Smokey 23 channel troubleshooting no tx/rx

[guitar_199]

Good job on finding that mic wiring diagram. THAT could be crucial....especially with the sound that you describe when you plug a speaker into the out jack.

For one in most of these electronically switched radios.... one of the BIG things the receive wire does is "ground the internal speaker". If there might be a miswire on the mic... that grounding COULD be happening through a wrong connection .... thus creating an audio oscillator.

I need to go back through here and dig out what you are doing with the microphone and an adapter..... to see what you mean about "when the mic adapter is removed you lose what little sound is present".

The way I am...I look for simplified ways to do things.

Looking at the Romar mic wiring..... if you pull everything out of the mic jack...and use a wire..... pin 2 is the shield/ground that does the switching. If you carefully touch a wire from pin 2 to pin 4 THAT should "simulate" correct wiring for the RCV circuits. THen separately....touching pin 2 to pin 3 should turn on transmit.....

It would be interesting to know what you see there.

Make sure you have a dummy load or antenna on the connector whenever you try transmit. Just in case it works. Antenna would be better for receive.....

While trying the receive...if you do have another radio and can power it up....it would be good to try transmitting on IT...and see if this radio senses it....(like...meter moves)....

 

[Champo]

Good job on finding that mic wiring diagram. THAT could be crucial....especially with the sound that you describe when you plug a speaker into the out jack.

For one in most of these electronically switched radios.... one of the BIG things the receive wire does is "ground the internal speaker". If there might be a miswire on the mic... that grounding COULD be happening through a wrong connection .... thus creating an audio oscillator.

I need to go back through here and dig out what you are doing with the microphone and an adapter..... to see what you mean about "when the mic adapter is removed you lose what little sound is present".

The way I am...I look for simplified ways to do things.

Looking at the Romar mic wiring..... if you pull everything out of the mic jack...and use a wire..... pin 2 is the shield/ground that does the switching. If you carefully touch a wire from pin 2 to pin 4 THAT should "simulate" correct wiring for the RCV circuits. THen separately....touching pin 2 to pin 3 should turn on transmit.....

It would be interesting to know what you see there.

Make sure you have a dummy load or antenna on the connector whenever you try transmit. Just in case it works. Antenna would be better for receive.....

While trying the receive...if you do have another radio and can power it up....it would be good to try transmitting on IT...and see if this radio senses it....(like...meter moves)....

What I meant by adapter was I had assumed that the mic wiring was for a Midland since the cobra plug does nothing when plugged in. With a mic with a cobra plug plugged into the Midland adapter you would get receive and be able to transmit a carrier but with no modulation. In order to get any sound out you have to have a mic connected. That is why I think it partially worked before. The Midland uses 4 wires where as this smokey appears to have used 5. On a separate note the connections you asked about are for the black box labeled Murata CFU455. I'm home now so I can plug it in and try the mic test.

 

[guitar_199]

"On a separate note the connections you asked about are for the black box labeled Murata CFU455. I'm home now so I can plug it in and try the mic test."

I am a little confused by that one.

the test from pin 2 to pin 4 for receive and 2 to pin 3 for transmit should be on the front panel mic connector. Perhaps I am misunderstanding.

So.....according to the Romar mic wiring diagram... the radio should have 4 pins..... that is all of the pins that are described. Are you saying that when you pull the mic out of the connector....there are 5 pins?

 

[Champo]

What I meant by adapter was I had assumed that the mic wiring was for a Midland since the cobra plug does nothing when plugged in. With a mic with a cobra plug plugged into the Midland adapter you would get receive and be able to transmit a carrier but with no modulation. In order to get any sound out you have to have a mic connected. That is why I think it partially worked before. The Midland uses 4 wires where as this smokey appears to have used 5. On a separate note the connections you asked about are for the black box labeled Murata CFU455. I'm home now so I can plug it in and try the mic test.

So it looks like 2-3 does the receive and 2-4 does transmit because shuts the green meter light off. The red one does not activate though. It mimics the adapter with mic. The volume coming from the speaker is still muted. There's definitely an issue with power flow on the board because when I touch a meter lead near the front of the board the volume from the speaker increases to normal levels. It isn't receiving though beause there is chatter on the channel (I can hear it on the other cb) but not on the smokey.

 

[Champo]

So it looks like 2-3 does the receive and 2-4 does transmit because shuts the green meter light off. The red one does not activate though. It mimics the adapter with mic. The volume coming from the speaker is still muted. There's definitely an issue with power flow on the board because when I touch a meter lead near the front of the board the volume from the speaker increases to normal levels. It isn't receiving though beause there is chatter on the channel (I can hear it on the other cb) but not on the smokey.

Two different issues. You asked about the solder connections on the board and that was what I was referencing. There are only 4 pins for the mic plug on the radio. Cobra and midlands both use 4 wires for 4 pins but if you look at that astatic wiring info it references 5 wires (4+shield) for the smokey. That's why I think there was no modulation originally. My bigger problem now though is finding the problem I created.

 

[Champo]

Two different issues. You asked about the solder connections on the board and that was what I was referencing. There are only 4 pins for the mic plug on the radio. Cobra and midlands both use 4 wires for 4 pins but if you look at that astatic wiring info it references 5 wires (4+shield) for the smokey. That's why I think there was no modulation originally. My bigger problem now though is finding the problem I created.

 

[Champo]

Holey $hit it's working! There was a tiny piece of wick left connecting two points on one cap! It's now transmitting a carrier but no modulation.

 

[Champo]

Holey $hit it's working! There was a tiny piece of wick left connecting two points on one cap! It's now transmitting a carrier but no modulation.

The meter seems to be inoperable to a degree. It back swings when receiving as opposed to moving forward. Small potatoes. Now I just need to troubleshoot the no modulation or figure out a way to wire an astatic up to it.

 

[Dmans]

Champo,
These pictures are from the same area of the board you posted earlier.
Seems to show a poor solder connection.



73
David

 

[Champo]

Champo,
These pictures are from the same area of the board you posted earlier.
Seems to show a poor solder connection.
View attachment 44551
View attachment 44553

I appreciate the reply. I'll clean that one up. At the moment I've got her calling working a stupid piece of solder wick got left behind and was bridging a cap. Rookie mistake. So I have receive and can transmit a carrier but no modulation. I believe that is probably an issue related yo mic wiring. I found an old file by astatic that showed that it required 5 wires ( 4+shield). I only have 4 wire mics so unless their is a work around it sounds like I need a 6 wire mic (see pictures). Let me know your thoughts. Also the meter seems to deflect on receive as opposed to increase but that's small potatoes at this point.

 

[guitar_199]

GOOD WORK Champo! That is "sticking to it"! And when I said a whisker..... those solder wick whiskers are pretty small....but they are enough.

Me and the Missus ducked out for dinner and I am pretty beat. if you don't mind, I'll touch base in the morning.

Excellent work though! Excellent.

OHHHHH.... and check the PA function again...... things may or may not be different now that you are "back to where you originally were".

See you in the morning.... if you are around.

 

[Champo]

GOOD WORK Champo! That is "sticking to it"! And when I said a whisker..... those solder wick whiskers are pretty small....but they are enough.

Me and the Missus ducked out for dinner and I am pretty beat. if you don't mind, I'll touch base in the morning.

Excellent work though! Excellent.

OHHHHH.... and check the PA function again...... things may or may not be different now that you are "back to where you originally were".

See you in the morning.... if you are around.

I'll be around and I appreciate all of the help. Enjoy that nap! You weren't lying when you said tiny! Pure luck that I found it. I'll check the PA. Forgot to do that.

 

[Champo]

I'll be around and I appreciate all of the help. Enjoy that nap! You weren't lying when you said tiny! Pure luck that I found it. I'll check the PA. Forgot to do that.

So to recap...pun intended...it is operational and receives. The meter acts funky on receive and actually back dips as opposed to moving forward when someone is modulating (small potatoes at this point). Now to the PA. A high pitched oscillating whine or hum can be heard through a speaker but no modulation. An audible click from the key up can be heard though. If the mic information that I found from Astatic is correct it would seem to indicate that a 6 wire mic would be required with one wire unused (white, shield, blue, black, red and yellow unused). If that's accurate then I won't be able to do anything beyond that as all the mics I have are 4 wire mics I believe...unless there is a work around.

 

[Dmans]

Champo,
You would only need a 6 (or 5) wire microphone if you are using the Astatic brand microphone. Check the link below from Lou Franklin. I am sure with his information, you will figure it out.

http://cbcintl.com/docs/mikewire.htm

It is possible one of your capacitors is installed with reversed polarity causing your backwards deflecting RX meter reading.

73
David

 

[Champo]

Champo,
You would only need a 6 (or 5) wire microphone if you are using the Astatic brand microphone. Check the link below from Lou Franklin. I am sure with his information, you will figure it out.

http://cbcintl.com/docs/mikewire.htm

It is possible one of your capacitors is installed with reversed polarity causing your backwards deflecting RX meter reading.

73
David

Thank you David. I have an Astatic D104m6b mic. I think this will be my best bet then. It looks like it has 6 wires in it.