Hi I'm trying to adapt a Lenovo IBM Thinkpad 20v 90w power brick to run a TPA 3116 Amp. To my knowledge the Lenovo has a round tip 7.9 x 5.5 mm jack. The amp power in is 5.5 x 2.1 mm. I've spent hours looking for a suitable adapter. Has anybody tried this on a Lenova? Can anybody help me out here please?
Without considering the electrical aspects.....
sometimes it is easier to cut and splice with the original connector , than find a suitable adapter.
I did this with a Dell laptop power brick.
sometimes it is easier to cut and splice with the original connector , than find a suitable adapter.
I did this with a Dell laptop power brick.
Get a pair of matching male female plug/sockets, which can't be reversed, and use those..
Cut off the brick plug about 2 inches away, so that can be reused if needed.
And put a big diode on the amp positive input as a protection against reverse polarity. Or a bridge rectifier, then it will better protection.
This use of a laptop brick seems to have been done earlier, a good thing, instead of scrapping a good supply.
Do check it is working properly before use.
Cut off the brick plug about 2 inches away, so that can be reused if needed.
And put a big diode on the amp positive input as a protection against reverse polarity. Or a bridge rectifier, then it will better protection.
This use of a laptop brick seems to have been done earlier, a good thing, instead of scrapping a good supply.
Do check it is working properly before use.
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You can probably buy a replacement Lenovo jack off Ebay but would need a PCB to mount it to.
Easier to buy a plug to match your amp and cut the Lenovo cable as previous posters have stated.
Heatshrink over the plug body & cable makes a really secure boot to prevent cable pull out or kinking.
Easier to buy a plug to match your amp and cut the Lenovo cable as previous posters have stated.
Heatshrink over the plug body & cable makes a really secure boot to prevent cable pull out or kinking.
I spliced the cable on the power supply....inside, both posive and negative cables are multi-threaded. Are all power bricks made like this?
You mean multiple strands?
If you can solder them, well and good.
Not really needed for DC, and I do not expect them to be metallised plastic thread.
Possibly to make them more flexible...
Insulating tape degrades over time.
Use heat shrink over the joints, or screw type connectors, insulating tape over that.
If you can solder them, well and good.
Not really needed for DC, and I do not expect them to be metallised plastic thread.
Possibly to make them more flexible...
Insulating tape degrades over time.
Use heat shrink over the joints, or screw type connectors, insulating tape over that.
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....it makes things more difficult, and I still need the Notebook occasionally so cutting the cable......?
Find another brick in scrap..goes for pennies.
Or keep two female connectors, one for amp and one for notebook.
Or keep two female connectors, one for amp and one for notebook.
