Author Topic: need PC engine GT Q500 transistor replacement part??  (Read 4235 times)

bdoi

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need PC engine GT Q500 transistor replacement part??
« on: October 23, 2019, 12:47:58 PM »
Hello

I have a GT fully reccaped with sound but no display. I point the transistor Q500 which become really hot when I power on the console.
does anyone knows the Q500 ref or a working replacement part?

thanks in advance for your help


Keith Courage

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« Last Edit: October 24, 2019, 09:33:36 PM by Keith Courage »

bdoi

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Re: need PC engine GT Q500 transistor replacement part??
« Reply #2 on: October 26, 2019, 02:44:43 PM »
Thanks I will order this and try it . Finger crossed :pray:

Keith Courage

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Re: need PC engine GT Q500 transistor replacement part??
« Reply #3 on: October 27, 2019, 08:03:51 AM »
Was the part damaged from old capacitor leakage or did it just fry on its own? If it fried on its own then the Transformer on the board is shorted out and needs replacing. Also, if you didn't order yet I have some extras of that transistor. I wasn't sure if you just needed 1 or if your question was about needing to know for future reference what to order anytime you come across a bad one.
« Last Edit: October 27, 2019, 09:14:47 PM by Keith Courage »

bdoi

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Re: need PC engine GT Q500 transistor replacement part??
« Reply #4 on: November 01, 2019, 03:51:33 PM »
I think the part wasn't damage form old capacitor leakage.
So you think the transformer is shorted too... Is it the big square just under the CC900?

Keith Courage

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Re: need PC engine GT Q500 transistor replacement part??
« Reply #5 on: November 03, 2019, 03:10:51 PM »
Unfortunately yes that is the part. Does the system still turn on? Can you hear sound?

bdoi

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Re: need PC engine GT Q500 transistor replacement part??
« Reply #6 on: November 07, 2019, 04:14:26 PM »
Yes there is still sound . In fact I just tried for few second and feel the q500 getting really hot so I have turned it off. I am waiting for the ordered transistors . As soon as I would received it I will try to change the transformer in the same time and will let you know the result.
« Last Edit: November 08, 2019, 04:10:49 AM by bdoi »

Keith Courage

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Re: need PC engine GT Q500 transistor replacement part??
« Reply #7 on: November 07, 2019, 07:47:42 PM »
Well, the good news is that since your express still powers on with sound, you could always go the replacement screen route using the composite video mod if you are unable to get things going with the original.

bdoi

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Re: need PC engine GT Q500 transistor replacement part??
« Reply #8 on: November 08, 2019, 04:10:23 AM »
Yes it was my plan if the transistor and transformer replacement  don't work.
But it looks really tricky to do :(
« Last Edit: November 08, 2019, 09:38:52 AM by bdoi »

Keith Courage

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Re: need PC engine GT Q500 transistor replacement part??
« Reply #9 on: November 09, 2019, 04:22:02 PM »
Yeah, the composite mod for a larger screen is difficult and risky if one hasn't ever soldered on small pins like that before. I do these mods if it's something you don't want to tackle.

bdoi

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Re: need PC engine GT Q500 transistor replacement part??
« Reply #10 on: November 09, 2019, 04:27:51 PM »
Thanks for the proposition , I will keep this idea in mind. But I am in europe so shipping oversea is really expensive:(

bdoi

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Re: need PC engine GT Q500 transistor replacement part??
« Reply #11 on: November 13, 2019, 04:48:44 PM »
I tried to replace the q500, nothing better, replace the transformer, nothing better.
I also tried to replace q900 and q901, same thing  :-\
I have no other solution to try the lcd screen mod

Keith Courage

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Re: need PC engine GT Q500 transistor replacement part??
« Reply #12 on: November 14, 2019, 10:26:37 PM »
Not sure if any place in the Uk sells the composite out board but they can be bought here.  https://tg16pcemods.ecwid.com/#!/TURBO-EXPRESS-PCE-GT-COMPOSITE-VIDEO-BOARD/p/100968130/category=0

This is to make the system put out composite video. It can then have a 2.5" or 3.5" screen installed.

I'd start by installing this board first and then just use a RCA cable to test with your TV to make sure you are getting good video.

If you feel comfortable enough to build your own composite board then here are the components needed.

« Last Edit: November 14, 2019, 10:28:42 PM by Keith Courage »

bdoi

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Re: need PC engine GT Q500 transistor replacement part??
« Reply #13 on: November 15, 2019, 02:13:57 AM »
Thanks
I saw there are 2 versions : composite and S-Video?
« Last Edit: November 15, 2019, 02:16:00 AM by bdoi »

Keith Courage

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Re: need PC engine GT Q500 transistor replacement part??
« Reply #14 on: November 15, 2019, 11:11:25 PM »
Well, the s-video would be if you plan to also hook the express up to a TV. I have yet to find a good screen for the express that will take a S-video signal so no reason to go that route unless you plan to use it with a TV that can use s-video. These 3.5mm screens from console 5 are excellent for composite video. They are what I use now. https://console5.com/store/universal-3-5-composite-video-lcd-module-320x240.html

Console 5 also sells the new larger size screen protectors. https://console5.com/store/turboexpress-3-5-glass-lens-screen-cover-for-lcd-swaps-turbo-express.html but they can be bought for less here https://www.ebay.com/itm/Turbo-Express-3-5-lcd-Glass-screen-protector-NEC-pc-engine/233246430957?hash=item364e9216ed:g:rfQAAOSwbzpc9WUO
« Last Edit: November 15, 2019, 11:15:40 PM by Keith Courage »