Display for Narco MK-12D / D+ P/N 50401-0001


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Current Price: 319.00 USD

I have purchased the end of the factory production overrun stock. I only have a few, which will be released one at a time. The price has gone up, as I pick these up from the factory in person to assure good handling that they require, and that cost is amortized only among a few parts.

New, from the same US-based OEM vendor that supplied Narco when they were still in business. Every avionics-related item I sell is in the spirit of reducing costs for pilots like myself. I've helped over 1000 MK12D owners get their displays working again. I'm an electrical engineer and Narco Mk12D+ owner too!

If your Narco MK 12D-series radio has malfunctioning digits with age or is getting dim, this is the part that you may need for repair. Hard to find, and otherwise very expensive! Replacement with common hand tools takes about 20 minutes, with the superior detailed pictorial instructions I provide. I even furnish the uncommon small tool and spare setscrews!

Each order contains:

1 OEM display, Narco P/N 50401-0001, shipped in anti-static materials and box with ample padding to avoid dislodging internal liquid mercury in transit

Instructions with pictures for inspection and installation (sent as PDF by email after shipment--look for address on your packing slip)

1 each hex and spline (Bristol) wrench for knob setscrew removal

4 spare setscrews for knobs, in case you lose or strip any
Note that not all Narco display malfunctions are due to the display component itself, such as sudden blackouts, which may also trace back to the high voltage power supply used to run the display. Segments persistently stuck on or off across all digits on either the NAV or COM sides, may trace back to the high voltage display driver components or an array of diodes used to "quench" the segments. Complete gibberish on one side of the radio, which varies with frequency tuning, is almost always caused by a defective 8884A BCD decoder/driver chip. A typical failure caused by the display will exhibit gradual degradation in brightness until some digits or segments are left working sometimes but not others or flickering, improving after the radio gets warm, and the degradation is more pronounced in dim light or by covering the front panel photocell, when intensity is automatically turned down. A display failure will likely be uniform across the NAV and COM sides, rather just on one side while the other side remains bright and functional.

I have a history of working with potential buyers to assure their problem is likely due to the display, and work with buyers after the sale in case their radio has other display-related issues. Out mutual goal is to get your radio working again! If you have a question, history of your radio and pictures are valuable in helping me to help you.

If you do not choose to replace the display yourself, make sure that you choose an FAA-approved repair shop to do so, in order to maintain the radio's airworthiness, and to make sure your radio and the display are handled properly.

Due to the nature of this component and FAA requirements, no refunds will be issued for displays that have been installed, or where the glass or pins are in any way bent or broken. Verify your high voltage and failure symptoms first! I encourage dialog and furnishing of pictures showing the display in the radio.

Displays will be shipped in anti-static material with ample packaging, in a box, to prevent damage and internal displacement of mercury, which will drastically shorten the display's life. Shipping is via USPS Priority or Express in the US only. This part CANNOT be shipped internationally and international orders will be cancelled.


Display for Narco MK-12D / D+ P/N 50401-0001  Display for Narco MK-12D / D+ P/N 50401-0001


Click here to purchase or contact the seller of this item on eBay