I have a WHCA Secret Service surplus radio that I need to change the bandsplit on. RSS currently reports the radio as being a 157-174 split. I want to utilize this radio on the Amateur 2 meter band (144-148). The rx receives fairly well, but not as good as it should. In the 155 Mhz range, it seems to be up to snuff. But, in the 146 Mhz range, there is an undesireable noise that is annoying. It does not cover up the desired signal completely - it is only at about 5%-10%. The best description that I can use is a buzzing, hash noise, or low pitched tone. If I saturate the rx with a nearby transmssion, the noise is not in there. But, while monitoring repeaters in my area, it is always there. If need be, I can make a recording. I'm hoping that changing the bandsplit will revive the Saber performance to normal. I have never transmitted with this radio yet. It did not come with an antenna. I should have one tomorrow or the next day that I ordered from Waltel. Then, I can report the tx side of it. The model # is H43TUK5170CN and has DES.
Are the modules that I need to replace readily available at a reasonable cost? From what I have read here in the forum; the modules that I need to replace are the Synthesizer, Receiver, Filter/Detector/Switch, and PA. And possibly a 2 Pole and a 5 Pole module(s). Is this correct?
If the modules are readily available, I am going to purchase a few tools to disassemble the radio and swap out the modules. I really like the radio; but I want it to perform as it was designed. I am a novice at this game, so any help you guys will give me will be greatly appreciated.
Victor, KB5AKO
[email protected]
Systems Saber 3 VHF Changing Sub Bandsplit
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Systems Saber 3 VHF Changing Sub Bandsplit
OK, to get a 136 - 150.8 split,
It looks like I need to replace the:
Synthesizer - U-300 - with NLD8201X - X= A OR B
Filter / Detector / Switch - U-203 - with NFD6131A
2 Pole Filter - U-1 - with NFD6111A
5 Pole Filter - U-2 - with NFD6091A
PA - U-202 - with NLD8121A
(I'm not positive on the chip numbers).
Then after a re-alignment, all is well.
Am I missing anything? Are all my numbers good?
Victor, KB5AKO
[email protected]
It looks like I need to replace the:
Synthesizer - U-300 - with NLD8201X - X= A OR B
Filter / Detector / Switch - U-203 - with NFD6131A
2 Pole Filter - U-1 - with NFD6111A
5 Pole Filter - U-2 - with NFD6091A
PA - U-202 - with NLD8121A
(I'm not positive on the chip numbers).
Then after a re-alignment, all is well.
Am I missing anything? Are all my numbers good?
Victor, KB5AKO
[email protected]
You have the porper numbers listed, those are the correct ones for the band split you need to get down to the 2 M range.
As we talked about on the phone, the swap is simple, even an RSS alignment will get you so close to the ballpark, most will never notice any slight misalignment.
If you are more concerned about splatter, then by all means have it sericed with a service monitor to make sure.
As we talked about on the phone, the swap is simple, even an RSS alignment will get you so close to the ballpark, most will never notice any slight misalignment.
If you are more concerned about splatter, then by all means have it sericed with a service monitor to make sure.