Off frequency a bit....

[KB1TPX]

I was working LSB tonight, (Cobra 139XLR) talking with, Ontario, Toronto, Wisconsin, Michigan, etc.. Getting good reports for signal, but most commented that I sounded "off frequency". Well, it seems to me that everybody sounds "off frequency" until you tune them in better. Question is, if I am really off frequency, how do I fix that? My frequency counter doesn't work for sideband. Do I need to have a techie look at it?

 

[TonyV225]

Well I never touch my VFO's or Clarifiers I know Im on and along with the groups I alk to on a daily basis so if there would be a problem I would find out real quick.

This is also what most others do and if everyones on frequency and you come out and your the only one off well the writings on the wall so to speak. The only acception to this is if someone has a radio without a modified clarifier where they have full control of trans and recieve where there tied together / unlocked then to be nice a group may tune to that person but this usally only happens once or twice because as new people join in there frustrated and asking "why the hell are you all off frequency"?

You need to get the TX frequency allignment or adjustment number for your radio Ill look here I have almost all the cobras but Im willing to bet thats one I dont have I had a mint 139 at one time but left it stock so I never messed with my seetings in mine it was pretty close or close enough to not worry about it. If that board is simular to the 140, 142 146 I can most certainly help with all the setting you need for those aswell as the 148 and 2000 but I know its not the same as these last 2.

 

[KB1TPX]

Yeah, but what's odd is that I've talked to others in the past with no com, plaints. I was using an amp to cut through all the noise last night, I wonder if that was throwing it off for some reason.:headbang

 

[Highlander_821]

Sometimes other ops will tell you you are off frequency when the actual problem is distortion. I wonder if your amplifier is actually set up with the correct bias for SSB. If people say you are fine without the amp, but then say you are "off frequency" when you run the amp, then it is something with the amp either being class C, which won't properly amplify a SSB signal, or maybe the radio is overdriving the amp.

Then again, you might actually be off frequency.

 

[KB1TPX]

You could be right about the amp, because they say I have a strong signal, but sound muffled.
BTW, I can't tell one class from another so, here's the amp.:

 

[9C1Driver]

First question is did you have your clarifier unlocked? If it's stock then it will effect your receive only. So your radio could possibly be off frequency on the transmit side.

 

[Moleculo]

If it's really off frequency, you'll have to get the PLL aligned. The "muffled" sound may actually be a problem caused by your amp, as others have said. I'm not sure what those transistors are in that amp, but I imagine that it doesn't want a whole lot of drive. If your ALC or mic gain is turned up to where the signal is flat topping, it will sound horrible, especially when driven into an amp. The amp looks like it might be a class C amp, which will be an issue on SSB, also.

BTW, did anyone else notice the low pass filter in the output of that amp? That's something you don't see in CB amps very often.

 

[KB1TPX]

If it's really off frequency, you'll have to get the PLL aligned. The "muffled" sound may actually be a problem caused by your amp, as others have said. I'm not sure what those transistors are in that amp, but I imagine that it doesn't want a whole lot of drive. If your ALC or mic gain is turned up to where the signal is flat topping, it will sound horrible, especially when driven into an amp. The amp looks like it might be a class C amp, which will be an issue on SSB, also.

BTW, did anyone else notice the low pass filter in the output of that amp? That's something you don't see in CB amps very often.

I did have the mic gain turned up high and the gain on the Turner +3B as well. I'll try it again tomorrow with everything turned down, right now that amp is in the mobile, I only bring it in the house once in a while. BTW, I used to have a car battery in the house that I ran it off of, but I did away with it when I noticed it leaking a little. Now I run it off of a power supply, which probably doesn't produce enough ampereage. I think I should just stay barefoot until I get a 20A power supply.