Adjusting SSB/AM power on Cobra148/GrantXL question...

[doffo]

Hello,

I am wanting to adjust my deadkey on my Cobra 148 and my Uniden Grant XL. They are the side mic models. After reading some on the radios I believe VR10 adjusts AM power and VR11 is SSB power.

My question is, how or is there a proper procedure to tune these? Do you have the mic gain all the way down or all the way up?

Also, when you adjust SSB power, is there such thing as a deadkey for it? Reason I ask is because I thought it actually has no power till you start to talk into the mic.

Any help would be appreciated. Thanks!

 

[1FatBoy]

This is best left done to someone who has the knowledge and the right equipment. On the other hand there is no way to learn unless you dive in and do it.
The alignment procedures can be found on the cbtricks website.
Specifically this file Pages 48-63 of the service manual
Best advice : Don't turn anything unless your sure!

 

[Robb]

First of all, if you don't mind risking the radio you have and want to make adjustments inside; then be prepared to make mistakes. Some adjustments you can take back; and others might cost you for parts and a guy to repair it.

Having said that, the quality of the meter is important too. Most meters should be fairly accurate for setting dead key watts; they are usually off by about +/- 1/4 to 1/2 watt. Just keep that in mind.

Yes; VR10 is for setting the dead key watts on AM.

SSB does not have a carrier. At least, if it does - it has a problem with the balanced modulator IC or it is out of adjustment. SSB is modulation drvien power; it does not use and need a carrier.

 

[doffo]

Thanks for the help so far.

So since I would have to set it with the mic gain all the way down.. should I keep it all the way down when I go to use it on the KL-203P amp?

 

[1FatBoy]

No, the reason why you set your carrier (dead key) with the mic gain all the way down is so any noise going into the mic does not affect the setting.
You have to turn your mic gain up for someone to hear you.

 

[doffo]

Thanks again DUH! I should of known that lol! Either way. Least I got a general direction on where to start. Thanks everyone!

 

[9C1Driver]

Thanks for the help so far.

So since I would have to set it with the mic gain all the way down.. should I keep it all the way down when I go to use it on the KL-203P amp?

With that radio and amp combo set the Grant xl to 1.5 watts dead key, it should swing 10-12 watts. On SSB you should set it for a modulated peak of 14-16 watts.

Your done, don't mess with anything else. Those settings will work fine with a KL203 amplifier.

 

[The Bruce]

This is best left done to someone who has the knowledge and the right equipment. On the other hand there is no way to learn unless you dive in and do it.
The alignment procedures can be found on the cbtricks website.
Specifically this file Pages 48-63 of the service manual
Best advice : Don't turn anything unless your sure!

This can't be stated enough. Get your radio aligned by a trusted source. Some are mentioned here.

If you have all of the available equipment, do so yourself.

If you don't, please don't take your equipment some hack-shack.

 

[The Bruce]

This can't be stated enough. Get your radio aligned by a trusted source. Some are mentioned here.

If you have all of the available equipment, do so yourself.

If you don't, please don't take your equipment some hack-shack.

Okay, that was a little vague. If we're talking about CBs, I'd go with DTB Radios.

 

[doffo]

Thanks for the input on the settings.

I think what I will do is out of my four CBs, I will clean one up and get it sent to someone who can do great work and have them set it to 1 1/2 watt deadkey and 10 watts swing, and set the SSB to 14-16 watts.

Now.. I know I should know, but whos a very trustful resource here that does a tune/alignment on radios for a reasonable price.

 

[doffo]

Okay, that was a little vague. If we're talking about CBs, I'd go with DTB Radios.

Thanks! Just seen that as I typed that last message, but I will contact them and see what they can do.

 

[doffo]

DTB got back with me, but they said doing 10-12ish watts of a swing with a 1.5 watt deadkey would be driving it too hard? Max that you could do is about 5 watts so there is minimal distortion and a clean signal....

Did I ask the wrong thing or what am I missing?