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Stephen Moss

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About Stephen Moss

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  • Birthday 12/20/1970

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    Cambridge, United Kingdom
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    American Football, Golf, Electronics, Programming, Sci-Fi, Indoor Climbing

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  1. Sorry, I forgot to check but the connector are on a 0.1 inch (2.54mm) pitch.
  2. Take 5V and 0V from the appropriate ends of C39, that should be easily accessible. It is not quite as simple as that as you need to generate a 20V supply, see my fuller reply here.
  3. If you look at the schematic you will see that the power for the LCD/contrast circuit comes from a tap on the primary side of the transformer (Lynx 2) or secondary of the power module (Lynx 1) and that the supply voltage for that circuit at TP12 is 20V. Consequently although you could try powering it from 9V taken from D11 (Lynx 2 ) or D18? (Lynx 1) it may not work well, if at all, and so you would need to install a boost type switching regulator to convert 5V or 9V to 20V if you are set on removing the coil and patch it in to TP12. But why remove it when doing so will cause more problems than it is worth? I presume the power connection for the original backlight is provided via a connector (it is on the Lynx 2), thus with nothing plugged into that connector there and therefore nothing connected to the output of the transformer that would be drawing current, the difference in current consumption between leaving the transformer in over removing it it negligible.
  4. I presume it is for the forint panel button membrane in which case it is an FCC (Flexible Circuit Connector) type. Try searching of 14 way FCC connector, you should be able to get them from most large component suppliers. However you need to workout the pitch of the connections, usually the wider the pitch the bigger the connector so you could go on connector size but just measure the number of connections over a 1 or 2cm or 1 inch and divide to get the pitch on mm or inches. If I can I will post a pitch later.
  5. Unless a second identical serial number sticker was attached to the PCB during assembly any kind of identification number printed directly on the PCB it is likely to be a manufacturing batch number/date code added by the production house for quality control (i.e. recall a batch of faulty boards) and so an unknown number of boards would have the same number on them. So if you alone took that approach it would be OK and you may have a unique serial number, but if anyone else copies that approach then there could be multiple Lynx's out there with the same serial number.
  6. I think that may generally a better option than tinning with solder because unless you are good at soldering... a) It is can be difficult to get a good thin layer of solder and too think a layer or any lumps may over time result in bending or scratching of the contacts in the cartridge connector resulting in poor contact with those cartridges you have not "tinned" with solder. b) In trying to get a nice thin lump free layer of solder you risk heating up the card edge fingers to the point where they become unglued from the PCB. c) If you decant the ink from the pen into a small pot/jar/bottle cap and use a small paintbrush (i.e. for painting models) you should be able to apply the ink without having to take the cartridge apart as you would probably have to do if soldering/using a conductive ink pen to gain full access to entire area of the card edge finger contacts.
  7. With the pins nearest to you and the tab furthest from you left to right is Input, GND, Output. For the voltage regulator to output 5V it needs an input of 8V or more, as the input voltage drops below 5V the output voltage is generally the same as the input. Therefore if you have 3.2V in and 0.2V out that suggests to me that you might have a short Circuit somewhere. I would suggest desoldering the output pin of the regulator and when certain there is no connection between it and the rest of power rail switch on and measure the output voltage, if is it 5V then your problem is after the regulator, if still at 0.2V then it is at or before the regulator.
  8. You could try 1000pF (1nF) but it may be a bit too far from the intended value to give the correct results... If you can get 470pF and 330pF then connect them in parallel to get 800pF, two 470 may be more cost effective as you often have to purchase them in at least a multiple of 5 but is a bit further off the desired value at 940pF. Alternatively if you can get a 1600pF (1.6nF) and a 1800pF (1.8nF) and wire them in series that will give 847pF.
  9. Are you getting snow/static of black screen? If the latter then if the voltages DrVenkman mentioned check out I suggest checking that the voltage on the RES (Reset) pins of the 6507 (pin 1) and the RIOT (pin 34) are 5V.
  10. When you say 7.7V on C41 was that measured directly across it or just at one end? Why measure the voltage across TP18 and TP19? I fail to see how that would be of any relevance. Same question as above regarding C41 voltage and did the Lynx power up as soon as a power source was connected
  11. @ Dave 222004, unfortunately, that 2KV transformer for the backlight is right where you fingers goes when holding the Lynx 2 which I also found out the hard way, numbed the end of my finger for about 30 minutes. Not an easy area of the circuit to diagnose problems with as most people would not have access to the required equipment. But what you can do is start by... 1) Look with a magnifying glass around that area for signs of blackening to the PCB or components that appear broken/hole or indentation in them. If there was a short somewhere, particularly of the 2KV then a visual inspection may reveal any resulting damage. 2) You should be able to see the ends of the LCD backlight, is the back light on and if so how bright is it and can you switch it on and off? 3) If you have a multi-meter can you measure the voltage across C23? The schematic indicates it should be around 20V but I cannot provide a comparison measurement as my Lynx is at work I will not be until sometime in September.
  12. First, if that Amazon link is correct the reviews are not good and strongly suggest the the input voltage is the same as the output voltage, also the general description indicates that the output voltage is 1.25-36V which both explains the present pot (blue component with screw on) and why there is no thread lock on it to prevent adjustment. Obviously, I have no idea what the reviews were trying to do but as it the output is adjustable I strongly recommend measuring it (and adjusting as necessary) if you have not already done so before connecting it to your console to prevent potentially damaging the console if the output is initially set higher than 3.3V. Second, the DC-DC converter used in the linked videos is a different type, it has a fixed output and look like it would have the necessary filtering and smoothing built in. Third, the items you think are fuses have a resistance values (0.22 & 22 Ohms) printed on them. Although it is not impossible to use resistors as fuses by relying on them burning out to protect the circuit, I may be wrong but I don't think these are fuse resistors as there resistance values, wattage (going by size) as the maths does not appear to support that. 4th, between the linked video and image posting in the Redit link I have surmised the following... 1) The 220uF cap on the 12V and 470uF cap on 3.3V line are for smoothing the DC voltage, not for filtering any switching noise. If you want to use any of the caps you provided images for in place of those use the two 680uF, put the 10V one on the 3.3V line and the 35V on the 12V line. 2) The Redit pic shows two fuses, it looks like one is on the 12V line to the Connector (after the 12V connection to the DC-DC converter) which protects the the 12V circuity and one on the 3.3V output of the DC-DC converter protecting the 3.3V circuity. That makes sense, although as I stated previously I would also put one between the 12V supply so that you have... Fuse 1) 12V DC to Input of DC -DC converter - if this blows then you have a problem with the DC-DC converter and 12V supply should be protected from that. Fuse 2) 12V to 12V pin of Connector - if this blows then you have a problem with the 12V circuitry in the console and 12V supply should be protected from that. Fuse 3) 3.3V to 3.3V pin of Connector - if this blows then you have a problem with the 3.3V circuitry in the console and the DC-DC should be protected from that. You could do away with fuse 1 and connect both the input of the DC-DC converter and the connector 12V to the output side of the 12V fuse but the three fuse method is better, If using a traditional fuse I would go for 20mmx5mm or 32x6.3mm (1/14" x 1/4") glass because you can often visually see that they have blown without using a multi-meter (break in wire, or glass blackened/spattered with metal). Fast blow (F) may be sufficient, although if using those 680uF caps instead of the 220 & 470uF caps suggested by the sources you quoted as extra smoothing then Anti-Surge(T) may be better, the extra in rush current of the larger caps will probably be OK for fast blow, but going anti-surge will remove the possibility of the inrush blowing the fuses. The rated current on fuses is the hold current, the blow current of often much higher so for values I would suggest... Fuse 1) Not entirely sure what he correct value is for this, it really depends on knowing input to output current ratio, but as we do not know that and as you will need a multi-meter to set the output voltage of your DC-DC converter the you can simply measure it to determine the required value. If you are lucky it will be close enough to the value of either Fuse 2 or two of Fuse 2 wired in parallel (not tried it but I think it should work) to create 1.5A/2A option. It cannot be greater than 2A otherwise you will overload your 12V @ 3A supply, if you use parallel fuses instead of buying an extra one of the correct value then always replace them in pairs even if just one appears blown. Fuse 2) The moulding on the case indicates 0.8A (800mA), if you can find that then use it otherwise the closest will probably be 750mA or 1A. Given those options I personally would try 750mA first, I expect it will hold (but may be a little stressed & occasionally fail through fatigue) and is a little safer that using the larger 1A, but if it blows frequently then swap to 1A. Alternative you could just go for the 1A from the get go. Fuse 3) The moulding on the case indicates 2.7A, if you can find that then use it but your likely available options will be either 2.5A or 3A. Given those options I would try the smaller one first for the same reasons given for fuse 2. Finally, are you sure you have wired everything up correctly? The reason I ask are... a) You appear to be using Black wires for the 12V & 3.3V supply and Red wires for GND, traditionally those colours are reversed. b) Your Red GND connection from the DC-DC converter appears to be connected to the positive side of the capacitor instead of the negative side (stripe down side is usually negative unless indicated otherwise).
  13. People may be able to help more if they know what circuit you were following and/or which buck converter IC you were using. I know you said you have the caps sorted but just in case... For Cap voltage anything more that the expected voltage across them is good (less and they won't last long), double will give you plenty of overhead but if you are limited for space you might have to go with a voltage a little lower than double (physically smaller). Caps are short circuit to AC but open to DC, unless there is specific reason for them to be connected otherwise always connect caps between the supply voltage and GND. If the capacitor on the supply output is for smoothing then they should definitely go to GND. Generally the larger the capacitor the more smoothing you get and the larger the current draw the larger the capacitor you need. I am not sure where you got the current values mentioned from and if you search the web I am sure you will find the correct calculations for determining the correct capacitor values for the applicable switching frequency and current draw. However, if the caps are for filtering then a 0.1uF disc to ground may help but you may need to research passive low pass filters to cut out all the switching noise from the buck regulator output (if filtering is not built in to it) otherwise you may find the switching noise creates noticeable interference on the audio and/or video. AS for the fuses, if I understand your diagram correctly then I would place... a) One fuse between the output of your 12V 3 A switching supply and the power connector 12V in line b) One fuse between the output of your 12V 3 A switching supply and the Buck converter input and c) One immediately after the output of your Buck circuit. Those are the same thing, a 5A supply will not put 5A down the power rail regardless, it will only do so if the connected circuit pulls that much current from it. If a power supply can supply 5A but the connected circuit only draws 1 amp then a 1 amp fuse should be used, because if a problem arises with the circuit the fuse will blow at around 1.5A both protecting the power supply and limiting the amount of damage done to the circuit keeping it repairable. Whereas if you were to use a 5A fuse, it would not blow until 6A of current are being drawn, it may just be enough to project the supply but the circuit would be very crispy and possibly damaged beyond repair. If nobody knows the correct fuse sizes and you cannot find an schematic which shows them, you will need to use a multi-meter it to measure the current being drawn, that will indicate what size fuse you need.
  14. I waited to post a reply in case somebody actually knew what this was as I have no idea. It is difficult to get a good idea of the size, particularly in relation to game boxes but to me the wording suggests that is may have been something that was intended to be added to cartridge boxes post production to promote sales of a particular game(s) by indicating it was used at the championships. Maybe there was going to be some sort of additional marking to go with it along the lines of... Couldn't compete? See if you can you beat the world champions score in the official championship game(s)?
  15. What exactly are you trying to do here? If you are trying to replace the analogue pots with digital pots for use with the 2600 that will not work. A digital pot (assuming we are talking about the IC) acts as a potentiometer and so outputs a variable voltage. However, the 2600 uses the analogue pots as variable resistor (not as a potentiometer) that varies the amount of current used (and therefore time taken) to charge a capacitor. There is no direct correlation between the two methods, with a Microcontroller you can potentially read the voltage of an analogue potentiometer, use that to calculate its resistance and then calculate and set the appropriate output (can't remember if the paddle read is voltage or timer triggered) at the appropriate time, but to me that is a lot of pointless time and effort compared to just using an analogue pot as originally intended. That could be a bit of a problem as any solution someone gives you will probably involve a schematic of the circuit.
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