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What is this witchcraft? Heresy! 2600 switching power supply modification


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#51 -^CrožBow^- ONLINE  

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Posted Mon Mar 20, 2017 5:24 PM

Got them in today's mail...HOLY CRAP they are Tiny?! They are actually smaller than a standard 7805 in that they are only maybe 3/4 the height and just a hair wider and only a hair thicker as well. So yeah, these should fit incredibly well in all applications. These have to be even smaller than the other DC-DC buck converters that were listed from Oki..etc. I will put two of them into my Genesis tonight and post results.

 

Also received my Kill-a-Watt reader in the mail today too, so hopefully I can get some initial readings on energy use. Not sure if the wall warts will alter or keep the same readings since it will be the one drawing the power. Also my Genesis doesn't normally use a sega adapter. I actually have one Golden.Ax's converted GC power supplies driving my Genesis/Sega CD/32x combo. I believe those are switching type power supplies already so yeah... 

 

But that power system is all buried literally behind my console display so I'm not taking everything out to measure it. I will only be able to measure just the Genesis from a stock sega brick.


Edited by -^CrožBow^-, Mon Mar 20, 2017 5:26 PM.


#52 Osgeld ONLINE  

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Posted Mon Mar 20, 2017 6:22 PM

I dont think a kill-a-watt is going to show a whole bunch, the stock 7805 doesnt consume any meaningful amount of power, its all in the wall wart and the system consumption, what will be interesting to see if what interference you can see on screen 

 

smps's by their vary nature radiate radio noise, so while it may have a nice filter system to keep noise low on the output power, it is still a very low powered ultra tiny radio transmitter ... whether it effects anything or not depends on its internal switching frequency/ harmonics and internal shielding  ..ie if its switching at I dunno 500khz and its got a 2db harmonic spike in the low mhz range it might show up as effects on a composite video signal, or higher frequencies in the RF signal that dont really effect the base signal or whatever combination of both 

 

of couse the downside to linear regulator is, as we all know heat.. now with some very simple filtering you can make those little buggers output just about totally flat output and you can easily get darn near an amp out of them, even in the 80+ % range

 

course game consoles and toys dont do any of that, heck most of them wont spent a single penny to put a diode in place for simple reverse protection, so its not really the regulator's fault ... its just low cost design, and lets be real here, there's a metric ton of them that have been running since the 70's with no problem 


Edited by Osgeld, Mon Mar 20, 2017 6:26 PM.


#53 -^CrožBow^- ONLINE  

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Posted Tue Mar 21, 2017 9:17 AM

Okay...so I installed two of the Traco buck converters into my genesis last night. However, I ended up taking them back out...here is why:

 

So first the good -

 

Standard stock supply was showing a constant 20va rating while in use overall draw according to the Kill-A-Watt.

The Power Factor indication was showing a steady .67. My understanding is that you want this closer to 1.0 I believe?

It was showing a usage of 16.8 watts while powered on and running Lightening Force in demo/attract mode.

Actual volts from the adapter was showing it was pulling in a steady 13.9 from the AC directly.

 

With the Traco converters installed I got these readings -

 

16.5 constant overall VA draw

Power Factor was worse showing .51 constant reading. Again I've read you ideally want this closer to 1.0.

It was only using 6.8watts of power...yeap... much less watts being consumed to operate.

Actual voltage being pulled from the AC to the stock adapter was only 8.9. 

 

So with the exception of the Power Factor rating, it would appear that running a set of these in a genesis with a stock power supply will still be quite the improvement in overall power usage and efficiency.

 

Now for the bad...

 

So... the main issue and it was enough to make me put both of the 7805s back in was much louder and whining noise on the audio. Lightening Force (Thunder Force IV) was more obvious and I really couldn't handle it. Additionally, I would also hear a weird rhythmic ticking in the audio line during quiet or silence in the game. And it wasn't a subtle ticking either...very audible and easily picked up. This doesn't happen with the 7805s installed.

 

The other issue and I'm not sure if it related to the Traco converters or not, is that while TF4 played well enough, I was having more issues than I usually do with Sonic 3 just resetting itself randomly within a few minutes of starting a game. This was made worst with Sonic and Knuckles also rebooting itself constantly within about 60sec of starting a game. If you just left Sonic and Knuckles on long enough, it would eventually start to reboot just after the sega logo or right after displaying the title screen logo. With the 7805s in place, this doesn't happen.

 

That said...I have noticed that I can't get Sonic3 and Sonic And Knuckles attached to work on my Genesis at all. It will go through frequently reboots as well, and show corrupted graphics...etc. but only with them docked. Played separately they are fine. This is my test bed genesis and has seen a lot of mods done to it over the years...so it could just..be...tired. It has been recapped as of about 2 years ago so that shouldn't be an issue. But it does appear that the Traco converters on a Genesis at least do work for the most part, but present some very audible noise and ticking in the audio and might have issues with some of the more complex games. One game I didn't try out now that I think about it, is Virtua Racing and I likely should have. I also didn't test with the 32x attached.

 

Honestly with the increased whine in the line level audio and ticks...I just didn't see a point to continue on.

 

However, I can tell you that the s-video picture quality was completely unaffected by the Traco converters and they do run much much cooler. You can touch them easily and they only get warm. But I did notice the one closed to the power connection gets more warm to low level hot as compared to the one closer to the YM2612 location.

 

So...those are the results. Less power required and consumed so it does appear to be much more efficient even with a stock power supply. And I assume it would improve even more using a switching power supply. In fact the Kill-A-Watt estimated that running my Genesis with the Traco converters would only cost me about $2 a month if left on constantly... then again my power company rate is roughtly $.13 1/2 cents per kilowatt right now which, isn't a bad rate to begin with.

 

Now I realize this thread started off talking about using these in a 2600 and for that I'm sure these would be fine to use on most of the other 8-bit systems. I will still see about installing one into my 7800 and possibly changing out the two on the 5200 as well to see if there is any audible line noise or video interference. Again on the Genesis the s-video was not affected by these at all. I did not test composite but would be able to on the 5200 at least when I install it into that. My 7800 has Magic Knight's s-video kit installed and there isn't any composite for that so it is s-video only for that console. 


Edited by -^CrožBow^-, Tue Mar 21, 2017 9:25 AM.


#54 mojoatomic OFFLINE  

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Posted Tue Mar 21, 2017 9:59 AM

Interesting results. I think it's important to note that RF, AV and s-video will all give potentially different results as to output quality. RF output on the 2600 is in fact cleaner with the Traco's, but that's all I tried. I think it would be interesting to put high and low pass caps on the Traco output and see what your results on the Genesis are. 

 

I have also been experimenting with switching power supplies on the 2600, with good results while using Traco's. Horrible (predictably, I know) without. 

 

There is a tremendous amount of room for improvement on the 2600's as far as filtering, as their filtering is absolutely terrible :-), yet still they work, and have worked for many tears. Atari was so cheap in this area - they did the absolute minimum. Still, for a few pennies in parts, it's AMAZING what you can do. 

 

I've got a 2600 that I've been experimenting with, if there's interest I can post results and video. Of note - I've done nothing to it that couldn't be undone... but I've modded it to pieces. I think you could put a blender on top of it and it wouldn't affect the RF :-) 



#55 Kosmic Stardust OFFLINE  

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Posted Tue Mar 21, 2017 10:18 AM

Okay...so I installed two of the Traco buck converters into my genesis last night. However, I ended up taking them back out...here is why:
 
So first the good -
 
Standard stock supply was showing a constant 20va rating while in use overall draw according to the Kill-A-Watt.
The Power Factor indication was showing a steady .67. My understanding is that you want this closer to 1.0 I believe?
It was showing a usage of 16.8 watts while powered on and running Lightening Force in demo/attract mode.
Actual volts from the adapter was showing it was pulling in a steady 13.9 from the AC directly.
 
With the Traco converters installed I got these readings -
 
16.5 constant overall VA draw
Power Factor was worse showing .51 constant reading. Again I've read you ideally want this closer to 1.0.
It was only using 6.8watts of power...yeap... much less watts being consumed to operate.
Actual voltage being pulled from the AC to the stock adapter was only 8.9. 
 
So with the exception of the Power Factor rating, it would appear that running a set of these in a genesis with a stock power supply will still be quite the improvement in overall power usage and efficiency.
 
Now for the bad...
 
So... the main issue and it was enough to make me put both of the 7805s back in was much louder and whining noise on the audio. Lightening Force (Thunder Force IV) was more obvious and I really couldn't handle it. Additionally, I would also hear a weird rhythmic ticking in the audio line during quiet or silence in the game. And it wasn't a subtle ticking either...very audible and easily picked up. This doesn't happen with the 7805s installed.
 
The other issue and I'm not sure if it related to the Traco converters or not, is that while TF4 played well enough, I was having more issues than I usually do with Sonic 3 just resetting itself randomly within a few minutes of starting a game. This was made worst with Sonic and Knuckles also rebooting itself constantly within about 60sec of starting a game. If you just left Sonic and Knuckles on long enough, it would eventually start to reboot just after the sega logo or right after displaying the title screen logo. With the 7805s in place, this doesn't happen.
 
That said...I have noticed that I can't get Sonic3 and Sonic And Knuckles attached to work on my Genesis at all. It will go through frequently reboots as well, and show corrupted graphics...etc. but only with them docked. Played separately they are fine. This is my test bed genesis and has seen a lot of mods done to it over the years...so it could just..be...tired. It has been recapped as of about 2 years ago so that shouldn't be an issue. But it does appear that the Traco converters on a Genesis at least do work for the most part, but present some very audible noise and ticking in the audio and might have issues with some of the more complex games. One game I didn't try out now that I think about it, is Virtua Racing and I likely should have. I also didn't test with the 32x attached.
 
Honestly with the increased whine in the line level audio and ticks...I just didn't see a point to continue on.
 
However, I can tell you that the s-video picture quality was completely unaffected by the Traco converters and they do run much much cooler. You can touch them easily and they only get warm. But I did notice the one closed to the power connection gets more warm to low level hot as compared to the one closer to the YM2612 location.
 
So...those are the results. Less power required and consumed so it does appear to be much more efficient even with a stock power supply. And I assume it would improve even more using a switching power supply. In fact the Kill-A-Watt estimated that running my Genesis with the Traco converters would only cost me about $2 a month if left on constantly... then again my power company rate is roughtly $.13 1/2 cents per kilowatt right now which, isn't a bad rate to begin with.
 
Now I realize this thread started off talking about using these in a 2600 and for that I'm sure these would be fine to use on most of the other 8-bit systems. I will still see about installing one into my 7800 and possibly changing out the two on the 5200 as well to see if there is any audible line noise or video interference. Again on the Genesis the s-video was not affected by these at all. I did not test composite but would be able to on the 5200 at least when I install it into that. My 7800 has Magic Knight's s-video kit installed and there isn't any composite for that so it is s-video only for that console. 

So the buck supplies do in fact emit more noise when installed versus the stock 7805. If I have to add a bunch of filter caps and junk to the circuit to get it clean, it would defeat the purpose of the upgrade. Honestly the cooler operation is desirable, but not at the expense of excess noise. Have anyone tested these regulators through a "dummy" load such as a resistor or lamp using a scope? I'm curious what the effect would be and the frequency of the ripple, whether it is audible or closer to ntsc frequencies? All my systems are super clean A/V wise except the VCS, and I suspect it's RF related on the Atari. I'm tempted to add an isolation block to the internal coax, as the choke isn't quite cutting it. Could also be cheap coax between the F coupler I installed and the TV. The interference pattern changes when I jiggle the cable.

#56 mojoatomic OFFLINE  

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Posted Tue Mar 21, 2017 10:30 AM

So the buck supplies do in fact emit more noise when installed versus the stock 7805. If I have to add a bunch of filter caps and junk to the circuit to get it clean, it would defeat the purpose of the upgrade. Honestly the cooler operation is desirable, but not at the expense of excess noise. Have anyone tested these regulators through a "dummy" load such as a resistor or lamp using a scope? I'm curious what the effect would be and the frequency of the ripple, whether it is audible or closer to ntsc frequencies? All my systems are super clean A/V wise except the VCS, and I suspect it's RF related on the Atari. I'm tempted to add an isolation block to the internal coax, as the choke isn't quite cutting it. Could also be cheap coax between the F coupler I installed and the TV. The interference pattern changes when I jiggle the cable.

 

You definitely have a bad cable or poor connection / bad component connected to the cable. Also, the choke only helps keeping the cable from acting line an antenna - if the RF is injected and amplified before it gets there, it won't be able to help. 


Edited by mojoatomic, Tue Mar 21, 2017 10:31 AM.


#57 -^CrožBow^- ONLINE  

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Posted Tue Mar 21, 2017 11:01 AM

So the buck supplies do in fact emit more noise when installed versus the stock 7805. If I have to add a bunch of filter caps and junk to the circuit to get it clean, it would defeat the purpose of the upgrade. Honestly the cooler operation is desirable, but not at the expense of excess noise. Have anyone tested these regulators through a "dummy" load such as a resistor or lamp using a scope? I'm curious what the effect would be and the frequency of the ripple, whether it is audible or closer to ntsc frequencies? All my systems are super clean A/V wise except the VCS, and I suspect it's RF related on the Atari. I'm tempted to add an isolation block to the internal coax, as the choke isn't quite cutting it. Could also be cheap coax between the F coupler I installed and the TV. The interference pattern changes when I jiggle the cable.

 

They definitely run MUCH cooler. I even left them standing up a tad to give airflow all around them, but that isn't needed. I could have just soldered them totally flat against the PCB. If you were to use these in a 2600jr, you might have to add small wires to the leads off these converters so you could hot glue them down flat against the PCB. They might stand too tall otherwise. But I don't feel like cracking open my Jr. to check it right now.

 

But yes the much increased line level noise and especially the occasional ticks that were going off was really distracting. Obviously when music was playing on the genesis this noise isn't heard or noticed, but as soon as you click on the power...there it is.

 

I'm going to put one into the 7800 next as that is my next console that just gets crazy hot! I even have a much newer and more efficient 7805 amp model installed, but still amazingly hot it gets. I do have the 7800 AV modded so hopefully the noise isn't there but if it is..I will post it here.


Edited by -^CrožBow^-, Tue Mar 21, 2017 11:04 AM.


#58 -^CrožBow^- ONLINE  

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Posted Tue Mar 21, 2017 11:07 AM

Interesting results. I think it's important to note that RF, AV and s-video will all give potentially different results as to output quality. RF output on the 2600 is in fact cleaner with the Traco's, but that's all I tried. I think it would be interesting to put high and low pass caps on the Traco output and see what your results on the Genesis are. 

 

I have also been experimenting with switching power supplies on the 2600, with good results while using Traco's. Horrible (predictably, I know) without. 

 

There is a tremendous amount of room for improvement on the 2600's as far as filtering, as their filtering is absolutely terrible :-), yet still they work, and have worked for many tears. Atari was so cheap in this area - they did the absolute minimum. Still, for a few pennies in parts, it's AMAZING what you can do. 

 

I've got a 2600 that I've been experimenting with, if there's interest I can post results and video. Of note - I've done nothing to it that couldn't be undone... but I've modded it to pieces. I think you could put a blender on top of it and it wouldn't affect the RF :-) 

 

I've a small stash of caps...have any recommended values to try? And I assume we are only talking about installing them inline off the +5 output right? So..the positive lead on the caps should all point towards the +5 connection?

 

I'm not an engineer so do excuse my ignorance in asking the above. Also I would assume any voltage cap of at least +16 and up is good right?



#59 mojoatomic OFFLINE  

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Posted Tue Mar 21, 2017 11:45 AM

I do have a few suggestions :-) On the 2600

 

Replace C242 with a .22, C243 unchanged, C241 - place 10uf in parallel (observing polarity), C240 unchanged, C239 - place a 10uf in parallel with it (observing polarity) - doesn't matter if the 10uf caps go on the front or back of the board, just keep the leads short. 

 

I need to run this output through a signal analyzer and plot what ferrite bead would be best to suppress noise. This would be to replace the ferrite bead at L204. It will be different for the 7805 and the Traco. 

 

Yes, 16v or up is fine 


Edited by mojoatomic, Tue Mar 21, 2017 11:48 AM.


#60 Kosmic Stardust OFFLINE  

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Posted Fri Mar 24, 2017 1:13 AM

 

You definitely have a bad cable or poor connection / bad component connected to the cable. Also, the choke only helps keeping the cable from acting line an antenna - if the RF is injected and amplified before it gets there, it won't be able to help. 

Are the RadioShack brand Coax RF cables crap? Some of mine have been barely used. Signal is clean as a whistle until I touch something.



#61 mojoatomic OFFLINE  

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Posted Fri Mar 24, 2017 9:19 AM

Are the RadioShack brand Coax RF cables crap? Some of mine have been barely used. Signal is clean as a whistle until I touch something.

Well, I wouldn't talk bad about their stuff, but empiric evidence needs to rule the day. If it goes haywire when you touch it - somethings wrong. 



#62 -^CrožBow^- ONLINE  

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Posted Mon Mar 27, 2017 7:31 PM

Sorry was out of town this weekend. But I've installed one of these into my 7800. Excellent results! It doesn't even appear to get warm, and I notice not interference in audio or through my s-video with it installed. As for power usage, that is an odd thing. Turns out the original 7800 PS is pretty efficient on its own. Plugged into the AC and into the 7800 but with the 7800 turned off, it only uses 4.5v. Turn the 7800 on and it only used up 8.4v while in operation with the stock 7805 in place. Put in the buck converter and it only consumes 7.9 v while in operation. Barely gets warm to the touch, less than 5watts and only .06amps ! .06! That is only 60 milliamps! Needless to the say the 7800 PS isn't warm either since it barely has to do anything current wise to give the converter what it needs to operate. Haven't tested everything like the AVox+ or Harmony, but it has been running 7800 Robotron through the 7800 #1 Anniversary cart for over 3 hours without issue.

 

Guess I should try another system next...



#63 -^CrožBow^- ONLINE  

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Posted Wed Apr 5, 2017 7:36 AM

Again I know this started off discussing the use of these in a 2600 and I apologize if I hijacked Mojo's thread about this. But wanted to state really quickly that I have now installed these converters quite successfully in 4 other consoles without any noticeable graphic or audio issues unlike when they were installed in my Sega Genesis.

 

So I've now installed these into my SNES mini-101, 7800 (Excellent results in both power consumption and essentially no heat), my 5200 (Also virtually no heat nor any interference in graphics or audio), and my Sega Master System. Again, this started off about the 2600, but I did do a video on the process of doing this to my SMS and the power measurements from my kill-a-watt before and after. I also have just a before and after of the power when I did my 5200 but haven't got that video quite ready yet. Just thought it might be of some interest that in most of the classic consoles (At least the 8-bit ones), these really do seem to make a difference. 

 

http://atariage.com/...tor-modupgrade/


Edited by -^CrožBow^-, Wed Apr 5, 2017 7:37 AM.


#64 mojoatomic OFFLINE  

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Posted Wed Apr 5, 2017 9:04 AM

Again I know this started off discussing the use of these in a 2600 and I apologize if I hijacked Mojo's thread about this. But wanted to state really quickly that I have now installed these converters quite successfully in 4 other consoles without any noticeable graphic or audio issues unlike when they were installed in my Sega Genesis.

 

So I've now installed these into my SNES mini-101, 7800 (Excellent results in both power consumption and essentially no heat), my 5200 (Also virtually no heat nor any interference in graphics or audio), and my Sega Master System. Again, this started off about the 2600, but I did do a video on the process of doing this to my SMS and the power measurements from my kill-a-watt before and after. I also have just a before and after of the power when I did my 5200 but haven't got that video quite ready yet. Just thought it might be of some interest that in most of the classic consoles (At least the 8-bit ones), these really do seem to make a difference. 

 

http://atariage.com/...tor-modupgrade/

 

Very cool, they really do work well. 



#65 -^CrožBow^- ONLINE  

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Posted Wed Apr 5, 2017 9:44 AM

I ordered up 2 of the +12 volt variants along with 4 more of the +5 Traco converters today. However, since Allied didn't have any of the +12 in stock, I ended up ordering them from Mouser. The +12 volt models were the same price at Mouser as they were at Allied, but the +5 were about a $1 more each at Mouser. Still to get them all in one place and still for a cheaper price then they are listed on Amazon and on the 'bay, I'm okay with that. I plan to swap in the +12 and +5 Traco's into my composite modded Intellivision and see how it works.

 

BTW...there aren't any regulators inside the actual Colecovision right? Because the various voltages are provided by that boat anchor of a wall tumor right?



#66 Kosmic Stardust OFFLINE  

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Posted Wed Apr 5, 2017 3:22 PM

LOL "boat anchor" and "wall tumor." :lol:



#67 Kosmic Stardust OFFLINE  

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Posted Thu Apr 6, 2017 2:51 AM

Again I know this started off discussing the use of these in a 2600 and I apologize if I hijacked Mojo's thread about this. But wanted to state really quickly that I have now installed these converters quite successfully in 4 other consoles without any noticeable graphic or audio issues unlike when they were installed in my Sega Genesis.
 
So I've now installed these into my SNES mini-101, 7800 (Excellent results in both power consumption and essentially no heat), my 5200 (Also virtually no heat nor any interference in graphics or audio), and my Sega Master System. Again, this started off about the 2600, but I did do a video on the process of doing this to my SMS and the power measurements from my kill-a-watt before and after. I also have just a before and after of the power when I did my 5200 but haven't got that video quite ready yet. Just thought it might be of some interest that in most of the classic consoles (At least the 8-bit ones), these really do seem to make a difference. 
 
http://atariage.com/...tor-modupgrade/

Why was it different with the Genesis???

#68 -^CrožBow^- ONLINE  

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Posted Thu Apr 6, 2017 9:14 AM

Why was it different with the Genesis???

Wish I could answer that...

 

I was using the game Thunder Force IV in my Genesis testing. And that game already has some line level noise that I can hear. But it was amped up by 100% as compared to before and as I stated there was a weird ticking that would occur on occasion. So my guess is that the converters actual placement is the problem. Here is what I mean. In the case of the Genesis, you have two of them side by side about 2 inches apart. But...both of them are near two critical points in the circuit that have to do with the audio and video. The one closest to the power plug on the Genesis is also near the AV out port and the video encoder. Again, I didn't exhibit any perceptible interference on the s-video. But the other, sits only about 1 inch or so from the YM2612. So any RF that they generate that leaks from them, could easily get picked up by the 2612 and then that in turn is getting amped with the rest of the FM signal when it goes to the sony 1034 amplifier chip. I'm sure that with additional capacitors placed on at the least the output voltage line that this could be brought back to near zero noise and interference, but I'm not an electrical engineer, so I would not really know what values..etc to add and where exactly to add them to test it. Also keep in mind that I have a second FM chip piggybacked off the original YM2612 with the YM3438 and that could pickup additional interference easier because of the extra stuff all in that spot. 

 

As I stated before, the SNES already exhibited some line level audio noise even before this. And it doesn't appear that adding in the DC/DC converter made it any worse. If it did, then I'm not noticing it as much as I did with the Genesis. Then again I'm always doing stuff with my Genesis usually involving the audio so I might just be more tuned in with it.

 

Now...to go back to the SMS and 5200 and I suppose the 7800 as well. The converters aren't near the audio circuits as much. In the case of the SMS I mainly use FM audio since I have the add-in board. That is on the opposite side of the SMS from where the power regulation takes place. In the case of the 7800 there is still further distance from the converters location as opposed to where the audio from the TIA is being created. I didn't and should have tested a Pokey game since the Pokey chip in a cart would be closer to the converter than the TIA is on the 7800. On the 5200 the audio is being pulled from further down the system as again, the Pokey is nearly in the opposite corner as the power regulation is. Now, I do have the audio output RCAs and s-video jack right there next to the two converters, but I also have a capacitor on the audio outputs already as it was part of the original required installation. So perhaps the small 10uf capacitor directly off the RCAs is filtering? I'm not sure.

 

But there was definitely something affecting the audio with the Genesis with these installed. 

 

Once I get the other converters in, I suspect the Intellivision will also not suffer any interference because again, the RCA jacks and all the connections from the board to those jacks are on the opposite side from the power supply and regulation area.

 

I do have a quick video I did of the power consumption differences between the 7805s and DC/DC converters on the 5200 but I've feel I have already hijacked this thread enough from Mojoatomic and will post the link to that video comparison in the Blog area.


Edited by -^CrožBow^-, Thu Apr 6, 2017 9:20 AM.


#69 mojoatomic OFFLINE  

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Posted Thu Apr 6, 2017 11:38 AM

 

 

I do have a quick video I did of the power consumption differences between the 7805s and DC/DC converters on the 5200 but I've feel I have already hijacked this thread enough from Mojoatomic and will post the link to that video comparison in the Blog area.

It's not hijacking, just opening up additional avenues of discussion. All of your experiments are directly relateable to the original intent - and so far, the findings indicate that some will work (based on the anatomy of the game systems) and some will not, presumably. 

 

In any case, this mod thus far, applied to Atari and Nintendo systems, appears successful - at least in limited testing.  

 

 

I do have a few suggestions :-) On the 2600

 

Replace C242 with a .22, C243 unchanged, C241 - place 10uf in parallel (observing polarity), C240 unchanged, C239 - place a 10uf in parallel with it (observing polarity) - doesn't matter if the 10uf caps go on the front or back of the board, just keep the leads short. 

 

I need to run this output through a signal analyzer and plot what ferrite bead would be best to suppress noise. This would be to replace the ferrite bead at L204. It will be different for the 7805 and the Traco. 

 

Yes, 16v or up is fine 

 

On another note - have you tried this? See what you think :-) 



#70 -^CrožBow^- ONLINE  

-^CrožBow^-

    Quadrunner

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  • Location:Ivory Tower, Fantasia (Oklahoma)

Posted Thu Apr 6, 2017 1:02 PM

LOL "boat anchor" and "wall tumor." :lol:

Well it is easily the heaviest power supply of any classic system I own, and the sheer size of it I figured made the more common term of Wall Wart not really qualify for it. So..yeah....



#71 SignGuy81 OFFLINE  

SignGuy81

    Dragonstomper

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Posted Sat Apr 8, 2017 7:23 PM

I'm thinking it may help to to try to wrap the converter in foil tape, just being careful not to get too close to the pins. 



#72 Osgeld ONLINE  

Osgeld

    River Patroller

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Posted Sat Apr 8, 2017 7:50 PM

you can sheild it in the above method but be sure to ground it or you just made a antenna to make it worse 



#73 SignGuy81 OFFLINE  

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    Dragonstomper

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Posted Sat Apr 8, 2017 8:17 PM

you can sheild it in the above method but be sure to ground it or you just made a antenna to make it worse 

true



#74 -^CrožBow^- ONLINE  

-^CrožBow^-

    Quadrunner

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  • Location:Ivory Tower, Fantasia (Oklahoma)

Posted Sat Apr 8, 2017 8:34 PM

I'm thinking it may help to to try to wrap the converter in foil tape, just being careful not to get too close to the pins. 

 

You mean, I might have another use for the foil tape I have like a TON of that I use to refurbish my 5200 controllers? Hmm. Actually if you press them all the way to the PCB, then the pins are pretty much covered.

 

But this also explains why on the 7800 and 5200 especially, that there isn't any noise or interference. Because I still have the shielding on those two consoles?! So all the ICs are still under their nice little metal shields while the converters are outside the mix. On the Genesis, I also still have the shielding in place, but the area where the converters are is one large opening without the heatsink there. And no, there isn't room for the heat sink to go back on plus the DC/DC Converters. 

 

Oh...I just did the swap out on my Intellivision. Just about to get the measurements off the Kill-a-Watt with the new converters in place.



#75 Kosmic Stardust OFFLINE  

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Posted Sat Apr 8, 2017 8:42 PM

 

You mean, I might have another use for the foil tape I have like a TON of that I use to refurbish my 5200 controllers? Hmm. Actually if you press them all the way to the PCB, then the pins are pretty much covered.

 

But this also explains why on the 7800 and 5200 especially, that there isn't any noise or interference. Because I still have the shielding on those two consoles?! So all the ICs are still under their nice little metal shields while the converters are outside the mix. On the Genesis, I also still have the shielding in place, but the area where the converters are is one large opening without the heatsink there. And no, there isn't room for the heat sink to go back on plus the DC/DC Converters. 

 

Oh...I just did the swap out on my Intellivision. Just about to get the measurements off the Kill-a-Watt with the new converters in place.

Meh. Most of my consoles still have their shielding intact, except the NES, mainly due to the CopyUSB and BLW not fitting properly woth them in place... :P

 

I always though the shielding was more about complying with FCC than reducing noise. If you think about it, you've got the RF and AV circuits sitting right underneath the shield with all the other interference causing circuits. The faraday cage won't protect it against itself.






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