Smokey 23 channel troubleshooting no tx/rx

[guitar_199]

G'morning. (just barely....but it still is morning in Houston!)

This has been "playing through my mind" overnight.... I want to ask MAYBE one.....MAYBE several questions.... JUST to be SURE that I am clear on where we are. I am having to use you as my "eyes and ears" because you have the radio!

Let me go back to RCV.

You say that it is receiving signal. From that... I am taking that...if you have an antenna hooked to it...and there is "chatter on a channel"......you can TUNE to that channel...and HEAR the channel audio....and you can hear it at a decent volume.

Is that correct?

---------
On TX

You say that it transmits a carrier. From that.... I am taking that you can put the radio on a channel.....key the mic...... and .... on ANOTHER RADIO (an HT or whatever it is) you can SEE the needle go up and HEAR a FULL QUIETING effect..... even though there is NO modulation heard.

Is that correct?

Also on TX

WHEN you key up ......does the meter ON the Smokey 23 seem to SHOW that the carrier output is working? I realize that the meter is flaky.... at least on RCV.....but when you key.... does it JUMP UP to a different place and stay there as long as you hold the mic keyed??? Also.... assuming that the meter DOES jump up in TX..... IF you try to modulate....do you see any "wiggle" in the Smokey 23's meter?

There may be more as I think about this.....

 

[Champo]

G'morning. (just barely....but it still is morning in Houston!)

This has been "playing through my mind" overnight.... I want to ask MAYBE one.....MAYBE several questions.... JUST to be SURE that I am clear on where we are. I am having to use you as my "eyes and ears" because you have the radio!

Let me go back to RCV.

You say that it is receiving signal. From that... I am taking that...if you have an antenna hooked to it...and there is "chatter on a channel"......you can TUNE to that channel...and HEAR the channel audio....and you can hear it at a decent volume.

Is that correct?

---------
On TX

You say that it transmits a carrier. From that.... I am taking that you can put the radio on a channel.....key the mic...... and .... on ANOTHER RADIO (an HT or whatever it is) you can SEE the needle go up and HEAR a FULL QUIETING effect..... even though there is NO modulation heard.

Is that correct?

Also on TX

WHEN you key up ......does the meter ON the Smokey 23 seem to SHOW that the carrier output is working? I realize that the meter is flaky.... at least on RCV.....but when you key.... does it JUMP UP to a different place and stay there as long as you hold the mic keyed??? Also.... assuming that the meter DOES jump up in TX..... IF you try to modulate....do you see any "wiggle" in the Smokey 23's meter?

There may be more as I think about this.....

Lol no worries. It is still morning here in Oregon so good afternoon to you! Ask all of the questions you need to. I spent many years as the Lead Technical Trainer for Jacuzzi Group Worldwide's spa division prior to relocating to Oregon. I was responsible for conducting regional and international training seminars. When I wasn't traveling my time was dedicated to troubleshooting issues that dealer technicians were unable to resolve over the phone so I can fully appreciate the service you guys are providing and the difficulty in troubleshooting something that you cannot see and are fully reliant on the information being fed to you from the other side. Bad info in begets bad info out. Sometimes the same questions need to be asked multiple times to make sure you aren't chasing ghosts. Anyways I digress.

So, back to the radio. I'll start with how it worked prior to me messing with it and the troubleshooting that was done. When I figured out that the Midland adapter I had brought in the receive (no mic, no receive) I attempted to transmit with the Cobra mic plugged into the Midland adapter. The radio is connected to an 11m dipole because the SWR is completely flat on it. Here in the valley ch. 20 is used by locals and we have a local net check in on Wednesday nights. I picked up the radio to use just for Wednesday nights in honor of #WaybackWednesday. My point in all of that nonsense rambling is that I have multiple guys to chat with here in the valley that can provide honest feedback. I have a cobra handheld and was using that to monitor my transmission. When the mic is keyed a strong carrier is visible on the handheld but no modulation was heard on the handheld. I wanted to eliminate the proximity issue of the handheld to the dipole so I went out to my mobile and contacted a guy I know that is about 7 miles away. I told him that I would go back inside and transmit a carrier 3 times in a row and to see if he received it. I then hopped back in the mobile and he confirmed that he received the carrier 3 times in a row. He said the carrier was strong and was hitting him at about 7lbs. During all of this I failed to look at what the meter on the Smokey was doing. After all of that was done I went through and recapped the radio because the local consensus was that a cap was responsible for modulation on older radios as opposed to an audio chip.

So here is where we stand today. The radio transmits a carrier that is visible on the handheld that appears to be at the same strength as it was prior to the recap. I can hear the guys in the valley via the Smokey just as I can with any of my functional radios. The meter will back swing on receive as well as when the mic is keyed. I sure made that short story long didn't I?

So right now, if we exclude the meter, everything appears to work properly except for modulation. If you key up when in PA the speaker goes quiet. If you key up in CB the speaker goes quiet. Basically I'm just missing modulation. As for the meter jumping question, it bottoms out too quickly to see if there is any jumping when speaking.

On a separate note, were you able to read my post on contact cleaner and DeoxIT? What are your thoughts?

Thanks,

Jay

 

[Champo]

Here is a picture of the meter with radio on, empty channel. The second picture is transmit on the same channel.

 

[guitar_199]

On the DeOxit...... i had seen it...... and I DO know of it's GREAT reputation....but have never bought any.... so I don't have direct experience.

I DID go look at the product literature and from what I see there...and what I know of other products....... I will say this.....

The D5 looks to be a contact cleaner. Good for switches and contacts.... NOT SO GOOD for potentiometers/controls. The Fader Lube is more for controls. It has lubricant that helps lube the pots moving parts. If you use contact cleaner on pots....I HAVE HEARD that it can flush all lubricant out of the shaft.shank area and cause the pot to dry out/seize up/lock up. I have not HAD it happen...but have heard of it.

I am hoping that someone will see this and jump in with an opinion,,,,

Also......if you have never heard of this guy on YouTube...."Mikes Radio Repair"
Here is a video of him talking about a lot of chems that he uses. Roll out to about 13:45 or so....he starts talking about all of the DeOxit products that he uses....he uses a number of them. Maybe that will tell you something.

 

[Champo]

On the DeOxit...... i had seen it...... and I DO know of it's GREAT reputation....but have never bought any.... so I don't have direct experience.

I DID go look at the product literature and from what I see there...and what I know of other products....... I will say this.....

The D5 looks to be a contact cleaner. Good for switches and contacts.... NOT SO GOOD for potentiometers/controls. The Fader Lube is more for controls. It has lubricant that helps lube the pots moving parts. If you use contact cleaner on pots....I HAVE HEARD that it can flush all lubricant out of the shaft.shank area and cause the pot to dry out/seize up/lock up. I have not HAD it happen...but have heard of it.

I am hoping that someone will see this and jump in with an opinion,,,,

Also......if you have never heard of this guy on YouTube...."Mikes Radio Repair"
Here is a video of him talking about a lot of chems that he uses. Roll out to about 13:45 or so....he starts talking about all of the DeOxit products that he uses....he uses a number of them. Maybe that will tell you something.

I need to clarify something that I said about the PA function that was inaccurate. When you switch to PA there is a static that is heard through the speaker that sounds very similar to the static when the radio is in cb mode (unlike the galaxy I'm familiar with). Once the mic is keyed the static disappears and a high pitched whine is heard.

 

[guitar_199]

From the two pics.... I can't tell that the meter is working at all. Both shots show it way low down at the left end of the scale.

But ..based on everything else you have said this morning.... (NOT counting the metering yet!).... it sounds like the only thing that is wrong is the audio modulation of the RF output that is not working.

If you have "on channel" receive with "loud clear" audio.......

Then... your audio power circuits are working and working well.

In MOST of these AM radios..... the SAME audio power circuit feeds into a transistor that essentially "varies" the DC voltage fed to the final and lots of times the driver.

You are GETTING carrier out........but NO modulation..... SOMETHING is wrong in that AM/Regulator area... and is usually fairly simple to diagnose and fix.... ONCE you get that SAMS book on it.

ONce you get it.....do you have a way to scan portions of the schematics so that I can locate the AM/Regulator circuits....? Even phone shots would be a help.

But when you get that SAMS....there will be voltage readings ALL OVER THAT SCHEMATIC ...... we can check the ones in the area of concern....and make some judgements on what is going on.

 

[Champo]

From the two pics.... I can't tell that the meter is working at all. Both shots show it way low down at the left end of the scale.

But ..based on everything else you have said this morning.... (NOT counting the metering yet!).... it sounds like the only thing that is wrong is the audio modulation of the RF output that is not working.

If you have "on channel" receive with "loud clear" audio.......

Then... your audio power circuits are working and working well.

In MOST of these AM radios..... the SAME audio power circuit feeds into a transistor that essentially "varies" the DC voltage fed to the final and lots of times the driver.

You are GETTING carrier out........but NO modulation..... SOMETHING is wrong in that AM/Regulator area... and is usually fairly simple to diagnose and fix.... ONCE you get that SAMS book on it.

ONce you get it.....do you have a way to scan portions of the schematics so that I can locate the AM/Regulator circuits....? Even phone shots would be a help.

But when you get that SAMS....there will be voltage readings ALL OVER THAT SCHEMATIC ...... we can check the ones in the area of concern....and make some judgements on what is going on.

I just confirmed a big problem. Cb transmissions are heard through the PA when the CB is in PA. I placed the Cb in PA and then transmitted with handheld and I was heard on the speaker connected to the PA connection. The PA does not seem to be isolated from the CB circuit.

 

[guitar_199]

YO know what this sounds like..... in a way??? Maybe...... NORMAL.

If you switch to PA from CB and then KEY the mic.....

The mic is now HOT......and possibly VERY close to the speaker you are plugging in.....

IF the mic can "hear" the speaker....... it will whistle and squeal like crazy.

Can you repeat that test and make SURE that the mic is either "rolled down in volume WAY down" or that the speaker is far enough away...so that it doesn't couple.

Just the main thing is..... try to get the mic turned down....OR...keep the mic away from the speaker as much as possible. They can not be within earshot of each other or you WILL get a screeching squeal.

I need to clarify something that I said about the PA function that was inaccurate. When you switch to PA there is a static that is heard through the speaker that sounds very similar to the static when the radio is in cb mode (unlike the galaxy I'm familiar with). Once the mic is keyed the static disappears and a high pitched whine is heard.

 

[guitar_199]

THAT is interesting.....but again....with the SAMS schematic....we will be abloe to get to the bottom of that. They MAY have DESIGNED it that way......

The reason I say that.....

If somebody put one in their car....and wired up a PA speaker outside the car..... THIS would let them switch to PA...and they could then hear the radio traffic over the PA speaker.

What I would EXPECT if this IS the case........

When you key the mic up...and talk....it would SHUT OFF the CB and NOW it would output your mic audio.

Again, if you can repeat this test.... just be sure to either roll the volume down on the mic.... or KEEP THEM APART.....or both.

If you turn the mic down....and it doesn't squeal any more.... you SHOULD be able to sneak it up just a little bit....then key up and make some noise....and see if it comes out the PA speaker.

I just confirmed a big problem. Cb transmissions are heard through the PA when the CB is in PA. I placed the Cb in PA and then transmitted with handheld and I was heard on the speaker connected to the PA connection. The PA does not seem to be isolated from the CB circuit.

 

[Champo]

YO know what this sounds like..... in a way??? Maybe...... NORMAL.

If you switch to PA from CB and then KEY the mic.....

The mic is now HOT......and possibly VERY close to the speaker you are plugging in.....

IF the mic can "hear" the speaker....... it will whistle and squeal like crazy.

Can you repeat that test and make SURE that the mic is either "rolled down in volume WAY down" or that the speaker is far enough away...so that it doesn't couple.

Just the main thing is..... try to get the mic turned down....OR...keep the mic away from the speaker as much as possible. They can not be within earshot of each other or you WILL get a screeching squeal.

I just confirmed the cb is bleeding over to PA. There are locals on ch. 20 right now and if I switch to PA they can be heard through the external speaker plugged into the PA jack.

 

[guitar_199]

I think you are VERY close......BUT.....the "keys" to getting it done.....are in that SAMS manual that should be "winging its way to you"!

This is all sounding very simple.

 

[Champo]

I think you are VERY close......BUT.....the "keys" to getting it done.....are in that SAMS manual that should be "winging its way to you"!

This is all sounding very simple.

So if I key the mic, while in PA, the locals on ch. 20 cut out and a high pitched whine is heard. Handheld is off. Sam's manual should be here next Thursday and I can send you pictures or scans. My scanner isn't that great so pictures will probably be clearer.

 

[guitar_199]

1) I still think it is the microphone coupling. Did you turn the microphone knob to 0? This is a D104 right? Cut that baby ALL THE WAY OFF and then.....key up....does it still squeal. And how close IS the speaker to the microphone when you do this? And...is the speaker pointing right AT you when you are keying the mic?

2) Pics SHOULD be fine.

I have an app on my Android phone...... in the Google Play Store called "CamScanner".
It takes pictures....BUT it puts them into a PDF file format....
When you scale them up bigger... you don't lose sharpness.......
But pics is cool.... I may have to "zero you in" on an area......

What I may do...to save some time if you are game......
Get you my email address.....then you can transfer them straight to me and save all this time and delays here. If you find that acceptable.....

 

[Champo]

1) I still think it is the microphone coupling. Did you turn the microphone knob to 0? This is a D104 right? Cut that baby ALL THE WAY OFF and then.....key up....does it still squeal. And how close IS the speaker to the microphone when you do this? And...is the speaker pointing right AT you when you are keying the mic?

2) Pics SHOULD be fine.

I have an app on my Android phone...... in the Google Play Store called "CamScanner".
It takes pictures....BUT it puts them into a PDF file format....
When you scale them up bigger... you don't lose sharpness.......
But pics is cool.... I may have to "zero you in" on an area......

What I may do...to save some time if you are game......
Get you my email address.....then you can transfer them straight to me and save all this time and delays here. If you find that acceptable.....

I'm totally good with exchanging emails. Disregard the squealing. It was the result of an amplified speaker I was using. I ditched it for a passive and it's gone. What I did find though is that if I'm in PA and key mic it transmits a carrier to the handheld. It's not as strong as in CB mode but it is there.

 

[guitar_199]

I copy. Now THAT is a problem.
Typically when you switch from Cb to PA all of the transmit voltages are disabled... so NO carrier should be generated.

I wonder if the CB/PA switch itself is flaky. As in.... you switch it to PA....BUT it leaves the RF circuits powered up? THAT could answer for BOTH the CB audio over the PA speaker AND the transmit a carrier when keyed in PA issue.

I'm totally good with exchanging emails. Disregard the squealing. It was the result of an amplified speaker I was using. I ditched it for a passive and it's gone. What I did find though is that if I'm in PA and key mic it transmits a carrier to the handheld. It's not as strong as in CB mode but it is there.