In a large bowl whisk eggs and 1 1/2 cups sugar together until light and fluffy. Set aside.
In a large medium sauce pan, over medium heat, heat the milk and cream together, stirring occasionally until the temperature reaches 140 degrees. Remove from the heat.
While whisking the egg sugar mix, very slowly add 1/3 of the hot cream/milk mix to the egg/sugar mix. Whisk until blended. Now pour the rest of the cream/milk mix in, and whisk to combine.
Pour the custard back into the sauce pan, and heat over medium heat until the mix reaches 175 degrees. (this will kill any bacteria the eggs may have)
Once the temp has been reached, pour into a large bowl, and place in the fridge for two to three hours.
While the custard is chilling, toss the blueberries, strawberries, lemon juice, and sugar into a bowl. I went with 1/2 cup, but you can add up to 3/4 cup sugar. Using a potato masher, or a large beater from your hand held mixer, mash the blueberries and strawberries, and mix into the sugar and lemon juice. Place in the fridge until you are ready to pour the ice cream into the ice cream maker.
After your custard has chilled, remove it and the berry mix from the fridge. Pour the berry mixture into the custard, and stir to combine. Using the manufacturers instructions, pour the ice cream into your ice cream maker, and allow to start freezing. Freeze in the freezer until hard and scoopable!