LED Display

A while back one of my roommates bought 2 LED displays as part of a project idea. The signs kind of fell on the backburner as other things came up, but I thought that I could start playing with one of them since it shouldn’t need much work to get it operational again. The display is an Alpha 210A, and is missing both its power supply and controller. Normally a missing power supply wouldn’t be a problem, however this sign uses 7.5VAC. Finding a transformer with a secondary rating of 7.5VAC proved to be rather difficult, but I finally managed to find a place that had something usable. Herbach & Rademan carry a transformer that provides 7.5VAC at 1.5 amps, so I need 2 of them, as the sign is rated at 2 amps, but for $3.95 a piece I can’t complain. They do have a $15 minimum order but they had other items that I needed anyway. Their site does not have a secure checkout, so you might want to consider calling or faxing your order.

The next issue, of course, is the programming controller. According to the Alpha website, the displays use either RS-232 or RS-485 to communicate with the controller. I’m not sure which standard my sign uses, but if its RS-232 conectivity will be easy. RS-485 shouldn’t be a problem but will require an adapter. I’ll look for the specifics of the communications once the transformers come in and I can verify that the sign actually works.

1 comment

  1. I also have qty 2 of the alpha 210c signs, the OEM Adaptive Systems no longer stocks the power supplies, but the user manuals are available online.

    The original power supply outputs 7.5VAC at 4.0 amps. The minimum power requirement, according to my
    variac, is 7.5vac at 2.5amps.

    It turns out the signs can be somewhat programmed by using the DIN-5 keyboard port.

    I hope this helps…

    Regards, Steve
    Cincinnati, Ohio

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