The Defpom Forum, for RadioMods, S&M Software and Music by The Defpom

I just picked up a used Uniden PC244 AM-SSB radio. SSB works great, but there is no forward swing on AM at all. I can set the dk (vr10) anywhere from 1/2 watt up to about 7 watts and have no forward swing when I modulate. If I turn it above 7 watts it will begin to swing backwards. The swr's on antenna are very good by the way.

Radio doesn't appear to be hacked at all! I'm not even sure the case was ever opened up before I opened it. Any idea where to start to find the problem?

Thanks!

just a thought did you check for any cold solder joints. Also check the am regulator. I would start by keying the radio and flex the board a little bit with you finger and see if you audio comes back intermittently. I would have to look at the schematic to be able to tell you much more. I will see if i have that shcemaic.

MIKE

speedracer6g wrote:just a thought did you check for any cold solder joints. Also check the am regulator. I would start by keying the radio and flex the board a little bit with you finger and see if you audio comes back intermittently. I would have to look at the schematic to be able to tell you much more. I will see if i have that shcemaic.

MIKE

Ok, just to clear things up, the audio does work, just no forward swing on the watt meter at all. The meter on the radio does move and reports are good. But I'd like to see it do at least some swing. But I will try what you said to see if that does anything. Thanks.

Not finding any cold solder points at all on this PC244. I believe I may have a bad AM regulator but not sure. Can you tell me how to check it? Have been doing some reading on some unidens that had similar problems and even found a mod on the PC122 that you could do to keep the problem from happening again. That would be good to know on this radio too!

Still haven't found any schematics though.

on the pc 244 vr5 is the modulation adjustment vr10 is am power vr11is SSB power adj. Check to make sure that vr5 is not turned down.

Thanks for the reply. VR5 isn't turned down .. In fact it was turned almost all the way up and sounded as though it was over modulating. I got it to sound better by turning it down to about half way.

I've ordered another watt meter and will see what it shows. Should be here this week.

what kind of mic are you useing on this radio?

woody wrote:what kind of mic are you useing on this radio?

I've tried different ones. Currently a RK-56.

If the power meter you are using to check this radio only measures average power, then that's probably why you're seeing backward swing... if you get a meter that reads PEP (forward swing) it might read different, your radio might not have anything wrong with it. Just a suggestion.

-Exit

Exit_Thirteen wrote:If the power meter you are using to check this radio only measures average power, then that's probably why you're seeing backward swing... if you get a meter that reads PEP (forward swing) it might read different, your radio might not have anything wrong with it. Just a suggestion.

-Exit

Even if it is average power, should I be seeing a backwards swing?? That doesn't seem right to me. My other radios all show forward swing.

It's not always the case, my Uniden Pro 810e base station deadkeys 4 watts on AM, and when I modulate, it pretty much just stays there on my Bird 43A wattmeter. It wiggles just a little bit, but the most part it stays right at about 4 watts.

However, when I use my Dosy 4001 test center, I show 4 watts deadkey to 18 watts of swing. If that radio is out of alignment a bit or deadkey is set too high, it's possible that it can swing backwards, I've seen this on a lot of radios with my Bird meter, especially if the deadkey was set higher than 4-5 watts.

-Exit