Lynx 2 - Dim screen on cold boot, then returns after 15 minutes?

[Fabthegnome]

Hello, I've used these forums as a resource for many years, but this is my first time posting here, so hi there!

 

Today I received a new old stock console, but unfortunately after powering on the console for the first time the screen appeared dead, but then on closer inspection it was view-able, but only with the assistance of a flash light.

 

(see here)

 

I then left the console on and went away for about 20 minutes, on my return the screen was just the opposite, it was so bright i had to turn down the brightness/contrast right away!

 

Oh, and I did test switching the console off/on after, waiting several minute in between and still the display continued functioning as it should.

 

 

I can't say if the issue will ever return as the consoles not been in my possession for more than several hours, but I wanted to ask here if anyone could provide an explanation?

Edited June 28, 2018 by Fabthegnome

[+Stephen Moss]

Sounds like it could be a problem with the Backlight or High Voltage transformer/Capacitor. You could try changing the capacitor that is between the output of the HV Transformer and the backlight bulb to see if that cures it.

You could also try measuring the output of the transformer but be careful as it is about 2000V and will certainly make a bang if you short out or give you a nasty nip if you touch it.

[Fabthegnome]

Thank you for the advice, forgive me, my knowledge of electronics is rather limited, but can such a transformer hold a charge while the console is off?

 

I left the console powered off for 12+ hours and had no issues powering up the console again, I'm now going to leave it for the next 24 hours and see if I can replicate the issue.

 

Oh, I've also been in touch with the seller and he reports no such issues when the unit was tested 2 months ago, now the console did spend about 5 days in transit, wrapped in ordinary bubble wrap, is there a chance damage from static could have been the culprit?

[Fabthegnome]

Update

 

I've been unable to replicate the issue so far, after leaving the unit powered off for about 30 hours, I was able to turn the console on again without a problem.

 

So I'm still no closer to understanding the issue it seems.

[+Stephen Moss]

Thank you for the advice, forgive me, my knowledge of electronics is rather limited, but can such a transformer hold a charge while the console is off?

 

I left the console powered off for 12+ hours and had no issues powering up the console again, I'm now going to leave it for the next 24 hours and see if I can replicate the issue.

 

Oh, I've also been in touch with the seller and he reports no such issues when the unit was tested 2 months ago, now the console did spend about 5 days in transit, wrapped in ordinary bubble wrap, is there a chance damage from static could have been the culprit?

 

Transformers cannot hold charge although the capacitor in the circuit can, however when the lynx is powered off with the backlight on I would expect most if not all of the charge to be used by the backlight trying to stay on and thus be consumed within a second.

 

I must admit I have never tried rubbing bubble wrap together to see if it get a static charge, even if it can most of the Lynx is plastic so there would be almost nowhere it could discharge to so I think you would be very unfortunate for that to be an issue.

 

I am sure you have seen florescent tubes start off dull and then gradually brighten up, although that could possible be due to a lack of gas I think (but an not absolutely certain) the main reason is the components in the starter fail and so produces a charge that is not sufficient to energise all the gas in the tube immediately and so the tube is dim, eventually a cascade effect takes place energising the remaining gas and the tube brightens.

 

Someone recently posted a fault where the solder on the legs of the capacitor in the backlight circuit became so hot it melted and bubbled (at least 300 centigrade) which was probably due to a short circuit of the capacitor allowing a large current to flow. As capacitor get old they can go open or short circuit, as they do their value and ability to hold charge will change. I think the backlight for the LDC is essentially a fluorescent tube thus, the less charge the capacitor can hold the less of a kick it can give to the gas in the tube to make it light. At least that is my theory and hence why i initially suggested looking at the part or the circuit.

 

Sometimes, some capacitors that have not been used for a can reform to their original state with use which may explain why you are not having the problem anymore, the problem with intermittent faults is they are hard to diagnose being there one minute and gone the next.

If it was my Lynx, then with no other information pointing the problem to being elsewhere I would be inclined to change the capacitor anyway, just in case that was the culprit.

[Fabthegnome]

Sometimes, some capacitors that have not been used for a can reform to their original state with use which may explain why you are not having the problem anymore, the problem with intermittent faults is they are hard to diagnose being there one minute and gone the next.

If it was my Lynx, then with no other information pointing the problem to being elsewhere I would be inclined to change the capacitor anyway, just in case that was the culprit.

Thank you so much for your detailed response, in your experience are these sort of faults (assuming it is related to bad caps) becoming more frequent as these consoles age? I've had to replace caps in a game gear and turbo express so far, but not heard of too many lynx consoles having serious issues.

 

The seller has given me the option of returning the unit for a replacement, do you think it would be wise to take him up on the offer or perhaps discuses the seller covering costs for the necessary repair work? I imagine with time, any such replacement could start to present similar issues, no?

 

Oh, and some what unrelated, but as I'm not experience enough to do the recap myself, if I'm going to be shipping my console back and forth for repair, would it just be worth having something like the mcwill lcd installed now?

 

Thanks again.

[+Stephen Moss]

Thank you so much for your detailed response, in your experience are these sort of faults (assuming it is related to bad caps) becoming more frequent as these consoles age? I've had to replace caps in a game gear and turbo express so far, but not heard of too many lynx consoles having serious issues.

 

The seller has given me the option of returning the unit for a replacement, do you think it would be wise to take him up on the offer or perhaps discuses the seller covering costs for the necessary repair work? I imagine with time, any such replacement could start to present similar issues, no?

 

Oh, and some what unrelated, but as I'm not experience enough to do the recap myself, if I'm going to be shipping my console back and forth for repair, would it just be worth having something like the mcwill lcd installed now?

 

Thanks again.

It is difficult to tell if faults caused by caps are becoming more common, there tends to be a culture here of blaming bad caps for everything, then people change them based on such erroneous comments only to find the problem still exists because it was not the caps at all. In reality caps rarely go bad unless they are part of a bad batch when manufactured or have been exposed to adverse conditions. However in this case given the symptoms described there is a logical reason for speculating that the cap may be at fault.

Generally, capacitors are very reliable having a lifetime of at least 100,000 hours of use but many factors can affect that such as manufacturing faults, exposure to extreme temperatures, overvoltage, frequency of use or being run at the limits of their operational specifications. Electrolytic caps are generally more prone to going bad in that if not used for extensive periods (probably talking of 10 years or more) something happens chemically to the electrolyte material but they can reform with use. We have equipment here that is 30 years old and only used for say 5 hours a year at most and the caps are still fine.

 

Personally if the seller has another working unit I would be inclined to take up thier offer of an exchange as it immediately solves the problem and is simpler for the seller as they are just exchanging like for like. Yes, there is always the possibility that the replacement they send may develop the same or a different fault, but faults are to be expected as when built production technique were not as good as they are now & they were never designed for this level of longevity expecting most users to grow out of gaming within 10 years as they aged and other priorities in life took over.

Trying to get the seller to agree to fund a repair could be more difficult as the cost of that is unknown, it may be the cap, the black light bulb itself or something completely different, without doing a thorough investigation the cap and bulb to me seem the most obvious places to look given the symptoms described but with electronics the obvious is not necessarly the correct as something further down the line (i.e. power regulation) could be causing the issue.

Consequently if the seller is not capable of diagnosing and repairing the Lynx themselves then depending on how reasonable they are willing to be it could take some time before the two of you can agree on who should do the work, and how much the seller should contribute to the cost or repair if that was the route you wanted to take.

 

Personally if I was shipping the unit off for repair and wanted a McWill screen replacement fitted then assuming the person I was shipping it to was competent enough to do the repair then I would think they should be able to fit the McWill screen replacement, consequently if I had the necessary funds to do so I would have them done at the same time.

From a practical point of view getting them done together means the Lynx is only being disassemled once so less chance of a screw piller being broken or screw pillar thread being stripped so the screw no longer grips, I would only paying to ship it off and back once thereby saving on shipping fees & overall it would probably be out of my possession for less time.

 

But that is just what I would do, you have to balance the risk/cost of purchasing a McWill screen replacement kit now with a view to having it fitted at the same time as the repair with the possibility of not having a working Lynx to fit it in if the person you send it to cannot find the fault against that of sending it to hopefully be repaired first.

If have not looked too closely at what is required to fit the McWill screen upgrade but if it does not use the existing screen backlight or HV circuit then another potential advantage of getting them done at the same time is that if the problem was diagnosed as being with the existing HV circuit/backlight they can simply be disconnected without needing to be repaired if they are no longer used.

[Fabthegnome]

Heh, again, it's much appreciated you taking all this time to give advice.

 

I spoke with the seller and asked about covering costs for a recap, he declined, but offered to send out a replacement without me even having to send the old console back! I certainly couldn't argue with that. : D

 

The replacement will be new old stock too, so I wouldn't be surprised if there are similar issues, that said this would confirm your suspicions of bad electrolytic caps.

 

It's quite an interesting story, the seller was in fact developing a game for the Lynx, unfortunately the console ceased production before he finished, which lead him to purchasing a whole bunch of discounted stock. I believe he even has a prototype cartridge of said game for sale.

 

..now what on earth do I do with two consoles, any multiplayer recommendations? XD

[+-^CrossBow^-]

..now what on earth do I do with two consoles, any multiplayer recommendations? XD

 

Warbirds and Todd's Adventures in Slime World come to mind... There several Lynx multiplayer games out there, just need to get a comlynx cable to connnect the two along with two copies of the games of course.

 

To provide a little more information on your questions you've posed...

 

Getting the McWill LCD upgrade does require removal of the HV circuit since none of it is required for the new screen replacement. So the backlight and old lcd are removed. But I wouldn't recommend just getting the McWill installed without also going ahead with a recap of the system and replacement of the power mosfet and zener diode as well. While it is true that caps have a decent life span, it is also well known how craptastic the caps of the 90s were. I can say however, that Atari may not have put much resources into development of games for their systems, but they did for the most part build quality hardware. I can't recall the original quality of the caps on the Lynx, but I don't believe I've ever seen any that were leaking on the few lynx systems I've recapped. And in the case of the Jaguar and JagCD, Atari actually used high quality Nichicon caps in that console!

 

But yes, I would advise that if you send your lynx to get a McWill LCD upgrade (and it is highly recommended if you can afford it), that the person doing the work should recap and replace the other components I mentioned as well. If the system is already apart for the McWill mod, then there isn't much of an excuse to NOT do the other work as well. Preventive maintenance and all that, and if you are going to spend the money, you want to make sure it will last another 20+.