uses for that.

Harry saying he contemplates his next project for months ahead is sage advice. Dig up all the information you can on whatever you plan to use, start sketching ideas, doing research on-line. Look up other peoples designs. Don't copy them, you can if you wish, but use them as a source of ideas.

You rarely find toroidal transformers in consumer stuff as they are more expensive than an equivalent standard laminated one. You'll see them more in industrial equipment and where weight is important (aircraft) as they are lighter. There are companies (Airlink in the UK for example) who will make you a custom toroidal transformer with whatever windings you could desire on it, in sizes from 15W up to a few kW - and the good news is they're only a few percent more than their standard range - even for just a one-off. Sometimes no increase in price if it's simple.

I have no connection with Airlink except as a satisfied customer.

Steve A.
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Re: XY Monitor / Display

Postby FlyMario » Sun Aug 26, 2018 11:57 pm

So, I ordered a 6.3v transformer. I am satisfied with that.

https://www.amazon.com/gp/product/B005T ... UTF8&psc=1

Feel more guaranteed I am not going to hurt the heating element with that.

I purchased two of these.
https://www.amazon.com/gp/product/B01NB ... UTF8&psc=1

Harry,
I am confused about putting two transformers together. Are you trying to make a center tap out of two of the legs? As in one pole connected to the other pole?

pete
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Re: XY Monitor / Display

Postby Steve Anderson » Mon Aug 27, 2018 3:06 pm

Well, the first link/transformer has a current rating of 6A, I'm assuming the only load it's going to see is the CRT heater. If that is the case you may want to measure the output voltage before you connect it up to the CRT - it could be around 7V. To get around that you'll need to know the heater current and work out what low-value series resistor you'll need to put in series to get 6.3V at the CRT. 7V (say) is 11% high, resulting in around a 20% increase in power and a shorter life on the tube.

They will tolerate a reasonable variation but 11% is too high for my liking. But the series resistor will fix that.

So when you receive this transformer power it up with no load and measure the secondary voltage. Given the CRT heater current (and voltage) it's a simple ohms law calculation to work out what value of resistor and its power rating you'll be needing.

The second link/transformer...I'm not sure what you are planning to do with these two....if you're planning to use them back-to-back to get the high voltages for the CRT your problem is they only have 110/120V primaries from what I can see. Ideally you want 110 to 12V, then feed that 'backwards' into a 12 to 220V transformer.

Steve A.

My mistake...the photo shows a 6A version for the 6.3V transformer but reading more it's 1.2A which is ideal.

Actually the link you provided to the 600V/6.3V/5V transformer seems ideal doing away with the back-to-back arrangement. I wish we could still get things like that here. PDF attached. So what are your plans for the two 12V/2A transformers?
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Re: XY Monitor / Display

Postby Harry Dalek » Mon Aug 27, 2018 7:21 pm

="FlyMario"]Harry,
I am confused about putting two transformers together. Are you trying to make a center tap out of two of the legs? As in one pole connected to the other pole?pete


As Steve mentioned that Transformer seems fine for the job ...i do these things on the cheap and was mentioning the back to back transformer idea to save money ..and it seems you have no problems getting a transformer that does the job ..apart from needing 12 volts for the circuits with that is a good start .
You might not need a second transformer for the 12 volts voltage doubling on the 6.3v a regulator perhaps might do the trick.
Good idea once you get is mount it in a case ..i just AC outputted the supply to the monitor via a multi core cable

The back to back transformer idea ...mains supply is to primary then out secondary to the another same transformer secondary and out its primary will be 200 volts or so if you use 2 12 volt output transformers .... just a step down the voltage then step it back up again.
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.
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