| Author |
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Therealporkchop
| | Posted on Sunday, May 25, 2003 - 12:03 am: | 
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Does anyone know how to stop that squeal you get in your talkback after you peak/tune this radio? The fix listed on Galaxy's site stinks, it isn't working on my radio. I get a buzz and popping. Can anyone help with this. Talkback isn't really important, but it would be nice if it worked. I hate to cut the wire to it....
Thanks
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Tech671
| | Posted on Sunday, May 25, 2003 - 5:38 am: |
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There's a fix for it but I can't explain it through the keyboard. Drop me a mail and we'll work it out. |
Kc0gxz
| | Posted on Tuesday, May 27, 2003 - 2:59 am: |
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Therealporkchop...
If you are experimenting feedback problems from your talkback, try turning your power mic down if you are using one. And make sure that your speaker is not too close to your radio. If you are using the radio for mobile use, get a good noise cancelling mic. It will reduce most of your feedback as long as your speaker is far enough away from your radio.
I had a simular problem like this with a radio that a customer brought to me and i tried this little "fix" that someone sent to me. It was a Galaxy 66 and it worked on that one.
Talkback can become distorted when these radios have been "peaked," and there isn't much in the way of a cure for it that I know of. The talkback just amplifies what goes to the RF section.
Try this. Add a 470k ohm resistor from junction of C154/R207 to the junction of C187/R235 on the solder side of the board. This will also give you clean talkback on SSB and FM. If that doesn't work, try different values of resistance to get the amount of volume you want. The higher the resistance, the quieter the talkback will be and of course the lower the resistance the louder the talkback will be.
That just might remedy your feedback problem but it doesn't do much for any distortion that you may have. But then, you never did say anything about a distortion problem. Oh well. Good luck with it. I hope this may have been some help to you. Email me if you would like to see a picture of what this modification looks like.
kc0gxz@aol.com
Jeff, kc0gxz. |
307
| | Posted on Tuesday, May 27, 2003 - 12:24 pm: |
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Remove the TOP cover. Locate the 4 screws (one on each corner of the main board). Tighten them all down secure. This should eliminate the squeal.
307 |
Therealporkchop
| | Posted on Saturday, May 31, 2003 - 11:32 pm: |
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Thanks for the answers, but I don't get the thing about the screws. What does that have to do with it? |
307
| | Posted on Sunday, June 01, 2003 - 7:48 pm: |
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When the capacitor coupling looses ground , i.e. the chassis to the case by loose screws , The talkback goes ballistic and will squeal like a dog...I have seen at least 70% of ALL the galaxy radios I have worked on for "squeal" , has had those screws loose...This MAY NOT be your problem , however , it is worth the shot. The popping is the discharge of the feedback circuit in the audio amp because the talkback mod destroys the working part of that circuit (removing the cap , if this is your case for louder talkback) , by driving it harder and then picking off of it for the speaker as well as audio for TX.
307 |
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