decode.js

const Iconv = require ("iconv").Iconv;
const request = require ("request");

const urlTestFeed = "https://www.presseportal.de/rss/dienststelle_110972.rss2";

request (urlTestFeed, function (err, response, theString) {
	var iconv = new Iconv ("ISO-8859-1", "UTF-8");
	theString = iconv.convert (theString.toString ()).toString ();
	console.log (theString);
	});

package.json

{
	"name": "test",
	"description": "A test app to help get decoding working in feed reader.",
	"author": "Dave Winer <dave@smallpicture.com>",
	"version": "0.4.0",
	"dependencies" : {
		"request": "*",
		"iconv": "*"
		}, 
	"license": "MIT",
	"engines": {
		"node": "*"
		}
	}