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Uniden 980 Cracked?: Clarifier + Channel Mod


Glad to see someone cracked the code....doesn't quite look like a totally workable solution yet though as he had to re-adjust the clarifier everytime he changed the channel.

Very cool that he took the time to figure it out.
 
Saw the video. Didn't look like he cracked it, unless I saw the wrong video. He did get the clarifier unlocked by using the standard method, which is to feed the clarifier circuit 8v in TX and RX.

He went as far as to replace the varactor diode with a SVC251 super-diode for added slide. But this made the clarifier a bit touchy too.

He put a switch on the side for channel change. So that could mean that he just put a switch board with different xtals on it to give it different freq ranges. ExitThirteen had done the same thing months ago before this video was made, so he did it first.
 
We're still waiting on ExitThirteen's findings.
Les found out that the radio's circuitry switched off the clarifier slide adjustment on tx. By pulling that wire from that plug and applying 8 volts it slides on tx as well as receive. I think he did something else in combination with that to get the clarifier to open up. I might buy one now or a Midland PC 787(like the 687's color).
 
We're still waiting on ExitThirteen's findings.
Les found out that the radio's circuitry switched off the clarifier slide adjustment on tx. By pulling that wire from that plug and applying 8 volts it slides on tx as well as receive. I think he did something else in combination with that to get the clarifier to open up. I might buy one now or a Midland PC 787(like the 687's color).

ALL radios switch off the clarifier 8v in TX mode, he didn't do anything different. That is typically the way it is done. If/when you ever start working on radios, padawan, you will find that out for yourself.

Don't give this radio too much hope to be cracked, LesComm seems to think so too. That is what Uniden had in mind when they designed this thing. Sure, you can switch out the xtal, but cracking the CPU is wishful thinking - IMO.

Nothing to see here folks, just move along . . .
 
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ALL radios switch off the clarifier 8v in TX mode, he didn't do anything different. That is typically the way it is done. If/when you ever start working on radios, padawan, you will find that out for yourself.

Don't give this radio too much hope to be cracked, LesComm seems to think so too. That is what Uniden had in mind when they designed this thing. Sure, you can switch out the xtal, but cracking the CPU is wishful thinking - IMO.

Nothing to see here folks, just move along . . .

Yep yep yep yep yep.
Martiens Yep Yep Yep - YouTube
"Weird Al" Yankovic - The Saga Begins - YouTube
 
One other thing, the TX will still need the broadband mod done too. But without the schematic it will be hard to figure this radio out.

Rotsa ruck, LesComm.

image012.jpg
 
In order for the clarifier to slide properly, the RX voltages have to be disabled first. This usually requires a diode and/or resistor to be removed out of circuit before you apply +8V to the clarifier.

As far as channels go, the only way to get extras is to swap out the 10.2417 crystal. A 10.6917 crystal will get you 27.415 - 27.855.

Cracking the CPU does nothing to the radio other than making the display show frequencies outside of the normal 40 channel band. The CPU chip only controls the display, nothing else.

I haven't had the time to play radio in a few months now, as I've been extremely busy. :( But these have been my findings for some time now, I just haven't been able to follow up and do a write-up on it.

~Cheers~
 
As far as channels go, the only way to get extras is to swap out the 10.2417 crystal. A 10.6917 crystal will get you 27.415 - 27.855.

when you did this, did you notice the same skipped freqs as shown in the lescom video?
missing 43 46 48... I assume this correlates to the "A" channels, although it seems a bit off...
 
No, I didn't have those kind of skips. The only skips I had were for the alpha channels, which are 27.445, 27.495, 27.545, 27.595, and 27.645.

The crystal swap I did just gives it another band of 40 channels. You can go 40 channels below channel 1 by using a 9.7917 crystal.

I did note tho that the TX and RX bandwidth is a little on the narrow side, it starts to lose TX/RX integrity after about 27.655 or so. There might be a way to broadband it, but I haven't had the time to explore that area yet.


~Cheers~
 
No, I didn't have those kind of skips. The only skips I had were for the alpha channels, which are 27.445, 27.495, 27.545, 27.595, and 27.645.

The crystal swap I did just gives it another band of 40 channels. You can go 40 channels below channel 1 by using a 9.7917 crystal.

I did note tho that the TX and RX bandwidth is a little on the narrow side, it starts to lose TX/RX integrity after about 27.655 or so. There might be a way to broadband it, but I haven't had the time to explore that area yet.


~Cheers~

So you didn't cook two previous 980's like Les did?
 
Lol!!

No, I didn't cook any radios. I still have my 980, and it works fine. Currently, it is back to stock, as I was going to actually build all the items needed for the channel conversion and clarifier mods, and do them right. I had aspirations of actually marketing a channel kit for the 980, but that fell thru when my grandfather got ill late last year. I had also at one point planned on doing a full writeup on the mods that I had done on the 980 for everyone here on the forum.

Someday when I get time, I'll go back to it, but I'm sure someone will have all the mods for the radio done by that time. But hey... at least I was able to get channels and mod the clarifier. Only thing I haven't experimented with much is the power output... would like to get rid of that junk RD16HHF1 final they use. But it's not an easy swap 'n' go. Uniden redesigned the TX output and basically took out 1 whole stage in the process... the 980 is devoid of any real "driver" stage, it goes from the predriver directly to the final from what I can tell.


Ahh, so many things I'd like to accomplish, so little time. *sigh*


~Cheers~
 
Lol!!

No, I didn't cook any radios. I still have my 980, and it works fine. Currently, it is back to stock, as I was going to actually build all the items needed for the channel conversion and clarifier mods, and do them right. I had aspirations of actually marketing a channel kit for the 980, but that fell thru when my grandfather got ill late last year. I had also at one point planned on doing a full writeup on the mods that I had done on the 980 for everyone here on the forum.

Someday when I get time, I'll go back to it, but I'm sure someone will have all the mods for the radio done by that time. But hey... at least I was able to get channels and mod the clarifier. Only thing I haven't experimented with much is the power output... would like to get rid of that junk RD16HHF1 final they use. But it's not an easy swap 'n' go. Uniden redesigned the TX output and basically took out 1 whole stage in the process... the 980 is devoid of any real "driver" stage, it goes from the predriver directly to the final from what I can tell.


Ahh, so many things I'd like to accomplish, so little time. *sigh*


~Cheers~

Yep. Big Brother radios by Uniden.
I know they're AM radios but have you checked out the Uniden PC 687/787 radios? I like the orange in the 687 but like the more features on the 787.
 
Think that Uniden is under pressure to keep the schematic and the Service manual out of the hands of the user. Perhaps from those who run the parent company, or the FCC, or possibly both.

Bad policy; but their bad choice.

Once again, it just goes to increase the value of thru-hole part radios and a resurgence in rebuilding and repairing the older radios. Be it a SuperStar export or the earliest 40 channel radios.
 
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