Karl's Link Radio page
This page is all about modifying radio equipment for a better way to pass signals for long-distance links and other uses, starting with the COR/Audio board.
Several versions were designed however, not produced. Your main starting point will be version 5.3.
My COR board project:
COR/Audio board Ver. 5.3 Updated 7/6/03, 3/29/04, 8/27/05, 6-25-06, 4-10-09
COR/Audio board Ver. 5.4 For Downlinks
COR/Audio board Ver. 5.5 For Uplinks only
COR/Audio board Ver. 6.0 Designed for a conventional repeater (single site).(alpha-not produced)
COR/Audio board Ver. 6.1 Designed only for mitrek, in place of PL deck.(beta-in prototype stage)
COR/Audio board Ver. 6.2 Designed only for mitrek, in place of PL deck.(beta-in prototype stage)
Version 6.3-for the Mitrek radio PDF
COR/Audio board Ver. 7.0 Designed only for mitrek and micor link radios.(alpha-not produced)
COR/Audio board Ver. 7.1 Designed only for mitrek, possibly in place of PL deck.(alpha-not produced)
COR/Audio board Ver. 7.2 Designed only for mitrek, in place of PL deck.(alpha-not produced)
COR/Audio board Ver. 7.3 Designed only for mitrek, in place of PL deck.(alpha-not produced)
Version Chart Quick comparison charge for different versions over the years.
Motorola Mitrek area - Lot's of information
Most of these documents are in PDF for easy viewing with any O/S. Also, some of them are large in size:
Mitrek conversion to Repeater or link in PDF
Details on the antenna conections in PDF
Frequency options in PDF
Details on the casting in PDF
Operation manual in PDF
Motorola Micor area - Lot's of information
Micor transmitter for repeater service in PDF
Suppliment for above in PDF
Micor receiver converstion in PDF
Micor squelch theory in PDF
GE for repeater operation in PDF
Audio Standards Flat or conventional audio and level standards
Direct F.M. a Midland 13-509, or most any transmitter
Midland 13-509 Full story on F.M. and repeater conversions for 1 1/4 meters
Wilson 1 1/4 meter radio For the model T2202SM HT.
MX-350 Portable Radio for links Used in some SRG 20 repeater links
Johnson PPL6060 UHF radio notes Improving transmitter frequency stability
Fan assembly to cool a transmitter Used in some SRG 20 repeater equipment
GE Mastr II repeater interfacing to a link in PDF
SRG Library Tech documents
A note about the documents; recently they are starting to be converted to PDF for a couple reasons; this solves the issue with html pages (with images) being displayed on various browsers (with other variables) and generally is smaller in file size. This is especially true for a MS-Word document (with images) compared to the size of the same document in PDF. PDFs are easy to download to your PC for later viewing.
Note: Many of these projects are in the R-n-D stage, therefore, are subject to change and improvement without notice.
They are intended to get the experienced builder in the right direction and not necessarily for the beginner.
Tip: Some are PDF's therefore, to save time you can right click on the link and "save as" to your PC for local (and faster) viewing.