JT1000 making a knocking sound on transmit

[taylorbrinton]

I just picked up a JT1000 and when I transmit it has a knocking sound fairly fast and constant. We have tried to change batteries and Antenna but can't seem to make it go away. Does anyone have any ideas as to how to fix it or have you heard of this problem?

Thanks,

Please let me know what other detail you need to know to be able to help.

[RadioSouth]

If it's UHF try searching under Jedi Microphonics. Hopefully that's it.

[taylorbrinton]

It is not UHF it is a VHF radio and reading about what you posted is not what I am hearing. Sorry. This is more like an electronic knocking sound. Like a metronome sound.

[com501]

Check the radio internally for a high level after market encryption board. Sounds like someone didn't disable it properly. Many of these radios had those installed, most typically a Transcrypt version.

[Karfield]

I will agree with com501, lets hope however that you have a zif version of the board. If you have one that is hard wired it'll be difficult to get the controller back to working status. Also, if you do have a standard push in type of board make sure you take out the option board in RSS so that you don't loose all audio. From main menu F4, F3, F5.

[taylorbrinton]

Thank you, I don't know enough about these radios to know what to look for.

Is there a good resource for looking up what you are talking about???

Thanks,

Taylor

[Karfield]

There are 3 manuals that if you can get ahold of they'd have all the info you would need as far as the "encryption" board that could be in the radio.

1. The RSS manual for programming etc
2. The radio manual itself which contains all the theory and the schematics. For jedi that contained both the basic and detailed manuals.
3. The AVS manual which came with every AVS board. It's a pretty thin manual and I've only skimmed it once or twice. Wasn't really my game to know too much about it.

After that, Batlabs is your best bet for info. So if you have RSS for HT1000/Visar just load up the codeplug check the screen I told you about and see if it's installed. Otherwise you'll need to head out to your local (or not so local) MSS and have them read it for you.

You can also open it up and see if there is a board in there. DO NOT remove it as you will no longer have any audio once you do. Once the radio is reprogrammed you can remove the board and you should not have any "problems" from that pesky addon board anymore.

[The Pager Geek]

Out of curiosity:
Does it happen on all channels?
Does it make a difference between transmitting DPL, PL or CSQ?

tpg

[Will]

Make sure you have the correct antenna for the transmit frequency. Incorrect frequency range antennas can cause RF feedback into the radio causing all sorts of problems.

Bad antenna.
Loose antenna fitting in the radio
Poor contact from the RF board to the antenna jack.

[taylorbrinton]

Tried different antenna and made sure it was the right antenna and still have the issue.

I am going to do what the others have said this weekend and hopefully I will be able to get it fixed.

Thanks everyone, I will keep you posted as to my results.

Thanks