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External squelch control for Motorola radios

Posted: Fri Dec 12, 2003 12:28 pm
by kilowna
Does anybody have any information on an external squelch control for Motorola M1225, CDM750 models? I used to be able to do this with Vertex way back when they stopped using external squelch. Does anybody know why external squelch pots are not used? :cry:

Posted: Fri Dec 12, 2003 12:44 pm
by KG6EAQ
The operators.

Posted: Fri Dec 12, 2003 1:33 pm
by CTAMontrose
KG6EAQ wrote:The operators.
hahaha that has to qualify as the answer of the day

Its funny, because its true.

External squelch control...

Posted: Fri Dec 12, 2003 2:24 pm
by Tom in D.C.
I own an old MT500 which was once owned and used by an airline and it's an omni with no external squelch, though the pot can be found and adjusted inside the radio.

Absolutely no reason for doing this except to keep the help from messing with the squelch setting, IMHO.

Posted: Fri Dec 12, 2003 4:11 pm
by ExKa|iBuR
There's not really any reason to need to adjust the squelch...

As the saying goes with that Ronco grill "Just set it...and forget it!"

-M

Posted: Fri Dec 12, 2003 5:39 pm
by Nand
The function of the squelch in a VHF or UHF radio is to kill mostly its own internally generated noise when no RX signal is present. This is the noise you hear when no antenna is connected and the squelch is open. In older radios this noise was less constant because of temperature and voltage variations in both the RF circuits and the squelch circuit itself. The front panel squelch control allowed compensating for these variations.

Modern radios are far less sensitive to these variations and consequently do not need an external squelch control any longer. Models like the CDM, M1225, P1225 and the Warris series do have an optional setting in the RSS that allows a button to be programmed for tight or loose squelch if needed to eliminate light interference when only carrier squelch without PL is used.

Nand.