Weather Station

These are pdf's of manuals and other information that I have collected, assembled, or wrote for my own use. 

There is no fee, restriction, or condition for downloading any of the information contained here.  It is provided in the best spirit of the Ham Radio Tradition: helping others.  It is provided for those who have a thirst for information or who may be stuck trying to fix a boatanchor and don't want to pay some knucklehead $47.00 for a pdf copy of a scanned 40-year old manual that originally sold for $2.00.


If you have any objections, please don't download.


All of these manuals have also been uploaded to and I encourage you to upload any manuals you may have that are not currently on  Eric Hansen (OZ1TF) is the moderator.   



Support The Consumer's Right To Repair Equipment




HP-23a Assembly Manual

HP-23 Service Bulletin

HP-23a Schematic Diagram

IO-4235 Schematic Diagrams

IO-4235 Operation Manual



MFJ-259 Calibration Instructions



Precision 600-Series Tube Test Data

Precision 612 & 614 General Operating Instructions

Precision 612 & 614 Schematic Diagram

Precision 612 Refurbishing & Calibration