Modifying a RS Pro96.

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Did you try to read the percent decode from the CCs on this system......a good rate is anything above 75 and 50 is marginal. If the radio wont pick up the CCs it wont pick up the TGs either. You have to manually go to the bank where the CCs are and step through them until you hear motorboating. If you dont hear this, then that could be your problem. If you are pretty close to the tower 5mi I would say and dont hear this, then its time for RS repair.
When I do the manual mode, I get lots of "motorboating" pretty much continueous, the reading says:

M36:F590 xx% - the percentage goes up and down from about 5 -15 or so, but then will sometimes jump to 99% for short bursts, maybe 5 or 10 secs..so what does that mean ?

Some times it also reads

M36: 6939 xx% also jumping up and down between 5% and 99%.

are the numbers/letters before the percentage the different towers? (F590, 6939)
 

jamesa53

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When I do the manual mode, I get lots of "motorboating" pretty much continueous, the reading says:

M36:F590 xx% - the percentage goes up and down from about 5 -15 or so, but then will sometimes jump to 99% for short bursts, maybe 5 or 10 secs..so what does that mean ?

Some times it also reads

M36: 6939 xx% also jumping up and down between 5% and 99%.

are the numbers/letters before the percentage the different towers? (F590, 6939)
Sorry to tell you this, but you are either too far from the site, or have some kind of interference, or you need to send your PRO96 back to RS for a receiving issue. The tower I am about a mile away from gets consistent 99 percent and the one 5 miles away I get from 75-99 percent. This with the standard issue antenna for the 96.
 
Joined
Apr 14, 2010
Messages
83
Location
Halifax, NS
Sorry to tell you this, but you are either too far from the site, or have some kind of interference, or you need to send your PRO96 back to RS for a receiving issue. The tower I am about a mile away from gets consistent 99 percent and the one 5 miles away I get from 75-99 percent. This with the standard issue antenna for the 96.
I dont know what to do, I'd really hate to have to send it away, but, I'm to the point now that I've just removed all digital channels, cause at least then its doing something other then just breaking up and drowning out the clear sound from the Uniden lol ..might be time to contact The Shack, and see what they can do..

Thanks for all the suggestions, and help everyone. :)
 

martidav

KI7VLV
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Data Decode Threshold Settings

To your point... might you have suggestions on station management?

For example, our Seattle/King County Pub Safety system is what seems a standard multi-tower Similcast system. Ideally, I'd like to have all CC available (i.e. not locked out) as I tend to roam the county (which has mountains). At the same time, I don't want weaker towers being picked when I'm in the metro area as of course they're fuzzy. I'm sure you know the Pro-107 doesn't support managing CC on the device itself, so that won't work in the field.

I suppose I'm looking for a balance. Pick up towers only when I'm near them, and keep tuned to the usual one's in the metro area at home/work.

For the main towers CC, I have set 65H - 20Low with the THOUGHT being the radio will stay tuned to this one longer.

Ideas?

Thanks,
D

Did you try to read the percent decode from the CCs on this system......a good rate is anything above 75 and 50 is marginal. If the radio wont pick up the CCs it wont pick up the TGs either. You have to manually go to the bank where the CCs are and step through them until you hear motorboating. If you dont hear this, then that could be your problem. If you are pretty close to the tower 5mi I would say and dont hear this, then its time for RS repair.
 
Joined
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Messages
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Halifax, NS
Hey everyone, so I wanted to follow up on this post, since everyone was so helpfull(thanks again), and it has lots of good information in it for others with a Pro-96's or similar scanners, but I've been busy with other things, and didn't get around to editing the picture I will add below...

After reading, changing configs, uploading, doing software updates, and everything mentioned/suggested in this post, short of sending it back to RS, I decided to try "tinkering" with some things inside, mainly the 3 small "dials" or whatever you wanna call them, as I have highlighted in Red in the picture..I read in a post somewhere for another RS scanner, that those would fine tune it somehow..at the time I didnt pay much attention to it, as it was for a different model, and I didnt have it open at the time to compare, so I don't have a link, which is bothering me now lol..

So, I opened it up, then plugged it back in, positioning it so I could see the screen as well as turn the small dials/screws easily, turned it on, and manually tuned it to the controi channel for the Halifax Tower(Geizers Hill) so it displayed the % for recieved signal(which hovered at the 12-20% range before this process), then took a small Phillips head screwdriver and put it on the bottom dial (VR4), and began to delicatly turn it a small amount counter clockwise, and sure enough, as I turned the dial/screw, my % started to climb, I turned it about 1/4 of a turn total, maybe a bit more, in the end, I was able to get it to read the control channel at 75-90% consistantly...

So, I decide to hit the scan button, and sure eneough, Clean, Clear, like the day I bought it in Texas listening to Houston PD, it works...no more garbling, or digital noise, or anything, just clear audio on all the channels I was trying to scan..I'm pretty sure my pants moved at that point :p Anyways, I dont know what exactly I did there, but it sure as hell made a big difference.

It would be cool if someone who know's more could explain how what I did works, it was a simple fix, that anyone could do who is comfortable with opening the case..and would be great to share.

Here's the link to the picture, its to large to upload, but I wanted to make it clear for others to see:

https://docs.google.com/leaf?id=0Bze_Yj7bbgaGNTBmZjA4NjItYjU1Ny00MTQ4LThkZDUtYmI2ZTgyZDJiMWI4&hl=en

If you click on the image again once it opens, you will get a full window pic, much easier to see :)
 

dsego

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Dec 24, 2009
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Indiana
I was having the same problem. When I tweaked the adjustment my signal went from 5% to 60% and I now can receive everything crystal clear. I was about ready to send it for repair.

Thanks for the info!
 

jamesa53

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Can one of the radio wizards step in here and say exactly what this adjustment is for (yes gmclam I mean you).
 

RickS31

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While I don't have a schematic of the 96, I can tell you from many years in the radio hobby including both building receivers as well as aligning them, that these are what are called trimmer variable capacitors. They are typically used in fine adjustments in both the RF front ends for both Local Oscillator tweaking as well as RF amplifier tuning. These radios use (as do most current receivers) Phase Locked Loop circuitry which does the lions share of all the various band tuning. A PLL is an intelligent circuit that takes the frequency request from the CPU/keyboard and tunes the VHF/UHF/etc. circuits for tha requested frequency. It utilizes heavy feedback from these RF circuits to tweak the circuits to center exactly on that frequency electronically.

These adjustments are usually provided to make up for differences in components (primarily in the RF circuits) and layout so that it does indeed go to the exact center of the requested frequency. It sounds like either some of these components aged or the radio took some heavy shocks such that the PLL could not adjust enough to make up for it. By adjusting those, you brought it back to spec'ed range. By the same token, with no proper test equipment, you can also adjust these totally improperly so that the radio won't work at all. Always adjust these, if you must for test, minimally and mark where you started so you can return them if no help is noticed on adjustment.
 

RickS31

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I'll fall on my sword here. These are variable resistors (pots). Just looked at the full sized picture. Since it looks like they're around the PLL, they also probably provide fine adjustment of the Loop and frequency. I'd also like to see a schematic of the unit. From that I could give a more definitive explanation of what exactly they're doing.

For any of you interested in a more in-depth explanation of the circuits I mentioned above, please feel free to peruse the following descriptions:

Superheterodyne receiver - Wikipedia, the free encyclopedia

Phase-locked loop - Wikipedia, the free encyclopedia
 
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martidav

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Good day,

Beside L/O the distant and therefore weak Simulcast towers, is adjusting the Decode Threshold the best way to snag and lock on the strongest tower?

I prefer not to L/O any tower as I roam the county.

Perhaps attenuate the preferred and usually strong tower? Or is it all the threshold settings?

What about NFM?

Sorry the question spam, I'm just at a loss.

Thanks,

Dave
 

derpotts

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Joined
Feb 25, 2004
Messages
23
Location
baltimore
pro 96

I had a problem where i could not hear any digital on my scanner. So i follow the instructions and my percentage on the one control channel was at 27%. I then seen where i had to adjusted the
VR4 and i did so now I'm at 96%. Now i can hear all the digital channel nice and clear. not the problem is i can not hear any conventional channels, what did i do wrong i only mess with the VR4 and nothing else.
 

scotty-o

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Just a heads up, If you want to try this on a 2096, the pot is labeled VR3 on that circuit board.....
 

kb3isq

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I adjusted VR4 and percentage went from 0 to 24, I can not get it any higher while another PRO96 which works fine shoes 92% ? This is working on a ufh 460.xxx control channel. What do the other two pots VR2 & 3 do are they for different frequencies?
 

bbernstein

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Austin, TX
Woo Hoo It Worked!

Woo Hoo, it worked for me! I turned the VR4 screw 1/4 turn counter clock wise, and it turned my expensive paper weight into a working radio again!!! Thank you!!!

Hey everyone, so I wanted to follow up on this post, since everyone was so helpfull(thanks again), and it has lots of good information in it for others with a Pro-96's or similar scanners, but I've been busy with other things, and didn't get around to editing the picture I will add below...

After reading, changing configs, uploading, doing software updates, and everything mentioned/suggested in this post, short of sending it back to RS, I decided to try "tinkering" with some things inside, mainly the 3 small "dials" or whatever you wanna call them, as I have highlighted in Red in the picture..I read in a post somewhere for another RS scanner, that those would fine tune it somehow..at the time I didnt pay much attention to it, as it was for a different model, and I didnt have it open at the time to compare, so I don't have a link, which is bothering me now lol..

So, I opened it up, then plugged it back in, positioning it so I could see the screen as well as turn the small dials/screws easily, turned it on, and manually tuned it to the controi channel for the Halifax Tower(Geizers Hill) so it displayed the % for recieved signal(which hovered at the 12-20% range before this process), then took a small Phillips head screwdriver and put it on the bottom dial (VR4), and began to delicatly turn it a small amount counter clockwise, and sure enough, as I turned the dial/screw, my % started to climb, I turned it about 1/4 of a turn total, maybe a bit more, in the end, I was able to get it to read the control channel at 75-90% consistantly...

So, I decide to hit the scan button, and sure eneough, Clean, Clear, like the day I bought it in Texas listening to Houston PD, it works...no more garbling, or digital noise, or anything, just clear audio on all the channels I was trying to scan..I'm pretty sure my pants moved at that point :p Anyways, I dont know what exactly I did there, but it sure as hell made a big difference.

It would be cool if someone who know's more could explain how what I did works, it was a simple fix, that anyone could do who is comfortable with opening the case..and would be great to share.

Here's the link to the picture, its to large to upload, but I wanted to make it clear for others to see:

https://docs.google.com/leaf?id=0Bze_Yj7bbgaGNTBmZjA4NjItYjU1Ny00MTQ4LThkZDUtYmI2ZTgyZDJiMWI4&hl=en

If you click on the image again once it opens, you will get a full window pic, much easier to see :)
 

milf

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Also worked for me, and has made listening to an P25 LSM system actually enjoyable again. I was getting very low decode rates, and now get minimum of 50% decode at all times, and very little multipath distortion, whereas I was getting drowned in it.
 
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