Spectrum Computing

I was torn between posting this in Hardware or Other Retro. I went for other retro.

Two of my cursor key switches have failed on my Sony MSX so thought I would replace them. I measured the size, and ordered these. Would any hardware or electronics experts out there let me know if they look the right type?

Also, do they need to go in a certain way round, and any tips for removing the old ones. There is no space for cutters.

Thanks

https://www.ebay.co.uk/itm/111726375227



Thanks in advance

Probably yes, as long as you get the exact same size.

Tactile push button switches (nearly all are SPST) come in a wide range of sizes, including physical size of the case/housing, button size and height. Also the pitch between the pins varies.

They may fit one of four ways, but electrically only work two ways round. Although they have four legs/pins, two are internally connected to one switch contact, the other two being connected to the other switch contact.

Unless stated in the listing or datasheet, you will need a multimeter or continuity tester to work it out (and often it’s quicker than trying to find it in the datasheet).

The electronic suppliers also carry a wide range of these.

As they normally have legs/pins that clip the switch to the board, they can be a bit tricky to remove. Remove as much solder as possible, then use electronic flat/flush wire cutters to cut the legs/pins as close as possible flush to the board. Reheat the joint and very carefully prise up the switch on the component side of the board, then do the next leg/pin.

Oh, and if you have enough spares, best to renew all four.

Mark

Thanks [mention]1024MAK[/mention]!

[mention]1024MAK[/mention],

Just to let you know it worked!

Thanks for your help Mark. First soldering in 30 years. Just got to tackle that RAM replacement on the runner key Spectrum that you also helped me with.

Peter