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What does it mean to unlock the clarifier?

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What does it mean to unlock the clarifier?

Post by Turbo-T » Monday, 02 March 2009, 12:00 PM

I have a Cobra 148 GTL radio. I was told when I bought it, that the clarifier had been unlocked.

What does this mean?

And is it a good or bad thing?

Also i have found on sideband, trying to tune people in seems to be a bit tedious. Is there an easy way of getting on friequency w/o having to play with the dial so much?
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Re: What does it mean to unlock the clarifier?

Post by Night Crawler » Monday, 02 March 2009, 12:21 PM

Turbo-T wrote:I have a Cobra 148 GTL radio. I was told when I bought it, that the clarifier had been unlocked.

What does this mean?
Your transmit frequency is tracking along with your receive frequency. Which means whatever frequency your receiving on your transmitting on when you move the clarifier.
Is it a good thing or bad? I like it, and no there isn't any easier way to get on frequency.

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Re: What does it mean to unlock the clarifier?

Post by PONY EXPRESS » Monday, 02 March 2009, 13:53 PM

I like the clarifier unlocked myself even though it is illegal.....
The only issue is that you need to tune into the other station 1st when you encounter someone with a locked clarifier .
That way you tune in on their transmit 1st and then they can just move their receive to lock you in.
Its not a real radio unless it has tubes and USB/LSB on the front panel ....



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Re: What does it mean to unlock the clarifier?

Post by Foxhunter » Monday, 02 March 2009, 14:28 PM

Both good answers above there for you TurboT. Legally, radio's have a clarifier that can vary your incoming signals so that you can "fine tune" them. It "clarifies" the incoming signals a little, clears it up so that it's more intelligible. Cobra radio calls theirs the "Deltatune" knob.

A popular mod is "unlocking" the clarifier so that it works on BOTH transmit AND receive. It's usually helpful to have it unlocked for transmit to talk to people who have radios:

--locked clarifiers
--off-frequency
--Galaxy radios that are drifting lol
--misaligned radios
--or many other situations/conditions

I do find varying frequency a bit annoying myself, especially in a situation where there are 8 or 10 guys and every other one is off a little---so you're constantly re-adjusting if you want to bother talking with them with fidelity. But, it's the "nature of the beast" with SSB and the myriad of types & quality of radios out there.

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Re: What does it mean to unlock the clarifier?

Post by Circuit Breaker » Monday, 02 March 2009, 15:22 PM

Foxhunter wrote:Both good answers above there for you TurboT. Legally, radio's have a clarifier that can vary your incoming signals so that you can "fine tune" them. It "clarifies" the incoming signals a little, clears it up so that it's more intelligible. Cobra radio calls theirs the "Deltatune" knob.
Actually, Delta Tune is used on AM. On SSB, Cobra calls their clarifiers Voicelock.
Foxhunter wrote: A popular mod is "unlocking" the clarifier so that it works on BOTH transmit AND receive. It's usually helpful to have it unlocked for transmit to talk to people who have radios:

--locked clarifiers
--off-frequency
--Galaxy radios that are drifting lol
--misaligned radios
--or many other situations/conditions
I have to disagree with you a little here. 1) if someone has a locked clarifier and yours is locked, it will make little difference. Since both transmitters are locked on frequency, you could both tune each other in without affecting your transmit frequency. 2) If you're talking to a station using a Galaxy radio that is drifting, if you both have unlocked clarifiers you'll be chasing each other across the band as you tune them in...then they tune you in and then you have to tune them in again and the cycle just keeps repeating itself. 3) Misaligned radios causes the same problem as I just mentioned.
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Re: What does it mean to unlock the clarifier?

Post by Foxhunter » Monday, 02 March 2009, 17:52 PM

Circuit Breaker wrote: Actually, Delta Tune is used on AM. On SSB, Cobra calls their clarifiers Voicelock.
Yes true that is the AM version of the clarifier, the deltatune. Same function, the Voicelock and Deltatune, but only different modes----"my bad".

Circuit Breaker wrote: 1) if someone has a locked clarifier and yours is locked, it will make little difference. Since both transmitters are locked on frequency, you could both tune each other in without affecting your transmit frequency.3) Misaligned radios causes the same problem as I just mentioned
I find that there are a high number of radios on-air that are not dead-on frequency, including TX. Having the room to shift up or down is handy, rather than being "fixed". Misaligned radios aka truckstop tune-jobs, do-it-yourselfer "golden screwdrivers", hacks etc have many radios off-target either TX, RX or both.

Circuit Breaker wrote: 2) If you're talking to a station using a Galaxy radio that is drifting, if you both have unlocked clarifiers you'll be chasing each other across the band as you tune them in...then they tune you in and then you have to tune them in again and the cycle just keeps repeating itself.
Yes I know that hehe, I was kind of being facetious there Circuit Breaker. Many guys hate Galaxy radios because of so many that purportedly drift so much. So yeah I thought that was funny and was waiting for someone to say something----no I wouldn't want to be following someone all-over just to talk with them lol. That's what I was hinting at.

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Re: What does it mean to unlock the clarifier?

Post by Circuit Breaker » Monday, 02 March 2009, 19:32 PM

The other night my wife and I were on our way home from dinner and I heard what sounded like SSB on channel 19. I flipped over to LSB and sure enough, two locals were having a QSO on 19...kind of stupid to do it on such a busy channel...but I digress. Anyway, I listened to them for a while. One station was using an RCI radio...I forget which one...I think it was a 2950. He sounded like crap. His SSB signal had a...well, the only way I can describe it is a flutter. It was rapidly fluctuating frequency back and forth. I had to jump in and mention it. The other station told me it was because the guy put his radio on the dash and the sun melted all the wax out of the pots. Yeah, umm, I don't really think so and even if it did...that shouldn't change the value of the component. He kept telling the guy that the flutter was going away as the radio warmed up but I didn't notice any difference.
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Re: What does it mean to unlock the clarifier?

Post by Turbo-T » Monday, 02 March 2009, 20:59 PM

Hhhmm....well thanks for the responses. I'm still a little confused, not as much as I was before.

So on a radio on let's say 27.165 on side band, with the clarifier locked you may not be actually transmitting on 27.165?

I've never been a fan of freq counters, but now I'm wondering if I should invest in one?

Also of interest.....I met someone on 40 today when skip was rolling, but he was local. Said he had a 148 GTL, but his had the front mount mic, and not the side mount mic like mine. We tried 40 lsb but couldn't get each other dialed in. I don't know if his clarifier was unlocked or not.

I have noticed my clarifier works in the 10-2 o clock position.
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Re: What does it mean to unlock the clarifier?

Post by Texas Mobil 219 » Tuesday, 03 March 2009, 4:30 AM

Turbo-T wrote:Hhhmm....well thanks for the responses. I'm still a little confused, not as much as I was before.

So on a radio on let's say 27.165 on side band, with the clarifier locked you may not be actually transmitting on 27.165?

I've never been a fan of freq counters, but now I'm wondering if I should invest in one?

Also of interest.....I met someone on 40 today when skip was rolling, but he was local. Said he had a 148 GTL, but his had the front mount mic, and not the side mount mic like mine. We tried 40 lsb but couldn't get each other dialed in. I don't know if his clarifier was unlocked or not.

I have noticed my clarifier works in the 10-2 o clock position.
Buying a Freq meter is a plus with a 148. I have one too. The freq meter is to let you know were you are at in the band. You can tune by ear. Myself i like all the lights and numbers. Look pretty cool at night.
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Re: What does it mean to unlock the clarifier?

Post by Turbo-T » Tuesday, 03 March 2009, 5:46 AM

Seeing as how my 148 isn't set up for one, that means I'd have to hire someone to set it up for a freq. counter?
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Re: What does it mean to unlock the clarifier?

Post by Circuit Breaker » Tuesday, 03 March 2009, 8:44 AM

Turbo-T wrote:Hhhmm....well thanks for the responses. I'm still a little confused, not as much as I was before.

So on a radio on let's say 27.165 on side band, with the clarifier locked you may not be actually transmitting on 27.165?
In theory, you should be. The manufacturer aligns the radios so that they transmit on frequency or as close to it as possible. For instance, they may only set it out to 5 digits so that their counter displays 27.165 MHz. But the actual frequency could be 27.16532 MHz. That won't make any difference on AM, but on SSB it can. Also, temperature will affect what frequency your radio is on...only a few Hertz. Enough to make a difference on SSB. With a locked clarifier, when you turn the knob, your transmit frequency will not change. It will stay the same...only your receive frequency will change. When you unlock a clarifier, both the transmit and receive frequency are supposed to be exactly the same and they should both change as you turn the knob. This can be good and bad. With an unlocked clarifier, you can "slide" between channels...for instance, 27.160 instead of 27.165. Is there any real advantage to this? Probably not because if the band was busy, you're still going to have interference from other stations. You'd be better off going above or below regular CB. The disadvantage to having an unlocked clarifier is that all radios are tuned differently using different equipment. Temperature will also affect them differently...usually cold. Some are more stable, others will drift more. This means that your radio will be transmitting on one frequency and the other station might be a few Hertz higher or lower. If you both have unlocked clarifiers, when you tune him in your transmit frequency follows. Now you sound off to the other station so they tune you in...and like you, their transmit follows their receive so now when he talks, he sounds off again. You can end up chasing each other back and forth. That's why it would be nice if these radios had the option to turn the unlocked clarifier on and off. It can probably be done quite easily.

I hope this clears it up a little more for you.
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Re: What does it mean to unlock the clarifier?

Post by Turbo-T » Tuesday, 03 March 2009, 12:57 PM

Thanks CB, that does clear it up better. Maybe that explains why I had trouble talking to a guy the other day who had the same radio I had, when we tried side band.

Can a side band radio have a switch installed to allow the locking and unlocking of the clarifier? I have considered maybe buying a brand new SSB radio with the freq. counter built in.

I have also heard about drifiting. I hear Galaxy radios are notorous for this. Are there any SSB radios that don't do this?
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Re: What does it mean to unlock the clarifier?

Post by Circuit Breaker » Tuesday, 03 March 2009, 18:50 PM

Probably the best SSB radio out there is an RCI 2950. Very stable and they have very good audio. But they're only okay on AM. It's difficult to make a radio that's awesome on both modes.
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Re: What does it mean to unlock the clarifier?

Post by Turbo-T » Wednesday, 05 August 2009, 12:28 PM

Circuit breaker, I think you hit dead on, I have someone else who says unlocking them is a bad idea because of what you pointed out...how it throws off your transmitting frequency and he says some people will not talk to you if you sound like you're off/can't get tuned into them.
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Re: What does it mean to unlock the clarifier?

Post by TheCBDoctor » Wednesday, 05 August 2009, 13:45 PM

Hi Turbo-T,

If a proper alignment is done after the clarifier is opened, then there is no problem with the Tx and Rx tracking. If you have a locked clarifier, and you are dead to nuts on frequency on Tx, then you will have no problem talking to another station. If you have an unlocked clarifier and the alignment was done correctly you can talk to any station no matter how many there are.

A locked clarifier that is off frequency on Tx will work because the other station can compensate for your radio Tx being off frequency. The problem is when you have a number of stations talking to each other, the radio you are using better be right on frequency on Tx or many of the stations will not be able to clarify you in, and still talk to the other stations.

If done properly having an open clarifier is an advantage. Some radios, like the new discontinued Cobra 148 GTL will not track on Tx and Rx no matter how hard you try. This is due to the unwanted high resistance in the cheaper tuning cans. I like the idea that is on the Galaxy 99v. There are two controls one adjusts both the TX and Rx and the other only adjusts the Rx. That is the best of both worlds because there will not be a station out there that you will not sound good to, and will not sound good coming back to you. I believe it is the 99V, I see less and less of them as the years go by.

By the way this only applies to Sideband since one can be off by 2,500 Hertz on AM and nobody would know the difference using a standard CB on AM. On SSB the tolerance is often plus or minus 20 Hertz.

Respectfully,
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Re: What does it mean to unlock the clarifier?

Post by 'Doc » Wednesday, 05 August 2009, 15:07 PM

So far, this is what's been said.
With a locked clarifier, typical and unmodified, the only thing you can change is the receiver's frequency. The transmitter's frequency stays as it's originally set. The benefit to that is that -if- the transmitter's frequency is set correctly, only a slight change in receiver frequency can make up for any differences from whatever cause. The biggest draw back to that is that the transmitter's frequency is seldom set to any particular exact standard. Close, but not always exact. Which one is the one not tuned correctly? Take your pick, you have a 50% chance of being right no matter which one you select.

With an unlocked clarifier you will have two variables, not just one. That means that -if- things aren't set correctly, that receiver frequency and transmitter frequency may not be close to tracking each other. Oh boy, that means that two people get to chase each other up/down the band! (Reminds me a lot of two 'Swan' owners waltzing.) If only one claifier is unlocked, it means you double your chances of being off frequency. Not a 50% chance of being 'on' anymore, but a 25% chance. If both clarifiers are unlocked and not tracking correctly, that means half of that, or 12.5% chance of being on the same frequency at least part of the time. It's really fun now!

So what's the solution to all that 'waltzing' around? Closer tolerances for what's 'right', a standard. That typiclly means that if the radio is normally capable of two decimal places accuracy, it needs to be set correctly to at least three decimal places, and the device used to set that has to be accurate to four decimal places. Just how many places who do that can claim that amount of accuracy? I've got a feeling the answer is not many. How about the number of places that are going to be willing to go to that much trouble? Same guess, not many. If those places are convinced that they should do things that way, what happens? Wanna gue$$?
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Re: What does it mean to unlock the clarifier?

Post by TheCBDoctor » Wednesday, 05 August 2009, 16:29 PM

Hi Doc,

Any radio that leaves my bench is dead to nuts on frequency. I always double check and calibrate my equipment on a regular basis. Any of ten radios I fix can talk to each other without touching the clarifier going from AM to any sideband. The clarifier is always at 12 o'clock top dead center.

In the real world it doesn't matter because as long as I say something, and it is understood, then I have made a positive contact. On the bench that is a different world, the radio is not just a radio, it is a finely tuned Instrument. If one could hear the frequencies coming from a CB it would be like music. The question is it in tune and would it be pleasant to the ear. When it leaves my bench it is.

On some of the new retro- radios, like the failed Cobra 148 GTL, the clarifier can not be opened successfully. I think giving out useful and insightful information can not be bad in a forum where we may all learn from each other.

Respectfully,
Best Regards,

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Re: What does it mean to unlock the clarifier?

Post by De_Wildfire » Friday, 14 August 2009, 18:39 PM

Circuit Breaker wrote:
Foxhunter wrote:Both good answers above there for you TurboT. Legally, radio's have a clarifier that can vary your incoming signals so that you can "fine tune" them. It "clarifies" the incoming signals a little, clears it up so that it's more intelligible. Cobra radio calls theirs the "Deltatune" knob.
Actually, Delta Tune is used on AM. On SSB, Cobra calls their clarifiers Voicelock.
Foxhunter wrote: A popular mod is "unlocking" the clarifier so that it works on BOTH transmit AND receive. It's usually helpful to have it unlocked for transmit to talk to people who have radios:

--locked clarifiers
--off-frequency
--Galaxy radios that are drifting lol
--misaligned radios
--or many other situations/conditions
I have to disagree with you a little here. 1) if someone has a locked clarifier and yours is locked, it will make little difference. Since both transmitters are locked on frequency, you could both tune each other in without affecting your transmit frequency. 2) If you're talking to a station using a Galaxy radio that is drifting, if you both have unlocked clarifiers you'll be chasing each other across the band as you tune them in...then they tune you in and then you have to tune them in again and the cycle just keeps repeating itself. 3) Misaligned radios causes the same problem as I just mentioned.
This is so TRUE!!!!!!! I have a TRAM D201 and when I use the VFO side of it, we keep chasing each other. It got to the point where I only use my TRAM D201 only on AM now and I use a TRAM D64 with a locked clarifier. If the other person is drifting, I remain on the same TX frequency and move my clarifier to tune the other station in. I think an unlocked clarifier is a pain in the @@@.

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Re: What does it mean to unlock the clarifier?

Post by TheCBDoctor » Saturday, 15 August 2009, 10:35 AM

Hi De_Wildfire

The Tram D201 and the 201A uses crystals for transmit and a tank circuit for receive. After a clarifier mod is done on the Tram, the crystal side is disconnected, and the receiver tank circuit is used for transmit. This produces a very dirty signal. If you saw what the signal looks like on a spectrum analyzer you would see why it bleeds over so badly. The pattern looks just like a Christmas tree. The spurious emissions are terrible.

Tank circuits are not allowed for transmitting per FCC regulation because the "Q" of the circuit is not as sharp as a crystal and tank circuits create harmonics. Add heat and the frequency will be all over the place. It is not so critical on AM but it is on Sideband.

Modern solid state radios do not have the same issues because they are still crystal control on Tx and Rx. That is why the Tram is so unstable when modified for an unlocked clarifier. It is technically not a clarifier on the Tram, it is a VFO (Variable Frequency Oscillator)

Just my 2 cents
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Re: What does it mean to unlock the clarifier?

Post by TheTeZ » Saturday, 15 August 2009, 10:39 AM

.



To Unlock The Clarifier clari·fier n. - To Make A Side Band Radio Truly Useful, To Separate The Best From The Rest.













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Re: What does it mean to unlock the clarifier?

Post by De_Wildfire » Saturday, 15 August 2009, 15:38 PM

TheCBDoctor wrote:Hi De_Wildfire

The Tram D201 and the 201A uses crystals for transmit and a tank circuit for receive. After a clarifier mod is done on the Tram, the crystal side is disconnected, and the receiver tank circuit is used for transmit. This produces a very dirty signal. If you saw what the signal looks like on a spectrum analyzer you would see why it bleeds over so badly. The pattern looks just like a Christmas tree. The spurious emissions are terrible.

Tank circuits are not allowed for transmitting per FCC regulation because the "Q" of the circuit is not as sharp as a crystal and tank circuits create harmonics. Add heat and the frequency will be all over the place. It is not so critical on AM but it is on Sideband.

Modern solid state radios do not have the same issues because they are still crystal control on Tx and Rx. That is why the Tram is so unstable when modified for an unlocked clarifier. It is technically not a clarifier on the Tram, it is a VFO (Variable Frequency Oscillator)

Just my 2 cents
Thanks for the information. That would explain when I was a kid why I got a lot of complaints on bleed and also maybe why I was tearing up the neighbors equipment on my PDL11. I remember one time I was on channel 28 and people also heard me on channel 32 at the same time but with a weaker signal. I think something in there was detuned. Right now, on 11 meters, I use the TRAM D64 and it is very clean. Once a month I'll fire up the Tram D201 but only for a brief TX contact just to keep things from "rotting" inside.


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