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Author Topic: tech/elect. problem  (Read 1751 times)

Nella F.

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tech/elect. problem
« on: June 18, 2014, 1939 UTC »
Got a problem with the electronic innards of my Pro-94 squelch (& have since buying new in 2001).
When I adjust the squelch knob for normal traffic there is an 1/8 of a second "hiss" at the end of every transmission. This "hiss" is what you normally hear when the squelch is turned fully counterclockwise. Adjusting the squelch further clockwise makes No difference (besides reducing normal traffic reception).
Is there some sort of an adjustment that can be done with a screwdriver to correct the problem (flathead or "Philips") & not a soldering iron?  Thanks in advance.  
                                           I can see you  8) but you can't tell if I'm looking at you.


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Re: tech/elect. problem
« Reply #1 on: June 19, 2014, 2247 UTC »
I doubt there is an easy adjustment for that. This squelch control apparently has some "delay" built into it so that the radio will hold on to a signal that may be of variable strength (Ie Fading up and down).

If someone could look at the circuit, they might be able to adjust a R or C value some where to make it react faster....but that requires a soldering iron.

Nella F.

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Re: tech/elect. problem
« Reply #2 on: June 19, 2014, 2322 UTC »
Thanks. I'll probably tolerate it. I was tolerating the battery saving function... could hear an annoying "click" every couple seconds then a sudden & rare flash of thought occurred: maybe I can cancel that function like cancelling that annoying "beep". Sure enough turn off scanner, press & hold "priority" button & turn back on & presto no click. Very annoying when trying to read. Can't have any distractions these days. Glad I saved the instructions.                
                                      "Here's L  8) king at you, kid."
                                                  "Old  :( now"
« Last Edit: June 20, 2014, 2331 UTC by Nella F. »

Offline redhat

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Re: tech/elect. problem
« Reply #3 on: June 20, 2014, 1158 UTC »
Yeah, unfortunately squelch tail has been with us a long time.  In the interest of being a pest, real radios like Motorola, GE, et all, support something called reverse PL.  When the person transmitting releases PTT, the radio reverses or shifts the phase of the PL tone, which tells the radio to close its squelch.  Its been around for a very long time, yet to my knowledge, none of the ham rigs out there have it, which I think is stupid.


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WinRadio Excalibur/305 w/ a chi-town resonant loop, Kenwood KDC-U356 for mobile listening.
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Nella F.

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Re: tech/elect. problem
« Reply #4 on: June 20, 2014, 2334 UTC »
Don't have the problem with my Pro-43. Just a thought.