I just noticed that the Polish guy, making the 3GHz prescalers for the Agilent 53131/132's. Got an excellent review here (for the pcb etc) https://www.youtube.com/watch?v=21_9Dspzu_w Now he's made a 3Ghz prescalerboard for the PM6680/85. So i had to get one , *bay: 111612684288 Will let you know the outcome. CFO