Smokey 23 channel troubleshooting no tx/rx

[guitar_199]

Good morning Champo! First .... "my point of view on the microphone issue". (others please chime in when you discover stupidity on my part!!!! I welcome it!!!!)

(by the way....at the VERY BOTTOM after typing all of this in..... it occurred to me that... you may ALREADY KNOW all this...... and that telling you anyway...MIGHT make you want to "beat the s##t" out of me for feeding it to you (that was SNOT of course!!!!! ). That said... I am leaving it here just in case. It could help someone else!)

ON the subject of the microphone..... the diagram you send...... appears to be attaching a 5 wire microphone to the Romar ACT-1914 radio.

I went out and found the Astatic Mic Wiring book and it tells me that nominal Astatic color code is:

White - Audio
Sh (shield) -Audio Shield
Blue - Switching common
Red - Transmit (when grounded)
Black - Receive (when grounded)
Yellow - Special Receive Ground (not normally used)

Now, from the Romar ACT-1914 wiring part, I see that the jack on the radio is:

1 - Audio
2 - Ground
3 - Receive (when grounded)
4 - Transmit (when grounded)

So .... two things are going on in a mic connector.... audio and RX/TX switching

Iin the Astatic microphone in the manual (and INDEED many others with more than 4 wires!) THEY have a separate Ground wire for audio (Sh) and another one for mode switching (blue).

A common 4 wire microphone has the same function to perform the same two functions....... only difference being...... the audio shield and the switching common.... are the same wire!!!!!

That is why, on the Astatic mic you see SH and BLUE tied together....to MAKE them the same function.

So the TRICK becomes...... taking the mic that YOU HAVE....and determining what function is on each color wire and make a little "table" of

COLOR = FUNCTION

Very typically white IS audio.....but PERHAPS not always....

Red/black are USUALLY transmit and receive...but YOUR mic may put it on a different color......

Typically the other wire is a plain uninsulated wire....or they use the braid from the shielded audio cable..(most of the time audio cables are a two wire shielded cable) ... and they just use the shield for ALL GROUND purposes.

So, back to the trick.... we KNOW what function needs to go on what PIN of the radio connector........but we may be unsure of what COLOR coming out of the mic serves WHAT function! And it is not always OK to use an adapter....because some manufacturers did not adhere to the same standard as others......

Usually you can determine this by opening the back of the mic and also opening up that mic connector. In a four wire mic the easiest thing to pick out will be the shield. Very commonly it has no insulation.... OR..... you can see one small cable that has a center wire coming out....and also has a shield wire coming out. Once you KNOW the ground.....

You will most likely have a RED and a BLACK. Set your meter for OHMS or for CONTINUITY..... clip ONE lead to that shield... the other touch it to the red and black... ONE of them should BEEP. IF it does..... KEY the mic. The beep should stop. If it does.... THAT one is your RCV wire. Now....clip still on the shield..... touch the OTHER wire. IT should NOT BEEP ...... UNTIL YOU KEY up the mic. When you release the key.... it should go silent. THAT is the TX wire.

The remaining wire.... is your audio.

With all of that.... you now know WHAT color is what function on you mic....
AND
You know what function needs to go to what pin on the connector
(be sure to use the numbers on the mic connector!)

Just unsolder the mic wires from the connector...and resolder each color/function to the correct pin for the radio.

Now you KNOW that mic matches the radio....for certain.

 

[Champo]

Good morning Champo! First .... "my point of view on the microphone issue". (others please chime in when you discover stupidity on my part!!!! I welcome it!!!!)

(by the way....at the VERY BOTTOM after typing all of this in..... it occurred to me that... you may ALREADY KNOW all this...... and that telling you anyway...MIGHT make you want to "beat the s##t" out of me for feeding it to you (that was SNOT of course!!!!! ). That said... I am leaving it here just in case. It could help someone else!)

ON the subject of the microphone..... the diagram you send...... appears to be attaching a 5 wire microphone to the Romar ACT-1914 radio.

I went out and found the Astatic Mic Wiring book and it tells me that nominal Astatic color code is:

White - Audio
Sh (shield) -Audio Shield
Blue - Switching common
Red - Transmit (when grounded)
Black - Receive (when grounded)
Yellow - Special Receive Ground (not normally used)

Now, from the Romar ACT-1914 wiring part, I see that the jack on the radio is:

1 - Audio
2 - Ground
3 - Receive (when grounded)
4 - Transmit (when grounded)

So .... two things are going on in a mic connector.... audio and RX/TX switching

Iin the Astatic microphone in the manual (and INDEED many others with more than 4 wires!) THEY have a separate Ground wire for audio (Sh) and another one for mode switching (blue).

A common 4 wire microphone has the same function to perform the same two functions....... only difference being...... the audio shield and the switching common.... are the same wire!!!!!

That is why, on the Astatic mic you see SH and BLUE tied together....to MAKE them the same function.

So the TRICK becomes...... taking the mic that YOU HAVE....and determining what function is on each color wire and make a little "table" of

COLOR = FUNCTION

Very typically white IS audio.....but PERHAPS not always....

Red/black are USUALLY transmit and receive...but YOUR mic may put it on a different color......

Typically the other wire is a plain uninsulated wire....or they use the braid from the shielded audio cable..(most of the time audio cables are a two wire shielded cable) ... and they just use the shield for ALL GROUND purposes.

So, back to the trick.... we KNOW what function needs to go on what PIN of the radio connector........but we may be unsure of what COLOR coming out of the mic serves WHAT function! And it is not always OK to use an adapter....because some manufacturers did not adhere to the same standard as others......

Usually you can determine this by opening the back of the mic and also opening up that mic connector. In a four wire mic the easiest thing to pick out will be the shield. Very commonly it has no insulation.... OR..... you can see one small cable that has a center wire coming out....and also has a shield wire coming out. Once you KNOW the ground.....

You will most likely have a RED and a BLACK. Set your meter for OHMS or for CONTINUITY..... clip ONE lead to that shield... the other touch it to the red and black... ONE of them should BEEP. IF it does..... KEY the mic. The beep should stop. If it does.... THAT one is your RCV wire. Now....clip still on the shield..... touch the OTHER wire. IT should NOT BEEP ...... UNTIL YOU KEY up the mic. When you release the key.... it should go silent. THAT is the TX wire.

The remaining wire.... is your audio.

With all of that.... you now know WHAT color is what function on you mic....
AND
You know what function needs to go to what pin on the connector
(be sure to use the numbers on the mic connector!)

Just unsolder the mic wires from the connector...and resolder each color/function to the correct pin for the radio.

Now you KNOW that mic matches the radio....for certain.

Good Morning Guitar_199! Nope all info is welcome and any info I may already have is just confirmation that it is correct. I'm in luck because I just so happen to have an Astatic D104m6b mic doing a whole lot of nothing...well besides collecting dust that is. It didn't sound all that great on any of my other radios so it never got used. I think this will be my best bet because everything should match up with Astatic's information so as long as I don't botch the soldering job and we should be in business. I'll have some free time this afternoon to rewire it so we'll know soon enough. On another note, for educational purposes since my radio knowledge is virtually non existent, how can one radio get away with three wires while another requires 5? I pose this question because I also purchased a Pace 113 that hasn't yet arrived and I may use that Astatic on it if it doesn't work out with the Smokey. It only uses 3 vs 5 on the Smokey.

 

[guitar_199]

Where a lot of the difference comes from is ACTUALLY in the radio! It depends on the type of "switching" used.

In most more modern radios (for SWITCHING) they use three wires..... a common (usually ground).... and then TWO more wires..... one that enables RCV functions when it is grounded (and thereby DISables them when it is OPEN) AND ANOTHER WIRE... that enables TX functions when it is grounded (and thereby DISables TX when it is open. For that reason... only ONE of the TWO wires can be grounded at once....and that is the job of the PTT switch. When it is UNPRESSED the TX wire is open but the RCV wire is connected to common. When you press it...it OPENS the receive wire and connects the TX wire...and now you are transmitting.

In the ABOVE situation...if YOUR microphone SHARES the audio shield with the switching ground.... then you only need ONE more wire for the AUDIO...and you have a 4 wire mic.

HOWEVER.... it YOUR microphone DOES NOT SHARE the audio shield with the switching ground... you NOW have a FIVE wire mic. Again....however.... in most of these... you can twist the audio shield AND switching ground TOGETHER and solder them to the ground pin of a 4 wire connector.... so you can use a 5 wire mic on a 4 pin radio.

All of THAT is for ELECTRONIC switching.

NOW for the OTHER case...... RELAY switching.

Many older relays have a RELAY inside...... essentially.... a SWITCH that is controlled by an electromagnet. IN THESE radios.....to SWITCH... you only need to GROUND the switching pin..... which starts current flowing in the relay coil.....which energizes the relay....which switches the switch!

IN THIS type of radio....... coming out of the microphone jack... you need a ground for the switching to happen...AND ONE MORE WIRE THAT GOES TO THE RELAY. When these two are NOT CONNECTED.... the relay is RELAXED....and the switch on the relay is wired to enable all of the receive functionality in the radio. When you touch them together...... the relay is ENERGIZED and the switch is NOW connecting up all of the transmit functionality. Wen THIS is the case..... the microphone CAN AGAIN share the audio shield WITH that switching ground..... so all you need is.....
1) audio pin, 2) ground pin, TX relay switching pin..... THREE WIRES!

 

[Champo]

Where a lot of the difference comes from is ACTUALLY in the radio! It depends on the type of "switching" used.

In most more modern radios (for SWITCHING) they use three wires..... a common (usually ground).... and then TWO more wires..... one that enables RCV functions when it is grounded (and thereby DISables them when it is OPEN) AND ANOTHER WIRE... that enables TX functions when it is grounded (and thereby DISables TX when it is open. For that reason... only ONE of the TWO wires can be grounded at once....and that is the job of the PTT switch. When it is UNPRESSED the TX wire is open but the RCV wire is connected to common. When you press it...it OPENS the receive wire and connects the TX wire...and now you are transmitting.

In the ABOVE situation...if YOUR microphone SHARES the audio shield with the switching ground.... then you only need ONE more wire for the AUDIO...and you have a 4 wire mic.

HOWEVER.... it YOUR microphone DOES NOT SHARE the audio shield with the switching ground... you NOW have a FIVE wire mic. Again....however.... in most of these... you can twist the audio shield AND switching ground TOGETHER and solder them to the ground pin of a 4 wire connector.... so you can use a 5 wire mic on a 4 pin radio.

All of THAT is for ELECTRONIC switching.

NOW for the OTHER case...... RELAY switching.

Many older relays have a RELAY inside...... essentially.... a SWITCH that is controlled by an electromagnet. IN THESE radios.....to SWITCH... you only need to GROUND the switching pin..... which starts current flowing in the relay coil.....which energizes the relay....which switches the switch!

IN THIS type of radio....... coming out of the microphone jack... you need a ground for the switching to happen...AND ONE MORE WIRE THAT GOES TO THE RELAY. When these two are NOT CONNECTED.... the relay is RELAXED....and the switch on the relay is wired to enable all of the receive functionality in the radio. When you touch them together...... the relay is ENERGIZED and the switch is NOW connecting up all of the transmit functionality. Wen THIS is the case..... the microphone CAN AGAIN share the audio shield WITH that switching ground..... so all you need is.....
1) audio pin, 2) ground pin, TX relay switching pin..... THREE WIRES!

Thank you for explaining that in a way that is easy to understand. So it sounds like I'll be in business with that D104m6b with either radio. So what do you think the likelihood is that rewiring that mic will fix all the issues that the smokey is currently experiencing? Well minus the meter issue that is.

 

[guitar_199]

Here is a snippet from the Pace-113 radio...showing the switching.
As I suspected... it is RELAY switched. They are using a 4 pin connector...but only three pins do anything.

Pin 1 is the audio (look inside the mic dotted box, they disconnect the mic in RCV)
Pin 4 is the XMT wire.....
Pin 2 is the common/shield (goes to the other side of the mic element AND the other side of the XMT switch.

So... only three wires do all the work!

[edited to add]
I forgot to mention... look at that relay in the bottom right corner.... the BOTTOM of the coil goes to CKT TRACE 95. That is MOST LIKELY just a VOLTAGE source. It just sits there all the time. The TOP contact of the coil goes over to the mic jack...pin 4. When you ground it... the relay energizes...and the "switching" happens.

 

[Champo]

Here is a snippet from the Pace-113 radio...showing the switching.
As I suspected... it is RELAY switched. They are using a 4 pin connector...but only three pins do anything.

Pin 1 is the audio (look inside the mic dotted box, they disconnect the mic in RCV)
Pin 4 is the XMT wire.....
Pin 2 is the common/shield (goes to the other side of the mic element AND the other side of the XMT switch.

So... only three wires do all the work!

[edited to add]
I forgot to mention... look at that relay in the bottom right corner.... the BOTTOM of the coil goes to CKT TRACE 95. That is MOST LIKELY just a VOLTAGE source. It just sits there all the time. The TOP contact of the coil goes over to the mic jack...pin 4. When you ground it... the relay energizes...and the "switching" happens.


View attachment 44565

I'm reposting the following because it popped in between you two messages so if you saw it I apologize..
Thank you for explaining that in a way that is easy to understand. So it sounds like I'll be in business with that D104m6b with either radio. So what do you think the likelihood is that rewiring that mic will fix all the issues that the smokey is currently experiencing? Well minus the meter issue that is.

 

[guitar_199]

That is CERTAINLY possible. A miswire on the microphone CAN create an audio path that could cause motorboating to occur.... oscillation. The only way to really know though... is to give it a shot.

The meter... may well be what DMan said.

The S meter works off of AGC related voltages. In the receive strip there are circuits that "tap off" a bit of received signal.... rectify it and filter it into a DC voltage that is proportional to "how strong the received signal is". They then feed that to the meter so that...when your signal is strong... the meter is driven further to the top... when the signal is weaker..it is not driven so far over. As modulation occurs ON THAT incoming signal..... that AGC related voltage will wiggle up and down with the modulation. Yours seems to be in "reverse" of the normal action. It will NOT stop the radio function though.... so let's see what it does as we get down the road!!!!

You are doing very good work! I am sure that you will be rewarded with a working radio!

So what do you think the likelihood is that rewiring that mic will fix all the issues that the smokey is currently experiencing? Well minus the meter issue that is.

 

[Champo]

That is CERTAINLY possible. A miswire on the microphone CAN create an audio path that could cause motorboating to occur.... oscillation. The only way to really know though... is to give it a shot.

The meter... may well be what DMan said.

The S meter works off of AGC related voltages. In the receive strip there are circuits that "tap off" a bit of received signal.... rectify it and filter it into a DC voltage that is proportional to "how strong the received signal is". They then feed that to the meter so that...when your signal is strong... the meter is driven further to the top... when the signal is weaker..it is not driven so far over. As modulation occurs ON THAT incoming signal..... that AGC related voltage will wiggle up and down with the modulation. Yours seems to be in "reverse" of the normal action. It will NOT stop the radio function though.... so let's see what it does as we get down the road!!!!

You are doing very good work! I am sure that you will be rewarded with a working radio!

Thank you for the wealth of knowledge, the encouragement and entertaining all of my questions. I'm fairly confident that all of the caps are in correctly with the possibility of one. Of the 21 caps, two weren't marked on the board (+). One was easy to figure out since the original caps went back in all of their respective spots and one leg was stretched in such a manner that there was no way to install it backwards. I also had a pic I took prior to doing the recap showing its position. The other however is questionable. It is blocked by wiring in the original pic and while I believe it went in the same way that it came out I will try reversing it.

 

[Champo]

Thank you for the wealth of knowledge, the encouragement and entertaining all of my questions. I'm fairly confident that all of the caps are in correctly with the possibility of one. Of the 21 caps, two weren't marked on the board (+). One was easy to figure out since the original caps went back in all of their respective spots and one leg was stretched in such a manner that there was no way to install it backwards. I also had a pic I took prior to doing the recap showing its position. The other however is questionable. It is blocked by wiring in the original pic and while I believe it went in the same way that it came out I will try reversing it.

I take that back. I did take a pic of it so I will compare it when I get back home. If it isn't a reversed cap then what would be the next possibility? Also, what function(s) do these perform (pic)?

 

[Champo]

I take that back. I did take a pic of it so I will compare it when I get back home. If it isn't a reversed cap then what would be the next possibility? Also, what function(s) do these perform (pic)?

Sorry I forgot to add the pic so I updated the previous post with it.

 

[guitar_199]

Don't change anything yet. When troubleshooting....... maintaining a tight control over changes is crucial. The meter....we just may have to wait until we can get our hands on the docs.

I am curious... do you plan to order that? Or...have you already?

For one.... the cap that you are questioning...... if we can determine what call out it is (C91, C22,... whatever) we can find it in the schematic and maybe judge whether or not it is in the correct direction.

But me... I am in favor of seeing if wiring the microphone "spot on" does anything "positive" before doing anything else.

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|
As far as "what do caps do".........

Essentially.... in a way... they act like tiny little low charge batteries... in that they tend to store and hold on to....electrical charges. They ALL block DC voltage.... DC can NOT pass through them.... ONLY AC.

Large ones (electrolytics)..... are often used as "filters" to smooth out the voltage that they are storing. That is why we see them in power supplies and things like that.

Smaller ones.... are used to "BLOCK DC....but.....allow signal to pass through" so that we can pass signal from one circuit element to another. IN the RF world they are also used to "tune" circuits... that is...... to configure circuits so that they work in a way that is sensitive to the frequency range. In other words..... some value of coil....with some value of capacitor across it.......will be TUNED to...and RESPOND to.....27 MHz and filter out everything else. In our radios...these are more often....NOT electrolytic...but may be a small plastic looking cap (some kind of film) or little yellow disc looking (usually ceramic). This does NOT cover all of them...but just so you get a general idea.

 

[Champo]

Don't change anything yet. When troubleshooting....... maintaining a tight control over changes is crucial. The meter....we just may have to wait until we can get our hands on the docs.

I am curious... do you plan to order that? Or...have you already?

For one.... the cap that you are questioning...... if we can determine what call out it is (C91, C22,... whatever) we can find it in the schematic and maybe judge whether or not it is in the correct direction.

But me... I am in favor of seeing if wiring the microphone "spot on" does anything "positive" before doing anything else.

---------
|
As far as "what do caps do".........

Essentially.... in a way... they act like tiny little low charge batteries... in that they tend to store and hold on to....electrical charges. They ALL block DC voltage.... DC can NOT pass through them.... ONLY AC.

Large ones (electrolytics)..... are often used as "filters" to smooth out the voltage that they are storing. That is why we see them in power supplies and things like that.

Smaller ones.... are used to "BLOCK DC....but.....allow signal to pass through" so that we can pass signal from one circuit element to another. IN the RF world they are also used to "tune" circuits... that is...... to configure circuits so that they work in a way that is sensitive to the frequency range. In other words..... some value of coil....with some value of capacitor across it.......will be TUNED to...and RESPOND to.....27 MHz and filter out everything else. In our radios...these are more often....NOT electrolytic...but may be a small plastic looking cap (some kind of film) or little yellow disc looking (usually ceramic). This does NOT cover all of them...but just so you get a general idea.

I'm sorry for the late clarification as I'm sure you'd already typed up the explanation regarding capacitors. The component appears to be a circle connected at two points on the board with an adjustable or rotatable lever that can be positioned rotated slightly less than 180 degrees. I will try to get a better picture of it. There are 4 or 5 of them on the board.

I gave it 24 hours to see if anyone came back with a copy of cb-104 but since no one has I will order one today off of Ebay. On that note, do you happen to know what Photofact would contain the Pace 113 base? I would like to order that as well.

 

[Champo]

I'm sorry for the late clarification as I'm sure you'd already typed up the explanation regarding capacitors. The component appears to be a circle connected at two points on the board with an adjustable or rotatable lever that can be positioned rotated slightly less than 180 degrees. I will try to get a better picture of it. There are 4 or 5 of them on the board.

I gave it 24 hours to see if anyone came back with a copy of cb-104 but since no one has I will order one today off of Ebay. On that note, do you happen to know what Photofact would contain the Pace 113 base? I would like to order that as well.

This thing.

 

[guitar_199]

THAT is called a trimmer. It is just a miniature PC board version of a potentiometer... just like your volume control...or squelch control....only smaller...and made for circuit adjustments...that will NOT need to be frequently made. Often.... they are set as part of an alignment.

BY THE WAY.....

I sent you a PM. Do you know how to check for those on here?

This thing.

 

[Champo]

THAT is called a trimmer. It is just a miniature PC board version of a potentiometer... just like your volume control...or squelch control....only smaller...and made for circuit adjustments...that will NOT need to be frequently made. Often.... they are set as part of an alignment.

BY THE WAY.....

I sent you a PM. Do you know how to check for those on here?

I think I just figured it out and replied but I could be wrong. As for the trimmer, I did move them to see if they made any difference during my initial troubleshooting but I believe I got them back to where they were originally positioned. I'm not sure how finite/sensitive they are. I hope I didn't craft an issue with that.