Forums

Hello all. I have a Sega Master System that I've had for about the last 20 years. A year or two ago I pulled it out of the closet to play and couldn't find the right AC adapter. Since my original one #3025 had the wires frayed I had just assumed that I was using my Genesis adapter. When I plugged that in, I remember the power light being faint and no games would work, I may have even tried my NES AC adapter to no avail. At this point I do remember smelling a slight burning smell but no smoke.

After that I went to Radio shack and purchased an adapter that matched the original, 1Milliamp, 9 volts, negative tip. The system will still not turn the green light on. I have taken it completely apart since then looked at the circuit board and see no visible burnt solder marks or anything. Is there a way to troubleshoot these with an ohm meter/volt meter?

Anyways, I have a Genesis with the Power Base Converter so I can still enjoy my SMS games, just wondering if I could get the old SMS to work for old time's sake.

The AC might have killed it. The faint LED suggests it might have had problems anyway.

Hmmm... looks that when you tried to put the N*S PSU on the SMS, you fried the 7805 (+5V) Voltage Regulator... This is a very very common and cheap component, even here in Brazil, and it looks like a MOSFET like transistor, easy to replace...

It also looks like you have a problem with bad capacitors on the system, looks for some leaky or stuffed ones, and try looking at broken lines on the board...

Some models, like Tec Toy SMS have a bad fenolite board, that the copper tracks lifts from the board, and gets very fragile, and usuallys breaks lines...

If you have a Multimeter (or at least a voltmeter), you may try to check diodes from the power supply section, and also if's there +5V at all on some parts of the board to verify the problem

sst1226 wrote

After that I went to Radio shack and purchased an adapter that matched the original, 1Milliamp, 9 volts, negative tip. The system will still not turn the green light on. I have taken it completely apart since then looked at the circuit board and see no visible burnt solder marks or anything. Is there a way to troubleshoot these with an ohm meter/volt meter?

Err.. I assume you mean 9 volt 1 amp, as 1ma would be rediculously small. The original adaptor (at least for Austalia) is 9v 850mA.

Yes its 9 volt, 1amp. I'm pretty sure the bottom of my sega says 9 volt 850ma for required power but the adapter that came with the system says 9 volt, 1 amp

Never use a NES AC adapter with anything but a NES...

Even though the voltage info seems the same, I fried my first SEGA CD system when I was 8 with one...

I am 22 now and will never make that mistake again with my precious Sega collection...

there is something about that certain Ni****do AC adapter that is off, maybe the voltage and amperage info on it is wrong or slightly off? IDK

On a related note, you can however use a SMS AC adapter with a Sega CD system (or model 1 genesis), I am doing that currently till I buy a Sega CD/Model 1 genesis AC adapter for it...

segamanxero wrote

Never use a NES AC adapter with anything but a NES...

Even though the voltage info seems the same, I fried my first SEGA CD system when I was 8 with one...

I am 22 now and will never make that mistake again with my precious Sega collection...

there is something about that certain Ni****do AC adapter that is off, maybe the voltage and amperage info on it is wrong or slightly off? IDK

On a related note, you can however use a SMS AC adapter with a Sega CD system (or model 1 genesis), I am doing that currently till I buy a Sega CD/Model 1 genesis AC adapter for it...

The problem with the NES power cord is that it brings the voltage down to wherever it needs to be, but it keeps it in AC. Its brought into DC inside the console itself. if you use a genesis power adaptor on an nes, it just passes through the DC. imagine turing on and off your sms 60 times a second.

Rony_ket wrote

Hmmm... looks that when you tried to put the N*S PSU on the SMS, you fried the 7805 (+5V) Voltage Regulator... This is a very very common and cheap component, even here in Brazil, and it looks like a MOSFET like transistor, easy to replace...

It also looks like you have a problem with bad capacitors on the system, looks for some leaky or stuffed ones, and try looking at broken lines on the board...

Some models, like Tec Toy SMS have a bad fenolite board, that the copper tracks lifts from the board, and gets very fragile, and usuallys breaks lines...

If you have a Multimeter (or at least a voltmeter), you may try to check diodes from the power supply section, and also if's there +5V at all on some parts of the board to verify the problem

Ordered the voltage regulator and from radio shack, soldered the new one in and I'm back up and running after having it sit around for over seven years. Plugged it in last night, played some Snail Maze, Astro Warrior, Hang-on and Space Harrier. It was great re living those childhood memories on a 60" flat screen. Thanks again!

Author	Message
sst1226 Joined: 06 Mar 2009 Posts: 5	Sega Master System Doesn't Work Posted: Tue Mar 17, 2009 6:25 pm
sst1226 Joined: 06 Mar 2009 Posts: 5	Hello all. I have a Sega Master System that I've had for about the last 20 years. A year or two ago I pulled it out of the closet to play and couldn't find the right AC adapter. Since my original one #3025 had the wires frayed I had just assumed that I was using my Genesis adapter. When I plugged that in, I remember the power light being faint and no games would work, I may have even tried my NES AC adapter to no avail. At this point I do remember smelling a slight burning smell but no smoke. After that I went to Radio shack and purchased an adapter that matched the original, 1Milliamp, 9 volts, negative tip. The system will still not turn the green light on. I have taken it completely apart since then looked at the circuit board and see no visible burnt solder marks or anything. Is there a way to troubleshoot these with an ohm meter/volt meter? Anyways, I have a Genesis with the Power Base Converter so I can still enjoy my SMS games, just wondering if I could get the old SMS to work for old time's sake.

Maxim Site Admin Joined: 19 Oct 1999 Posts: 14745 Location: London	Posted: Tue Mar 17, 2009 10:14 pm
	The AC might have killed it. The faint LED suggests it might have had problems anyway.

Rony_ket Joined: 09 May 2007 Posts: 137 Location: Sampa, Brazil	Posted: Tue Mar 17, 2009 10:23 pm
	Hmmm... looks that when you tried to put the N*S PSU on the SMS, you fried the 7805 (+5V) Voltage Regulator... This is a very very common and cheap component, even here in Brazil, and it looks like a MOSFET like transistor, easy to replace... It also looks like you have a problem with bad capacitors on the system, looks for some leaky or stuffed ones, and try looking at broken lines on the board... Some models, like Tec Toy SMS have a bad fenolite board, that the copper tracks lifts from the board, and gets very fragile, and usuallys breaks lines... If you have a Multimeter (or at least a voltmeter), you may try to check diodes from the power supply section, and also if's there +5V at all on some parts of the board to verify the problem

thatawesomeguy Joined: 25 Jul 2007 Posts: 731 Location: Melbourne, Australia	Posted: Wed Mar 18, 2009 8:10 am
	sst1226 wrote After that I went to Radio shack and purchased an adapter that matched the original, 1Milliamp, 9 volts, negative tip. The system will still not turn the green light on. I have taken it completely apart since then looked at the circuit board and see no visible burnt solder marks or anything. Is there a way to troubleshoot these with an ohm meter/volt meter? Err.. I assume you mean 9 volt 1 amp, as 1ma would be rediculously small. The original adaptor (at least for Austalia) is 9v 850mA.

sst1226 Joined: 06 Mar 2009 Posts: 5	Posted: Wed Mar 18, 2009 12:57 pm
sst1226 Joined: 06 Mar 2009 Posts: 5	Yes its 9 volt, 1amp. I'm pretty sure the bottom of my sega says 9 volt 850ma for required power but the adapter that came with the system says 9 volt, 1 amp

segamanxero Joined: 24 Nov 2007 Posts: 6 Location: South Boston	Posted: Thu Mar 19, 2009 6:35 pm
	Never use a NES AC adapter with anything but a NES... Even though the voltage info seems the same, I fried my first SEGA CD system when I was 8 with one... I am 22 now and will never make that mistake again with my precious Sega collection... there is something about that certain Ni****do AC adapter that is off, maybe the voltage and amperage info on it is wrong or slightly off? IDK On a related note, you can however use a SMS AC adapter with a Sega CD system (or model 1 genesis), I am doing that currently till I buy a Sega CD/Model 1 genesis AC adapter for it...

pepsiru1es92 Joined: 03 Apr 2009 Posts: 2	Posted: Fri Apr 03, 2009 2:26 am
pepsiru1es92 Joined: 03 Apr 2009 Posts: 2	segamanxero wrote Never use a NES AC adapter with anything but a NES... Even though the voltage info seems the same, I fried my first SEGA CD system when I was 8 with one... I am 22 now and will never make that mistake again with my precious Sega collection... there is something about that certain Ni****do AC adapter that is off, maybe the voltage and amperage info on it is wrong or slightly off? IDK On a related note, you can however use a SMS AC adapter with a Sega CD system (or model 1 genesis), I am doing that currently till I buy a Sega CD/Model 1 genesis AC adapter for it... The problem with the NES power cord is that it brings the voltage down to wherever it needs to be, but it keeps it in AC. Its brought into DC inside the console itself. if you use a genesis power adaptor on an nes, it just passes through the DC. imagine turing on and off your sms 60 times a second.

sst1226 Joined: 06 Mar 2009 Posts: 5	Posted: Fri Dec 16, 2016 10:17 pm
sst1226 Joined: 06 Mar 2009 Posts: 5	Rony_ket wrote Hmmm... looks that when you tried to put the N*S PSU on the SMS, you fried the 7805 (+5V) Voltage Regulator... This is a very very common and cheap component, even here in Brazil, and it looks like a MOSFET like transistor, easy to replace... It also looks like you have a problem with bad capacitors on the system, looks for some leaky or stuffed ones, and try looking at broken lines on the board... Some models, like Tec Toy SMS have a bad fenolite board, that the copper tracks lifts from the board, and gets very fragile, and usuallys breaks lines... If you have a Multimeter (or at least a voltmeter), you may try to check diodes from the power supply section, and also if's there +5V at all on some parts of the board to verify the problem Ordered the voltage regulator and from radio shack, soldered the new one in and I'm back up and running after having it sit around for over seven years. Plugged it in last night, played some Snail Maze, Astro Warrior, Hang-on and Space Harrier. It was great re living those childhood memories on a 60" flat screen. Thanks again!

Forums

View topic - Sega Master System Doesn't Work