Saber III - hum on TX carrier - NOT PL?

[g8tzl2004]

I have a Saber III which has a hum on the TX carrier. It sounds a bit like a loud PL tone.

When I press down around the edges of the keypad , especially around the left hand edge of the keypad area the hum disappears and I get good audio.

Any ideas as to the cause? Maybe its a poor internal mic connection or something?

Hope someone can help.

thanks

[Will]

Internal front shield not making contact, Wrong antenna.

[g8tzl2004]

Thanks Will.

I will check out the front shield.

The antenna is correct but when I TX with my hand grabbing the antenna the noise significantly reduces - I guess I'm stopping the RF radiating back into the radio via the loose front shield?

[mike m]

Is this a UHF radio?

I vaguely remember a rf shielding kit that moto had for some UHF models, I have one with the rf shield mod/kit but even with this addition the radio at times does the same thing that you describe.

[g8tzl2004]

Yes, it s a UHF radio.

I have a couple of identical radios and they are OK. I will check to see if they have the same year of manufacture.

I will check the front shield. If that does not work I might lower the power output!!

[g8tzl2004]

I cleaned up the front shield and the noise has gone!!!

The front shield is a very poor fit. It did not really click into place. I was thinking that I might bend up the sides of the shield where the tabs were located but I did not bother. I just cleaned up the sides where you could see dirt. That seemed to do the trick.

I quickly checked out my other 2 UHF Sabers and one only puts out around 50-100mW and the other is 8KHz off frequency. I guess one has a faulty PA and the other has a faulty ref crystal...but it might be dirty contacts or something. I guess I will do a separate post for these other faults.