How to build a custom "Saber only" RTX-4005B
Posted: Thu Mar 04, 2004 12:54 am
I am only going to be servicing the Saber and Systems here and I am thinking of building my own RTX-4005B to save a few dollars (yeah another Ham!) and have come up with a few questions.
Looking at the RTX-4005B and the Service Cable Schematics:
http://www.batlabs.com/images/sabsvc.gif
http://www.batlabs.com/images/rtx4005.gif
and also figuring out what is exactly used on the regular Saber and Systems Saber I see alot of switch positions and connections (MX-MT) that could maybe be left out if one was to custom build their own "Saber only" RTX-4005B.
I see the Mic Input needs a basic resistive padding circuit and the PTT switch is very basic.
Some of the things I see that could maybe be left out are:
- MT B+ 12 Vdc
- MT PL
- Disc (MX300 only)
- Vol Cont
I think the audio PA point is used on the Systems Saber for signaling(trunking) on the alignment and I may need to leave that in.
The last part is the various switch positions used in connection with the speaker output (and that T1 feeding J7 Pin 12?). Are they all necessary? I am guessing these provide a various loads for distortion measurements.
Not having a RTX-4005B or ever having used one this has me a bit confused in what is commonly used (switches connect points etc) and when so any info/documentation would be appreciated.
Thanks,
Eddie
N4UMJ
Looking at the RTX-4005B and the Service Cable Schematics:
http://www.batlabs.com/images/sabsvc.gif
http://www.batlabs.com/images/rtx4005.gif
and also figuring out what is exactly used on the regular Saber and Systems Saber I see alot of switch positions and connections (MX-MT) that could maybe be left out if one was to custom build their own "Saber only" RTX-4005B.
I see the Mic Input needs a basic resistive padding circuit and the PTT switch is very basic.
Some of the things I see that could maybe be left out are:
- MT B+ 12 Vdc
- MT PL
- Disc (MX300 only)
- Vol Cont
I think the audio PA point is used on the Systems Saber for signaling(trunking) on the alignment and I may need to leave that in.
The last part is the various switch positions used in connection with the speaker output (and that T1 feeding J7 Pin 12?). Are they all necessary? I am guessing these provide a various loads for distortion measurements.
Not having a RTX-4005B or ever having used one this has me a bit confused in what is commonly used (switches connect points etc) and when so any info/documentation would be appreciated.
Thanks,
Eddie
N4UMJ