Uniden AX 144 SSB/AM No Audio

[Willo]

Hi ppl, I have a Uniden AX144,Board N# PC-833AE, PLL Chip D2824c.
I turn the radio on after years of storage and it has no RX audio.It is TXing fine full power and output audio.It is RXing a signal but no audio is coming out.
What I have dont so far: Check speaker, no change. Plugged in external spk, no change.Replaced Audio IC upC1182H.No change.....Can someone help me...? where do I go from here???

Thanks Glenn

[Willo]

Update: It has audio out in PA mode but not real clear...it could be the ext spk i'm using too..but It does have audio in PA.

Glenn

[Willo]

The Uniden AX144 is the same as the AR144 if this helps....The Audio chip get warm when TX'ing.... Any help out there please...

Thanks Glenn

[Rick]

Is the S/RF meter showing an incoming signal? If the answer is yes then check to see if the volume control is open circuit, you can do this by connect a wire form the centre connection of the volume control to the outer connection, this maybe very loud but it will tell you if the volume control is the fault.

Your quote
The Uniden AX144 is the same as the AR144 if this helps....The Audio chip get warm when TX'ing.... Any help out there please...
End quote

This should not happen as the audio chip is only used in RX and PA mode. This maybe a red herring, trying leaving the radio switch on in RX mode for about 5 to 10 minutes and check the chip it should be warm.

You may find that one or all the electrolytic cap around the audio chip have dry out due to the radio being stored. C132, C134, C135, C136 and C142.

You have check the speaker yes?

Let us know how you get on.

Rick.

[Willo]

Hi rick, sorry for the delay in replying I have check the speaker its ok.I have plugged in an ext speaker as well.....I will try what you said..and get back to you once again thanks for your help..Glenn

[Willo]

Let the radio idle for 10 min the audio chip is just warm.....I jumped the vol pot and didn't get volume..only scratchy static noise...when I turn the vol up & down I get the scrathy noise out of the speaker. I will try replacing the electro's around the Audio IC....

[Rick]

Is the S/RF meter showing an incoming signal?

Have you tried a PA test?

Rick.

[Willo]

I have tried PA and have got voice out in PA mode but it is distorted. Tested the PA speaker with another radio on PA, crystal clear audio out.

[Rick]

Is the S/RF meter showing any incoming signal?

Is the Squelch working?

Rick.

[Willo]

G'day Rick ....When I turn squelch knob up and down I can here the pop sound like normal. If I put my ear to the speaker on the radio I can faintly here sound....white noise.

[Rick]

I see you have still not answered the question below
Is the S/RF meter showing any incoming signal?

Can you do some voltage check on transistors TR10, TR11, TR15, TR16, TR17, TR31, TR32 and TR33 in RX and TX mode. It maybe TR31 is open circuit.

Rick.

[Willo]

Sorry mate been on holidays for easter....Yes the S/meter does move when RX a signal and moves when TX as well. I'll msg you back with the TR voltages......Thanks Rick

[RW023]

how do u tune down the singal meter inside the radio for am only whats the vr for singal for a ax144 26mhz radio

[Bundy]

Check pin 3 IC4 (uPC1182/uPC1242) Look for dry solder joint, have had this fault in 2 AX144z