Replacement power supply unit

From The Dragon Archive

It is relatively easy to build a replacement power supply for a Dragon 32 or 64 if the original stops working. The external power supply is basically a transformer connected to a 9 pin D-sub connector. The diagram shows how the transformer is wired to the 9 pin D-sub connector. D-subs always have numbers printed on them so it is impossible to get the wiring wrong.

The trick is to find a suitable transformer. The colour codes specified in the diagram are for a transformer purchased from ELFA, a relatively big vendor of electronics components and equipment in Scandinavia. The table below lists part numbers from the ELFA catalogue.

Count Description ELFA part number
1 Toroid transformer 55 VA, 8,5 VAC + 2 x 14,4 VAC 56-109-10
1 Female D-sub 9 way 44-160-54
1 D-sub plastic hood 44-085-06

Dragon power supply schematics.png