HOW TO FIX THE NONSTANDARD APPLE-1 VIDEO

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HOW TO FIX THE NONSTANDARD APPLE-1 VIDEO

After having fixed the nastier quirks of the Apple-1, which did cause it to crash all too often, your "Uncle Bernie" proceeded to fix some of the less pressing issues, such as the video signal, which in the original design is wrong, as it does not conform to the NTSC standard, and makes finding a monitor that works with the Apple-1 more difficult than we want it to be.

 

As with the other quirks of the Apple-1, this video signal issue did not deter the two Steves from selling their cute novelty, because it almost worked, or it worked most of the time, and so none of the many quirks it had - like dogs have flea - was a "show stopper".

 

We can't demand any perfection from any novelty product, and the Apple-1 indeed was the world's first microprocessor and DRAM based single-board computer complete with character video output and keyboard entry, and a BASIC interpreter. Nobody else had that in 1975 !

 

To be more precise about the timeline, in late 1975 the handwired Apple-1 prototype was shown, only a few months after the 6502 became available in mid 1975 (with the ROR bug), but since then, the race was on ! The two Steves had no time to lose and when the PCB based Apple-1 was for sale in mid 1976, they still were a bit ahead of the competition. The history is full of examples where inventors / innovators were still perfecting their product, losing time, while the competition already got rich with inferior, less perfect products of the same kind. This perfectionism for novelties is a trap that needs to be avoided. So the two Steves did the right thing. The industry calls this "good enough": if the customers buy a product and don't get furious enough to make death threats, or to become members of a class action lawsuit, then the product is "good enough" to be sold. Another example for this mindset: American made cars. Juuuust "good enough". If you want more perfection, buy a Japanese or German made car, but keep in mind that inferior parts "Made in China" began to appear in their supply chains, too. 

 

As to the Apple-1's video signal being "good enough", most of the primitive B&W monitors or modified TV sets from back in the day could take the abusive, non-standard video signal produced by the Apple-1 without acting up too much. On my old Shibaden Model VM-903U monitor, probably made in the late 1960s, the only ill effect caused by the non-standard video signal was a character field sitting too far to the right, so the last column of characters was outside the visible area, until I adjusted the magnet rings on the CRT to move the scan field off center. This operation on a monitor under power certainly is not exactly "consumer friendly", but back in the day, almost anyone who ventured into these first microcomputers was an electronics engineer or such, and could do this (or other) mods. Some daring individuals not afraid of death even wired a video input into their hot-chassis type TV ! (Don't do this, it may turn your Apple-1 into an electrocution machine that can kill anyone who touches it). These were the wild times when even 12 year old kids could play with matches and gunpowder without being arrested as "terrorists". Today's "laws and regulations" would have killed the fledgling hobbyist computer "industry" on the spot. Remember how the FCC nearly succeeded with that in the late 1970s, once they woke up and passed ridicolous regulations which forced Apple to redesign the Apple-II, and forced Atari to put several pounds of die-cast EMI radiation shields into their Atari 400 and 800, greatly increasing costs ? A few years after that the FCC had to roll back their excessive regulations because they were crippling the whole computer industry. Then, all of a sudden, cardboard shields with thin aluminum foil were "good enough" ! Government at its best ! But back to the Apple-1:

 

The root cause for the character field not being centered is that the Apple-1's HSYNC pulse is 10us wide, and not 4.7us as specified for NTSC (and PAL), and the unwanted additonal 5.3us come too early after the character field. If you study the Apple-1 video circuitry long enough you will find out why Woz made this compromise: the wicked way the horizontal counters work does not offer any low gate count way to make a HSYNC conforming to the NTSC standard by digital means. Doing it right might have cost at least one more TTL package. Typical analog, CRT based TVs or monitors of the time could digest the non-standard Apple-1 video without throwing up, except for a misplaced character field in some cases.

But this more modern little B&W TV I bought off Ebay, used, for cheap, could not take the Apple-1 video signal without refusing to work properly:

 

 

It's a "Personal Black & White TV with AM/FM radio", Made in China (what else did you expect for the $39.99 price tag it once had ?), from an unknown manufacturer who, despite being Chinese, was too ashamed to put his name anywhere on their not-so-fine "product". Maybe they wanted to avoid death threats from desperate customers, who knows. (You might notice I have a lot of dark humor ... this inevitably comes with age, when you witnessed 50+ years of mankind's devolution and dumbing down).

 

As a cheap disposable TV and Radio, it may be "good enough", although my expert eye trained by many years of designing ICs for TVs (until the very last CRT based generation) shows me that it's guts are crap, and not due to age, but by design. Buyer beware, you may get what you pay for, and never expect to get more value than you pay. These little TVs are just too cheaply made and for a little more money you could get a much better one. But in this case, its refusal to display the Apple-1 video is justified, and not due to it being too cheap. Many more modern TVs and monitors, regardless of price class, would show similar symptoms.

 

The reason for the distortion on the first few scan lines is that the Apple-1 does not produce a serrated VSYNC as required by the standard, which would have cost one XOR gate with two inputs. Without a serrated VSYNC, the horizontal oscillator (or its digital equivalent) may lose synchronisation during the vertical sync period, and then it may not be able to regain synchronisation fast enough to be able to show a good picture. On some TVs / monitors, you may get a mostly stable picture, but with some ugly distortions of the beginnings of the first few live video lines, which shows the lock-in process for the horizontal oscillator. On other TVs / monitors, the horizontal oscillator never acquires lock, due to the non-standard video signal, and the whole picture falls apart (or "crawls" around).

 

Now, the Apple-1 has no XOR gate anywhere in its circuitry (except within the 6502, and those we can't use to fix the video). Also, like with all of my mods to fix the Apple-1, I did not want to add ICs nor cut any PCB traces on the motherboard. These requirements come from my desire that my mods also should be acceptable for Apple-1 originals, and removable by just de-soldering the added components, without leaving any trace.

 

Within these requirements, alas, even I can't find a perfect fix for the video problem. But I have developed a mod which both adds the serrations in the VSYNC and shortens the HSYNC to conform better to the standard and centers the character field on the screen.

 

Here is the schematic of the video fix mod:

 

The five parts for this mod cost 10 cents, and if you paid 25 cents (US "quarter") for them, you got ripped off. All you need is a PNP transistor, a 47pF capacitor, and three resistors, of the values 3.3K, 5.1K, and 100K. Any small-signal PNP with a hfe better than 125 will do (and this means, almost anyone, TUP = Transistor, Universal, PNP). The tolerances on the timing components (47pF and 5.1K) should be tight (1-2%). The 1% tolerance on the 3.3K resistor is to avoid adding yet another widely moving target to a node where other components (the R1, R2) already have introduced large tolerances. The tight 1% spec can't cure these, but it will reduce the probability of the mod not meeting target criteria. If you seek perfection, you could replace this 3.3K resistor with a 5K trim pot and adjust it until an oscilloscope shows the same voltage level just before the (shortened) HSYNC as the black level voltage in the live video portion. Then put in a fixed resistor of a close enough value. But I don't think such a manual adjustment is necessary, as typical TVs and monitors are quite tolerant to what happens just before the HSYNC, and if there is a little step there to either side of the black level, nothing bad will happen. If the step is upwards, there may be a faint grey bar outside of the visible portion of the screen, and if the step is downwards ("blacker-than-black"), you can't see that anyways.

 

This is how the mod looks installed in one of my Apple-1 built on the "Replica-1" PCBs sold on Ebay by "Pinguso". Other PCBs not based on the open-source Gerbers may look slightly different, but the general location of the solder pads and traces should be the same:

 

 

The yellow cylindrical capacitors belong to the reliability mods, and not to the video mod.

 

Here is a closeup of how the five added components are soldered in place:

 

 

Here is a screenshot from the same little TV as above, after the video mod was put into the Apple-1:

 

 

 

The picture is now stable, and the character field is centered in a better way.

 

All this was achieved by adding just one transistor and four passive components costing maybe 2 pennies each. Woz could have designed in those 10 cents worth of components to have a less troublesome video signal closer to the standard. Instead, they recommended a certain type and brand of TV / monitor which worked better with the non-standard signal than others, or so the story often is told. Sigh ! ~45 years too late, I have added my proverbial "10 cents worth of advice" !   

 

Those who are younger and have better eyes than me may want to try to implement this mod using SMD components. These "bird feed" parts are so small nowadays that the mod would be barely noticable. But in any case, make sure not to allow any leads to touch PCB traces, despite the traces have solder mask. Solder mask is thin and no reliable insulator. You don't want to produce a hard-to-spot short below a component.

 

Here is an oscilloscope screenshot showing the now serrated VSYNC:

 

 

The red circle is at the end of the VSYNC and the "needles" seen there are the serrations added by the mod, which are short positive pulses at the HSYNC rate, and these keep the horizontal oscillator in the TV or monitor synchronized. The original Apple-1 VSYNC lacks these serrations, which makes many TVs or monitors unhappy.

 

And here is the now somewhat shortened HSYNC:

 

... which now is ~6us wide, still wider than the standard, but I found this may be the best compromise of HSYNC width and the position of the character field on the screen (if you want to experiment with that, just vary the value of the 5.1K resistor).

 

Note that the original Apple-1 HSYNC started at the time of the narrow glitch pointed to by the red arrow. This glitch is produced by the added circuitry, because the PNP starts to inject current into the video summing node before the combined sync signal has traveled though a D-Flipflop within the 74175 at location C13, which is clocked at 14.31818 MHz, so the glitch is quite narrow, and hence, would produce a thin, vertical, grey line on the far right side of the TV screen if this place would not be located in the "overscan" region of a typical TV or monitor, where it is invisible on the screen. If you can see it, your TV / monitor is out of adjustment. There is no way to avoid this glitch within the limitations of this super simple five components analog circuit. "Good enough" as discussed above. Don't make death threats against me and don't start a class action law suit ;-)

 

I really like this little circuit, as it proves (again) that analog designers can do a lot of things with just one transistor for which digital designers need many gates and many dozens of transistors. Remember the three transistor walkie talkie of the 1960s ? Compare that to the gazillion of transistors in your cellphone. I think it's called "technical progress". It took us half a century to get there.

 

Comments invited !  - - -

Reply to this post and tell us your results on which type / brand of monitor before and after putting in this fix !

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Well done UncleBernie!

Well done UncleBernie! ... And thanks for sharing.

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Serrated vertical pulse

Bernie thanks sharing the details of your clever serrated vertical sync fix.

It is nice to see people that understand analog video are still out there :)

I am lucky I did never encounter this problem when I use  an Apple II monitor.

When I built my first Apple I about six years, I noticed Woz took some liberaties with the video standards.

1) The horizontal sync rate matches the  NTSC color standard rate of 15734.262 hz.

2) The vertical sync rate is slightly off at 60.05 hz.  NTSC color standard vertical sync is 59.94 hz and NTSC BW standard vertical sync is exactly 60 hz.This probably explains why early Apple monochrome monitors (i.e. Apple II) had external controls for vertical hold, but not for horizontal hold.

3) NTSC is interlaced video, while the output of the Apple I is not. 

4) Vertical pedestal was not serrated with horizontal pulses as you mentioned.

 

 

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Tv that takes non standard video.
I found a 1992 Burle TC1910A B/W security monitor which does not need serrated VSYNCs and works fine with no HSYNC lock-in problem in the first few TV lines. As long as the HSYNC and VSYNC are properly adjusted you'll get a stable clear picture. 
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Some monitors/TVs are better than others !

In post #4,  AuraKSphere wrote:

 

"I found a 1992 Burle TC1910A B/W security monitor which does not need serrated VSYNCs "

 

Nice find ! Next time I'm buying a monitor  I'll look for those.  Its "looks" are almost period correct. Only few people could tell it probably was designed or redesigned in the early 1980s. 

 

For those interested in monitors for Apple-1, here is some more information for you:

 

WHY SOME MONITORS/TVs are BETTER THAN OTHERS (when it comes to Apple-1 video signals)

 

The whole issue with the sensitivity of the TV or monitor to missing HSYNC pulses during VSYNC boils down to two implementation details:

 

a) accuracy and stability of the horizontal oscillator frequency

b) design of the PLL phase comparator and the loop filter

 

Because TVs are consumer products they are price sensitive and so the cheapest and most inferior electronic components are being used. CCTV monitors for security systems are no consumer product, but professional electronics, and so much better electronic components can and will be used, and a higher price is being asked. The circuit boards of the higher quality CCTV monitors are epoxy (typically, FR4 material) which will not develop hairline cracks due to ageing like what happens with the cheap phenolic PCBs in the consumer junk or the lowest priced CCTV monitors.

 

BUY A PROFESSIONAL GRADE CCTV MONITOR AS LONG AS YOU CAN GET THEM !

 

So investing in a well preserved vintage, premium CCTV monitor is wise, if you don't have one yet for your Apple-1. They are a dying species and sadly, many ended up in landfills and still get thrown away. You can find them on Ebay only because back in the day, some people "rescued" them from the junk bin when they were decommisioned,  knowing the (shocking) price tag these high quality monitors once had. Fast forward 25 years, to "now", and its likely their heirs who want to get rid of these items.

 

BUYER BEWARE !

 

There are some pitfalls you have to watch out for, though: improperly stored ones having humidity / corrosion damage, and those which had no moving cameras and hence may have a fixed image permanently burned into the phosphor of the screen. This is faintly visible if you turn up the brightness and contrast such that the whole screen is lit, but except for the most severe cases it does not affect the display of white pixel characters on a black background in any significant way.  It would be very annoying if you use one of those to watch a movie, though.

 

Never buy any TV/monitor on Ebay (or elsewhere) where they can't show a fully lit screen - if the seller didn't snap such a photo, tell them to turn it on and adjust brightness / contrast to get a white screen, and to adjust V-HOLD to stop the picture from rolling. The whole screen must be evenly lit and stable (not rolling). Most issues with the picture tube, the high voltage generation and the deflection coils / circuits can be reveiled by this simple test. All other possible defects not covered by this test can be repaired in most cases.

 

REPAIR IS POSSIBLE (IN MOST CASES)

 

Other than that, these professional grade monitors can be rebuilt indefinitely. Only if the picture tube dies (a very rare event) or the flyback transformer burns out / dies they can't be repaired anymore. But keep in mind you do need a service manual / schematic to repair it, so look out for this info on the internet before making a decision to buy. Without a schematic, they still can be repaired, but then you have to spend many hours to reverse engineer the PCB and draw a schematic before you can start looking for the faulty part(s). Some expertise in TV circuits sure helps.

 

THE "SWEET LITTLE MONITOR" PROJECT

 

Another option would be to build new CRT based B&W monitors from scratch. I've slaughtered the little Chinese made TV seen earlier in this thread and I'm currently developing new high quality electronics for it, based on the popular (and still abundant) TEA2037A IC from ST Microelectronics. This IC was very popular and was the heart of many, many  B&W and color monitors of the "picture tube" era. Using high quality components, all the problems with the nonstandard Apple-1 video signal are gone, without using the video fix. In the final version there will even be a trim pot to center the position of the character field. But I'm not yet there. More lab work is required. It already stably generates the 12,000 Volts for the picture tube and scans the electron beam correctly, and I can get a test picture. Still, more fine tuning and refinement work is needed. The application notes from ST are quite OK but they don't tell everything. Here is how it looked on my lab bench a few days ago:

 

 

When all the development work is done and it performs satisfactory, I will design a PCB for it and make it available for cheap (< $10 ?). All you need from that little Chinese made TV being used as a parts donor is the picture tube and the flyback transformer (the black tower with the red cable at the right side of the circuit board). All the other low quality and worthless components are tossed into the trash, where they belong. These TVs are abundant on Ebay and cheap, typically $40 including shipping, and the best thing is, they were rarely used, so the picture tube should still have many thousands of operating hours left. But in their original configuration, they won't work with an Apple-1 not having the video fix.

 

Anyone interested in a DIY home-built little monitor for his/her Apple-1, please contact me by a personal message here on Applefritter. Like with all of my work for the Apple-1, I do need some cheer ups and some interest from the Apple-1 crowd to be motivated to pull development fully through. Otherwise I'm very much inclined to stop after all the hard nuts have been cracked and I have proven it works, but to turn such a thing into a sort of "product" others could use requires much more time, and unless my work finds such use, I don't want to invest all that priceless RQLT into drudge work that is not intellectually stimulating for me. There is a reason why the industry has different teams in the product development process: those highly skilled experts who find the solutions to the tough problems,  and then those who turn these solutions into the product: finishing all the mandatory tests, designing the PCB, designing the enclosure, writing the manuals, preparing production ... lots of work, much more time needed than the expert had to put in to find the solutions in the first place.

 

You might wonder why I want this little homegrown monitor so badly ... think about an Apple-1 notebook computer in an attache case of only 5" height, and when you open the lid, the monitor pops up and the Apple-1 is in the lid. Take the keyboard out and start computing ! This is only possible with these tiny 5.5" picture tubes. Smaller ones are illegible for me. LCD displays are a no go, of course ! (We want to stay period correct).

 

Comments invited !

 

- Uncle Bernie

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Good idea

To me personally, the idea of a fully portable Apple 1 had been floating around my mind since I started my journey into building these boards and saw that picture on wikipedia of an original with all the goods, minus the tv, in a breifcase.

 

Given this whole mini TV build would probably be about a total of $50 based on uncle bernies numbers, it seems overall it would be a good thing as most security monitors like my Burle can set you back $80 to well over $200 depending on quality, manufacturer and year made and usually not including shipping which can be high as well. I got lucky and found mine for about $75 (shipping included which was half the price) and got even luckier since I bought it without seeing the aforementioned bright screen test. 

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Tentative cost estimate for the "Sweet Little Monitor"

In post #6, AuraKSphere wrote:

 

"Given this whole mini TV build would probably be about a total of $50 based on uncle bernies numbers"

 

Uncle Bernie answers:

 

It will be a little bit more expensive, because other than the "parts donor" Mini TV (an "Electro Brand" Model 327K which currently is abundant on Ebay: I bought 7 of them within 2 weeks and as of today, 6 are listed) and the PCB you also have to buy some other electronic parts, such as the TEA2037A IC, some resistors, capacitors, and trim pots. These parts may cost a few pennies or dimes each (even if high quality) but this can quickly add up to $10-$20. Then you need a mounting frame / bezel for the picture tube. You could cut the plastic part out of the slaughtered TV enclosure, but I didn't try this yet as it's still needed in the "lab rat". This plastic part comes with the TV (~$40). Add PCB (~$10) and ~$20 for the other electronic components that need be bought new. Only an idiot would salvage the low quality junk capacitors and trim pots out of that little TV,  don't ask how I know that. Well, just joking. I'm not that idiotic. I knew they are Chinese junk and very likely would cause trouble, but I had to use a few salvaged parts from the TV as I could not find the right values in my parts stock. As a consequence for such wrongdoing,  I had to spend hours to hunt down the culprit causing parasitic oscillations in the vertical deflection coil driver stage.  Of course it was the junk capacitor salvaged from that mini TV ... ouch ! Penny wise and hours foolish.  It had worked in their crappy little TV. I still ponder over the Chinese schematics how they could use such a lousy capacitor in their own vertical driver stage. There are some resistors and small capacitors arranged in a local feedback network around their driver stage which bypass the junk capacitor. This network appeared to be superflous to me when I reverse engineered these schematics. In hindsight, the clever Chinese designers added this extra network for maybe 5 pennies to save the maybe 20 pennies a high perfomance Japanese electrolytic capacitor in the coil branch would have cost more compared to the lousy and cheap Chinese one. The dark mysteries of Oriental electronics ... I never understood how they could make such a TV and ship it half around the world to be sold at retail for $39.99 (one came with the original bill of sale in the box). The TEA2037A application circuit from ST Microelectronics obviously must have used such a high performance electrolytic coupling capacitor, but they did not mention this fact. Uncle Bernie's fix to the problem was even more clever than the Chinese 5 cent network: I added a single 1 cent ceramic capacitor in parallel to the lousy capacitor, so it got much better performance at higher frequencies. And the oscillations were gone. This is how Western electronics engineering beats Oriental electronics engineering: you need to know what you are doing.  But back to the expected costs.

 

Expect about $70 in total for the electronics.

Then add the costs for the mechanical mounting components. 

 

CNC milling of a nice wooden mounting frame would be the most luxurious solution. But try to find a wood working shop with a three axis CNC mill ... and the costs for the programming of the machine would be staggering (the curvature of the picture tube makes it difficult).  There are some other solutions which come in mind and are probably cheaper and still good looking. 

 

For a truly portable Apple-1 in a briefcase / attache case this is the only solution I see. I had bought a little professional CCTV monitor a while ago but despite the screen is too small for me to read the characters, it would not fit into a 5" briefcase because they placed the adjustment knobs below the screen (which adds 1" to the overall height) and they designed the sheet metal enclosure around this form factor. Even the PCBs are too large.

 

But anyways, I'm glad that my "Sweet Little Monitor" project has already found one follower ! (so qty 3 of the to-be-made PCB already "sold" !) 

With enough interest, I might even make a few kits with all the parts (for economies of scale).

 

Comments invited !

 

Uncle Bernie

 

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Hi Uncle Bernie!

A monitor is certainly a good thing. And how are things going with the 5.25 drive card project for the Apple-1, which you so intrigued everyone with this spring?

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In post #8, macintosh_nik

In post #8, macintosh_nik wrote:

 

"...how are things going with the 5.25 drive card project for the Apple-1, which you so intrigued everyone with this spring?

 

Uncle Bernie answers:

 

this is off topic for this video thread. I've answered in the Apple-1 floppy disk thread (post #22) which is:

 

https://www.applefritter.com/content/uncle-bernies-woz-machine-based-apple-1-floppy-disk-controller

 

The point is, I am able to design anything electronic you would ever wish. Before retirement, I was one of the top 10 IC designers of the absolute top notch semiconductor company of the world, Linear Technology (LTC). A shitty company not to be named under the helm of the most vile CEO  in the whole worldwide semiconductor industry bought LTC and this terminated my career.

Before that I had a heroic fight (think Brahma-Vishnu-Shiva fight) against the psychopathic/narcicisstic/machiavellian ("dark triad" personality disorder) director of the Colorado Springs design center of LTC but I was protected by my much cherished mentor, Bob Dobkin, CTO and one of the founders of LTC. When the shitty company bought LTC, Bob Dobkin was degraded to what we call a "breakfast  vice president" and he could not protect me anymore against that scumbag director. I had to go. The scumbag director tought that my last project could be finished by others, but that was a fallacy -  they don't have anyone in my league left. The only satisfaction is that the scumbag got the "vaccine" so he will die in the next few years anyways. No need for me anymore to put a bullet in his foul head. He killed himself already, by taking the "vaccine".

 

But you need to understand how I tick respective to the Apple-1 world. I sell off my superflous IC stock I bought for $27000, in the form and shape of kits.  I do my best that "my" builders succeed with their builds. I spend a lot of time to help them via email. But after my overstock is sold (kit #100), that's it. I will pursue other target objectives after that. For me, the Apple-1 is only a hobby and a pastime until the sky opens up again I can fly my private airplane again to foreign destinations (if that ever happens). When I retired, I intended to fly around the world in my own airplane and stay wherever I would like it. Think islands in the Indian Ocean (I lived for years on those islands) or the Pacific (Jack London South Sea Tales is all I know, I would love to live a while in Tahiti / Bora Bora but I never was there yet). I have no limit on most of my credit cards except those I use for online shopping (by design).  I could do whatever I want to do. But the various  fascist  governments response to this virus foiled my plans and I'm getting more and more angry about that.

 

Comments invited !

 

--- Uncle Bernie

 

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Alternative Values For Resistor and Cap

Hello there,

 

On my journey to get my Apple-1 working with a modern LCD/HDMI tv set, I stumbled upon Uncle Bernie's video fix which I built and it worked out of the box.

 

Yesterday, though, I got a SONY PVM-97 monitor (made in 2000) which has a similar look and feel as the Sanyos but it is much more affordable (200 USD instead of 1k to 2k for a Sanyo). But: It did not work with Bernie's fix. The picture was shifted and the first lines warped and distorted.

 

So I rebuild Uncle Bernie's fix on a breadboard but replaced the resistors with potis to see if I can make it work. And, tadaa, I came up with settings that work for the Sanyo's (well, I think it improves the picture even a bit), the Sony and also on my Samsung TV. The picture on the Sony is really, really nice (nicer than on my Sanyo)

 

Here are my adjustments to Bernie's Fix:

47pF -> 30 pF

5k resistor -> 20k

100 k resistor -> 75 k

3.1 k resistor -> 3.3 k

 

All resistors I used are are 1%, 1/4 Watts.

 

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Hi all,here's my contibution

Hi all,

here's my contibution to the topic.

These are the values I determined experimentally to make the modification work with all my monitors (LCD/LED/CRT):

 

Transistor: BC212B

Resistors:

5k1 --> 5k6

100k --> 100k

3k1 --> 3k3

Capacitor:

47 pF --> 220pF

This last value is quite far from expected and strongly needed only by my FHD monitor, so reluctant to work properly.

With smaller capacitors all I had from it was just a NO SIGNAL indication.

 

For everyone's convenience I would like to put all informations together in a single document and share it publicly (even on Facebook/etc).

Uncle Bernie: you would be given full credit, of course. Is it ok for you ?

 

Cheers,

Claudio

 

 

 

 

 

 

 

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In post #11, p_lab wrote: 

In post #11, "p_lab" wrote:

 

"You would be given full credit, of course. Is it ok for you ?"

 

Uncle Bernie answers:

 

Yes, of course, Claudio, go ahead ! I do this work for the benefit of the whole worldwide Apple-1 user community so the more it is known, the better !

 

But please include the link to the original thread here on Applefritter so people can look everything up how it came about, and what the symptoms are, and what the original sizing of the components is. I think the 220pF is excessively high, and I would not recommend it as the default configuration, but as we say here in the USA, "What works, works !" (Pragmatism at work. Japanese and German engineers would shudder. Another lovely American proverb is about the use of "Duct tape, baling wire, and spit" to repair things. Duct tape is absolutely wonderful ! You can even use it to close holes in aircraft wings caused by bird strike !).

 

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Please put it on something

Please put it on something other than Facebook.... Some of us refuse to use any product from them.

 

 

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About the evils of Farcebook ...

In post #13, Corey986 wrote:

 

"Please put it on something other than Facebook.... Some of us refuse to use any product from them."

 

Uncle Bernie comments:

 

I would never consider to use Facebook myself, ever, and I refuse to use a "smart phone", too. Both collect data about the user (the "smart phone" even listens to your conversations, transforms them into text, compresses the text, and sends it to the Gestapo, or whatever it's called in your country). Same thing with "Alexa" ... it always listens. And somewhere, in the Cyberspace, there is an AI bot who analyzes everything you do and everything you and your guests say. It will use the contents of your conversations to build a personality profile of you, about your friends, your acquaintances, your desires, your financials, your sex life, everything. One wrong word, and the AI will red flag you and the Gestapo meat bots will start to target you. 

 

If you ever have wondered why your smart phone has such a powerful speech-to-text function, now you know. Or do you think you paid for this speech-to-text software when you bought the device ? Think again ! The Gestapo paid for it. Using your taxpayer money, to eavesdrop on you, and you are an accomplice in that crime perpetrated against you. There used to be better times where "they" needed a warrant signed by a judge to plant a listening device in your house. Plant the listening device yourself, no such rule of law needed. Orwell never explained in "1984" whether the ubiquitous "Televisor" was bought by its victims with their own money, or if it was furnished by the State.

 

Facebook (and similar "social media websites") are just honeypots to suck you in. They were founded and financed and built by the Gestapo (or whatever it's called in your country). Or do you think a degenerate meat bot like Mr. "Sugarmountain" could have done it all by himself ? All the stories about how he started Facebook while at college, for his "friends" on the campus,  even the story he stole the idea from a room mate, are all red herrings to distract you from the truth ! Even his name may be a fabrication. The "mountain of sugar" at the fingertips of the Gestapo, of your controllers. This "sugar" is the data they harvest from you. And they know more about you than you know yourself about you. Seriously. You forget what you said a day, a week, a year ago. Or the places  you went. Or whom you met. THEY never forget. And then you wonder why you can't get another credit card, or can't buy a gun anymore, or end up on a no-fly list. Maybe the AI bot misunderstood the movie you watched in presence of your smartphone for a terrorist plot you are involved in. Boom. You are finished. And you can never get this stain off your slate. They may fix their buggy AI which did that to you, but you can't sue them for damages (try sue the government). 

 

So this are the dangers. It even gets worse when they sell your digitzed self to third parties for profit.

 

So I agree with Corey, "Some of us refuse to use any product from them"

 

Smart move.

 

But for those who already use Facebook, and are already hopelessly ensnared in that spider web, it doesn't matter if Claudio posts Apple-1 stuff there. As far as I'm concerned, I don't think the Gestapo will construe my video fix circuit to be a terrorist act. (Hopefully so).

 

So go ahead, Claudio.

 

But I will never see what you post on facebook.

 

- Uncle Bernie

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Thank you guys!

Thank you very much Uncle Bernie for developing this circuit and sharing it to the community and thanks to Claudio for putting this in a handy document. Much appreciated :-)

 

best regard

Denis

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